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Sample records for validation plan volume

  1. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

    Science.gov (United States)

    Magro, G.; Molinelli, S.; Mairani, A.; Mirandola, A.; Panizza, D.; Russo, S.; Ferrari, A.; Valvo, F.; Fossati, P.; Ciocca, M.

    2015-09-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5-30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus® chamber. An EBT3® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification.

  2. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

    International Nuclear Information System (INIS)

    Magro, G; Molinelli, S; Mairani, A; Mirandola, A; Panizza, D; Russo, S; Valvo, F; Fossati, P; Ciocca, M; Ferrari, A

    2015-01-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5–30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo ® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus ® chamber. An EBT3 ® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size ratio. The accuracy of the TPS was proved to be clinically acceptable in all cases but very small and shallow volumes. In this contest, the use of MC to validate TPS results proved to be a reliable procedure for pre-treatment plan verification. (paper)

  3. Automated planning volume definition in soft-tissue sarcoma adjuvant brachytherapy

    International Nuclear Information System (INIS)

    Lee, Eva K.; Fung, Albert Y.C.; Zaider, Marco; Brooks, J. Paul

    2002-01-01

    soft-tissue sarcoma tumour beds within various anatomical structures. For each of 15 patient cases considered, the algorithm takes approximately 2 min to generate the planning volume. Although the tumour shapes are rather different, the algorithm consistently generates planning volumes that visually demonstrate smooth curves compactly encapsulating the circles. This general-purpose contouring algorithm works well whether the catheters are all close together, spread far apart in the plane or arranged in a convoluted way. The automatic contouring algorithm significantly reduces labour time and provides a consistent and objective method for determining planning volumes for soft-tissue sarcoma. Further studies are needed to validate the significance of the resulting planning volumes in designing treatment plans and the role that sophisticated brachytherapy treatment planning optimization may have in producing good plans. (author)

  4. Automated planning volume definition in soft-tissue sarcoma adjuvant brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eva K. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); School of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, GA (United States); Fung, Albert Y.C.; Zaider, Marco [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY (United States); Brooks, J. Paul [School of Industrial and Systems Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

    2002-06-07

    soft-tissue sarcoma tumour beds within various anatomical structures. For each of 15 patient cases considered, the algorithm takes approximately 2 min to generate the planning volume. Although the tumour shapes are rather different, the algorithm consistently generates planning volumes that visually demonstrate smooth curves compactly encapsulating the circles. This general-purpose contouring algorithm works well whether the catheters are all close together, spread far apart in the plane or arranged in a convoluted way. The automatic contouring algorithm significantly reduces labour time and provides a consistent and objective method for determining planning volumes for soft-tissue sarcoma. Further studies are needed to validate the significance of the resulting planning volumes in designing treatment plans and the role that sophisticated brachytherapy treatment planning optimization may have in producing good plans. (author)

  5. Highly Efficient Training, Refinement, and Validation of a Knowledge-based Planning Quality-Control System for Radiation Therapy Clinical Trials

    Energy Technology Data Exchange (ETDEWEB)

    Li, Nan; Carmona, Ruben [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Sirak, Igor; Kasaova, Linda [Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove (Czech Republic); Followill, David [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Michalski, Jeff; Bosch, Walter; Straube, William [Department of Radiation Oncology, Washington University in St Louis, St Louis, Missouri (United States); Mell, Loren K. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Moore, Kevin L., E-mail: kevinmoore@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States)

    2017-01-01

    Purpose: To demonstrate an efficient method for training and validation of a knowledge-based planning (KBP) system as a radiation therapy clinical trial plan quality-control system. Methods and Materials: We analyzed 86 patients with stage IB through IVA cervical cancer treated with intensity modulated radiation therapy at 2 institutions according to the standards of the INTERTECC (International Evaluation of Radiotherapy Technology Effectiveness in Cervical Cancer, National Clinical Trials Network identifier: 01554397) protocol. The protocol used a planning target volume and 2 primary organs at risk: pelvic bone marrow (PBM) and bowel. Secondary organs at risk were rectum and bladder. Initial unfiltered dose-volume histogram (DVH) estimation models were trained using all 86 plans. Refined training sets were created by removing sub-optimal plans from the unfiltered sample, and DVH estimation models… and DVH estimation models were constructed by identifying 30 of 86 plans emphasizing PBM sparing (comparing protocol-specified dosimetric cutpoints V{sub 10} (percentage volume of PBM receiving at least 10 Gy dose) and V{sub 20} (percentage volume of PBM receiving at least 20 Gy dose) with unfiltered predictions) and another 30 of 86 plans emphasizing bowel sparing (comparing V{sub 40} (absolute volume of bowel receiving at least 40 Gy dose) and V{sub 45} (absolute volume of bowel receiving at least 45 Gy dose), 9 in common with the PBM set). To obtain deliverable KBP plans, refined models must inform patient-specific optimization objectives and/or priorities (an auto-planning “routine”). Four candidate routines emphasizing different tradeoffs were composed, and a script was developed to automatically re-plan multiple patients with each routine. After selection of the routine that best met protocol objectives in the 51-patient training sample (KBP{sub FINAL}), protocol-specific DVH metrics and normal tissue complication probability were compared for original

  6. An innovative method of planning and displaying flap volume in DIEP flap breast reconstructions.

    Science.gov (United States)

    Hummelink, S; Verhulst, Arico C; Maal, Thomas J J; Hoogeveen, Yvonne L; Schultze Kool, Leo J; Ulrich, Dietmar J O

    2017-07-01

    Determining the ideal volume of the harvested flap to achieve symmetry in deep inferior epigastric artery perforator (DIEP) flap breast reconstructions is complex. With preoperative imaging techniques such as 3D stereophotogrammetry and computed tomography angiography (CTA) available nowadays, we can combine information to preoperatively plan the optimal flap volume to be harvested. In this proof-of-concept, we investigated whether projection of a virtual flap planning onto the patient's abdomen using a projection method could result in harvesting the correct flap volume. In six patients (n = 9 breasts), 3D stereophotogrammetry and CTA data were combined from which a virtual flap planning was created comprising perforator locations, blood vessel trajectory and flap size. All projected perforators were verified with Doppler ultrasound. Intraoperative flap measurements were collected to validate the determined flap delineation volume. The measured breast volume using 3D stereophotogrammetry was 578 ± 127 cc; on CTA images, 527 ± 106 cc flap volumes were planned. The nine harvested flaps weighed 533 ± 109 g resulting in a planned versus harvested flap mean difference of 5 ± 27 g (flap density 1.0 g/ml). In 41 out of 42 projected perforator locations, a Doppler signal was audible. This proof-of-concept shows in small numbers that flap volumes can be included into a virtual DIEP flap planning, and transferring the virtual planning to the patient through a projection method results in harvesting approximately the same volume during surgery. In our opinion, this innovative approach is the first step in consequently achieving symmetric breast volumes in DIEP flap breast reconstructions. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. Improved robotic stereotactic body radiation therapy plan quality and planning efficacy for organ-confined prostate cancer utilizing overlap-volume histogram-driven planning methodology

    International Nuclear Information System (INIS)

    Wu, Binbin; Pang, Dalong; Lei, Siyuan; Gatti, John; Tong, Michael; McNutt, Todd; Kole, Thomas; Dritschilo, Anatoly; Collins, Sean

    2014-01-01

    Background and purpose: This study is to determine if the overlap-volume histogram (OVH)-driven planning methodology can be adapted to robotic SBRT (CyberKnife Robotic Radiosurgery System) to further minimize the bladder and rectal doses achieved in plans manually-created by clinical planners. Methods and materials: A database containing clinically-delivered, robotic SBRT plans (7.25 Gy/fraction in 36.25 Gy) of 425 patients with localized prostate cancer was used as a cohort to establish an organ’s distance-to-dose model. The OVH-driven planning methodology was refined by adding the PTV volume factor to counter the target’s dose fall-off effect and incorporated into Multiplan to automate SBRT planning. For validation, automated plans (APs) for 12 new patients were generated, and their achieved dose/volume values were compared to the corresponding manually-created, clinically-delivered plans (CPs). A two-sided, Wilcoxon rank-sum test was used for statistical comparison with a significance level of p < 0.05. Results: PTV’s V(36.25 Gy) was comparable: 95.6% in CPs comparing to 95.1% in APs (p = 0.2). On average, the refined approach lowered V(18.12 Gy) to the bladder and rectum by 8.2% (p < 0.05) and 6.4% (p = 0.14). A physician confirmed APs were clinically acceptable. Conclusions: The improvements in APs could further reduce toxicities observed in SBRT for organ-confined prostate cancer

  8. Dosimetric accuracy of a treatment planning system for actively scanned proton beams and small target volumes: Monte Carlo and experimental validation

    CERN Document Server

    Magro, G; Mairani, A; Mirandola, A; Panizza, D; Russo, S; Ferrari, A; Valvo, F; Fossati, P; Ciocca, M

    2015-01-01

    This study was performed to evaluate the accuracy of a commercial treatment planning system (TPS), in optimising proton pencil beam dose distributions for small targets of different sizes (5–30 mm side) located at increasing depths in water. The TPS analytical algorithm was benchmarked against experimental data and the FLUKA Monte Carlo (MC) code, previously validated for the selected beam-line. We tested the Siemens syngo® TPS plan optimisation module for water cubes fixing the configurable parameters at clinical standards, with homogeneous target coverage to a 2 Gy (RBE) dose prescription as unique goal. Plans were delivered and the dose at each volume centre was measured in water with a calibrated PTW Advanced Markus® chamber. An EBT3® film was also positioned at the phantom entrance window for the acquisition of 2D dose maps. Discrepancies between TPS calculated and MC simulated values were mainly due to the different lateral spread modeling and resulted in being related to the field-to-spot size r...

  9. SeaWiFS calibration and validation plan, volume 3

    International Nuclear Information System (INIS)

    Hooker, S.B.; Firestone, E.R.; Mcclain, C.R.; Esaias, W.E.; Barnes, W.; Guenther, B.; Endres, D.; Mitchell, B.G.; Barnes, R.

    1992-09-01

    The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) will be the first ocean-color satellite since the Nimbus-7 Coastal Zone Color Scanner (CZCS), which ceased operation in 1986. Unlike the CZCS, which was designed as a proof-of-concept experiment, SeaWiFS will provide routine global coverage every 2 days and is designed to provide estimates of photosynthetic concentrations of sufficient accuracy for use in quantitative studies of the ocean's primary productivity and biogeochemistry. A review of the CZCS mission is included that describes that data set's limitations and provides justification for a comprehensive SeaWiFS calibration and validation program. To accomplish the SeaWiFS scientific objectives, the sensor's calibration must be constantly monitored, and robust atmospheric corrections and bio-optical algorithms must be developed. The plan incorporates a multi-faceted approach to sensor calibration using a combination of vicarious (based on in situ observations) and onboard calibration techniques. Because of budget constraints and the limited availability of ship resources, the development of the operational algorithms (atmospheric and bio-optical) will rely heavily on collaborations with the Earth Observing System (EOS), the Moderate Resolution Imaging Spectrometer (MODIS) oceans team, and projects sponsored by other agencies, e.g., the U.S. Navy and the National Science Foundation (NSF). Other elements of the plan include the routine quality control of input ancillary data (e.g., surface wind, surface pressure, ozone concentration, etc.) used in the processing and verification of the level-0 (raw) data to level-1 (calibrated radiances), level-2 (derived products), and level-3 (gridded and averaged derived data) products

  10. Research program plan: piping. Volume 3

    International Nuclear Information System (INIS)

    Vagins, M.; Strosnider, J.

    1985-07-01

    Regulatory issues related to piping can be divided into the three areas of pipe cracking, postulated design basis pipe breaks, and design of piping for seismic and other dynamic loads. The first two of these issues are in the domain of the Materials Engineering Branch (MEBR), while the last of the three issues is the responsibility of the Mechanical/Structural Engineering Branch. This volume of the MEBR Research Plan defines the critical aspects of the pipe cracking and postulated design basis pipe break issues and identifies those research efforts and results necessary for their resolution. In general, the objectives of the MERB Piping Research Program are to provide experimentally validated analytic techniques and appropriate material properties characterization methods and data to support regulatory activities related to evaluating and ensuring piping integrity

  11. STAR-CCM+ Verification and Validation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Pointer, William David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-30

    The commercial Computational Fluid Dynamics (CFD) code STAR-CCM+ provides general purpose finite volume method solutions for fluid dynamics and energy transport. This document defines plans for verification and validation (V&V) of the base code and models implemented within the code by the Consortium for Advanced Simulation of Light water reactors (CASL). The software quality assurance activities described herein are port of the overall software life cycle defined in the CASL Software Quality Assurance (SQA) Plan [Sieger, 2015]. STAR-CCM+ serves as the principal foundation for development of an advanced predictive multi-phase boiling simulation capability within CASL. The CASL Thermal Hydraulics Methods (THM) team develops advanced closure models required to describe the subgrid-resolution behavior of secondary fluids or fluid phases in multiphase boiling flows within the Eulerian-Eulerian framework of the code. These include wall heat partitioning models that describe the formation of vapor on the surface and the forces the define bubble/droplet dynamic motion. The CASL models are implemented as user coding or field functions within the general framework of the code. This report defines procedures and requirements for V&V of the multi-phase CFD capability developed by CASL THM. Results of V&V evaluations will be documented in a separate STAR-CCM+ V&V assessment report. This report is expected to be a living document and will be updated as additional validation cases are identified and adopted as part of the CASL THM V&V suite.

  12. CT-guided intracavitary radiotherapy for cervical cancer: Comparison of conventional point A plan with clinical target volume-based three-dimensional plan using dose-volume parameters

    International Nuclear Information System (INIS)

    Shin, Kyung Hwan; Kim, Tae Hyun; Cho, Jung Keun; Kim, Joo-Young; Park, Sung Yong; Park, Sang-Yoon; Kim, Dae Yong; Chie, Eui Kyu; Pyo, Hong Ryull; Cho, Kwan Ho

    2006-01-01

    Purpose: To perform an intracavitary radiotherapy (ICR) plan comparison between the conventional point A plan (conventional plan) and computed tomography (CT)-guided clinical target volume-based plan (CTV plan) by analysis of the quantitative dose-volume parameters and irradiated volumes of organs at risk in patients with cervical cancer. Methods and Materials: Thirty plans for 192 Ir high-dose-rate ICR after 30-40-Gy external beam radiotherapy were investigated. CT images were acquired at the first ICR session with artifact-free applicators in place. The gross tumor volume, clinical target volume (CTV), point A, and International Commission on Radiation Units and Measurements Report 38 rectal and bladder points were defined on reconstructed CT images. A fractional 100% dose was prescribed to point A in the conventional plan and to the outermost point to cover all CTVs in the CTV plan. The reference volume receiving 100% of the prescribed dose (V ref ), and the dose-volume parameters of the coverage index, conformal index, and external volume index were calculated from the dose-volume histogram. The bladder, rectal point doses, and percentage of volumes receiving 50%, 80%, and 100% of the prescribed dose were also analyzed. Results: Conventional plans were performed, and patients were categorized on the basis of whether the 100% isodose line of point A prescription dose fully encompassed the CTV (Group 1, n = 20) or not (Group 2, n = 10). The mean gross tumor volume (11.6 cm 3 ) and CTV (24.9 cm 3 ) of Group 1 were smaller than the corresponding values (23.7 and 44.7 cm 3 , respectively) for Group 2 (p = 0.003). The mean V ref for all patients was 129.6 cm 3 for the conventional plan and 97.0 cm 3 for the CTV plan (p = 0.003). The mean V ref in Group 1 decreased markedly with the CTV plan (p < 0.001). For the conventional and CTV plans in all patients, the mean coverage index, conformal index, and external volume index were 0.98 and 1.0, 0.23 and 0.34, and 3.86 and

  13. CIPS Validation Data Plan

    International Nuclear Information System (INIS)

    Dinh, Nam

    2012-01-01

    This report documents analysis, findings and recommendations resulted from a task 'CIPS Validation Data Plan (VDP)' formulated as an POR4 activity in the CASL VUQ Focus Area (FA), to develop a Validation Data Plan (VDP) for Crud-Induced Power Shift (CIPS) challenge problem, and provide guidance for the CIPS VDP implementation. The main reason and motivation for this task to be carried at this time in the VUQ FA is to bring together (i) knowledge of modern view and capability in VUQ, (ii) knowledge of physical processes that govern the CIPS, and (iii) knowledge of codes, models, and data available, used, potentially accessible, and/or being developed in CASL for CIPS prediction, to devise a practical VDP that effectively supports the CASL's mission in CIPS applications.

  14. CIPS Validation Data Plan

    Energy Technology Data Exchange (ETDEWEB)

    Nam Dinh

    2012-03-01

    This report documents analysis, findings and recommendations resulted from a task 'CIPS Validation Data Plan (VDP)' formulated as an POR4 activity in the CASL VUQ Focus Area (FA), to develop a Validation Data Plan (VDP) for Crud-Induced Power Shift (CIPS) challenge problem, and provide guidance for the CIPS VDP implementation. The main reason and motivation for this task to be carried at this time in the VUQ FA is to bring together (i) knowledge of modern view and capability in VUQ, (ii) knowledge of physical processes that govern the CIPS, and (iii) knowledge of codes, models, and data available, used, potentially accessible, and/or being developed in CASL for CIPS prediction, to devise a practical VDP that effectively supports the CASL's mission in CIPS applications.

  15. HEDR model validation plan

    International Nuclear Information System (INIS)

    Napier, B.A.; Gilbert, R.O.; Simpson, J.C.; Ramsdell, J.V. Jr.; Thiede, M.E.; Walters, W.H.

    1993-06-01

    The Hanford Environmental Dose Reconstruction (HEDR) Project has developed a set of computational ''tools'' for estimating the possible radiation dose that individuals may have received from past Hanford Site operations. This document describes the planned activities to ''validate'' these tools. In the sense of the HEDR Project, ''validation'' is a process carried out by comparing computational model predictions with field observations and experimental measurements that are independent of those used to develop the model

  16. A method to combine target volume data from 3D and 4D planned thoracic radiotherapy patient cohorts for machine learning applications

    NARCIS (Netherlands)

    Johnson, Corinne; Price, Gareth; Khalifa, Jonathan; Faivre-Finn, Corinne; Dekker, Andre; Moore, Christopher; van Herk, Marcel

    2017-01-01

    The gross tumour volume (GTV) is predictive of clinical outcome and consequently features in many machine-learned models. 4D-planning, however, has prompted substitution of the GTV with the internal gross target volume (iGTV). We present and validate a method to synthesise GTV data from the iGTV,

  17. Dosimetric validation for an automatic brain metastases planning software using single-isocenter dynamic conformal arcsDosimetric validation for an automatic brain metastases planning software using single-isocenter dynamic conformal arcs.

    Science.gov (United States)

    Liu, Haisong; Li, Jun; Pappas, Evangelos; Andrews, David; Evans, James; Werner-Wasik, Maria; Yu, Yan; Dicker, Adam; Shi, Wenyin

    2016-09-08

    An automatic brain-metastases planning (ABMP) software has been installed in our institution. It is dedicated for treating multiple brain metastases with radiosurgery on linear accelerators (linacs) using a single-setup isocenter with noncoplanar dynamic conformal arcs. This study is to validate the calculated absolute dose and dose distribution of ABMP. Three types of measurements were performed to validate the planning software: 1, dual micro ion chambers were used with an acrylic phantom to measure the absolute dose; 2, a 3D cylindrical phantom with dual diode array was used to evaluate 2D dose distribution and point dose for smaller targets; and 3, a 3D pseudo-in vivo patient-specific phantom filled with polymer gels was used to evaluate the accuracy of 3D dose distribution and radia-tion delivery. Micro chamber measurement of two targets (volumes of 1.2 cc and 0.9 cc, respectively) showed that the percentage differences of the absolute dose at both targets were less than 1%. Averaged GI passing rate of five different plans measured with the diode array phantom was above 98%, using criteria of 3% dose difference, 1 mm distance to agreement (DTA), and 10% low-dose threshold. 3D gel phantom measurement results demonstrated a 3D displacement of nine targets of 0.7 ± 0.4 mm (range 0.2 ~ 1.1 mm). The averaged two-dimensional (2D) GI passing rate for several region of interests (ROI) on axial slices that encompass each one of the nine targets was above 98% (5% dose difference, 2 mm DTA, and 10% low-dose threshold). Measured D95, the minimum dose that covers 95% of the target volume, of the nine targets was 0.7% less than the calculated D95. Three different types of dosimetric verification methods were used and proved the dose calculation of the new automatic brain metastases planning (ABMP) software was clinical acceptable. The 3D pseudo-in vivo patient-specific gel phantom test also served as an end-to-end test for validating not only the dose calculation, but the

  18. Treatment plan evaluation using dose-volume histogram (DVH) and spatial dose-volume histogram (zDVH)

    International Nuclear Information System (INIS)

    Cheng, C.-W.; Das, Indra J.

    1999-01-01

    Objective: The dose-volume histogram (DVH) has been accepted as a tool for treatment-plan evaluation. However, DVH lacks spatial information. A new concept, the z-dependent dose-volume histogram (zDVH), is presented as a supplement to the DVH in three-dimensional (3D) treatment planning to provide the spatial variation, as well as the size and magnitude of the different dose regions within a region of interest. Materials and Methods: Three-dimensional dose calculations were carried out with various plans for three disease sites: lung, breast, and prostate. DVHs were calculated for the entire volume. A zDVH is defined as a differential dose-volume histogram with respect to a computed tomographic (CT) slice position. In this study, zDVHs were calculated for each CT slice in the treatment field. DVHs and zDVHs were compared. Results: In the irradiation of lung, DVH calculation indicated that the treatment plan satisfied the dose-volume constraint placed on the lung and zDVH of the lung revealed that a sizable fraction of the lung centered about the central axis (CAX) received a significant dose, a situation that warranted a modification of the treatment plan due to the removal of one lung. In the irradiation of breast with tangential fields, the DVH showed that about 7% of the breast volume received at least 110% of the prescribed dose (PD) and about 11% of the breast received less than 98% PD. However, the zDVHs of the breast volume in each of seven planes showed the existence of high-dose regions of 34% and 15%, respectively, of the volume in the two caudal-most planes and cold spots of about 40% in the two cephalic planes. In the treatment planning of prostate, DVHs showed that about 15% of the bladder and 40% of the rectum received 102% PD, whereas about 30% of the bladder and 50% of the rectum received the full dose. Taking into account the hollow structure of both the bladder and the rectum, the dose-surface histograms (DSH) showed larger hot-spot volume, about

  19. SU-E-J-244: Development and Validation of a Knowledge Based Planning Model for External Beam Radiation Therapy of Locally Advanced Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z; Kennedy, A [Sarah Cannon, Nashville, TN (United States); Larsen, E; Hayes, C; Grow, A [North Florida Cancer Center, Gainesville, FL (United States); Bahamondes, S.; Zheng, Y; Wu, X [JFK Comprehensive Cancer Institute, Lake Worth, FL (United States); Choi, M; Pai, S [Good Samaritan Hospital, Los Gatos, CA (United States); Li, J [Doctors Hospital of Augusta, Augusta, GA (United States); Cranford, K [Trident Medical Center, Charleston, SC (United States)

    2015-06-15

    Purpose: The study aims to develop and validate a knowledge based planning (KBP) model for external beam radiation therapy of locally advanced non-small cell lung cancer (LA-NSCLC). Methods: RapidPlan™ technology was used to develop a lung KBP model. Plans from 65 patients with LA-NSCLC were used to train the model. 25 patients were treated with VMAT, and the other patients were treated with IMRT. Organs-at-risk (OARs) included right lung, left lung, heart, esophagus, and spinal cord. DVH and geometric distribution DVH were extracted from the treated plans. The model was trained using principal component analysis and step-wise multiple regression. Box plot and regression plot tools were used to identify geometric outliers and dosimetry outliers and help fine-tune the model. The validation was performed by (a) comparing predicted DVH boundaries to actual DVHs of 63 patients and (b) using an independent set of treatment planning data. Results: 63 out of 65 plans were included in the final KBP model with PTV volume ranging from 102.5cc to 1450.2cc. Total treatment dose prescription varied from 50Gy to 70Gy based on institutional guidelines. One patient was excluded due to geometric outlier where 2.18cc of spinal cord was included in PTV. The other patient was excluded due to dosimetric outlier where the dose sparing to spinal cord was heavily enforced in the clinical plan. Target volume, OAR volume, OAR overlap volume percentage to target, and OAR out-of-field volume were included in the trained model. Lungs and heart had two principal component scores of GEDVH, whereas spinal cord and esophagus had three in the final model. Predicted DVH band (mean ±1 standard deviation) represented 66.2±3.6% of all DVHs. Conclusion: A KBP model was developed and validated for radiotherapy of LA-NSCLC in a commercial treatment planning system. The clinical implementation may improve the consistency of IMRT/VMAT planning.

  20. Draft Site Treatment Plan (DSTP), Volumes I and II

    International Nuclear Information System (INIS)

    D'Amelio, J.

    1994-01-01

    Site Treatment Plans (STP) are required for facilities at which the DOE generates or stores mixed waste. This Draft Site Treatment Plan (DSTP) the second step in a three-phase process, identifies the currently preferred options for treating mixed waste at the Savannah River Site (SRS) or for developing treatment technologies where technologies do not exist or need modification. The DSTP reflects site-specific preferred options, developed with the state's input and based on existing available information. To the extent possible, the DSTP identifies specific treatment facilities for treating the mixed waste and proposes schedules. Where the selection of specific treatment facilities is not possible, schedules for alternative activities such as waste characterization and technology assessment are provided. All schedule and cost information presented is preliminary and is subject to change. The DSTP is comprised of two volumes: this Compliance Plan Volume and the Background Volume. This Compliance Plan Volume proposes overall schedules with target dates for achieving compliance with the land disposal restrictions (LDR) of RCRA and procedures for converting the target dates into milestones to be enforced under the Order. The more detailed discussion of the options contained in the Background Volume is provided for informational purposes only

  1. Valid and efficient manual estimates of intracranial volume from magnetic resonance images

    International Nuclear Information System (INIS)

    Klasson, Niklas; Olsson, Erik; Rudemo, Mats; Eckerström, Carl; Malmgren, Helge; Wallin, Anders

    2015-01-01

    Manual segmentations of the whole intracranial vault in high-resolution magnetic resonance images are often regarded as very time-consuming. Therefore it is common to only segment a few linearly spaced intracranial areas to estimate the whole volume. The purpose of the present study was to evaluate how the validity of intracranial volume estimates is affected by the chosen interpolation method, orientation of the intracranial areas and the linear spacing between them. Intracranial volumes were manually segmented on 62 participants from the Gothenburg MCI study using 1.5 T, T 1 -weighted magnetic resonance images. Estimates of the intracranial volumes were then derived using subsamples of linearly spaced coronal, sagittal or transversal intracranial areas from the same volumes. The subsamples of intracranial areas were interpolated into volume estimates by three different interpolation methods. The linear spacing between the intracranial areas ranged from 2 to 50 mm and the validity of the estimates was determined by comparison with the entire intracranial volumes. A progressive decrease in intra-class correlation and an increase in percentage error could be seen with increased linear spacing between intracranial areas. With small linear spacing (≤15 mm), orientation of the intracranial areas and interpolation method had negligible effects on the validity. With larger linear spacing, the best validity was achieved using cubic spline interpolation with either coronal or sagittal intracranial areas. Even at a linear spacing of 50 mm, cubic spline interpolation on either coronal or sagittal intracranial areas had a mean absolute agreement intra-class correlation with the entire intracranial volumes above 0.97. Cubic spline interpolation in combination with linearly spaced sagittal or coronal intracranial areas overall resulted in the most valid and robust estimates of intracranial volume. Using this method, valid ICV estimates could be obtained in less than five

  2. OCCUPATIONAL EDUCATION--PLANNING AND PROGRAMMING. VOLUME TWO.

    Science.gov (United States)

    KOTZ, ARNOLD

    ADDITIONAL POSITION PAPERS BASED ON INFORMATION GATHERED IN THE RECONNAISSANCE SURVEYS OF PLANNING AND PROGRAMING IN OCCUPATIONAL EDUCATION, REPORTED IN VOLUME ONE (VT 005 041), ARE PRESENTED. PART IV, CONCERNED WITH PROGRAM STRUCTURE AND BUDGETING AND THEIR RELATION TO THE PLANNING PROCESS, INCLUDES THE PAPERS--(1) "CURRENT POLICIES AND…

  3. On the validity of density overrides for VMAT lung SBRT planning

    International Nuclear Information System (INIS)

    Wiant, David; Vanderstraeten, Caroline; Maurer, Jacqueline; Pursley, Jan; Terrell, Jonathon; Sintay, Benjamin J.

    2014-01-01

    Purpose: Modeling dose to a moving target in lung is a very difficult task. Current approaches to planning lung stereotactic body radiotherapy (SBRT) generally calculate dose on either free breathing or average computed tomography (CT) scans, which do not always accurately predict dose to parts of the target volume not occupied by tumor on the planning scan. In this work, the authors look at using density overrides of the target volumes to more accurately predict dose for lung SBRT using the analytic anisotropic algorithm (AAA). Methods: Volumetric modulated arc therapy plans were created on free breathing scans (FBP), time average scans (AVGP), free breathing scans with the internal target volume overridden to tumor density (ITVP), free breathing scans with the planning target volume overridden to tumor density (PTVP), and free breathing scan using a hybrid scheme with the internal target volume set to tumor density and the planning target volume minus the internal target volume set to a density intermediate between lung and tumor (HP) for the case of a 4D motion phantom and five patient cases. Radiochromic film measurements were made for the phantom plans, with gamma analysis used to compare the planned to delivered dose. The patient plans were recalculated on each of the phases of a 4DCT to evaluate tumor coverage and conformity index (CI). A modified modulation complexity score (MCSv) and average open area per control point (AA) metrics were used to evaluate multileaf collimator (MLC) modulation for each of the plans. Results: The HP plans showed significantly higher gamma passing rates (p < 0.05) than the FBP, AVGP, and ITVP for criteria of 2 mm/2% and 1 mm/1%. No significant correlation was observed between gamma values and AA or MCSv. The tumor volume was covered by the prescription dose on all phases of the 4DCT for all patient plans. The PTVP and HP yielded lower mean CI than the other plans for all five patients, with three of the cases showing

  4. On the validity of density overrides for VMAT lung SBRT planning

    Energy Technology Data Exchange (ETDEWEB)

    Wiant, David, E-mail: david.wiant@conehealth.com; Vanderstraeten, Caroline; Maurer, Jacqueline; Pursley, Jan; Terrell, Jonathon; Sintay, Benjamin J. [Cone Health Cancer Center, Greensboro, North Carolina 27403 (United States)

    2014-08-15

    Purpose: Modeling dose to a moving target in lung is a very difficult task. Current approaches to planning lung stereotactic body radiotherapy (SBRT) generally calculate dose on either free breathing or average computed tomography (CT) scans, which do not always accurately predict dose to parts of the target volume not occupied by tumor on the planning scan. In this work, the authors look at using density overrides of the target volumes to more accurately predict dose for lung SBRT using the analytic anisotropic algorithm (AAA). Methods: Volumetric modulated arc therapy plans were created on free breathing scans (FBP), time average scans (AVGP), free breathing scans with the internal target volume overridden to tumor density (ITVP), free breathing scans with the planning target volume overridden to tumor density (PTVP), and free breathing scan using a hybrid scheme with the internal target volume set to tumor density and the planning target volume minus the internal target volume set to a density intermediate between lung and tumor (HP) for the case of a 4D motion phantom and five patient cases. Radiochromic film measurements were made for the phantom plans, with gamma analysis used to compare the planned to delivered dose. The patient plans were recalculated on each of the phases of a 4DCT to evaluate tumor coverage and conformity index (CI). A modified modulation complexity score (MCSv) and average open area per control point (AA) metrics were used to evaluate multileaf collimator (MLC) modulation for each of the plans. Results: The HP plans showed significantly higher gamma passing rates (p < 0.05) than the FBP, AVGP, and ITVP for criteria of 2 mm/2% and 1 mm/1%. No significant correlation was observed between gamma values and AA or MCSv. The tumor volume was covered by the prescription dose on all phases of the 4DCT for all patient plans. The PTVP and HP yielded lower mean CI than the other plans for all five patients, with three of the cases showing

  5. Limitations of the planning organ at risk volume (PRV) concept.

    Science.gov (United States)

    Stroom, Joep C; Heijmen, Ben J M

    2006-09-01

    Previously, we determined a planning target volume (PTV) margin recipe for geometrical errors in radiotherapy equal to M(T) = 2 Sigma + 0.7 sigma, with Sigma and sigma standard deviations describing systematic and random errors, respectively. In this paper, we investigated margins for organs at risk (OAR), yielding the so-called planning organ at risk volume (PRV). For critical organs with a maximum dose (D(max)) constraint, we calculated margins such that D(max) in the PRV is equal to the motion averaged D(max) in the (moving) clinical target volume (CTV). We studied margins for the spinal cord in 10 head-and-neck cases and 10 lung cases, each with two different clinical plans. For critical organs with a dose-volume constraint, we also investigated whether a margin recipe was feasible. For the 20 spinal cords considered, the average margin recipe found was: M(R) = 1.6 Sigma + 0.2 sigma with variations for systematic and random errors of 1.2 Sigma to 1.8 Sigma and -0.2 sigma to 0.6 sigma, respectively. The variations were due to differences in shape and position of the dose distributions with respect to the cords. The recipe also depended significantly on the volume definition of D(max). For critical organs with a dose-volume constraint, the PRV concept appears even less useful because a margin around, e.g., the rectum changes the volume in such a manner that dose-volume constraints stop making sense. The concept of PRV for planning of radiotherapy is of limited use. Therefore, alternative ways should be developed to include geometric uncertainties of OARs in radiotherapy planning.

  6. WE-B-304-02: Treatment Planning Evaluation and Optimization Should Be Biologically and Not Dose/volume Based

    International Nuclear Information System (INIS)

    Deasy, J.

    2015-01-01

    The ultimate goal of radiotherapy treatment planning is to find a treatment that will yield a high tumor control probability (TCP) with an acceptable normal tissue complication probability (NTCP). Yet most treatment planning today is not based upon optimization of TCPs and NTCPs, but rather upon meeting physical dose and volume constraints defined by the planner. It has been suggested that treatment planning evaluation and optimization would be more effective if they were biologically and not dose/volume based, and this is the claim debated in this month’s Point/Counterpoint. After a brief overview of biologically and DVH based treatment planning by the Moderator Colin Orton, Joseph Deasy (for biological planning) and Charles Mayo (against biological planning) will begin the debate. Some of the arguments in support of biological planning include: this will result in more effective dose distributions for many patients DVH-based measures of plan quality are known to have little predictive value there is little evidence that either D95 or D98 of the PTV is a good predictor of tumor control sufficient validated outcome prediction models are now becoming available and should be used to drive planning and optimization Some of the arguments against biological planning include: several decades of experience with DVH-based planning should not be discarded we do not know enough about the reliability and errors associated with biological models the radiotherapy community in general has little direct experience with side by side comparisons of DVH vs biological metrics and outcomes it is unlikely that a clinician would accept extremely cold regions in a CTV or hot regions in a PTV, despite having acceptable TCP values Learning Objectives: To understand dose/volume based treatment planning and its potential limitations To understand biological metrics such as EUD, TCP, and NTCP To understand biologically based treatment planning and its potential limitations

  7. Subseabed Disposal Program Plan. Volume II. FY80 budget and subtask work plans

    International Nuclear Information System (INIS)

    1980-01-01

    This volume of the Subseabed Disposal Program Plan presents a breakdown of the master program structure by major activity. Each activity is described and accompanied by a specific cost plan schedule and a milestone plan. The costs have been compiled in the Cost Plan Schedules attached to each Subtask Work Plan. The FY 1980 budget for the Subseabed Disposal Program is summarized at the second level of the Work Breakdown Structure. The milestone plans for FY 80 are presented. The milestones can be changed only with the concurrence of the Sandia Subseabed Program Manager

  8. Preliminary Validation and Verification Plan for CAREM Reactor Protection System

    International Nuclear Information System (INIS)

    Fittipaldi, Ana; Maciel Felix

    2000-01-01

    The purpose of this paper, is to present a preliminary validation and verification plan for a particular architecture proposed for the CAREM reactor protection system with software modules (computer based system).These software modules can be either own design systems or systems based in commercial modules such as programmable logic controllers (PLC) redundant of last generation.During this study, it was seen that this plan can also be used as a validation and verification plan of commercial products (COTS, commercial off the shelf) and/or smart transmitters.The software life cycle proposed and its features are presented, and also the advantages of the preliminary validation and verification plan

  9. International Photovoltaic Program Plan. Volume II. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Costello, D.; Koontz, R.; Posner, D.; Heiferling, P.; Carpenter, P.; Forman, S.; Perelman, L.

    1979-12-01

    This second volume of a two-part report on the International Photovoltaic Program Plan contains appendices summarizing the results of analyses conducted in preparation of the plan. These analyses include compilations of relevant statutes and existing Federal programs; strategies designed to expand the use of photovoltaics abroad; information on the domestic photovoltaic plan and its impact on the proposed international plan; perspectives on foreign competition; industry views on the international photovoltaic market and ideas about how US government actions could affect this market; international financing issues; and information on issues affecting foreign policy and developing countries.

  10. Some guidance on preparing validation plans for the DART Full System Models.

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Genetha Anne; Hough, Patricia Diane; Hills, Richard Guy (Sandia National Laboratories, Albuquerque, NM)

    2009-03-01

    Planning is an important part of computational model verification and validation (V&V) and the requisite planning document is vital for effectively executing the plan. The document provides a means of communicating intent to the typically large group of people, from program management to analysts to test engineers, who must work together to complete the validation activities. This report provides guidelines for writing a validation plan. It describes the components of such a plan and includes important references and resources. While the initial target audience is the DART Full System Model teams in the nuclear weapons program, the guidelines are generally applicable to other modeling efforts. Our goal in writing this document is to provide a framework for consistency in validation plans across weapon systems, different types of models, and different scenarios. Specific details contained in any given validation plan will vary according to application requirements and available resources.

  11. Integrated operations plan for the MFTF-B Mirror Fusion Test Facility. Volume I. Organization plan

    International Nuclear Information System (INIS)

    1981-12-01

    This plan and the accompanying MFTF-B Integrated Operations Plan are submitted in response to UC/LLNL Purchase Order 3883801, dated July 1981. The organization plan also addresses the specific tasks and trade studies directed by the scope of work. The Integrated Operations Plan, which includes a reliability, quality assurance, and safety plan and an integrated logistics plan, comprises the burden of the report. In the first section of this volume, certain underlying assumptions and observations are discussed setting the requirements and limits for organization. Section B presents the recommended structure itself. Section C Device Availability vs Maintenance and Support Efforts and Section D Staffing Levels and Skills provide backup detail and justification. Section E is a trade study on maintenance and support by LLNL staff vs subcontract and Section F is a plan for transitioning from the construction phase into operation. A brief summary of schedules and estimated costs concludes the volume

  12. Validation and verification plan for safety and PRA codes

    International Nuclear Information System (INIS)

    Ades, M.J.; Crowe, R.D.; Toffer, H.

    1991-04-01

    This report discusses a verification and validation (V ampersand V) plan for computer codes used for safety analysis and probabilistic risk assessment calculations. The present plan fulfills the commitments by Westinghouse Savannah River Company (WSRC) to the Department of Energy Savannah River Office (DOE-SRO) to bring the essential safety analysis and probabilistic risk assessment codes in compliance with verification and validation requirements

  13. Approved Site Treatment Plan, Volumes 1 and 2. Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Helmich, E.H.; Molen, G.; Noller, D.

    1996-03-22

    The US Department of Energy, Savannah River Operations Office (DOE-SR), has prepared the Site Treatment Plan (STP) for Savannah River Site (SRS) mixed wastes in accordance with RCRA Section 3021(b), and SCDHEC has approved the STP (except for certain offsite wastes) and issued an order enforcing the STP commitments in Volume 1. DOE-SR and SCDHEC agree that this STP fulfills the requirements contained in the FFCAct, RCRA Section 3021, and therefore, pursuant to Section 105(a) of the FFCAct (RCRA Section 3021(b)(5)), DOE`s requirements are to implement the plan for the development of treatment capacities and technologies pursuant to RCRA Section 3021. Emerging and new technologies not yet considered may be identified to manage waste more safely, effectively, and at lower cost than technologies currently identified in the plan. DOE will continue to evaluate and develop technologies that offer potential advantages in public acceptance, privatization, consolidation, risk abatement, performance, and life-cycle cost. Should technologies that offer such advantages be identified, DOE may request a revision/modification of the STP in accordance with the provisions of Consent Order 95-22-HW. The Compliance Plan Volume (Volume 1) identifies project activity schedule milestones for achieving compliance with Land Disposal Restrictions (LDR). Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume 2) and is provided for information.

  14. Approved Site Treatment Plan, Volumes 1 and 2. Revision 4

    International Nuclear Information System (INIS)

    Helmich, E.H.; Molen, G.; Noller, D.

    1996-01-01

    The US Department of Energy, Savannah River Operations Office (DOE-SR), has prepared the Site Treatment Plan (STP) for Savannah River Site (SRS) mixed wastes in accordance with RCRA Section 3021(b), and SCDHEC has approved the STP (except for certain offsite wastes) and issued an order enforcing the STP commitments in Volume 1. DOE-SR and SCDHEC agree that this STP fulfills the requirements contained in the FFCAct, RCRA Section 3021, and therefore, pursuant to Section 105(a) of the FFCAct (RCRA Section 3021(b)(5)), DOE's requirements are to implement the plan for the development of treatment capacities and technologies pursuant to RCRA Section 3021. Emerging and new technologies not yet considered may be identified to manage waste more safely, effectively, and at lower cost than technologies currently identified in the plan. DOE will continue to evaluate and develop technologies that offer potential advantages in public acceptance, privatization, consolidation, risk abatement, performance, and life-cycle cost. Should technologies that offer such advantages be identified, DOE may request a revision/modification of the STP in accordance with the provisions of Consent Order 95-22-HW. The Compliance Plan Volume (Volume 1) identifies project activity schedule milestones for achieving compliance with Land Disposal Restrictions (LDR). Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume 2) and is provided for information

  15. Verification and validation guidelines for high integrity systems. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, H.; Hecht, M.; Dinsmore, G.; Hecht, S.; Tang, D. [SoHaR, Inc., Beverly Hills, CA (United States)

    1995-03-01

    High integrity systems include all protective (safety and mitigation) systems for nuclear power plants, and also systems for which comparable reliability requirements exist in other fields, such as in the process industries, in air traffic control, and in patient monitoring and other medical systems. Verification aims at determining that each stage in the software development completely and correctly implements requirements that were established in a preceding phase, while validation determines that the overall performance of a computer system completely and correctly meets system requirements. Volume I of the report reviews existing classifications for high integrity systems and for the types of errors that may be encountered, and makes recommendations for verification and validation procedures, based on assumptions about the environment in which these procedures will be conducted. The final chapter of Volume I deals with a framework for standards in this field. Volume II contains appendices dealing with specific methodologies for system classification, for dependability evaluation, and for two software tools that can automate otherwise very labor intensive verification and validation activities.

  16. Verification and validation guidelines for high integrity systems. Volume 1

    International Nuclear Information System (INIS)

    Hecht, H.; Hecht, M.; Dinsmore, G.; Hecht, S.; Tang, D.

    1995-03-01

    High integrity systems include all protective (safety and mitigation) systems for nuclear power plants, and also systems for which comparable reliability requirements exist in other fields, such as in the process industries, in air traffic control, and in patient monitoring and other medical systems. Verification aims at determining that each stage in the software development completely and correctly implements requirements that were established in a preceding phase, while validation determines that the overall performance of a computer system completely and correctly meets system requirements. Volume I of the report reviews existing classifications for high integrity systems and for the types of errors that may be encountered, and makes recommendations for verification and validation procedures, based on assumptions about the environment in which these procedures will be conducted. The final chapter of Volume I deals with a framework for standards in this field. Volume II contains appendices dealing with specific methodologies for system classification, for dependability evaluation, and for two software tools that can automate otherwise very labor intensive verification and validation activities

  17. MARS Validation Plan and Status

    International Nuclear Information System (INIS)

    Ahn, Seung-hoon; Cho, Yong-jin

    2008-01-01

    The KINS Reactor Thermal-hydraulic Analysis System (KINS-RETAS) under development is directed toward a realistic analysis approach of best-estimate (BE) codes and realistic assumptions. In this system, MARS is pivoted to provide the BE Thermal-Hydraulic (T-H) response in core and reactor coolant system to various operational transients and accidental conditions. As required for other BE codes, the qualification is essential to ensure reliable and reasonable accuracy for a targeted MARS application. Validation is a key element of the code qualification, and determines the capability of a computer code in predicting the major phenomena expected to occur. The MARS validation was made by its developer KAERI, on basic premise that its backbone code RELAP5/MOD3.2 is well qualified against analytical solutions, test or operational data. A screening was made to select the test data for MARS validation; some models transplanted from RELAP5, if already validated and found to be acceptable, were screened out from assessment. It seems to be reasonable, but does not demonstrate whether code adequacy complies with the software QA guidelines. Especially there may be much difficulty in validating the life-cycle products such as code updates or modifications. This paper presents the plan for MARS validation, and the current implementation status

  18. Optimized Planning Target Volume for Intact Cervical Cancer

    International Nuclear Information System (INIS)

    Khan, Alvin; Jensen, Lindsay G.; Sun Shuai; Song, William Y.; Yashar, Catheryn M.; Mundt, Arno J.; Zhang Fuquan; Jiang, Steve B.; Mell, Loren K.

    2012-01-01

    Purpose: To model interfraction clinical target volume (CTV) variation in patients with intact cervical cancer and design a planning target volume (PTV) that minimizes normal tissue dose while maximizing CTV coverage. Methods and Materials: We analyzed 50 patients undergoing external-beam radiotherapy for intact cervical cancer using daily online cone-beam computed tomography (CBCT). The CBCTs (n = 972) for each patient were rigidly registered to the planning CT. The CTV was delineated on the planning CT (CTV 0 ) and the set of CBCTs ({CTV 1 –CTV 25 }). Manual (n = 98) and automated (n = 668) landmarks were placed over the surface of CTV 0 with reference to defined anatomic structures. Normal vectors were extended from each landmark, and the minimum length required for a given probability of encompassing CTV 1 –CTV 25 was computed. The resulting expansions were used to generate an optimized PTV. Results: The mean (SD; range) normal vector length to ensure 95% coverage was 4.3 mm (2.7 mm; 1–16 mm). The uniform expansion required to ensure 95% probability of CTV coverage was 13 mm. An anisotropic margin of 20 mm anteriorly and posteriorly and 10 mm superiorly, inferiorly, and laterally also would have ensured a 95% probability of CTV coverage. The volume of the 95% optimized PTV (1470 cm 3 ) was significantly lower than both the anisotropic PTV (2220 cm 3 ) and the uniformly expanded PTV (2110 cm 3 ) (p 0 , 5–10 mm along the interfaces of CTV 0 with the bladder and rectum, and 10–14 mm along the anterior surface of CTV 0 at the level of the uterus. Conclusion: Optimizing PTV definition according to surface landmarking resulted in a high probability of CTV coverage with reduced PTV volumes. Our results provide data justifying planning margins to use in practice and clinical trials.

  19. CASL Verification and Validation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Mousseau, Vincent Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dinh, Nam [North Carolina State Univ., Raleigh, NC (United States)

    2016-06-30

    This report documents the Consortium for Advanced Simulation of LWRs (CASL) verification and validation plan. The document builds upon input from CASL subject matter experts, most notably the CASL Challenge Problem Product Integrators, CASL Focus Area leaders, and CASL code development and assessment teams. This document will be a living document that will track progress on CASL to do verification and validation for both the CASL codes (including MPACT, CTF, BISON, MAMBA) and for the CASL challenge problems (CIPS, PCI, DNB). The CASL codes and the CASL challenge problems are at differing levels of maturity with respect to validation and verification. The gap analysis will summarize additional work that needs to be done. Additional VVUQ work will be done as resources permit. This report is prepared for the Department of Energy’s (DOE’s) CASL program in support of milestone CASL.P13.02.

  20. DNFSB Recommendation 94-1 Hanford Site Integrated Stabilization Management Plan. Volume 2

    International Nuclear Information System (INIS)

    Gerber, E.W.

    1995-10-01

    The Hanford Site Integrated Stabilization Management Plan (SISMP) was developed in support of the US Department of Energy's (DOE) Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 94-1 Integrated Program Plan (IPP). Volume 1 of the SISMP identifies the technical scope and costs associated with Hanford Site plans to resolve concerns identified in DNFSB Recommendation 94-1. Volume 2 of the SISMP provides the Resource Loaded Integrated Schedules for Spent Nuclear Fuel Project and Plutonium Finishing Plant activities identified in Volume 1 of the SISMP. Appendix A provides the schedules and progress curves related to spent nuclear fuel management. Appendix B provides the schedules and progress curves related to plutonium-bearing material management. Appendix C provides programmatic logic diagrams that were referenced in Volume 1 of the SISMP

  1. Split-Volume Treatment Planning of Multiple Consecutive Vertebral Body Metastases for Cyberknife Image-Guided Robotic Radiosurgery

    International Nuclear Information System (INIS)

    Sahgal, Arjun; Chuang, Cynthia; Larson, David; Huang, Kim; Petti, Paula; Weinstein, Phil; Ma Lijun

    2008-01-01

    Cyberknife treatment planning of multiple consecutive vertebral body metastases is challenging due to large target volumes adjacent to critical normal tissues. A split-volume treatment planning technique was developed to improve the treatment plan quality of such lesions. Treatment plans were generated for 1 to 5 consecutive thoracic vertebral bodies (CVBM) prescribing a total dose of 24 Gy in 3 fractions. The planning target volume (PTV) consisted of the entire vertebral body(ies). Treatment plans were generated considering both the de novo clinical scenario (no prior radiation), imposing a dose limit of 8 Gy to 1 cc of spinal cord, and the retreatment scenario (prior radiation) with a dose limit of 3 Gy to 1 cc of spinal cord. The split-volume planning technique was compared with the standard full-volume technique only for targets ranging from 2 to 5 CVBM in length. The primary endpoint was to obtain best PTV coverage by the 24 Gy prescription isodose line. A total of 18 treatment plans were generated (10 standard and 8 split-volume). PTV coverage by the 24-Gy isodose line worsened consistently as the number of CVBM increased for both the de novo and retreatment scenario. Split-volume planning was achieved by introducing a 0.5-cm gap, splitting the standard full-volume PTV into 2 equal length PTVs. In every case, split-volume planning resulted in improved PTV coverage by the 24-Gy isodose line ranging from 4% to 12% for the de novo scenario and, 8% to 17% for the retreatment scenario. We did not observe a significant trend for increased monitor units required, or higher doses to spinal cord or esophagus, with split-volume planning. Split-volume treatment planning significantly improves Cyberknife treatment plan quality for CVBM, as compared to the standard technique. This technique may be of particular importance in clinical situations where stringent spinal cord dose limits are required

  2. Volume rendering in treatment planning for moving targets

    Energy Technology Data Exchange (ETDEWEB)

    Gemmel, Alexander [GSI-Biophysics, Darmstadt (Germany); Massachusetts General Hospital, Boston (United States); Wolfgang, John A.; Chen, George T.Y. [Massachusetts General Hospital, Boston (United States)

    2009-07-01

    Advances in computer technologies have facilitated the development of tools for 3-dimensional visualization of CT-data sets with volume rendering. The company Fovia has introduced a high definition volume rendering engine (HDVR trademark by Fovia Inc., Palo Alto, USA) that is capable of representing large CT data sets with high user interactivity even on standard PCs. Fovia provides a software development kit (SDK) that offers control of all the features of the rendering engine. We extended the SDK by functionalities specific to the task of treatment planning for moving tumors. This included navigation of the patient's anatomy in beam's eye view, fast point-and-click measurement of lung tumor trajectories as well as estimation of range perturbations due to motion by calculation of (differential) water equivalent path lengths for protons and carbon ions on 4D-CT data sets. We present patient examples to demonstrate the advantages and disadvantages of volume rendered images as compared to standard 2-dimensional axial plane images. Furthermore, we show an example of a range perturbation analysis. We conclude that volume rendering is a powerful technique for the representation and analysis of large time resolved data sets in treatment planning.

  3. A broad scope knowledge based model for optimization of VMAT in esophageal cancer: validation and assessment of plan quality among different treatment centers

    International Nuclear Information System (INIS)

    Fogliata, Antonella; Nicolini, Giorgia; Clivio, Alessandro; Vanetti, Eugenio; Laksar, Sarbani; Tozzi, Angelo; Scorsetti, Marta; Cozzi, Luca

    2015-01-01

    To evaluate the performance of a broad scope model-based optimisation process for volumetric modulated arc therapy applied to esophageal cancer. A set of 70 previously treated patients in two different institutions, were selected to train a model for the prediction of dose-volume constraints. The model was built with a broad-scope purpose, aiming to be effective for different dose prescriptions and tumour localisations. It was validated on three groups of patients from the same institution and from another clinic not providing patients for the training phase. Comparison of the automated plans was done against reference cases given by the clinically accepted plans. Quantitative improvements (statistically significant for the majority of the analysed dose-volume parameters) were observed between the benchmark and the test plans. Of 624 dose-volume objectives assessed for plan evaluation, in 21 cases (3.3 %) the reference plans failed to respect the constraints while the model-based plans succeeded. Only in 3 cases (<0.5 %) the reference plans passed the criteria while the model-based failed. In 5.3 % of the cases both groups of plans failed and in the remaining cases both passed the tests. Plans were optimised using a broad scope knowledge-based model to determine the dose-volume constraints. The results showed dosimetric improvements when compared to the benchmark data. Particularly the plans optimised for patients from the third centre, not participating to the training, resulted in superior quality. The data suggests that the new engine is reliable and could encourage its application to clinical practice. The online version of this article (doi:10.1186/s13014-015-0530-5) contains supplementary material, which is available to authorized users

  4. Man-in-the-loop validation plan for the Millstone Unit 3 SPDS

    International Nuclear Information System (INIS)

    Blanch, P.M.; Wilkinson, C.D.

    1985-01-01

    This paper describes the man-in-the-loop validation plan for the Millstone Point Unit 3 (MP3) Safety Parameter Display System (SPDS). MP3 is a pressurized water reactor scheduled to load fuel November, 1985. The SPDS is being implemented as part of plant construction. This paper provides an overview of the validation process. Detailed validation procedures, scenarios, and evaluation forms will be incorporated into the validation plan to produce the detailed validation program. The program document will provide all of the new detailed instructions necessary to perform the man-in-the-loop validation

  5. Temporal validation for landsat-based volume estimation model

    Science.gov (United States)

    Renaldo J. Arroyo; Emily B. Schultz; Thomas G. Matney; David L. Evans; Zhaofei Fan

    2015-01-01

    Satellite imagery can potentially reduce the costs and time associated with ground-based forest inventories; however, for satellite imagery to provide reliable forest inventory data, it must produce consistent results from one time period to the next. The objective of this study was to temporally validate a Landsat-based volume estimation model in a four county study...

  6. Volume definition system for treatment planning

    International Nuclear Information System (INIS)

    Alakuijala, Jyrki; Pekkarinen, Ari; Puurunen, Harri

    1997-01-01

    Purpose: Volume definition is a difficult and time consuming task in 3D treatment planning. We have studied a systems approach for constructing an efficient and reliable set of tools for volume definition. Our intent is to automate body outline, air cavities and bone volume definition and accelerate definition of other anatomical structures. An additional focus is on assisting in definition of CTV and PTV. The primary goals of this work are to cut down the time used in contouring and to improve the accuracy of volume definition. Methods: We used the following tool categories: manual, semi-automatic, automatic, structure management, target volume definition, and visualization tools. The manual tools include mouse contouring tools with contour editing possibilities and painting tools with a scaleable circular brush and an intelligent brush. The intelligent brush adapts its shape to CT value boundaries. The semi-automatic tools consist of edge point chaining, classical 3D region growing of single segment and competitive volume growing of multiple segments. We tuned the volume growing function to take into account both local and global region image values, local volume homogeneity, and distance. Heuristic seeding followed with competitive volume growing finds the body outline, couch and air automatically. The structure management tool stores ICD-O coded structures in a database. The codes have predefined volume growing parameters and thus are able to accommodate the volume growing dissimilarity function for different volume types. The target definition tools include elliptical 3D automargin for CTV to PTV transformation and target volume interpolation and extrapolation by distance transform. Both the CTV and the PTV can overlap with anatomical structures. Visualization tools show the volumes as contours or color wash overlaid on an image and displays voxel rendering or translucent triangle mesh rendering in 3D. Results: The competitive volume growing speeds up the

  7. Sensitivity and uncertainty analyses applied to criticality safety validation. Volume 2

    International Nuclear Information System (INIS)

    Broadhead, B.L.; Hopper, C.M.; Parks, C.V.

    1999-01-01

    This report presents the application of sensitivity and uncertainty (S/U) analysis methodologies developed in Volume 1 to the code/data validation tasks of a criticality safety computational study. Sensitivity and uncertainty analysis methods were first developed for application to fast reactor studies in the 1970s. This work has revitalized and updated the existing S/U computational capabilities such that they can be used as prototypic modules of the SCALE code system, which contains criticality analysis tools currently in use by criticality safety practitioners. After complete development, simplified tools are expected to be released for general use. The methods for application of S/U and generalized linear-least-square methodology (GLLSM) tools to the criticality safety validation procedures were described in Volume 1 of this report. Volume 2 of this report presents the application of these procedures to the validation of criticality safety analyses supporting uranium operations where enrichments are greater than 5 wt %. Specifically, the traditional k eff trending analyses are compared with newly developed k eff trending procedures, utilizing the D and c k coefficients described in Volume 1. These newly developed procedures are applied to a family of postulated systems involving U(11)O 2 fuel, with H/X values ranging from 0--1,000. These analyses produced a series of guidance and recommendations for the general usage of these various techniques. Recommendations for future work are also detailed

  8. Northwest conservation and electric power plan 1986. Volume I

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This 20 year plan is prepared in accordance with the Pacific Northwest Electric Power Planning and Conservation Act - Public Law 96-501, of 1980. This Act required the Council to develop and adopt a 20-year electrical power plan for the region with a program to protect, mitigate and enhance the fish and wildlife affected by hydroelectric development in the Columbia River Basin. The plan provides a 25 year history of the regions power development and comments on its unique features and changing nature. Presentations covers problems, solutions and the planning strategy for risk management. The existing electrical power system is discussed along with future electricity needs, generating resources, conservation of resources, regional needs and resources, and the 1986 action plan. Underlying details are provided in Volume II

  9. Validation of a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial HDR brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Eric; Beaulieu, Luc, E-mail: Luc.Beaulieu@phy.ulaval.ca [Département de Physique, de Génie Physique et d’optique et Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, Québec G1V 0A6, Canada and Département de Radio-oncologie et Axe Oncologie du Centre de Recherche du CHU de Québec, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Gardi, Lori; Barker, Kevin; Montreuil, Jacques; Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada)

    2015-12-15

    Purpose: In current clinical practice, there is no integrated 3D ultrasound (3DUS) guidance system clinically available for breast brachytherapy. In this study, the authors present a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial high dose rate (HDR) brachytherapy treatment. Methods: For this work, a new computer controlled robotic 3DUS system was built to perform a hybrid motion scan, which is a combination of a 6 cm linear translation with a 30° rotation at both ends. The new 3DUS scanner was designed to fit on a modified Kuske assembly, keeping the current template grid configuration but modifying the frame to allow the mounting of the 3DUS system at several positions. A finer grid was also tested. A user interface was developed to perform image reconstruction, semiautomatic segmentation of the surgical bed as well as catheter reconstruction and tracking. A 3D string phantom was used to validate the geometric accuracy of the reconstruction. The volumetric accuracy of the system was validated with phantoms using magnetic resonance imaging (MRI) and computed tomography (CT) images. In order to accurately determine whether 3DUS can effectively replace CT for treatment planning, the authors have compared the 3DUS catheter reconstruction to the one obtained from CT images. In addition, in agarose-based phantoms, an end-to-end procedure was performed by executing six independent complete procedures with both 14 and 16 catheters, and for both standard and finer Kuske grids. Finally, in phantoms, five end-to-end procedures were performed with the final CT planning for the validation of 3DUS preplanning. Results: The 3DUS acquisition time is approximately 10 s. A paired Student t-test showed that there was no statistical significant difference between known and measured values of string separations in each direction. Both MRI and CT volume measurements were not statistically different from 3DUS volume (Student t-test: p > 0

  10. A patient-specific planning target volume used in 'plan of the day' adaptation for interfractional motion mitigation

    International Nuclear Information System (INIS)

    Chen, Wenjing; Gemmel, Alexander; Rietzel, Eike

    2013-01-01

    We propose a patient-specific planning target volume (PTV) to deal with interfractional variations, and test its feasibility in a retrospective treatment-planning study. Instead of using one planning image only, multiple scans are taken on different days. The target and organs at risk (OARs) are delineated on each images. The proposed PTV is generated from a union of those target contours on the planning images, excluding voxels of the OARs, and is denoted the PTV 'GP-OAR' (global prostate-organs at risk). The study is performed using 'plan of the day' adaptive workflow, which selects a daily plan from a library of plans based on a similarity comparison between the daily scan and planning images. The daily plans optimized for GP-OAR volumes are compared with those optimized for PTVs generated from a single prostate contour (PTV SP). Four CT serials of prostate cancer patient datasets are included in the test, and in total 28 fractions are simulated. The results show that the daily chosen GP-OAR plans provide excellent target coverage, with V95 values of the prostate mostly >95%. In addition, dose delivered to the OARs as calculated from applying daily chosen GP-OAR plans is slightly increased but comparable to that calculated from applying daily SP plans. In general, the PTV GP-OARs are able to cover possible target variations while keeping dose delivered to the OARs at a similar level to that of the PTV SPs. (author)

  11. The development and validation of the advance care planning questionnaire in Malaysia.

    Science.gov (United States)

    Lai, Pauline Siew Mei; Mohd Mudri, Salinah; Chinna, Karuthan; Othman, Sajaratulnisah

    2016-10-18

    Advance care planning is a voluntary process whereby individual preferences, values and beliefs are used to aid a person in planning for end-of-life care. Currently, there is no local instrument to assess an individual's awareness and attitude towards advance care planning. This study aimed to develop an Advance Care Planning Questionnaire and to determine its validity and reliability among older people in Malaysia. The Advance Care Planning Questionnaire was developed based on literature review. Face and content validity was verified by an expert panel, and piloted among 15 participants. Our study was conducted from October 2013 to February 2014, at an urban primary care clinic in Malaysia. Included were those aged >50 years, who could understand English. A retest was conducted 2 weeks after the first administration. Participants from the pilot study did not encounter any problems in answering the Advance Care Planning Questionnaire. Hence, no further modifications were made. Flesch reading ease was 71. The final version of the Advance Care Planning Questionnaire consists of 66 items: 30 items were measured on a nominal scale, whilst 36 items were measured on a Likert-like scale; of which we were only able to validate 22 items, as the remaining 14 items were descriptive in nature. A total of 245 eligible participants were approached; of which 230 agreed to participate (response rate = 93.9 %). Factor analysis on the 22 items measured on a Likert-scale revealed four domains: "feelings regarding advance care planning", "justifications for advance care planning", "justifications for not having advance care planning: fate and religion", and "justifications for not having advance care planning: avoid thinking about death". The Cronbach's alpha values for items each domain ranged from 0.637-0.915. In test-retest, kappa values ranged from 0.738-0.947. The final Advance Care Planning Questionnaire consisted of 63 items and 4 domains. It was found to be a valid and

  12. Marketing Plan for Demonstration and Validation Assets

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2008-05-30

    The National Security Preparedness Project (NSPP), is to be sustained by various programs, including technology demonstration and evaluation (DEMVAL). This project assists companies in developing technologies under the National Security Technology Incubator program (NSTI) through demonstration and validation of technologies applicable to national security created by incubators and other sources. The NSPP also will support the creation of an integrated demonstration and validation environment. This report documents the DEMVAL marketing and visibility plan, which will focus on collecting information about, and expanding the visibility of, DEMVAL assets serving businesses with national security technology applications in southern New Mexico.

  13. Pathology-based validation of FDG PET segmentation tools for volume assessment of lymph node metastases from head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Schinagl, Dominic A.X. [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands); Radboud University Nijmegen Medical Centre, Department of Radiation Oncology (874), P.O. Box 9101, Nijmegen (Netherlands); Span, Paul N.; Kaanders, Johannes H.A.M. [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands); Hoogen, Frank J.A. van den [Radboud University Nijmegen Medical Centre, Department of Otorhinolaryngology, Head and Neck Surgery, Nijmegen (Netherlands); Merkx, Matthias A.W. [Radboud University Nijmegen Medical Centre, Department of Oral and Maxillofacial Surgery, Nijmegen (Netherlands); Slootweg, Piet J. [Radboud University Nijmegen Medical Centre, Department of Pathology, Nijmegen (Netherlands); Oyen, Wim J.G. [Radboud University Nijmegen Medical Centre, Department of Nuclear Medicine, Nijmegen (Netherlands)

    2013-12-15

    FDG PET is increasingly incorporated into radiation treatment planning of head and neck cancer. However, there are only limited data on the accuracy of radiotherapy target volume delineation by FDG PET. The purpose of this study was to validate FDG PET segmentation tools for volume assessment of lymph node metastases from head and neck cancer against the pathological method as the standard. Twelve patients with head and neck cancer and 28 metastatic lymph nodes eligible for therapeutic neck dissection underwent preoperative FDG PET/CT. The metastatic lymph nodes were delineated on CT (Node{sub CT}) and ten PET segmentation tools were used to assess FDG PET-based nodal volumes: interpreting FDG PET visually (PET{sub VIS}), applying an isocontour at a standardized uptake value (SUV) of 2.5 (PET{sub SUV}), two segmentation tools with a fixed threshold of 40 % and 50 %, and two adaptive threshold based methods. The latter four tools were applied with the primary tumour as reference and also with the lymph node itself as reference. Nodal volumes were compared with the true volume as determined by pathological examination. Both Node{sub CT} and PET{sub VIS} showed good correlations with the pathological volume. PET segmentation tools using the metastatic node as reference all performed well but not better than PET{sub VIS}. The tools using the primary tumour as reference correlated poorly with pathology. PET{sub SUV} was unsatisfactory in 35 % of the patients due to merging of the contours of adjacent nodes. FDG PET accurately estimates metastatic lymph node volume, but beyond the detection of lymph node metastases (staging), it has no added value over CT alone for the delineation of routine radiotherapy target volumes. If FDG PET is used in radiotherapy planning, treatment adaptation or response assessment, we recommend an automated segmentation method for purposes of reproducibility and interinstitutional comparison. (orig.)

  14. Savannah River Site Environmental Implementation Plan. Volume 2, Protection programs

    Energy Technology Data Exchange (ETDEWEB)

    1989-08-01

    Formal sitewide environmental planning at the . Savannah River Site (SRS) began in 1986 with the development and adoption of the Strategic Environmental Plan. The Strategic Environmental Plan describes the philosophy, policy, and overall program direction of environmental programs for the operation of the SRS. The Strategic Environmental Plan (Volume 2) provided the basis for development of the Environmental Implementation Plan (EIP). The EIP is the detailed, comprehensive environmental master plan for operating contractor organizations at the SRS. The EIP provides a process to ensure that all environmental requirements and obligations are being met by setting specific measurable goals and objectives and strategies for implementation. The plan is the basis for justification of site manpower and funding requests for environmental projects and programs over a five-year planning period.

  15. Validation of Fully Automated VMAT Plan Generation for Library-Based Plan-of-the-Day Cervical Cancer Radiotherapy

    OpenAIRE

    Sharfo, Abdul Wahab M.; Breedveld, Sebastiaan; Voet, Peter W. J.; Heijkoop, Sabrina T.; Mens, Jan-Willem M.; Hoogeman, Mischa S.; Heijmen, Ben J. M.

    2016-01-01

    textabstractPurpose: To develop and validate fully automated generation of VMAT plan-libraries for plan-of-the-day adaptive radiotherapy in locally-advanced cervical cancer. Material and Methods: Our framework for fully automated treatment plan generation (Erasmus-iCycle) was adapted to create dual-arc VMAT treatment plan libraries for cervical cancer patients. For each of 34 patients, automatically generated VMAT plans (autoVMAT) were compared to manually generated, clinically delivered 9-be...

  16. Savannah River Site Approved Site Treatment Plan, 2001 Annual Update (Volumes I and II)

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, B.

    2001-04-30

    The Compliance Plan Volume (Volume I) identifies project activity scheduled milestones for achieving compliance with Land Disposal Restrictions. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume II) and is provided for information.

  17. NCTPlan. The new PC version of MacNCTPlan improvements and validation of the treatment planning system

    International Nuclear Information System (INIS)

    Gonzalez, S.J.; Santa Cruz, Gustavo A.; Yam, C.S.

    2003-01-01

    Full text: The treatment planning system that has been used routinely in phase-I clinical trials of BNCT at Harvard/MIT consists of the MacNCTPlan interactive planning software coupled to the MCNP 4B Monte Carlo radiation transport code. The physical and mathematical principles of MacNCTPlan as well as its architecture, operation and application have been previously described elsewhere. The use of this software in clinical trials together with a detailed analysis of the code led to the identification of some limitations and deficiencies. The motivation for this PC version, Neutron Capture Therapy Planning, relies basically in two major reasons: the need to integrate the different steps for making a plan and the need to improve some features of the Macintosh version. NCTPlan aims to reproduce all the features and capabilities present in the Macintosh version. Working on this, some deficiencies were corrected and several changes in the interface were performed in order to provide a more friendly and reliable program. Among the changes intended to facilitate the treatment planning process, the most important are the integration of the auxiliary program MPREP to NCTPlan and a great improvement in the visualization of isodose contours. NCTPlan has the ability to show the isodose distributions superimposed on two orthogonal planes of the CT volume, these planes being updated in real time as the orientation of the planes is changed. The major modifications to the mathematical algorithms concerned the material assignment in the geometric model, dose distribution calculations and three-dimensional dose-volume histogram (DVH) derivation. Therefore, NCTPlan provides a user-friendly interface thanks to the integration of the different steps involved in treatment planning. Complete control of the MCNP radiation transport code is under study. Cross-validation of NCTPlan against reference calculations made apparent the improvements performed on the mathematical algorithms

  18. Validation of equations for pleural effusion volume estimation by ultrasonography.

    Science.gov (United States)

    Hassan, Maged; Rizk, Rana; Essam, Hatem; Abouelnour, Ahmed

    2017-12-01

    To validate the accuracy of previously published equations that estimate pleural effusion volume using ultrasonography. Only equations using simple measurements were tested. Three measurements were taken at the posterior axillary line for each case with effusion: lateral height of effusion ( H ), distance between collapsed lung and chest wall ( C ) and distance between lung and diaphragm ( D ). Cases whose effusion was aspirated to dryness were included and drained volume was recorded. Intra-class correlation coefficient (ICC) was used to determine the predictive accuracy of five equations against the actual volume of aspirated effusion. 46 cases with effusion were included. The most accurate equation in predicting effusion volume was ( H  +  D ) × 70 (ICC 0.83). The simplest and yet accurate equation was H  × 100 (ICC 0.79). Pleural effusion height measured by ultrasonography gives a reasonable estimate of effusion volume. Incorporating distance between lung base and diaphragm into estimation improves accuracy from 79% with the first method to 83% with the latter.

  19. Dosimetric impact of the variation of the prostate volume and shape between pretreatment planning and treatment procedure

    International Nuclear Information System (INIS)

    Beaulieu, Luc; Aubin, Sylviane; Taschereau, Richard; Pouliot, Jean; Vigneault, Eric

    2002-01-01

    Purpose: The goal of this study is to evaluate the dosimetric impact on a pretreatment planning of prostatic volume and shape variations occurring between the moment of the volume study (preplanning) and just before a transperineal permanent seed implant procedure. Such variations could be an obvious source of misplacement of the seeds relative to the prostate gland and organs at risk. Other sources of dosimetric uncertainties, such as misplacement due to the procedure itself or edema, are eliminated by looking at these variations before the implant procedure. Methods and Materials: For 35 clinical cases, prostate contours were taken at preplanning time as well as in the operating room (OR) minutes before the procedure. Comparison of shape and volume between the two sets was made. The impact on V100 was evaluated by placing the seeds in their planned positions in the new volume (clinical situation) and also by performing a new plan with the second set of contours to simulate an intraoperative approach. Results: The volume taken in the OR remained unchanged compared to the pretreatment planning volume in only 37% of the cases. While on average the dose coverage loss from pretreatment planning due to a combination of variations of volume and shape was small at 5.7%, a V100 degradation of up to 20.9% was observed in extreme cases. Even in cases in which no changes in volume were observed, changes in shape occurred and strongly affected implant dosimetry. Conclusions: Variations of volume and shape between pretreatment planning and the implant procedure can have a strong impact on the dosimetry if the planning and the implant procedure are not performed on the same day. This is an argument in favor of performing implant dosimetry in the OR

  20. The minimum knowledge base for predicting organ-at-risk dose-volume levels and plan-related complications in IMRT planning

    International Nuclear Information System (INIS)

    Zhang, Hao H; D'Souza, Warren D; Meyer, Robert R; Shi Leyuan

    2010-01-01

    IMRT treatment planning requires consideration of two competing objectives: achieving the required amount of radiation for the planning target volume and minimizing the amount of radiation delivered to all other tissues. It is important for planners to understand the tradeoff between competing factors so that the time-consuming human interaction loop (plan-evaluate-modify) can be eliminated. Treatment-plan-surface models have been proposed as a decision support tool to aid treatment planners and clinicians in choosing between rival treatment plans in a multi-plan environment. In this paper, an empirical approach is introduced to determine the minimum number of treatment plans (minimum knowledge base) required to build accurate representations of the IMRT plan surface in order to predict organ-at-risk (OAR) dose-volume (DV) levels and complications as a function of input DV constraint settings corresponding to all involved OARs in the plan. We have tested our approach on five head and neck patients and five whole pelvis/prostate patients. Our results suggest that approximately 30 plans were sufficient to predict DV levels with less than 3% relative error in both head and neck and whole pelvis/prostate cases. In addition, approximately 30-60 plans were sufficient to predict saliva flow rate with less than 2% relative error and to classify rectal bleeding with an accuracy of 90%.

  1. KNGR core proection calculator, software, verification and validation plan

    International Nuclear Information System (INIS)

    Kim, Jang Yeol; Park, Jong Kyun; Lee, Ki Young; Lee, Jang Soo; Cheon, Se Woo

    2001-05-01

    This document describes the Software Verification and Validation Plan(SVVP) Guidance to be used in reviewing the Software Program Manual(SPM) in Korean Next Generation Reactor(KNGR) projects. This document is intended for a verifier or reviewer who is involved with performing of software verification and validation task activity in KNGR projects. This document includeds the basic philosophy, performing V and V effort, software testing techniques, criteria of review and audit on the safety software V and V activity. Major review topics on safety software addresses three kinds of characteristics based on Standard Review Plan(SRP) Chapter 7, Branch Technical Position(BTP)-14 : management characteristics, implementation characteristics and resources characteristics when reviewing on SVVP. Based on major topics of this document, we have produced the evaluation items list such as checklist in Appendix A

  2. Integrating respiratory-gated PET-based target volume delineation in liver SBRT planning, a pilot study

    International Nuclear Information System (INIS)

    Riou, Olivier; Thariat, Juliette; Serrano, Benjamin; Azria, David; Paulmier, Benoit; Villeneuve, Remy; Fenoglietto, Pascal; Artenie, Antonella; Ortholan, Cécile; Faraggi, Marc

    2014-01-01

    To assess the feasibility and benefit of integrating four-dimensional (4D) Positron Emission Tomography (PET) – computed tomography (CT) for liver stereotactic body radiation therapy (SBRT) planning. 8 patients with 14 metastases were accrued in the study. They all underwent a non-gated PET and a 4D PET centered on the liver. The same CT scan was used for attenuation correction, registration, and considered the planning CT for SBRT planning. Six PET phases were reconstructed for each 4D PET. By applying an individualized threshold to the 4D PET, a Biological Internal Target Volume (BITV) was generated for each lesion. A gated Planning Target Volume (PTVg) was created by adding 3 mm to account for set-up margins. This volume was compared to a manual Planning Target Volume (PTV) delineated with the help of a semi-automatic Biological Target Volume (BTV) obtained from the non-gated exam. A 5 mm radial and a 10 mm craniocaudal margins were applied to account for tumor motion and set-up margins to create the PTV. One undiagnosed liver metastasis was discovered thanks to the 4D PET. The semi-automatic BTV were significantly smaller than the BITV (p = 0.0031). However, after applying adapted margins, 4D PET allowed a statistically significant decrease in the PTVg as compared to the PTV (p = 0.0052). In comparison to non-gated PET, 4D PET may better define the respiratory movements of liver targets and improve SBRT planning for liver metastases. Furthermore, non respiratory-gated PET exams can both misdiagnose liver metastases and underestimate the real internal target volumes

  3. 18F-fluorodeoxyglucose PET in definition of target volumes and radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Qiao Wenli; Zhao Jinhua

    2007-01-01

    PET is a functional imaging modality, which can give some biological information of tumor. PET is more and more important in the definition of target volumes and radiotherapy treatment planning. Depending on its sensitivity and specificity, 18 F-fluorideoxyglucose 18 F-FDG PET has been shown to influence the selection of target volumes and radiotherapy treatment planning for non-small cell lung cancers, for head and neck squamous cell carcinomas or for esophageal tumors. On the other hand, for tumors such as rectal carcinomas, convincing data on the value of 18 F-FDG PET for target volume selection are still lacking. However, the application of 18 F-FDG PET in many aspects of radiotherapy is still controversy. Further researches in its clinical application are still needed to investigate whether 18 F-FDG PET for treatment planning should be routine because of the lack of prospective studies. (authors)

  4. Knowledge-based radiation therapy (KBRT) treatment planning versus planning by experts: validation of a KBRT algorithm for prostate cancer treatment planning

    International Nuclear Information System (INIS)

    Nwankwo, Obioma; Mekdash, Hana; Sihono, Dwi Seno Kuncoro; Wenz, Frederik; Glatting, Gerhard

    2015-01-01

    A knowledge-based radiation therapy (KBRT) treatment planning algorithm was recently developed. The purpose of this work is to investigate how plans that are generated with the objective KBRT approach compare to those that rely on the judgment of the experienced planner. Thirty volumetric modulated arc therapy plans were randomly selected from a database of prostate plans that were generated by experienced planners (expert plans). The anatomical data (CT scan and delineation of organs) of these patients and the KBRT algorithm were given to a novice with no prior treatment planning experience. The inexperienced planner used the knowledge-based algorithm to predict the dose that the OARs receive based on their proximity to the treated volume. The population-based OAR constraints were changed to the predicted doses. A KBRT plan was subsequently generated. The KBRT and expert plans were compared for the achieved target coverage and OAR sparing. The target coverages were compared using the Uniformity Index (UI), while 5 dose-volume points (D 10 , D 30, D 50 , D 70 and D 90 ) were used to compare the OARs (bladder and rectum) doses. Wilcoxon matched-pairs signed rank test was used to check for significant differences (p < 0.05) between both datasets. The KBRT and expert plans achieved mean UI values of 1.10 ± 0.03 and 1.10 ± 0.04, respectively. The Wilcoxon test showed no statistically significant difference between both results. The D 90 , D 70, D 50 , D 30 and D 10 values of the two planning strategies, and the Wilcoxon test results suggests that the KBRT plans achieved a statistically significant lower bladder dose (at D 30 ), while the expert plans achieved a statistically significant lower rectal dose (at D 10 and D 30 ). The results of this study show that the KBRT treatment planning approach is a promising method to objectively incorporate patient anatomical variations in radiotherapy treatment planning

  5. The relationship between the bladder volume and optimal treatment planning in definitive radiotherapy for localized prostate cancer

    International Nuclear Information System (INIS)

    Nakamura, Naoki; Sekiguchi, Kenji; Akahane, Keiko; Shikama, Naoto; Takahashi, Osamu; Hama, Yukihiro; Nakagawa, Keiichi

    2012-01-01

    Background and purpose: There is no current consensus regarding the optimal bladder volumes in definitive radiotherapy for localized prostate cancer. The aim of this study was to clarify the relationship between the bladder volume and optimal treatment planning in radiotherapy for localized prostate cancer. Material and methods: Two hundred and forty-three patients underwent definitive radiotherapy with helical tomotherapy for intermediate- and high-risk localized prostate cancer. The prescribed dose defined as 95 % of the planning target volume (PTV) receiving 100 % of the prescription dose was 76 Gy in 38 fractions. The clinical target volume (CTV) was defined as the prostate with a 5-mm margin and 2 cm of the proximal seminal vesicle. The PTV was defined as the CTV with a 5-mm margin. Treatment plans were optimized to satisfy the dose constraints defined by in-house protocols for PTV and organs at risk (rectum wall, bladder wall, sigmoid colon and small intestine). If all dose constraints were satisfied, the plan was defined as an optimal plan (OP). Results: An OP was achieved with 203 patients (84%). Mean bladder volume (± 1 SD) was 266 ml (± 130 ml) among those with an OP and 214 ml (±130 ml) among those without an OP (p = 0.02). Logistic regression analysis also showed that bladder volumes below 150 ml decreased the possibility of achieving an OP. However, the percentage of patients with an OP showed a plateau effect at bladder volumes above 150 ml. Conclusions. Bladder volume is a significant factor affecting OP rates. However, our results suggest that bladder volumes exceeding 150 ml may not help meet planning dose constraints

  6. Kilowatt isotope power system. Phase II plan. Volume I. Phase II program plan

    International Nuclear Information System (INIS)

    1978-01-01

    The development of a Kilowatt Isotope Power System (KIPS) was begun in 1975 for the purpose of satisfying the power requirements of satellites in the 1980's. The KIPS is a 238 PuO 2 -fueled organic Rankine cycle turbine power system to provide a design output of 500 to 2000 W. Phase II of the overall 3-phase KIPS program is described. This volume presents a program plan for qualifying the organic Rankine power system for flight test in 1982. The program plan calls for the design and fabrication of the proposed flight power system; conducting a development and a qualification program including both environmental and endurance testing, using an electrical and a radioisotope heat source; planning for flight test and spacecraft integration; and continuing ground demonstration system testing to act as a flight system breadboard and to accumulate life data

  7. Open source deformable image registration system for treatment planning and recurrence CT scans. Validation in the head and neck region

    International Nuclear Information System (INIS)

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Roenn; Bertelsen, Anders; Johansen, Joergen; Eriksen, Jesper Grau; Grau, Cai

    2016-01-01

    Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p < 0.001) and tissue rigidity (r = 0.54, p < 0.001). DIR using elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images. (orig.) [de

  8. Open source deformable image registration system for treatment planning and recurrence CT scans : Validation in the head and neck region.

    Science.gov (United States)

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn; Bertelsen, Anders; Johansen, Jørgen; Grau, Cai; Eriksen, Jesper Grau

    2016-08-01

    Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images.

  9. Broadband Fan Noise Prediction System for Turbofan Engines. Volume 3; Validation and Test Cases

    Science.gov (United States)

    Morin, Bruce L.

    2010-01-01

    Pratt & Whitney has developed a Broadband Fan Noise Prediction System (BFaNS) for turbofan engines. This system computes the noise generated by turbulence impinging on the leading edges of the fan and fan exit guide vane, and noise generated by boundary-layer turbulence passing over the fan trailing edge. BFaNS has been validated on three fan rigs that were tested during the NASA Advanced Subsonic Technology Program (AST). The predicted noise spectra agreed well with measured data. The predicted effects of fan speed, vane count, and vane sweep also agreed well with measurements. The noise prediction system consists of two computer programs: Setup_BFaNS and BFaNS. Setup_BFaNS converts user-specified geometry and flow-field information into a BFaNS input file. From this input file, BFaNS computes the inlet and aft broadband sound power spectra generated by the fan and FEGV. The output file from BFaNS contains the inlet, aft and total sound power spectra from each noise source. This report is the third volume of a three-volume set documenting the Broadband Fan Noise Prediction System: Volume 1: Setup_BFaNS User s Manual and Developer s Guide; Volume 2: BFaNS User s Manual and Developer s Guide; and Volume 3: Validation and Test Cases. The present volume begins with an overview of the Broadband Fan Noise Prediction System, followed by validation studies that were done on three fan rigs. It concludes with recommended improvements and additional studies for BFaNS.

  10. VERA-CS Verification & Validation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States)

    2017-02-01

    This report summarizes the current status of VERA-CS Verification and Validation for PWR Core Follow operation and proposes a multi-phase plan for continuing VERA-CS V&V in FY17 and FY18. The proposed plan recognizes the hierarchical nature of a multi-physics code system such as VERA-CS and the importance of first achieving an acceptable level of V&V on each of the single physics codes before focusing on the V&V of the coupled physics solution. The report summarizes the V&V of each of the single physics codes systems currently used for core follow analysis (ie MPACT, CTF, Multigroup Cross Section Generation, and BISON / Fuel Temperature Tables) and proposes specific actions to achieve a uniformly acceptable level of V&V in FY17. The report also recognizes the ongoing development of other codes important for PWR Core Follow (e.g. TIAMAT, MAMBA3D) and proposes Phase II (FY18) VERA-CS V&V activities in which those codes will also reach an acceptable level of V&V. The report then summarizes the current status of VERA-CS multi-physics V&V for PWR Core Follow and the ongoing PWR Core Follow V&V activities for FY17. An automated procedure and output data format is proposed for standardizing the output for core follow calculations and automatically generating tables and figures for the VERA-CS Latex file. A set of acceptance metrics is also proposed for the evaluation and assessment of core follow results that would be used within the script to automatically flag any results which require further analysis or more detailed explanation prior to being added to the VERA-CS validation base. After the Automation Scripts have been completed and tested using BEAVRS, the VERA-CS plan proposes the Watts Bar cycle depletion cases should be performed with the new cross section library and be included in the first draft of the new VERA-CS manual for release at the end of PoR15. Also, within the constraints imposed by the proprietary nature of plant data, as many as possible of the FY17

  11. NRC action plan developed as a result of the TMI-2 accident. Volume 2

    International Nuclear Information System (INIS)

    1980-05-01

    The Action Plan provides a comprehensive and integrated plan for all actions judged necessary by the Nuclear Regulatory Commission to correct or improve the regulation and operation of nuclear facilities based on the experience from the accident at the Three Mile Island, Unit 2, nuclear facility and the official studies and investigations of the accident. The tables included in this volume list the recommendations from the various organizations and task forces investigating the accident at Three Mile Island. The tables are annotated to provide easy references to the associated parts of the Action Plan in Volume 1. The tables are also annotated to provide a shorthand indication of how the various recommendations are treated in the Action Plan

  12. SU-F-T-378: Evaluation of Dose-Volume Variability and Parameters Between Prostate IMRT and VMAT Plans

    Energy Technology Data Exchange (ETDEWEB)

    Chow, J [Princess Margaret Cancer Centre, Toronto, ON (Canada); Jiang, R [Grand River Regional Cancer Centre, Kitchener, ON (Canada); Kiciak, A [University of Waterloo, Waterloo, ON (Canada)

    2016-06-15

    Purpose: This study compared the rectal dose-volume consistency, equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) in prostate intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT). Methods: For forty prostate IMRT and fifty VMAT patients treated using the same dose prescription (78 Gy/39 fraction) and dose-volume criteria in inverse planning optimization, the rectal EUD and NTCP were calculated for each patient. The rectal dose-volume consistency, showing the variability of dose-volume histogram (DVH) among patients, was defined and calculated based on the deviation between the mean and corresponding rectal DVH. Results: From both the prostate IMRT and VMAT plans, the rectal EUD and NTCP were found decreasing with the rectal volume. The decrease rates for the IMRT plans (EUD = 0.47 × 10{sup −3} Gy cm{sup −3} and NTCP = 3.94 × 10{sup −2} % cm{sup −3}) were higher than those for the VMAT (EUD = 0.28 × 10{sup −3} Gy cm{sup −3} and NTCP = 2.61 × 10{sup −2} % cm{sup −3}). In addition, the dependences of the rectal EUD and NTCP on the dose-volume consistency were found very similar between the prostate IMRT and VMAT plans. This shows that both delivery techniques have similar variations of the rectal EUD and NTCP on the dose-volume consistency. Conclusion: Dependences of the dose-volume consistency on the rectal EUD and NTCP were compared between the prostate IMRT and VMAT plans. It is concluded that both rectal EUD and NTCP decreased with an increase of the rectal volume. The variation rates of the rectal EUD and NTCP on the rectal volume were higher for the IMRT plans than VMAT. However, variations of the rectal dose-volume consistency on the rectal EUD and NTCP were found not significant for both delivery techniques.

  13. The spill prevention, control, and countermeasures (SPCC) plan for the Y-12 Plant. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    This spill prevention, control and countermeasures (SPCC) Plan is divided into two volumes. Volume I addresses Y-12`s compliance with regulations pertinent to the content of SPCC Plans. Volume II is the SPCC Hazardous Material Storage Data Base, a detailed tabulation of facility-specific information and data on potential spill sources at the Y-12 Plant. Volume I follows the basic format and subject sequence specified in 40 CFR 112.7. This sequence is prefaced by three additional chapters, including this introduction and brief discussions of the Y-12 Plant`s background/environmental setting and potential spill source categories. Two additional chapters on containers and container storage areas and PCB and PCB storage for disposal facilities are inserted into the required sequence. The following required subjects are covered in this volume: Spill history, site drainage; secondary containment/diversion structures and equipment; contingency plans; notification and spill response procedures; facility drainage; bulk storage tanks; facility transfer operations, pumping, and in-plant processes; transfer stations (facility tank cars/tank tracks); inspections and records; security, and personnel, training, and spill prevention procedures.

  14. Space Assembly, Maintenance and Servicing Study. Volume 4: Concept Development Plan

    National Research Council Canada - National Science Library

    1986-01-01

    .... This concept development program (CDP), Volume IV of the SAMS final report, contains a summary of the selection of CDP candidates and a plan for completing the required analysis, tests and demonstrations...

  15. Proposed Site Treatment Plan (PSTP). Volumes 1 and 2 and Reference Document

    Energy Technology Data Exchange (ETDEWEB)

    Helmich, E.; Noller, D.K.; Wierzbicki, K.S.; Bailey, L.L.

    1994-12-22

    The Compliance Plan Volume provides overall schedules with target dates for achieving compliance with the land disposal restrictions (LDR) and contains procedures to establish milestones to be enforced under the Order. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume and is provided for informational purposes only.

  16. Prototyping and validating requirements of radiation and nuclear emergency plan simulator

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, AHA., E-mail: amyhamijah@nm.gov.my [Malaysian Nuclear Agency (NM), Bangi, 43000 Kajang, Selangor (Malaysia); Faculty of Computing, Universiti Teknologi Malaysia (UTM), Skudai, 81310 Johor Bahru, Johor (Malaysia); Rozan, MZA.; Ibrahim, R.; Deris, S.; Selamat, A. [Faculty of Computing, Universiti Teknologi Malaysia (UTM), Skudai, 81310 Johor Bahru, Johor (Malaysia)

    2015-04-29

    Organizational incapability in developing unrealistic, impractical, inadequate and ambiguous mechanisms of radiological and nuclear emergency preparedness and response plan (EPR) causing emergency plan disorder and severe disasters. These situations resulting from 65.6% of poor definition and unidentified roles and duties of the disaster coordinator. Those unexpected conditions brought huge aftermath to the first responders, operators, workers, patients and community at large. Hence, in this report, we discuss prototyping and validating of Malaysia radiation and nuclear emergency preparedness and response plan simulation model (EPRM). A prototyping technique was required to formalize the simulation model requirements. Prototyping as systems requirements validation was carried on to endorse the correctness of the model itself against the stakeholder’s intensions in resolving those organizational incapability. We have made assumptions for the proposed emergency preparedness and response model (EPRM) through the simulation software. Those assumptions provided a twofold of expected mechanisms, planning and handling of the respective emergency plan as well as in bringing off the hazard involved. This model called RANEPF (Radiation and Nuclear Emergency Planning Framework) simulator demonstrated the training emergency response perquisites rather than the intervention principles alone. The demonstrations involved the determination of the casualties’ absorbed dose range screening and the coordination of the capacity planning of the expected trauma triage. Through user-centred design and sociotechnical approach, RANEPF simulator was strategized and simplified, though certainly it is equally complex.

  17. Prototyping and validating requirements of radiation and nuclear emergency plan simulator

    Science.gov (United States)

    Hamid, AHA.; Rozan, MZA.; Ibrahim, R.; Deris, S.; Selamat, A.

    2015-04-01

    Organizational incapability in developing unrealistic, impractical, inadequate and ambiguous mechanisms of radiological and nuclear emergency preparedness and response plan (EPR) causing emergency plan disorder and severe disasters. These situations resulting from 65.6% of poor definition and unidentified roles and duties of the disaster coordinator. Those unexpected conditions brought huge aftermath to the first responders, operators, workers, patients and community at large. Hence, in this report, we discuss prototyping and validating of Malaysia radiation and nuclear emergency preparedness and response plan simulation model (EPRM). A prototyping technique was required to formalize the simulation model requirements. Prototyping as systems requirements validation was carried on to endorse the correctness of the model itself against the stakeholder's intensions in resolving those organizational incapability. We have made assumptions for the proposed emergency preparedness and response model (EPRM) through the simulation software. Those assumptions provided a twofold of expected mechanisms, planning and handling of the respective emergency plan as well as in bringing off the hazard involved. This model called RANEPF (Radiation and Nuclear Emergency Planning Framework) simulator demonstrated the training emergency response perquisites rather than the intervention principles alone. The demonstrations involved the determination of the casualties' absorbed dose range screening and the coordination of the capacity planning of the expected trauma triage. Through user-centred design and sociotechnical approach, RANEPF simulator was strategized and simplified, though certainly it is equally complex.

  18. Prototyping and validating requirements of radiation and nuclear emergency plan simulator

    International Nuclear Information System (INIS)

    Hamid, AHA.; Rozan, MZA.; Ibrahim, R.; Deris, S.; Selamat, A.

    2015-01-01

    Organizational incapability in developing unrealistic, impractical, inadequate and ambiguous mechanisms of radiological and nuclear emergency preparedness and response plan (EPR) causing emergency plan disorder and severe disasters. These situations resulting from 65.6% of poor definition and unidentified roles and duties of the disaster coordinator. Those unexpected conditions brought huge aftermath to the first responders, operators, workers, patients and community at large. Hence, in this report, we discuss prototyping and validating of Malaysia radiation and nuclear emergency preparedness and response plan simulation model (EPRM). A prototyping technique was required to formalize the simulation model requirements. Prototyping as systems requirements validation was carried on to endorse the correctness of the model itself against the stakeholder’s intensions in resolving those organizational incapability. We have made assumptions for the proposed emergency preparedness and response model (EPRM) through the simulation software. Those assumptions provided a twofold of expected mechanisms, planning and handling of the respective emergency plan as well as in bringing off the hazard involved. This model called RANEPF (Radiation and Nuclear Emergency Planning Framework) simulator demonstrated the training emergency response perquisites rather than the intervention principles alone. The demonstrations involved the determination of the casualties’ absorbed dose range screening and the coordination of the capacity planning of the expected trauma triage. Through user-centred design and sociotechnical approach, RANEPF simulator was strategized and simplified, though certainly it is equally complex

  19. Guidelines for Sandia ASCI Verification and Validation Plans - Content and Format: Version 1.0

    Energy Technology Data Exchange (ETDEWEB)

    TRUCANO,TIMOTHY G.; MOYA,JAIME L.

    1999-12-01

    This report summarizes general guidelines for the development of Verification and Validation (V and V) plans for ASCI code projects at Sandia National Laboratories. The main content categories recommended by these guidelines for explicit treatment in Sandia V and V plans are (1) stockpile drivers influencing the code development project (2) the key phenomena to be modeled by the individual code; (3) software verification strategy and test plan; and (4) code validation strategy and test plans. The authors of this document anticipate that the needed content of the V and V plans for the Sandia ASCI codes will evolve as time passes. These needs will be reflected by future versions of this document.

  20. Tumor and normal structures volume localization and quantitation in 3D radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Anselmi, R.; Andreucci, L.

    1995-01-01

    Improvements in imaging technology have significantly enhanced the ability of the radiation oncologist to stage and to evaluate the response of tumor during and after treatment. Over the last few year, in fact, computed tomography (CT), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), single photon emission computed tomography (SPECT) imaging radiolabelled monoclonal tumor antibodies have allowed tumor definition and evaluation. Concerning the above mentioned techniques accurate methods for the integration of morphological (CT, MRI) and functional (PET, SPECT, MRS) information can be very useful for volumes definition. In fact three-dimensional treatment planning depends heavily on volume displays and calculation based on volumes to convey information to the radiation oncologist, physicist and dosimetrist. The accuracy and reproducibility of the methods for creating these volumes are fundamental limitations of current treatment planning systems. Slice by slice manual contouring, which is extremely labor-intensive, and automatic edge detection, which has a high failure rate and requires human intervention are representative of the current standard of practice. The aim of our work is both to develop methods of image data integration and automatic segmentation, and to make the treatment planning system able to combine these multiple information in unified data set in order to get a better tumor volume definition and dose distribution calculation. Then the possibility of using morphological and functional images and other information coming from MR spectroscopy and electronic or confocal microscopy can allow the development into the treatment planning system of biological calculation models for evaluating tumor and normal tissue control probabilities (TCP, NTCP). The definitive use of these models into the 3-D treatment plannings will offer a considerable improvement in the biological efficacy of radiotherapy and it will constitute the object

  1. Leak testing plan for the Oak Ridge National Laboratory liquid low-level waste systems (active tanks): Revision 2. Volume 1: Regulatory background and plan approach; Volume 2: Methods, protocols, and schedules; Volume 3: Evaluation of the ORNL/LT-823DP differential pressure leak detection method; Appendix to Revision 2: DOE/EPA/TDEC correspondence

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, D.G.; Wise, R.F.; Starr, J.W.; Maresca, J.W. Jr. [Vista Research, Inc., Mountain View, CA (United States)

    1994-11-01

    This document, the Leak Testing Plan for the Oak Ridge National Laboratory Liquid Low-Level Waste System (Active Tanks), comprises three volumes. The first two volumes address the component-based leak testing plan for the liquid low-level waste system at Oak Ridge, while the third volume describes the performance evaluation of the leak detection method that will be used to test this system. Volume 1, describes that portion of the liquid low-level waste system at that will be tested; it provides the regulatory background, especially in terms of the requirements stipulated in the Federal Facilities Agreement, upon which the leak testing plan is based. Volume 1 also describes the foundation of the plan, portions of which were abstracted from existing federal documents that regulate the petroleum and hazardous chemicals industries. Finally, Volume 1 gives an overview the plan, describing the methods that will be used to test the four classes of components in the liquid low-level waste system. Volume 2 takes the general information on component classes and leak detection methods presented in Volume 1 and shows how it applies particularly to each of the individual components. A complete test plan for each of the components is presented, with emphasis placed on the methods designated for testing tanks. The protocol for testing tank systems is described, and general leak testing schedules are presented. Volume 3 describes the results of a performance evaluation completed for the leak testing method that will be used to test the small tanks at the facility (those less than 3,000 gal in capacity). Some of the details described in Volumes 1 and 2 are expected to change as additional information is obtained, as the viability of candidate release detection methods is proven in the Oak Ridge environment, and as the testing program evolves.

  2. Leak testing plan for the Oak Ridge National Laboratory liquid low-level waste systems (active tanks): Revision 2. Volume 1: Regulatory background and plan approach; Volume 2: Methods, protocols, and schedules; Volume 3: Evaluation of the ORNL/LT-823DP differential pressure leak detection method; Appendix to Revision 2: DOE/EPA/TDEC correspondence

    International Nuclear Information System (INIS)

    Douglas, D.G.; Wise, R.F.; Starr, J.W.; Maresca, J.W. Jr.

    1994-11-01

    This document, the Leak Testing Plan for the Oak Ridge National Laboratory Liquid Low-Level Waste System (Active Tanks), comprises three volumes. The first two volumes address the component-based leak testing plan for the liquid low-level waste system at Oak Ridge, while the third volume describes the performance evaluation of the leak detection method that will be used to test this system. Volume 1, describes that portion of the liquid low-level waste system at that will be tested; it provides the regulatory background, especially in terms of the requirements stipulated in the Federal Facilities Agreement, upon which the leak testing plan is based. Volume 1 also describes the foundation of the plan, portions of which were abstracted from existing federal documents that regulate the petroleum and hazardous chemicals industries. Finally, Volume 1 gives an overview the plan, describing the methods that will be used to test the four classes of components in the liquid low-level waste system. Volume 2 takes the general information on component classes and leak detection methods presented in Volume 1 and shows how it applies particularly to each of the individual components. A complete test plan for each of the components is presented, with emphasis placed on the methods designated for testing tanks. The protocol for testing tank systems is described, and general leak testing schedules are presented. Volume 3 describes the results of a performance evaluation completed for the leak testing method that will be used to test the small tanks at the facility (those less than 3,000 gal in capacity). Some of the details described in Volumes 1 and 2 are expected to change as additional information is obtained, as the viability of candidate release detection methods is proven in the Oak Ridge environment, and as the testing program evolves

  3. Management plan documentation standard and Data Item Descriptions (DID). Volume of the information system life-cycle and documentation standards, volume 2

    Science.gov (United States)

    Callender, E. David; Steinbacher, Jody

    1989-01-01

    This is the second of five volumes of the Information System Life-Cycle and Documentation Standards. This volume provides a well-organized, easily used standard for management plans used in acquiring, assuring, and developing information systems and software, hardware, and operational procedures components, and related processes.

  4. Guidance and Control Software Project Data - Volume 1: Planning Documents

    Science.gov (United States)

    Hayhurst, Kelly J. (Editor)

    2008-01-01

    The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the planning documents from the GCS project. Volume 1 contains five appendices: A. Plan for Software Aspects of Certification for the Guidance and Control Software Project; B. Software Development Standards for the Guidance and Control Software Project; C. Software Verification Plan for the Guidance and Control Software Project; D. Software Configuration Management Plan for the Guidance and Control Software Project; and E. Software Quality Assurance Activities.

  5. Dose-volume histograms for optimization of treatment plans illustrated by the example of oesophagus carcinoma

    International Nuclear Information System (INIS)

    Roth, J.; Huenig, R.; Huegli, C.

    1995-01-01

    Using the example of oesophagus carcinoma, dose-volume histograms for diverse treatment techniques are calculated and judged by means of multiplanar isodose representations. The selected treatment plans are ranked with the aid of the dose-volume histograms. We distinguish the tissue inside and outside of the target volume. The description of the spatial dose distribution in dependence of the different volumes and the respective fractions of the tumor dose therein with the help of dose-volume histograms brings about a correlation between the physical parameters and the biological effects. In addition one has to bear in mind the consequences of measures that influence the reaction and the side-effects of radiotherapy (e.g. chemotherapy), i.e. the recuperation of the tissues that were irradiated intentionally or inevitably. Taking all that into account it is evident that the dose-volume histograms are a powerful tool for assessing the quality of treatment plans. (orig./MG) [de

  6. Guidelines for the verification and validation of expert system software and conventional software: Bibliography. Volume 8

    International Nuclear Information System (INIS)

    Miller, L.A.; Hayes, J.E.; Mirsky, S.M.

    1995-03-01

    This volume contains all of the technical references found in Volumes 1-7 concerning the development of guidelines for the verification and validation of expert systems, knowledge-based systems, other AI systems, object-oriented systems, and conventional systems

  7. Guidelines for the verification and validation of expert system software and conventional software: Bibliography. Volume 8

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L.A.; Hayes, J.E.; Mirsky, S.M. [Science Applications International Corp., McLean, VA (United States)

    1995-03-01

    This volume contains all of the technical references found in Volumes 1-7 concerning the development of guidelines for the verification and validation of expert systems, knowledge-based systems, other AI systems, object-oriented systems, and conventional systems.

  8. Tank waste source term inventory validation. Volume II. Letter report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This document comprises Volume II of the Letter Report entitled Tank Waste Source Term Inventory Validation. This volume contains Appendix C, Radionuclide Tables, and Appendix D, Chemical Analyte Tables. The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories.

  9. Tank waste source term inventory validation. Volume II. Letter report

    International Nuclear Information System (INIS)

    1995-04-01

    This document comprises Volume II of the Letter Report entitled Tank Waste Source Term Inventory Validation. This volume contains Appendix C, Radionuclide Tables, and Appendix D, Chemical Analyte Tables. The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories

  10. Draft Strategic Laboratory Missions Plan. Volume II

    International Nuclear Information System (INIS)

    1996-03-01

    This volume described in detail the Department's research and technology development activities and their funding at the Department's laboratories. It includes 166 Mission Activity Profiles, organized by major mission area, with each representing a discrete budget function called a Budget and Reporting (B ampersand R) Code. The activities profiled here encompass the total research and technology development funding of the laboratories from the Department. Each profile includes a description of the activity and shows how the funding for that activity is distributed among the DOE laboratories as well as universities and industry. The profiles also indicate the principal laboratories for each activity, as well as which other laboratories are involved. The information in this volume is at the core of the Strategic Laboratory Mission Plan. It enables a reader to follow funds from the Department's appropriation to a specific activity description and to specific R ampersand D performing institutions. This information will enable the Department, along with the Laboratory Operations Board and Congress, to review the distribution of R ampersand D performers chosen to execute the Department's missions

  11. Draft Strategic Laboratory Missions Plan. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This volume described in detail the Department`s research and technology development activities and their funding at the Department`s laboratories. It includes 166 Mission Activity Profiles, organized by major mission area, with each representing a discrete budget function called a Budget and Reporting (B & R) Code. The activities profiled here encompass the total research and technology development funding of the laboratories from the Department. Each profile includes a description of the activity and shows how the funding for that activity is distributed among the DOE laboratories as well as universities and industry. The profiles also indicate the principal laboratories for each activity, as well as which other laboratories are involved. The information in this volume is at the core of the Strategic Laboratory Mission Plan. It enables a reader to follow funds from the Department`s appropriation to a specific activity description and to specific R & D performing institutions. This information will enable the Department, along with the Laboratory Operations Board and Congress, to review the distribution of R & D performers chosen to execute the Department`s missions.

  12. SU-C-BRB-03: Cross-Institutional Validation of An Ultrafast Automatic Planning Platform for Breast Irradiation

    International Nuclear Information System (INIS)

    Li, T; Lockamy, V; Anne, P; Simone, N; Yu, Y; Sheng, Y; Wu, QJ

    2016-01-01

    Purpose: Recently an ultrafast automatic planning system for breast irradiation using tangential beams was developed by modeling relationships between patient anatomy and achieved dose distribution. This study evaluates the performance of this system when applied to a different patient population and dose calculation algorithm. Methods: The system and its anatomy-to-dose models was developed at institution A based on 20 cases, which were planned using manual fluence painting technique and calculated WITH heterogeneity correction. Institution B uses field-in-field planning technique and dose calculation WITHOUT heterogeneity correction. 11 breast cases treated at Institution B were randomly selected for retrospective study, including left and right sides, and different breast size (irradiated volumes defined by Jaw/MLC opening range from 875cc to 3516cc). Comparisons between plans generated automatically (Auto-Plans) and those used for treatment (Clinical-Plans) included: energy choice (single/mixed), volumes receiving 95%/100%/105%/110% Rx dose (V95%/V100%/V105%/V100%) relative to irradiated volume, D1cc, and LungV20Gy. Results: In 9 out of 11 cases single/mixed energy choice made by the software agreed with Clinical-Plans. For the remaining 2 cases software recommended using mixed energy and dosimetric improvements were observed. V100% were similar (p=0.223, Wilcoxon Signed-Rank test) between Auto-Plans and Clinical-Plans (57.6±8.9% vs. 54.8±9.5%). V95% is 2.3±3.0% higher for Auto-Plans (p=0.027), indicating reduced cold areas. Hot spot volume V105% were significantly reduced in Auto-Plan by 14.4±7.2% (p=0.004). Absolute V105% was reduced from 395.6±359.9cc for Clinical-Plans to 108.7±163cc for Auto-Plans. D1cc was 107.4±2.8% for Auto-Plans, and 109.2±2.4% for Clinical-Plans (p=0.056). LungV20Gy were 13.6±4.0% for Auto-Plan vs. 14.0±4.1% for Clinical-Plans (p=0.043). All optimizations were finished within 1.5min. Conclusion: The performance of this

  13. SU-C-BRB-03: Cross-Institutional Validation of An Ultrafast Automatic Planning Platform for Breast Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Li, T; Lockamy, V; Anne, P; Simone, N; Yu, Y [Thomas Jefferson University, Philadelphia, PA (United States); Sheng, Y; Wu, QJ [Duke University, Durham, NC (United States)

    2016-06-15

    Purpose: Recently an ultrafast automatic planning system for breast irradiation using tangential beams was developed by modeling relationships between patient anatomy and achieved dose distribution. This study evaluates the performance of this system when applied to a different patient population and dose calculation algorithm. Methods: The system and its anatomy-to-dose models was developed at institution A based on 20 cases, which were planned using manual fluence painting technique and calculated WITH heterogeneity correction. Institution B uses field-in-field planning technique and dose calculation WITHOUT heterogeneity correction. 11 breast cases treated at Institution B were randomly selected for retrospective study, including left and right sides, and different breast size (irradiated volumes defined by Jaw/MLC opening range from 875cc to 3516cc). Comparisons between plans generated automatically (Auto-Plans) and those used for treatment (Clinical-Plans) included: energy choice (single/mixed), volumes receiving 95%/100%/105%/110% Rx dose (V95%/V100%/V105%/V100%) relative to irradiated volume, D1cc, and LungV20Gy. Results: In 9 out of 11 cases single/mixed energy choice made by the software agreed with Clinical-Plans. For the remaining 2 cases software recommended using mixed energy and dosimetric improvements were observed. V100% were similar (p=0.223, Wilcoxon Signed-Rank test) between Auto-Plans and Clinical-Plans (57.6±8.9% vs. 54.8±9.5%). V95% is 2.3±3.0% higher for Auto-Plans (p=0.027), indicating reduced cold areas. Hot spot volume V105% were significantly reduced in Auto-Plan by 14.4±7.2% (p=0.004). Absolute V105% was reduced from 395.6±359.9cc for Clinical-Plans to 108.7±163cc for Auto-Plans. D1cc was 107.4±2.8% for Auto-Plans, and 109.2±2.4% for Clinical-Plans (p=0.056). LungV20Gy were 13.6±4.0% for Auto-Plan vs. 14.0±4.1% for Clinical-Plans (p=0.043). All optimizations were finished within 1.5min. Conclusion: The performance of this

  14. Federal Facility Compliance Act, Proposed Site Treatment Plan: Background Volume. Executive Summary

    International Nuclear Information System (INIS)

    1995-01-01

    This Federal Facility Compliance Act Site Treatment Plan discusses the options of radioactive waste management for Ames Laboratory. This is the background volume which discusses: site history and mission; framework for developing site treatment plans; proposed plan organization and related activities; characterization of mixed waste and waste minimization; low level mixed waste streams and the proposed treatment approach; future generation of TRU and mixed wastes; the adequacy of mixed waste storage facilities; and a summary of the overall DOE activity in the area of disposal of mixed waste treatment residuals

  15. SU-F-T-355: Evaluation of Knowledge-Based Planning Model for the Cervical Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, X; Wang, J; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: The Varian RapidPlan™ is a commercial knowledge-based optimization process which uses a set of clinically used treatment plans to train a model that can predict individualized dose-volume objectives. The purpose of this study is to evaluate the performance of RapidPlan to generate intensity modulated radiation therapy (IMRT) plans for cervical cancer. Methods: Totally 70 IMRT plans for cervical cancer with varying clinical and physiological indications were enrolled in this study. These patients were all previously treated in our institution. There were two prescription levels usually used in our institution: 45Gy/25 fractions and 50.4Gy/28 fractions. 50 of these plans were selected to train the RapidPlan model for predicting dose-volume constraints. After model training, this model was validated with 10 plans from training pool(internal validation) and additional other 20 new plans(external validation). All plans used for the validation were re-optimized with the original beam configuration and the generated priorities from RapidPlan were manually adjusted to ensure that re-optimized DVH located in the range of the model prediction. DVH quantitative analysis was performed to compare the RapidPlan generated and the original manual optimized plans. Results: For all the validation cases, RapidPlan based plans (RapidPlan) showed similar or superior results compared to the manual optimized ones. RapidPlan increased the result of D98% and homogeneity in both two validations. For organs at risk, the RapidPlan decreased mean doses of bladder by 1.25Gy/1.13Gy (internal/external validation) on average, with p=0.12/p<0.01. The mean dose of rectum and bowel were also decreased by an average of 2.64Gy/0.83Gy and 0.66Gy/1.05Gy,with p<0.01/ p<0.01and p=0.04/<0.01 for the internal/external validation, respectively. Conclusion: The RapidPlan model based cervical cancer plans shows ability to systematically improve the IMRT plan quality. It suggests that RapidPlan has

  16. SU-F-T-355: Evaluation of Knowledge-Based Planning Model for the Cervical Cancer Radiotherapy

    International Nuclear Information System (INIS)

    Chen, X; Wang, J; Hu, W

    2016-01-01

    Purpose: The Varian RapidPlan™ is a commercial knowledge-based optimization process which uses a set of clinically used treatment plans to train a model that can predict individualized dose-volume objectives. The purpose of this study is to evaluate the performance of RapidPlan to generate intensity modulated radiation therapy (IMRT) plans for cervical cancer. Methods: Totally 70 IMRT plans for cervical cancer with varying clinical and physiological indications were enrolled in this study. These patients were all previously treated in our institution. There were two prescription levels usually used in our institution: 45Gy/25 fractions and 50.4Gy/28 fractions. 50 of these plans were selected to train the RapidPlan model for predicting dose-volume constraints. After model training, this model was validated with 10 plans from training pool(internal validation) and additional other 20 new plans(external validation). All plans used for the validation were re-optimized with the original beam configuration and the generated priorities from RapidPlan were manually adjusted to ensure that re-optimized DVH located in the range of the model prediction. DVH quantitative analysis was performed to compare the RapidPlan generated and the original manual optimized plans. Results: For all the validation cases, RapidPlan based plans (RapidPlan) showed similar or superior results compared to the manual optimized ones. RapidPlan increased the result of D98% and homogeneity in both two validations. For organs at risk, the RapidPlan decreased mean doses of bladder by 1.25Gy/1.13Gy (internal/external validation) on average, with p=0.12/p<0.01. The mean dose of rectum and bowel were also decreased by an average of 2.64Gy/0.83Gy and 0.66Gy/1.05Gy,with p<0.01/ p<0.01and p=0.04/<0.01 for the internal/external validation, respectively. Conclusion: The RapidPlan model based cervical cancer plans shows ability to systematically improve the IMRT plan quality. It suggests that RapidPlan has

  17. IMRT: Improvement in treatment planning efficiency using NTCP calculation independent of the dose-volume-histogram

    International Nuclear Information System (INIS)

    Grigorov, Grigor N.; Chow, James C.L.; Grigorov, Lenko; Jiang, Runqing; Barnett, Rob B.

    2006-01-01

    The normal tissue complication probability (NTCP) is a predictor of radiobiological effect for organs at risk (OAR). The calculation of the NTCP is based on the dose-volume-histogram (DVH) which is generated by the treatment planning system after calculation of the 3D dose distribution. Including the NTCP in the objective function for intensity modulated radiation therapy (IMRT) plan optimization would make the planning more effective in reducing the postradiation effects. However, doing so would lengthen the total planning time. The purpose of this work is to establish a method for NTCP determination, independent of a DVH calculation, as a quality assurance check and also as a mean of improving the treatment planning efficiency. In the study, the CTs of ten randomly selected prostate patients were used. IMRT optimization was performed with a PINNACLE3 V 6.2b planning system, using planning target volume (PTV) with margins in the range of 2 to 10 mm. The DVH control points of the PTV and OAR were adapted from the prescriptions of Radiation Therapy Oncology Group protocol P-0126 for an escalated prescribed dose of 82 Gy. This paper presents a new model for the determination of the rectal NTCP ( R NTCP). The method uses a special function, named GVN (from Gy, Volume, NTCP), which describes the R NTCP if 1 cm 3 of the volume of intersection of the PTV and rectum (R int ) is irradiated uniformly by a dose of 1 Gy. The function was 'geometrically' normalized using a prostate-prostate ratio (PPR) of the patients' prostates. A correction of the R NTCP for different prescribed doses, ranging from 70 to 82 Gy, was employed in our model. The argument of the normalized function is the R int , and parameters are the prescribed dose, prostate volume, PTV margin, and PPR. The R NTCPs of another group of patients were calculated by the new method and the resulting difference was <±5% in comparison to the NTCP calculated by the PINNACLE3 software where Kutcher's dose

  18. Preliminary Validation and Verification Plan for CAREM Reactor Protection System; Modelo de Plan Preliminar de Validacion y Verificacion para el Sistema de Proteccion del Reactor CAREM

    Energy Technology Data Exchange (ETDEWEB)

    Fittipaldi, Ana; Felix, Maciel [Comision Nacional de Energia Atomica, Centro Atomico Bariloche (Argentina)

    2000-07-01

    The purpose of this paper, is to present a preliminary validation and verification plan for a particular architecture proposed for the CAREM reactor protection system with software modules (computer based system).These software modules can be either own design systems or systems based in commercial modules such as programmable logic controllers (PLC) redundant of last generation.During this study, it was seen that this plan can also be used as a validation and verification plan of commercial products (COTS, commercial off the shelf) and/or smart transmitters.The software life cycle proposed and its features are presented, and also the advantages of the preliminary validation and verification plan.

  19. Comparison of different application systems and CT- assisted treatment planning procedures in primary endometrium cancer: Is it technically possible to include the whole uterus volume in the volume treated by brachytherapy

    International Nuclear Information System (INIS)

    Mock, U.; Knocke, Th.; Fellner, C.; Poetter, R.

    1996-01-01

    Purpose: Brachytherapy is regarded as the definitive component of treatment for inoperable patients with endometrium cancer. In published series the whole uterus has been claimed to represent the target volume independently of the individual tumor spread. The purpose of this work is to compare different planning and application procedures and to analyze the target volumes (whole uterus), treatment volumes and their respective relation for the given various conditions. Material and Methods: In ten patients with primary endometrium cancer the correlation between target- and treatment volume was analysed based on standard one-channel applicators or individual Heyman applicators. A comparative analysis of target volumes resulting from two different planning procedures of Heyman applications was performed. CT was carried out after insertion of the Heyman ovoids. Target volume was estimated by measuring the uterus size at different cross sections of the CT images. Dose calculation was performed with (PLATO-system) or without (NPS-system) transferring these data directly to the planning system. We report on the differences in treatment volumes resulting from the two application and planning systems. Results: The mean value of the uterus volume was 180 ccm (range 57 ccm to 316 ccm). Four out of 10 patients had an asymmetric uterus configuration with a side-difference (in longitudinal or transversal direction) of more than 1 cm. On average 70% (range 48-95%) of the uterus volume was included by the treatment volume when Heymann applicators were used compared to 45 % (range 25-89%) when standard one channel applicators were used. This represents an improvement of 25% (range from 11%-35%). By utilizing the more sophisticated way of treatment planning a more adequate coverage of the uterus volume was achieved in five out of ten patients. The treated volume increased on the average by 20 % (range 11 %-32%). In three cases changes in the irradiation volume were less than 5%. In

  20. Inverse optimization of objective function weights for treatment planning using clinical dose-volume histograms

    Science.gov (United States)

    Babier, Aaron; Boutilier, Justin J.; Sharpe, Michael B.; McNiven, Andrea L.; Chan, Timothy C. Y.

    2018-05-01

    We developed and evaluated a novel inverse optimization (IO) model to estimate objective function weights from clinical dose-volume histograms (DVHs). These weights were used to solve a treatment planning problem to generate ‘inverse plans’ that had similar DVHs to the original clinical DVHs. Our methodology was applied to 217 clinical head and neck cancer treatment plans that were previously delivered at Princess Margaret Cancer Centre in Canada. Inverse plan DVHs were compared to the clinical DVHs using objective function values, dose-volume differences, and frequency of clinical planning criteria satisfaction. Median differences between the clinical and inverse DVHs were within 1.1 Gy. For most structures, the difference in clinical planning criteria satisfaction between the clinical and inverse plans was at most 1.4%. For structures where the two plans differed by more than 1.4% in planning criteria satisfaction, the difference in average criterion violation was less than 0.5 Gy. Overall, the inverse plans were very similar to the clinical plans. Compared with a previous inverse optimization method from the literature, our new inverse plans typically satisfied the same or more clinical criteria, and had consistently lower fluence heterogeneity. Overall, this paper demonstrates that DVHs, which are essentially summary statistics, provide sufficient information to estimate objective function weights that result in high quality treatment plans. However, as with any summary statistic that compresses three-dimensional dose information, care must be taken to avoid generating plans with undesirable features such as hotspots; our computational results suggest that such undesirable spatial features were uncommon. Our IO-based approach can be integrated into the current clinical planning paradigm to better initialize the planning process and improve planning efficiency. It could also be embedded in a knowledge-based planning or adaptive radiation therapy framework to

  1. RELAP-7 Software Verification and Validation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk, Reliability, and Regulatory Support; Choi, Yong-Joon [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk, Reliability, and Regulatory Support; Zou, Ling [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk, Reliability, and Regulatory Support

    2014-09-25

    This INL plan comprehensively describes the software for RELAP-7 and documents the software, interface, and software design requirements for the application. The plan also describes the testing-based software verification and validation (SV&V) process—a set of specially designed software models used to test RELAP-7. The RELAP-7 (Reactor Excursion and Leak Analysis Program) code is a nuclear reactor system safety analysis code being developed at Idaho National Laboratory (INL). The code is based on the INL’s modern scientific software development framework – MOOSE (Multi-Physics Object-Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5’s capability and extends the analysis capability for all reactor system simulation scenarios.

  2. Recommended criteria for the evaluation of on-site nuclear power plant emergency plans, volume II: criteria

    International Nuclear Information System (INIS)

    1997-01-01

    A critical review of existing Canadian and international nuclear power plant (NPP) emergency plans, evaluation criteria, and approaches has been conducted to provide AECB staff with information which can be used to assess the adequacy of NPP on-site emergency response plans. The results of this work are published in two volumes. Volume I, Basis Document, provides the reasons why certain requirements are in place. It also gives comprehensive references to various standards.Volume II, Criteria, contains the criteria which relate to on-site actions and their integration with control room activities and the roles of off-site responsible organizations. The recommended criteria provide information on what is required, and not on how to accomplish the requirements. The licensees are given the latitude to decide on the methods and processes needed to meet the requirements. The documents do not address NPP off-site plans and response capability, or the control room emergency operating procedures and response capability. This report contains only Volume II: Criteria. 55 refs., 2 tabs., 1 fig

  3. Does the IMRT technique allow improvement of treatment plans (e.g. lung sparing) for lung cancer patients with small lung volume: a planning study

    International Nuclear Information System (INIS)

    Komosinska, K.; Kepka, L.; Gizynska, M.; Zawadzka, A.

    2008-01-01

    Aim: We evaluated whether intensity-modulated radiation therapy (IMRT) may offer any advantages in comparison with three-dimensional conformal radiotherapy (3D-CRT) for patients with small lung volume (SLV). Methods: Treatment planning was performed for 10 NSCLC patients with the smallest lung volume (mean: 2241 cc) among 200 patients from our database. For each patient 3D-CRT and IMRT plans were prepared. The goal was to deliver 66 Gy/33 fractions, with dose constraints: mean lung dose (MLD) < 20 Gy, V20 < 35%; spinal cord - Dmax < 45 Gy. When the plan could not meet these criteria, total dose was reduced. The 3D-CRT and IMRT plans were compared. We investigated: prescribed dose, coverage and conformity indices, MLD, V5-V65 in the lung. Results: In 4 out of 10 plans, 3D-CRT did not allow 66 Gy to be delivered, because of predicted pulmonary toxicity. These 4 cases included 3 for which we did not reach 66 Gy with IMRT; still, for these 3 plans the total dose was increased by an average of 9 Gy with IMRT in comparison with 3D-CRT. Coverage indices were similar for both techniques. Conformity indices were better for IMRT plans. MLD was lower in five IMRT and two 3D-CRT plans if equal doses were delivered. The decrease in MLD was seen for cases with large PTV and high PTV/lung volume ratio. Lung V5 was lower for all 3D-CRT plans, 47% vs. 57% for IMRT; V15 and above were larger for 3D-CRT Conclusion: In the planning study, IMRT seems to be a promising technique for cases with SLV, especially when associated with large PT V. (authors)

  4. Design verification and validation plan for the cold vacuum drying facility

    International Nuclear Information System (INIS)

    NISHIKAWA, L.D.

    1999-01-01

    The Cold Vacuum Drying Facility (CVDF) provides the required process systems, supporting equipment, and facilities needed for drying spent nuclear fuel removed from the K Basins. This document presents the both completed and planned design verification and validation activities

  5. Target volume delineation and treatment planning for particle therapy a practical guide

    CERN Document Server

    Leeman, Jonathan E; Cahlon, Oren; Sine, Kevin; Jiang, Guoliang; Lu, Jiade J; Both, Stefan

    2018-01-01

    This handbook is designed to enable radiation oncologists to treat patients appropriately and confidently by means of particle therapy. The orientation and purpose are entirely practical, in that the focus is on the physics essentials of delivery and treatment planning , illustration of the clinical target volume (CTV) and associated treatment planning for each major malignancy when using particle therapy, proton therapy in particular. Disease-specific chapters provide guidelines and concise knowledge on CTV selection and delineation and identify aspects that require the exercise of caution during treatment planning. The treatment planning techniques unique to proton therapy for each disease site are clearly described, covering beam orientation, matching/patching field techniques, robustness planning, robustness plan evaluation, etc. The published data on the use of particle therapy for a given disease site are also concisely reported. In addition to fully meeting the needs of radiation oncologists, this "kn...

  6. Surfaced-based investigations plan, Volume 4: Yucca Mountain Project

    International Nuclear Information System (INIS)

    1988-12-01

    This document represents a detailed summary of design plans for surface-based investigations to be conducted for site characterization of the Yucca Mountain site. These plans are current as of December 1988. The description of surface-based site characterization activities contained in this document is intended to give all interested parties an understanding of the current plans for site characterization of Yucca Mountain. The maps presented in Volume 4 are products of the Geographic Information System (GIS) being used by the Yucca Mountain Project. The ARC/INFO GIS software, developed by Environmental Systems Research Institute, was used to digitize and process these SBIP maps. The maps were prepared using existing US Geological Survey (USGS) maps as a planimetric base. Roads and other surface features were interpreted from a variety of sources and entered into the GIS. Sources include the USGS maps, 1976 USGS orthophotoquads and aerial photography, 1986 and 1987 aerial photography, surveyed coordinates of field sites, and a combination of various maps, figures, descriptions and approximate coordinates of proposed locations for future activities

  7. The validation index: a new metric for validation of segmentation algorithms using two or more expert outlines with application to radiotherapy planning.

    Science.gov (United States)

    Juneja, Prabhjot; Evans, Philp M; Harris, Emma J

    2013-08-01

    Validation is required to ensure automated segmentation algorithms are suitable for radiotherapy target definition. In the absence of true segmentation, algorithmic segmentation is validated against expert outlining of the region of interest. Multiple experts are used to overcome inter-expert variability. Several approaches have been studied in the literature, but the most appropriate approach to combine the information from multiple expert outlines, to give a single metric for validation, is unclear. None consider a metric that can be tailored to case-specific requirements in radiotherapy planning. Validation index (VI), a new validation metric which uses experts' level of agreement was developed. A control parameter was introduced for the validation of segmentations required for different radiotherapy scenarios: for targets close to organs-at-risk and for difficult to discern targets, where large variation between experts is expected. VI was evaluated using two simulated idealized cases and data from two clinical studies. VI was compared with the commonly used Dice similarity coefficient (DSCpair - wise) and found to be more sensitive than the DSCpair - wise to the changes in agreement between experts. VI was shown to be adaptable to specific radiotherapy planning scenarios.

  8. Density overwrites of internal tumor volumes in intensity modulated proton therapy plans for mobile lung tumors

    Science.gov (United States)

    Botas, Pablo; Grassberger, Clemens; Sharp, Gregory; Paganetti, Harald

    2018-02-01

    The purpose of this study was to investigate internal tumor volume density overwrite strategies to minimize intensity modulated proton therapy (IMPT) plan degradation of mobile lung tumors. Four planning paradigms were compared for nine lung cancer patients. Internal gross tumor volume (IGTV) and internal clinical target volume (ICTV) structures were defined encompassing their respective volumes in every 4DCT phase. The paradigms use different planning CT (pCT) created from the average intensity projection (AIP) of the 4DCT, overwriting the density within the IGTV to account for movement. The density overwrites were: (a) constant filling with 100 HU (C100) or (b) 50 HU (C50), (c) maximum intensity projection (MIP) across phases, and (d) water equivalent path length (WEPL) consideration from beam’s-eye-view. Plans were created optimizing dose-influence matrices calculated with fast GPU Monte Carlo (MC) simulations in each pCT. Plans were evaluated with MC on the 4DCTs using a model of the beam delivery time structure. Dose accumulation was performed using deformable image registration. Interplay effect was addressed applying 10 times rescanning. Significantly less DVH metrics degradation occurred when using MIP and WEPL approaches. Target coverage (D99≥slant 70 Gy(RBE)) was fulfilled in most cases with MIP and WEPL (D{{99}WEPL}=69.2+/- 4.0 Gy (RBE)), keeping dose heterogeneity low (D5-D{{95}WEPL}=3.9+/- 2.0 Gy(RBE)). The mean lung dose was kept lowest by the WEPL strategy, as well as the maximum dose to organs at risk (OARs). The impact on dose levels in the heart, spinal cord and esophagus were patient specific. Overall, the WEPL strategy gives the best performance and should be preferred when using a 3D static geometry for lung cancer IMPT treatment planning. Newly available fast MC methods make it possible to handle long simulations based on 4D data sets to perform studies with high accuracy and efficiency, even prior to individual treatment planning.

  9. SeaWiFS Technical Report Series. Volume 42; Satellite Primary Productivity Data and Algorithm Development: A Science Plan for Mission to Planet Earth

    Science.gov (United States)

    Falkowski, Paul G.; Behrenfeld, Michael J.; Esaias, Wayne E.; Balch, William; Campbell, Janet W.; Iverson, Richard L.; Kiefer, Dale A.; Morel, Andre; Yoder, James A.; Hooker, Stanford B. (Editor); hide

    1998-01-01

    Two issues regarding primary productivity, as it pertains to the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Program and the National Aeronautics and Space Administration (NASA) Mission to Planet Earth (MTPE) are presented in this volume. Chapter 1 describes the development of a science plan for deriving primary production for the world ocean using satellite measurements, by the Ocean Primary Productivity Working Group (OPPWG). Chapter 2 presents discussions by the same group, of algorithm classification, algorithm parameterization and data availability, algorithm testing and validation, and the benefits of a consensus primary productivity algorithm.

  10. An improved distance-to-dose correlation for predicting bladder and rectum dose-volumes in knowledge-based VMAT planning for prostate cancer

    Science.gov (United States)

    Wall, Phillip D. H.; Carver, Robert L.; Fontenot, Jonas D.

    2018-01-01

    The overlap volume histogram (OVH) is an anatomical metric commonly used to quantify the geometric relationship between an organ at risk (OAR) and target volume when predicting expected dose-volumes in knowledge-based planning (KBP). This work investigated the influence of additional variables contributing to variations in the assumed linear DVH-OVH correlation for the bladder and rectum in VMAT plans of prostate patients, with the goal of increasing prediction accuracy and achievability of knowledge-based planning methods. VMAT plans were retrospectively generated for 124 prostate patients using multi-criteria optimization. DVHs quantified patient dosimetric data while OVHs quantified patient anatomical information. The DVH-OVH correlations were calculated for fractional bladder and rectum volumes of 30, 50, 65, and 80%. Correlations between potential influencing factors and dose were quantified using the Pearson product-moment correlation coefficient (R). Factors analyzed included the derivative of the OVH, prescribed dose, PTV volume, bladder volume, rectum volume, and in-field OAR volume. Out of the selected factors, only the in-field bladder volume (mean R  =  0.86) showed a strong correlation with bladder doses. Similarly, only the in-field rectal volume (mean R  =  0.76) showed a strong correlation with rectal doses. Therefore, an OVH formalism accounting for in-field OAR volumes was developed to determine the extent to which it improved the DVH-OVH correlation. Including the in-field factor improved the DVH-OVH correlation, with the mean R values over the fractional volumes studied improving from  -0.79 to  -0.85 and  -0.82 to  -0.86 for the bladder and rectum, respectively. A re-planning study was performed on 31 randomly selected database patients to verify the increased accuracy of KBP dose predictions by accounting for bladder and rectum volume within treatment fields. The in-field OVH led to significantly more precise

  11. SU-F-T-359: Incorporating Dose Volume Histogram Prediction Into Auto-Planning for Volumetric-Modulated Arc Therapy in Rectal Cancer

    International Nuclear Information System (INIS)

    Li, K; Chen, X; Wang, J; Lu, S; Chen, Y; Hu, W

    2016-01-01

    Purpose: To incorporate dose volume histogram (DVH) prediction into Auto-Planning for volumetric-modulated arc therapy (VMAT) treatment planning and investigate the benefit of this new technique for rectal cancer. Methods: Ninety clinically accepted VMAT plans for patients with rectal cancer were selected and trained in the RapidPlan for DVH prediction. Both internal and external validations were performed before implementing the prediction model. A new VMAT planning method (hybrid-VMAT) was created with combining the DVH prediction and Auto-Planning. For each new patient, the DVH will be predicted and individual DVH constrains will be obtained and were exported as the original optimization parameters to the Auto-Planning (Pinnacle3 treatment planning system, v9.10) for planning. A total of 20 rectal cancer patients previously treated with manual VMAT (manual-VMAT) plans were replanned using this new method. Dosimetric comparisons were performed between manual VMAT and new method plans. Results: Hybrid-VMAT shows similar PTV coverage to manual-VMAT in D2%, D98% and HI (p>0.05) and superior coverage in CI (p=0.000). For the bladder, the means of V40 and mean dose are 36.0% and 35.6Gy for hybrid-VMAT and 42% and 38.0Gy for the manual-VMAT. For the left (right) femur, the means of V30 and mean dose are 10.6% (11.6%) and 17.9Gy (19.2Gy) for the hybrid-VMAT and 25.6% (24.1%) and 27.3Gy (26.2Gy) for the manual-VMAT. The hybrid-VMAT has significantly improved the organs at risk sparing. Conclusion: The integration of DVH prediction and Auto-Planning significantly improve the VMAT plan quality in the rectal cancer radiotherapy. Our results show the benefit of the new method and will be further investigated in other tumor sites.

  12. SU-F-T-359: Incorporating Dose Volume Histogram Prediction Into Auto-Planning for Volumetric-Modulated Arc Therapy in Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, K; Chen, X; Wang, J; Lu, S; Chen, Y; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To incorporate dose volume histogram (DVH) prediction into Auto-Planning for volumetric-modulated arc therapy (VMAT) treatment planning and investigate the benefit of this new technique for rectal cancer. Methods: Ninety clinically accepted VMAT plans for patients with rectal cancer were selected and trained in the RapidPlan for DVH prediction. Both internal and external validations were performed before implementing the prediction model. A new VMAT planning method (hybrid-VMAT) was created with combining the DVH prediction and Auto-Planning. For each new patient, the DVH will be predicted and individual DVH constrains will be obtained and were exported as the original optimization parameters to the Auto-Planning (Pinnacle3 treatment planning system, v9.10) for planning. A total of 20 rectal cancer patients previously treated with manual VMAT (manual-VMAT) plans were replanned using this new method. Dosimetric comparisons were performed between manual VMAT and new method plans. Results: Hybrid-VMAT shows similar PTV coverage to manual-VMAT in D2%, D98% and HI (p>0.05) and superior coverage in CI (p=0.000). For the bladder, the means of V40 and mean dose are 36.0% and 35.6Gy for hybrid-VMAT and 42% and 38.0Gy for the manual-VMAT. For the left (right) femur, the means of V30 and mean dose are 10.6% (11.6%) and 17.9Gy (19.2Gy) for the hybrid-VMAT and 25.6% (24.1%) and 27.3Gy (26.2Gy) for the manual-VMAT. The hybrid-VMAT has significantly improved the organs at risk sparing. Conclusion: The integration of DVH prediction and Auto-Planning significantly improve the VMAT plan quality in the rectal cancer radiotherapy. Our results show the benefit of the new method and will be further investigated in other tumor sites.

  13. Considerations on the calculation of volumes in two planning systems; Consideraciones sobre el calculo de volumenes en dos sistemas de planificacion

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Tenedor Alonso, S.; Rincon Perez, M.; Penedo Cobos, J. M.; Garcia Castejon, M. A.

    2011-07-01

    The discrepancies in the calculation of the same volume between different planning systems impact on dose-volume histograms and therefore clinical assessment of dosimetry for patients. The transfer, by a local network, tomographic study (CT) and contours of critical organs of patients, between our two planning systems allows us to evaluate the calculation of identical volumes.

  14. SU-F-T-447: The Impact of Treatment Planning Methods On RapidPlan Modeling for Rectum Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lu, S; Peng, J; Li, K; Wang, J; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China)

    2016-06-15

    Purpose: To investigate the dose volume histogram (DVH) prediction varieties based on intensity modulate radiotherapy (IMRT) plan or volume arc modulate radiotherapy (VMAT) plan models on the RapidPlan. Methods: Two DVH prediction models were generated in this study, including an IMRT model trained from 83 IMRT rectum plans and a VMAT model trained from 60 VMAT rectum plans. In the internal validation, 20 plans from each training database were selected to verify the clinical feasibility of the model. Then, 10 IMRT plans (PIMRT-by-IMRT-model) generated from IMRT model and 10 IMRT plans generated from VMAT model (PIMRT-by-VMAT-model) were compared on the dose to organs at risk (OAR), which included bladder, left and right femoral heads. The similar comparison was also performed on the VMAT plans generated from IMRT model (PVMAT-by-IMRT-model) and VMAT plans generated from VMAT (PVMAT-by-VMAT-model) model. Results: For the internal validation, all plans from IMRT or VMAT model shows significantly improvement on OAR sparing compared with the corresponded clinical ones. Compared to the PIMRT-by-VMAT-model, the PIMRT-by-IMRT-model has a reduction of 6.90±3.87%(p<0.001) on V40 6.63±3.62%(p<0.001) on V45 and 4.74±2.26%(p<0.001) on V50 in bladder; and a mean dose reduction of 2.12±1.75Gy(p=0.004) and 2.84±1.53Gy(p<0.001) in right and left femoral head, respectively. There was no significant difference on OAR sparing between PVMAT-by-IMRT-model and PVMAT-by-VMAT-model. Conclusion: The IMRT model for the rectal cancer in the RapidPlan can be applied to for VMAT planning. However, the VMAT model is not suggested to use in the IMRT planning. Cautions should be taken that the planning model based on some technique may not feasible to other planning techniques.

  15. The dose-volume constraint satisfaction problem for inverse treatment planning with field segments

    International Nuclear Information System (INIS)

    Michalski, Darek; Xiao, Ying; Censor, Yair; Galvin, James M

    2004-01-01

    The prescribed goals of radiation treatment planning are often expressed in terms of dose-volume constraints. We present a novel formulation of a dose-volume constraint satisfaction search for the discretized radiation therapy model. This approach does not rely on any explicit cost function. Inverse treatment planning uses the aperture-based approach with predefined, according to geometric rules, segmental fields. The solver utilizes the simultaneous version of the cyclic subgradient projection algorithm. This is a deterministic iterative method designed for solving the convex feasibility problems. A prescription is expressed with the set of inequalities imposed on the dose at the voxel resolution. Additional constraint functions control the compliance with selected points of the expected cumulative dose-volume histograms. The performance of this method is tested on prostate and head-and-neck cases. The relationships with other models and algorithms of similar conceptual origin are discussed. The demonstrated advantages of the method are: the equivalence of the algorithmic and prescription parameters, the intuitive setup of free parameters, and the improved speed of the method as compared to similar iterative as well as other techniques. The technique reported here will deliver approximate solutions for inconsistent prescriptions

  16. Kilowatt isotope power system, Phase II Plan. Volume IV. Teledyne FSCD vs GDS

    Energy Technology Data Exchange (ETDEWEB)

    1978-03-15

    This Volume contains Teledyne's input to the Kilowatt Isotope Power System Phase II Plan. Included is a description of the Flight System Heat Generation System, Flight System Radiator, Thermal Insulation Stability, GDS Heat Generation System and GDS Radiator.

  17. Volume reduction of low-level contaminated metal waste by melting: selection of method and conceptual plan

    International Nuclear Information System (INIS)

    Copeland, G.L.; Heestand, R.L.; Mateer, R.S.

    1978-06-01

    A review of the literature and prior experience led to selection of induction melting as the most promising method for volume reduction of low-level transuranic contaminated metal waste. The literature indicates that melting with the appropriate slags significantly lowers the total contamination level of the metals by preferentially concentrating contaminants in the smaller volume of slag. Surface contamination not removed to the slag is diluted in the ingot and is contained uniformly in the metal. This dilution and decontamination offers the potential of lower cost disposal such as shallow burial rather than placement in a national repository. A processing plan is proposed as a model for economic analysis of the collection and volume reduction of contaminated metals. Further development is required to demonstrate feasibility of the plan

  18. Clinical implementation of dose-volume histogram predictions for organs-at-risk in IMRT planning

    International Nuclear Information System (INIS)

    Moore, K L; Appenzoller, L M; Tan, J; Michalski, J M; Thorstad, W L; Mutic, S

    2014-01-01

    True quality control (QC) of the planning process requires quantitative assessments of treatment plan quality itself, and QC in IMRT has been stymied by intra-patient anatomical variability and inherently complex three-dimensional dose distributions. In this work we describe the development of an automated system to reduce clinical IMRT planning variability and improve plan quality using mathematical models that predict achievable OAR DVHs based on individual patient anatomy. These models rely on the correlation of expected dose to the minimum distance from a voxel to the PTV surface, whereby a three-parameter probability distribution function (PDF) was used to model iso-distance OAR subvolume dose distributions. DVH models were obtained by fitting the evolution of the PDF with distance. Initial validation on clinical cohorts of 40 prostate and 24 head-and-neck plans demonstrated highly accurate model-based predictions for achievable DVHs in rectum, bladder, and parotid glands. By quantifying the integrated difference between candidate DVHs and predicted DVHs, the models correctly identified plans with under-spared OARs, validated by replanning all cases and correlating any realized improvements against the predicted gains. Clinical implementation of these predictive models was demonstrated in the PINNACLE treatment planning system by use of existing margin expansion utilities and the scripting functionality inherent to the system. To maintain independence from specific planning software, a system was developed in MATLAB to directly process DICOM-RT data. Both model training and patient-specific analyses were demonstrated with significant computational accelerations from parallelization.

  19. Impact of the accuracy of automatic tumour functional volume delineation on radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Le Maitre, Amandine; Hatt, Mathieu; Pradier, Olivier; Cheze-le Rest, Catherine; Visvikis, Dimitris

    2012-01-01

    Over the past few years several automatic and semi-automatic PET segmentation methods for target volume definition in radiotherapy have been proposed. The objective of this study is to compare different methods in terms of dosimetry. For such a comparison, a gold standard is needed. For this purpose, realistic GATE-simulated PET images were used. Three lung cases and three H and N cases were designed with various shapes, contrasts and heterogeneities. Four different segmentation approaches were compared: fixed and adaptive thresholds, a fuzzy C-mean and the fuzzy locally adaptive Bayesian method. For each of these target volumes, an IMRT treatment plan was defined. The different algorithms and resulting plans were compared in terms of segmentation errors and ground-truth volume coverage using different metrics (V 95 , D 95 , homogeneity index and conformity index). The major differences between the threshold-based methods and automatic methods occurred in the most heterogeneous cases. Within the two groups, the major differences occurred for low contrast cases. For homogeneous cases, equivalent ground-truth volume coverage was observed for all methods but for more heterogeneous cases, significantly lower coverage was observed for threshold-based methods. Our study demonstrates that significant dosimetry errors can be avoided by using more advanced image-segmentation methods. (paper)

  20. Development and Validation of a Gender Ideology Scale for Family Planning Services in Rural China

    Science.gov (United States)

    Yang, Xueyan; Li, Shuzhuo; Feldman, Marcus W.

    2013-01-01

    The objectives of this study are to develop a scale of gender role ideology appropriate for assessing Quality of Care in family planning services for rural China. Literature review, focus-group discussions and in-depth interviews with service providers and clients from two counties in eastern and western China, as well as experts’ assessments, were used to develop a scale for family planning services. Psychometric methodologies were applied to samples of 601 service clients and 541 service providers from a survey in a district in central China to validate its internal consistency, reliability, and construct validity with realistic and strategic dimensions. This scale is found to be reliable and valid, and has prospects for application both academically and practically in the field. PMID:23573222

  1. Guidelines for the verification and validation of expert system software and conventional software: Validation scenarios. Volume 6

    International Nuclear Information System (INIS)

    Mirsky, S.M.; Hayes, J.E.; Miller, L.A.

    1995-03-01

    This report is the sixth volume in a series of reports describing the results of the Expert System Verification and Validation (V ampersand V) project which is jointly funded by the US Nuclear Regulatory Commission and the Electric Power Research Institute. The ultimate objective is the formulation of guidelines for the V ampersand V of expert systems for use in nuclear power applications. This activity was concerned with the development of a methodology for selecting validation scenarios and subsequently applying it to two expert systems used for nuclear utility applications. Validation scenarios were defined and classified into five categories: PLANT, TEST, BASICS, CODE, and LICENSING. A sixth type, REGRESSION, is a composite of the others and refers to the practice of using trusted scenarios to ensure that modifications to software did not change unmodified functions. Rationale was developed for preferring scenarios selected from the categories in the order listed and for determining under what conditions to select scenarios from other types. A procedure incorporating all of the recommendations was developed as a generalized method for generating validation scenarios. The procedure was subsequently applied to two expert systems used in the nuclear industry and was found to be effective, given that an experienced nuclear engineer made the final scenario selections. A method for generating scenarios directly from the knowledge base component was suggested

  2. Guidelines for the verification and validation of expert system software and conventional software: Validation scenarios. Volume 6

    Energy Technology Data Exchange (ETDEWEB)

    Mirsky, S.M.; Hayes, J.E.; Miller, L.A. [Science Applications International Corp., McLean, VA (United States)

    1995-03-01

    This report is the sixth volume in a series of reports describing the results of the Expert System Verification and Validation (V&V) project which is jointly funded by the US Nuclear Regulatory Commission and the Electric Power Research Institute. The ultimate objective is the formulation of guidelines for the V&V of expert systems for use in nuclear power applications. This activity was concerned with the development of a methodology for selecting validation scenarios and subsequently applying it to two expert systems used for nuclear utility applications. Validation scenarios were defined and classified into five categories: PLANT, TEST, BASICS, CODE, and LICENSING. A sixth type, REGRESSION, is a composite of the others and refers to the practice of using trusted scenarios to ensure that modifications to software did not change unmodified functions. Rationale was developed for preferring scenarios selected from the categories in the order listed and for determining under what conditions to select scenarios from other types. A procedure incorporating all of the recommendations was developed as a generalized method for generating validation scenarios. The procedure was subsequently applied to two expert systems used in the nuclear industry and was found to be effective, given that an experienced nuclear engineer made the final scenario selections. A method for generating scenarios directly from the knowledge base component was suggested.

  3. Savannah River Site mixed waste Proposed Site Treatment Plan (PSTP). Volumes 1 and 2 and reference document: Revision 2

    International Nuclear Information System (INIS)

    Helmich, E.; Noller, D.K.; Wierzbicki, K.S.; Bailey, L.L.

    1995-01-01

    The DOE is required by the Resource Conservation and Recovery Act to prepare site treatment plans describing the development of treatment capacities and technologies for treating mixed waste. This proposed plan contains Savannah River Site's preferred options and schedules for constructing new facilities, and otherwise obtaining treatment for mixed wastes. The proposed plan consists of 2 volumes. Volume 1, Compliance Plan, identifies the capacity to be developed and the schedules as required. Volume 2, Background, provides a detailed discussion of the preferred options with technical basis, plus a description of the specific waste streams. Chapters are: Introduction; Methodology; Mixed low level waste streams; Mixed transuranic waste; High level waste; Future generation of mixed waste streams; Storage; Process for evaluation of disposal issues in support of the site treatment plans discussions; Treatment facilities and treatment technologies; Offsite waste streams for which SRS treatment is the Preferred Option (Naval reactor wastes); Summary information; and Acronyms and glossary. This revision does not contain the complete revised report, but only those pages that have been revised

  4. Sodium fast reactor safety and licensing research plan - Volume II

    International Nuclear Information System (INIS)

    Ludewig, H.; Powers, D.A.; Hewson, John C.; LaChance, Jeffrey L.; Wright, A.; Phillips, J.; Zeyen, R.; Clement, B.; Garner, Frank; Walters, Leon; Wright, Steve; Ott, Larry J.; Suo-Anttila, Ahti Jorma; Denning, Richard; Ohshima, Hiroyuki; Ohno, S.; Miyhara, S.; Yacout, Abdellatif; Farmer, M.; Wade, D.; Grandy, C.; Schmidt, R.; Cahalen, J.; Olivier, Tara Jean; Budnitz, R.; Tobita, Yoshiharu; Serre, Frederic; Natesan, Ken; Carbajo, Juan J.; Jeong, Hae-Yong; Wigeland, Roald; Corradini, Michael; Thomas, Justin; Wei, Tom; Sofu, Tanju; Flanagan, George F.; Bari, R.; Porter D.

    2012-01-01

    Expert panels comprised of subject matter experts identified at the U.S. National Laboratories (SNL, ANL, INL, ORNL, LBL, and BNL), universities (University of Wisconsin and Ohio State University), international agencies (IRSN, CEA, JAEA, KAERI, and JRC-IE) and private consultation companies (Radiation Effects Consulting) were assembled to perform a gap analysis for sodium fast reactor licensing. Expert-opinion elicitation was performed to qualitatively assess the current state of sodium fast reactor technologies. Five independent gap analyses were performed resulting in the following topical reports: (1) Accident Initiators and Sequences (i.e., Initiators/Sequences Technology Gap Analysis), (2) Sodium Technology Phenomena (i.e., Advanced Burner Reactor Sodium Technology Gap Analysis), (3) Fuels and Materials (i.e., Sodium Fast Reactor Fuels and Materials: Research Needs), (4) Source Term Characterization (i.e., Advanced Sodium Fast Reactor Accident Source Terms: Research Needs), and (5) Computer Codes and Models (i.e., Sodium Fast Reactor Gaps Analysis of Computer Codes and Models for Accident Analysis and Reactor Safety). Volume II of the Sodium Research Plan consolidates the five gap analysis reports produced by each expert panel, wherein the importance of the identified phenomena and necessities of further experimental research and code development were addressed. The findings from these five reports comprised the basis for the analysis in Sodium Fast Reactor Research Plan Volume I.

  5. Sodium fast reactor safety and licensing research plan. Volume II.

    Energy Technology Data Exchange (ETDEWEB)

    Ludewig, H. (Brokhaven National Laboratory, Upton, NY); Powers, D. A.; Hewson, John C.; LaChance, Jeffrey L.; Wright, A. (Argonne National Laboratory, Argonne, IL); Phillips, J.; Zeyen, R. (Institute for Energy Petten, Saint-Paul-lez-Durance, France); Clement, B. (IRSN/DPAM.SEMIC Bt 702, Saint-Paul-lez-Durance, France); Garner, Frank (Radiation Effects Consulting, Richland, WA); Walters, Leon (Advanced Reactor Concepts, Los Alamos, NM); Wright, Steve; Ott, Larry J. (Oak Ridge National Laboratory, Oak Ridge, TN); Suo-Anttila, Ahti Jorma; Denning, Richard (Ohio State University, Columbus, OH); Ohshima, Hiroyuki (Japan Atomic Energy Agency, Ibaraki, Japan); Ohno, S. (Japan Atomic Energy Agency, Ibaraki, Japan); Miyhara, S. (Japan Atomic Energy Agency, Ibaraki, Japan); Yacout, Abdellatif (Argonne National Laboratory, Argonne, IL); Farmer, M. (Argonne National Laboratory, Argonne, IL); Wade, D. (Argonne National Laboratory, Argonne, IL); Grandy, C. (Argonne National Laboratory, Argonne, IL); Schmidt, R.; Cahalen, J. (Argonne National Laboratory, Argonne, IL); Olivier, Tara Jean; Budnitz, R. (Lawrence Berkeley National Laboratory, Berkeley, CA); Tobita, Yoshiharu (Japan Atomic Energy Agency, Ibaraki, Japan); Serre, Frederic (Centre d' %C3%94etudes nucl%C3%94eaires de Cadarache, Cea, France); Natesan, Ken (Argonne National Laboratory, Argonne, IL); Carbajo, Juan J. (Oak Ridge National Laboratory, Oak Ridge, TN); Jeong, Hae-Yong (Korea Atomic Energy Research Institute, Daejeon, Korea); Wigeland, Roald (Idaho National Laboratory, Idaho Falls, ID); Corradini, Michael (University of Wisconsin-Madison, Madison, WI); Thomas, Justin (Argonne National Laboratory, Argonne, IL); Wei, Tom (Argonne National Laboratory, Argonne, IL); Sofu, Tanju (Argonne National Laboratory, Argonne, IL); Flanagan, George F. (Oak Ridge National Laboratory, Oak Ridge, TN); Bari, R. (Brokhaven National Laboratory, Upton, NY); Porter D. (Idaho National Laboratory, Idaho Falls, ID); Lambert, J. (Argonne National Laboratory, Argonne, IL); Hayes, S. (Idaho National Laboratory, Idaho Falls, ID); Sackett, J. (Idaho National Laboratory, Idaho Falls, ID); Denman, Matthew R.

    2012-05-01

    Expert panels comprised of subject matter experts identified at the U.S. National Laboratories (SNL, ANL, INL, ORNL, LBL, and BNL), universities (University of Wisconsin and Ohio State University), international agencies (IRSN, CEA, JAEA, KAERI, and JRC-IE) and private consultation companies (Radiation Effects Consulting) were assembled to perform a gap analysis for sodium fast reactor licensing. Expert-opinion elicitation was performed to qualitatively assess the current state of sodium fast reactor technologies. Five independent gap analyses were performed resulting in the following topical reports: (1) Accident Initiators and Sequences (i.e., Initiators/Sequences Technology Gap Analysis), (2) Sodium Technology Phenomena (i.e., Advanced Burner Reactor Sodium Technology Gap Analysis), (3) Fuels and Materials (i.e., Sodium Fast Reactor Fuels and Materials: Research Needs), (4) Source Term Characterization (i.e., Advanced Sodium Fast Reactor Accident Source Terms: Research Needs), and (5) Computer Codes and Models (i.e., Sodium Fast Reactor Gaps Analysis of Computer Codes and Models for Accident Analysis and Reactor Safety). Volume II of the Sodium Research Plan consolidates the five gap analysis reports produced by each expert panel, wherein the importance of the identified phenomena and necessities of further experimental research and code development were addressed. The findings from these five reports comprised the basis for the analysis in Sodium Fast Reactor Research Plan Volume I.

  6. Decomposition analysis of differential dose volume histograms

    International Nuclear Information System (INIS)

    Heuvel, Frank van den

    2006-01-01

    Dose volume histograms are a common tool to assess the value of a treatment plan for various forms of radiation therapy treatment. The purpose of this work is to introduce, validate, and apply a set of tools to analyze differential dose volume histograms by decomposing them into physically and clinically meaningful normal distributions. A weighted sum of the decomposed normal distributions (e.g., weighted dose) is proposed as a new measure of target dose, rather than the more unstable point dose. The method and its theory are presented and validated using simulated distributions. Additional validation is performed by analyzing simple four field box techniques encompassing a predefined target, using different treatment energies inside a water phantom. Furthermore, two clinical situations are analyzed using this methodology to illustrate practical usefulness. A comparison of a treatment plan for a breast patient using a tangential field setup with wedges is compared to a comparable geometry using dose compensators. Finally, a normal tissue complication probability (NTCP) calculation is refined using this decomposition. The NTCP calculation is performed on a liver as organ at risk in a treatment of a mesothelioma patient with involvement of the right lung. The comparison of the wedged breast treatment versus the compensator technique yields comparable classical dose parameters (e.g., conformity index ≅1 and equal dose at the ICRU dose point). The methodology proposed here shows a 4% difference in weighted dose outlining the difference in treatment using a single parameter instead of at least two in a classical analysis (e.g., mean dose, and maximal dose, or total dose variance). NTCP-calculations for the mesothelioma case are generated automatically and show a 3% decrease with respect to the classical calculation. The decrease is slightly dependant on the fractionation and on the α/β-value utilized. In conclusion, this method is able to distinguish clinically

  7. Building Technologies Program Multi-Year Program Plan Technology Validation and Market Introduction 2008

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2008-01-01

    Building Technologies Program Multi-Year Program Plan 2008 for technology validation and market introduction, including ENERGY STAR, building energy codes, technology transfer application centers, commercial lighting initiative, EnergySmart Schools, EnergySmar

  8. Clinical variability of target volume description and treatment plans in conformal radiotherapy in muscle invasive bladder cancer

    International Nuclear Information System (INIS)

    Logue, John P; Sharrock, Carole L; Cowan, Richard A.; Read, Graham; Marrs, Julie; Mott, David

    1996-01-01

    Purpose/Objective: The delineation of tumor and the production of a treatment plan to encompass this is the prime step in radiotherapy planning. Conformal radiotherapy is developing rapidly and although plentiful research has addressed the implementation of the radiotherapy prescription, scant attention has been made to the fundamental step of production, by the clinician, of an appropriate target volume. As part of an ongoing randomized trial of conformal radiotherapy, in bladder cancer, we have therefore assessed the interphysician variability of radiologists and radiation oncologists (RO) in assessing Gross Tumor Volume(GTV) (ICRU 50) and the adherence of the radiation oncologists to the study protocol of producing a Planning Target Volume (PTV). Materials and Methods: Four patients with T3 carcinoma of bladder who had been entered into the trial were identified. The clinical details, MR scans and CT scans were made available. Eight RO and 3 dedicated diagnostic oncology radiologists were invited to directly outline the GTV onto CT images on a planning computer consul. The RO in addition created a PTV following the trial protocol of 15mm margin around the GTV. Three RO sub-specialized in Urological radiotherapy; all RO had completed training. Volumes were produced, for each clinician, and comparison of these volumes and their isocenters were analyzed. In addition the margins allowed were measured and compared. Results: There was a maximum variation ratio (largest to smallest volume outlined) of the GTV in the four cases of 1.74 among radiologists and 3.74 among oncologists. There was a significant difference (p=0.01) in mean GTV between RO and the radiologists. The mean GTV of the RO exceeded the radiologists by a factor of 1.29 with a mean difference of 13.4 cm 3 The between observer variance within speciality comprised only 9.9% of the total variance in the data having accounted for case and observers speciality. The variation ratio in PTV among oncologists

  9. A Comprehensive Plan for the Long-Term Calibration and Validation of Oceanic Biogeochemical Satellite Data

    Science.gov (United States)

    Hooker, Stanford B.; McClain, Charles R.; Mannino, Antonio

    2007-01-01

    The primary objective of this planning document is to establish a long-term capability and validating oceanic biogeochemical satellite data. It is a pragmatic solution to a practical problem based primarily o the lessons learned from prior satellite missions. All of the plan's elements are seen to be interdependent, so a horizontal organizational scheme is anticipated wherein the overall leadership comes from the NASA Ocean Biology and Biogeochemistry (OBB) Program Manager and the entire enterprise is split into two components of equal sature: calibration and validation plus satellite data processing. The detailed elements of the activity are based on the basic tasks of the two main components plus the current objectives of the Carbon Cycle and Ecosystems Roadmap. The former is distinguished by an internal core set of responsibilities and the latter is facilitated through an external connecting-core ring of competed or contracted activities. The core elements for the calibration and validation component include a) publish protocols and performance metrics; b) verify uncertainty budgets; c) manage the development and evaluation of instrumentation; and d) coordinate international partnerships. The core elements for the satellite data processing component are e) process and reprocess multisensor data; f) acquire, distribute, and archive data products; and g) implement new data products. Both components have shared responsibilities for initializing and temporally monitoring satellite calibration. Connecting-core elements include (but are not restricted to) atmospheric correction and characterization, standards and traceability, instrument and analysis round robins, field campaigns and vicarious calibration sites, in situ database, bio-optical algorithm (and product) validation, satellite characterization and vicarious calibration, and image processing software. The plan also includes an accountability process, creating a Calibration and Validation Team (to help manage

  10. Navigator channel adaptation to reconstruct three dimensional heart volumes from two dimensional radiotherapy planning data

    International Nuclear Information System (INIS)

    Ng, Angela; Nguyen, Thao-Nguyen; Moseley, Joanne L; Hodgson, David C; Sharpe, Michael B; Brock, Kristy K

    2012-01-01

    Biologically-based models that utilize 3D radiation dosimetry data to estimate the risk of late cardiac effects could have significant utility for planning radiotherapy in young patients. A major challenge arises from having only 2D treatment planning data for patients with long-term follow-up. In this study, we evaluate the accuracy of an advanced deformable image registration (DIR) and navigator channels (NC) adaptation technique to reconstruct 3D heart volumes from 2D radiotherapy planning images for Hodgkin's Lymphoma (HL) patients. Planning CT images were obtained for 50 HL patients who underwent mediastinal radiotherapy. Twelve image sets (6 male, 6 female) were used to construct a male and a female population heart model, which was registered to 23 HL 'Reference' patients' CT images using a DIR algorithm, MORFEUS. This generated a series of population-to-Reference patient specific 3D deformation maps. The technique was independently tested on 15 additional 'Test' patients by reconstructing their 3D heart volumes using 2D digitally reconstructed radiographs (DRR). The technique involved: 1) identifying a matching Reference patient for each Test patient using thorax measurements, 2) placement of six NCs on matching Reference and Test patients' DRRs to capture differences in significant heart curvatures, 3) adapting the population-to-Reference patient-specific deformation maps to generate population-to-Test patient-specific deformation maps using linear and bilinear interpolation methods, 4) applying population-to-Test patient specific deformation to the population model to reconstruct Test-patient specific 3D heart models. The percentage volume overlap between the NC-adapted reconstruction and actual Test patient's true heart volume was calculated using the Dice coefficient. The average Dice coefficient expressed as a percentage between the NC-adapted and actual Test model was 89.4 ± 2.8%. The modified NC adaptation

  11. A dose-volume histogram based decision-support system for dosimetric comparison of radiotherapy treatment plans

    International Nuclear Information System (INIS)

    Alfonso, J. C. L.; Herrero, M. A.; Núñez, L.

    2015-01-01

    The choice of any radiotherapy treatment plan is usually made after the evaluation of a few preliminary isodose distributions obtained from different beam configurations. Despite considerable advances in planning techniques, such final decision remains a challenging task that would greatly benefit from efficient and reliable assessment tools. For any dosimetric plan considered, data on dose-volume histograms supplied by treatment planning systems are used to provide estimates on planning target coverage as well as on sparing of organs at risk and the remaining healthy tissue. These partial metrics are then combined into a dose distribution index (DDI), which provides a unified, easy-to-read score for each competing radiotherapy plan. To assess the performance of the proposed scoring system, DDI figures for fifty brain cancer patients were retrospectively evaluated. Patients were divided in three groups depending on tumor location and malignancy. For each patient, three tentative plans were designed and recorded during planning, one of which was eventually selected for treatment. We thus were able to compare the plans with better DDI scores and those actually delivered. When planning target coverage and organs at risk sparing are considered as equally important, the tentative plan with the highest DDI score is shown to coincide with that actually delivered in 32 of the 50 patients considered. In 15 (respectively 3) of the remaining 18 cases, the plan with highest DDI value still coincides with that actually selected, provided that organs at risk sparing is given higher priority (respectively, lower priority) than target coverage. DDI provides a straightforward and non-subjective tool for dosimetric comparison of tentative radiotherapy plans. In particular, DDI readily quantifies differences among competing plans with similar-looking dose-volume histograms and can be easily implemented for any tumor type and localization, irrespective of the planning system and

  12. SU-F-T-617: Remotely Pre-Planned Stereotactic Ablative Radiation Therapy: Validation of Treatment Plan Quality

    International Nuclear Information System (INIS)

    Juang, T; Bush, K; Loo, B; Gensheimer, M

    2016-01-01

    Purpose: We propose a workflow to improve access to stereotactic ablative radiation therapy (SABR) for rural patients. When implemented, a separate trip to the central facility for simulation can be eliminated. Two elements are required: (1) Fabrication of custom immobilization devices to match positioning on prior diagnostic CT (dxCT). (2) Remote radiation pre-planning on dxCT, with transfer of contours/plan to simulation CT (simCT) and initiation of treatment same-day or next day. In this retrospective study, we validated part 2 of the workflow using patients already treated with SABR for upper lobe lung tumors. Methods: Target/normal structures were contoured on dxCT; a plan was created and approved by the physician. Structures were transferred to simCT using deformable image registration and the plan was re-optimized on simCT. Plan quality was evaluated through comparison to gold-standard structures contoured on simCT and a gold-standard plan based on these structures. Workflow-generated plan quality in this study represents a worst-case scenario as these patients were not treated using custom immobilization to match dxCT position as would be done when the workflow is implemented clinically. Results: 5/6 plans created through the pre-planning workflow were clinically acceptable. For all six plans, the gold-standard GTV received full prescription dose, along with median PTV V95%=95.2% and median PTV D95%=95.4%. Median GTV DSC=0.80, indicating high degree of similarity between the deformed and gold-standard GTV contours despite small GTV sizes (mean=3.0cc). One outlier (DSC=0.49) resulted in inadequate PTV coverage (V95%=62.9%) in the workflow plan; in clinical practice, this mismatch between deformed/gold-standard GTV would be revised by the physician after deformable registration. For all patients, normal tissue doses were comparable to the gold-standard plan and well within constraints. Conclusion: Pre-planning SABR cases on diagnostic imaging generated

  13. Validity and reliability of a novel 3D scanner for assessment of the shape and volume of amputees' residual limb models.

    Directory of Open Access Journals (Sweden)

    Elena Seminati

    Full Text Available Objective assessment methods to monitor residual limb volume following lower-limb amputation are required to enhance practitioner-led prosthetic fitting. Computer aided systems, including 3D scanners, present numerous advantages and the recent Artec Eva scanner, based on laser free technology, could potentially be an effective solution for monitoring residual limb volumes.The aim of this study was to assess the validity and reliability of the Artec Eva scanner (practical measurement against a high precision laser 3D scanner (criterion measurement for the determination of residual limb model shape and volume.Three observers completed three repeat assessments of ten residual limb models, using both the scanners. Validity of the Artec Eva scanner was assessed (mean percentage error <2% and Bland-Altman statistics were adopted to assess the agreement between the two scanners. Intra and inter-rater reliability (repeatability coefficient <5% of the Artec Eva scanner was calculated for measuring indices of residual limb model volume and shape (i.e. residual limb cross sectional areas and perimeters.Residual limb model volumes ranged from 885 to 4399 ml. Mean percentage error of the Artec Eva scanner (validity was 1.4% of the criterion volumes. Correlation coefficients between the Artec Eva and the Romer determined variables were higher than 0.9. Volume intra-rater and inter-rater reliability coefficients were 0.5% and 0.7%, respectively. Shape percentage maximal error was 2% at the distal end of the residual limb, with intra-rater reliability coefficients presenting the lowest errors (0.2%, both for cross sectional areas and perimeters of the residual limb models.The Artec Eva scanner is a valid and reliable method for assessing residual limb model shapes and volumes. While the method needs to be tested on human residual limbs and the results compared with the current system used in clinical practice, it has the potential to quantify shape and volume

  14. 242-A Evaporator quality assurance plan. Revision 2

    International Nuclear Information System (INIS)

    Basra, T.S.

    1995-01-01

    The purpose of this quality assurance project plan (Plan) is to provide requirements for activities pertaining to sampling, shipping, and analyses associated with candidate feed tank samples for the 242-A Evaporator project. The purpose of the 242-A Evaporator project is to reduce the volume of aqueous waste in the Double Shell Tank (DST) System and will result in considerable savings to the disposal of mixed waste. The 242-A Evaporator feed stream originates from DSTs identified as candidate feed tanks. The 242-A Evaporator reduces the volume of aqueous waste contained in DSTs by boiling off water and sending the condensate (called process condensate) to the Liquid Effluent Retention Facility (LEPF) storage basin where it is stored prior to treatment in the Effluent Treatment Facility (ETF). The objective of this quality assurance project plan is to provide the planning, implementation, and assessment of sample collection and analysis, data issuance, and validation activities for the candidate feed tanks

  15. Test plan for validation of the radiative transfer equation.

    Energy Technology Data Exchange (ETDEWEB)

    Ricks, Allen Joseph; Grasser, Thomas W.; Kearney, Sean Patrick; Jernigan, Dann A.; Blanchat, Thomas K.

    2010-09-01

    As the capabilities of numerical simulations increase, decision makers are increasingly relying upon simulations rather than experiments to assess risks across a wide variety of accident scenarios including fires. There are still, however, many aspects of fires that are either not well understood or are difficult to treat from first principles due to the computational expense. For a simulation to be truly predictive and to provide decision makers with information which can be reliably used for risk assessment the remaining physical processes must be studied and suitable models developed for the effects of the physics. A set of experiments are outlined in this report which will provide soot volume fraction/temperature data and heat flux (intensity) data for the validation of models for the radiative transfer equation. In addition, a complete set of boundary condition measurements will be taken to allow full fire predictions for validation of the entire fire model. The experiments will be performed with a lightly-sooting liquid hydrocarbon fuel fire in the fully turbulent scale range (2 m diameter).

  16. Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4, Volume IV: Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols

    Science.gov (United States)

    Mueller, J. L.; Fargion, G. S.; McClain, C. R. (Editor); Pegau, S.; Zanefeld, J. R. V.; Mitchell, B. G.; Kahru, M.; Wieland, J.; Stramska, M.

    2003-01-01

    This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparision and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background, and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 is entirely superseded by the six volumes of Revision 4 listed above.

  17. Savannah River Site Environmental Monitoring Plan. Volume 1, Section 1000 Addendum: Revision 3

    International Nuclear Information System (INIS)

    Jannik, G.T.

    1994-01-01

    This document -- the Savannah River Site Environmental Monitoring Plan (SRS EM Plan) -- has been prepared according to guidance contained in the DOE 5400 Series orders, in 10 CFR 834, and in DOE/EH-0173T, Environmental Regulatory Guide for Radiological Effluent Monitoring and environmental Surveillance [DOE, 1991]. The SRS EM Plan's purpose is to define the criteria, regulations, and guideline requirements with which SRS will comply. These criteria and requirements are applicable to environmental monitoring activities performed in support of the SRS Environmental Monitoring Program (SRS EM Program), WSRC-3Q1-2, Volume 1, Section 1100. They are not applicable to monitoring activities utilized exclusively for process monitoring/control. The environmental monitoring program requirements documented in the SRS EM Plan incorporate all applicable should requirements of DOE/EH-0173T and expand upon them to include nonradiological environmental monitoring program requirements

  18. Semiautomatic regional segmentation to measure orbital fat volumes in thyroid-associated ophthalmopathy. A validation study.

    Science.gov (United States)

    Comerci, M; Elefante, A; Strianese, D; Senese, R; Bonavolontà, P; Alfano, B; Bonavolontà, B; Brunetti, A

    2013-08-01

    This study was designed to validate a novel semi-automated segmentation method to measure regional intra-orbital fat tissue volume in Graves' ophthalmopathy. Twenty-four orbits from 12 patients with Graves' ophthalmopathy, 24 orbits from 12 controls, ten orbits from five MRI study simulations and two orbits from a digital model were used. Following manual region of interest definition of the orbital volumes performed by two operators with different levels of expertise, an automated procedure calculated intra-orbital fat tissue volumes (global and regional, with automated definition of four quadrants). In patients with Graves' disease, clinical activity score and degree of exophthalmos were measured and correlated with intra-orbital fat volumes. Operator performance was evaluated and statistical analysis of the measurements was performed. Accurate intra-orbital fat volume measurements were obtained with coefficients of variation below 5%. The mean operator difference in total fat volume measurements was 0.56%. Patients had significantly higher intra-orbital fat volumes than controls (p<0.001 using Student's t test). Fat volumes and clinical score were significantly correlated (p<0.001). The semi-automated method described here can provide accurate, reproducible intra-orbital fat measurements with low inter-operator variation and good correlation with clinical data.

  19. Poster - 36: Effect of Planning Target Volume Coverage on the Dose Delivered in Lung Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dekker, Chris; Wierzbicki, Marcin [McMaster University, Juravinski Cancer Centre (Canada)

    2016-08-15

    Purpose: In lung radiotherapy, breathing motion may be encompassed by contouring the internal target volume (ITV). Remaining uncertainties are included in a geometrical expansion to the planning target volume (PTV). In IMRT, the treatment is then optimized until a desired PTV fraction is covered by the appropriate dose. The resulting beams often carry high fluence in the PTV margin to overcome low lung density and to generate steep dose gradients. During treatment, the high density tumour can enter the PTV margin, potentially increasing target dose. Thus, planning lung IMRT with a reduced PTV dose may still achieve the desired ITV dose during treatment. Methods: A retrospective analysis was carried out with 25 IMRT plans prescribed to 63 Gy in 30 fractions. The plans were re-normalized to cover various fractions of the PTV by different isodose lines. For each case, the isocentre was moved using 125 shifts derived from all 3D combinations of 0 mm, (PTV margin - 1 mm), and PTV margin. After each shift, the dose was recomputed to approximate the delivered dose. Results and Conclusion: Our plans typically cover 95% of the PTV by 95% of the dose. Reducing the PTV covered to 94% did not significantly reduce the delivered ITV doses for (PTV margin - 1 mm) shifts. Target doses were reduced significantly for all other shifts and planning goals studied. Thus, a reduced planning goal will likely deliver the desired target dose as long as the ITV rarely enters the last mm of the PTV margin.

  20. Influence of volumes of prostate, rectum, and bladder on treatment planning CT on interfraction prostate shifts during ultrasound image-guided IMRT

    International Nuclear Information System (INIS)

    Reddy, Nandanuri M. S.; Nori, Dattatreyudu; Sartin, William; Maiorano, Samuel; Modena, Jennifer; Mazur, Andrej; Osian, Adrian; Sood, Brijmohan; Ravi, Akkamma; Sampath, Seshadri; Lange, Christopher S.

    2009-01-01

    Purpose: The purpose of this study was to analyze the relationship between prostate, bladder, and rectum volumes on treatment planning CT day and prostate shifts in the XYZ directions on treatment days. Methods: Prostate, seminal vesicles, bladder, and rectum were contoured on CT images obtained in supine position. Intensity modulated radiation therapy plans was prepared. Contours were exported to BAT-ultrasound imaging system. Patients were positioned on the couch using skin marks. An ultrasound probe was used to obtain ultrasound images of prostate, bladder, and rectum, which were aligned with CT images. Couch shifts in the XYZ directions as recommended by BAT system were made and recorded. 4698 couch shifts for 42 patients were analyzed to study the correlations between interfraction prostate shifts vs bladder, rectum, and prostate volumes on planning CT. Results: Mean and range of volumes (cc): Bladder: 179 (42-582), rectum: 108 (28-223), and prostate: 55 (21-154). Mean systematic prostate shifts were (cm, ±SD) right and left lateral: -0.047±0.16 (-0.361-0.251), anterior and posterior: 0.14±0.3 (-0.466-0.669), and superior and inferior: 0.19±0.26 (-0.342-0.633). Bladder volume was not correlated with lateral, anterior/posterior, and superior/inferior prostate shifts (P>0.2). Rectal volume was correlated with anterior/posterior (P 0.2). The smaller the rectal volume or cross sectional area, the larger was the prostate shift anteriorly and vice versa (P 0.2). The smaller the prostate volume, the larger was prostate shift superiorly and vice versa (P<0.05). Conclusions: Prostate and rectal volumes, but not bladder volumes, on treatment planning CT influenced prostate position on treatment fractions. Daily image-guided adoptive radiotherapy would be required for patients with distended or empty rectum on planning CT to reduce rectal toxicity in the case of empty rectum and to minimize geometric miss of prostate.

  1. Point-to-Point! Validation of the Small Aircraft Transportation System Higher Volume Operations Concept

    Science.gov (United States)

    Williams, Daniel M.

    2006-01-01

    Described is the research process that NASA researchers used to validate the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept. The four phase building-block validation and verification process included multiple elements ranging from formal analysis of HVO procedures to flight test, to full-system architecture prototype that was successfully shown to the public at the June 2005 SATS Technical Demonstration in Danville, VA. Presented are significant results of each of the four research phases that extend early results presented at ICAS 2004. HVO study results have been incorporated into the development of the Next Generation Air Transportation System (NGATS) vision and offer a validated concept to provide a significant portion of the 3X capacity improvement sought after in the United States National Airspace System (NAS).

  2. WE-B-304-03: Biological Treatment Planning

    International Nuclear Information System (INIS)

    Orton, C.

    2015-01-01

    The ultimate goal of radiotherapy treatment planning is to find a treatment that will yield a high tumor control probability (TCP) with an acceptable normal tissue complication probability (NTCP). Yet most treatment planning today is not based upon optimization of TCPs and NTCPs, but rather upon meeting physical dose and volume constraints defined by the planner. It has been suggested that treatment planning evaluation and optimization would be more effective if they were biologically and not dose/volume based, and this is the claim debated in this month’s Point/Counterpoint. After a brief overview of biologically and DVH based treatment planning by the Moderator Colin Orton, Joseph Deasy (for biological planning) and Charles Mayo (against biological planning) will begin the debate. Some of the arguments in support of biological planning include: this will result in more effective dose distributions for many patients DVH-based measures of plan quality are known to have little predictive value there is little evidence that either D95 or D98 of the PTV is a good predictor of tumor control sufficient validated outcome prediction models are now becoming available and should be used to drive planning and optimization Some of the arguments against biological planning include: several decades of experience with DVH-based planning should not be discarded we do not know enough about the reliability and errors associated with biological models the radiotherapy community in general has little direct experience with side by side comparisons of DVH vs biological metrics and outcomes it is unlikely that a clinician would accept extremely cold regions in a CTV or hot regions in a PTV, despite having acceptable TCP values Learning Objectives: To understand dose/volume based treatment planning and its potential limitations To understand biological metrics such as EUD, TCP, and NTCP To understand biologically based treatment planning and its potential limitations

  3. Viability Assessment of a Repository at Yucca Mountain. Volume 4: License Application Plan and Costs

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-12-01

    Volume 4 provides the DOE plan and cost estimate for the remaining work necessary to proceed from completing this VA to submitting an LA to NRC. This work includes preparing an EIS and evaluating the suitability of the site. Both items are necessary components of the documentation required to support a decision in 2001 by the Secretary of Energy on whether or not to recommend that the President approve the site for development as a repository. If the President recommends the site to Congress and the site designation becomes effective, then DOE will submit the LA to NRC in 2002 for authorization to construct the repository. The work described in Volume 4 constitutes the last step in the characterization of the Yucca Mountain site and the design and evaluation of the performance of a repository system in the geologic setting of this site. The plans in this volume for the next 4 years' work are based on the results of the previous 15 years' work, as reported in Volumes 1, 2, and 3 of this VA. Volume 1 summarizes what DOE has learned to date about the Yucca Mountain site. Volume 2 describes the current, reference repository design, several design options that might enhance the performance of the reference design, and several alternative designs that represent substantial departures from the reference design. Volume 2 also summarizes the results of tests of candidate materials for waste packages and for support of the tunnels into which waste would be emplaced. Volume 3 provides the results of the latest performance assessments undertaken to evaluate the performance of the design in the geologic setting of Yucca Mountain. The results described in Volumes 1, 2, and 3 provide the basis for identifying and prioritizing the work described in this volume. DOE believes that the planned work, together with the results of previous work, will be sufficient to support a site suitability evaluation for site recommendation and, if the site is recommended and designated, a

  4. Optimization of stereotactically-guided conformal treatment planning of sellar and parasellar tumors, based on normal brain dose volume histograms

    International Nuclear Information System (INIS)

    Perks, Julian R.; Jalali, Rakesh; Cosgrove, Vivian P.; Adams, Elizabeth J.; Shepherd, Stephen F.; Warrington, Alan P.; Brada, Michael

    1999-01-01

    Purpose: To investigate the optimal treatment plan for stereo tactically-guided conformal radiotherapy (SCRT) of sellar and parasellar lesions, with respect to sparing normal brain tissue, in the context of routine treatment delivery, based on dose volume histogram analysis. Methods and Materials: Computed tomography (CT) data sets for 8 patients with sellar- and parasellar-based tumors (6 pituitary adenomas and 2 meningiomas) have been used in this study. Treatment plans were prepared for 3-coplanar and 3-, 4-, 6-, and 30-noncoplanar-field arrangements to obtain 95% isodose coverage of the planning target volume (PTV) for each plan. Conformal shaping was achieved by customized blocks generated with the beams eye view (BEV) facility. Dose volume histograms (DVH) were calculated for the normal brain (excluding the PTV), and comparisons made for normal tissue sparing for all treatment plans at ≥80%, ≥60%, and ≥40% of the prescribed dose. Results: The mean volume of normal brain receiving ≥80% and ≥60% of the prescribed dose decreased by 22.3% (range 14.8-35.1%, standard deviation σ = 7.5%) and 47.6% (range 25.8-69.1%, σ 13.2%), respectively, with a 4-field noncoplanar technique when compared with a conventional 3-field coplanar technique. Adding 2 further fields, from 4-noncoplanar to 6-noncoplanar fields reduced the mean normal brain volume receiving ≥80% of the prescribed dose by a further 4.1% (range -6.5-11.8%, σ = 6.4%), and the volume receiving ≥60% by 3.3% (range -5.5-12.2%, σ = 5.4%), neither of which were statistically significant. Each case must be considered individually however, as a wide range is seen in the volume spared when increasing the number of fields from 4 to 6. Comparing the 4- and 6-field noncoplanar techniques to a 30-field conformal field approach (simulating a dynamic arc plan) revealed near-equivalent normal tissue sparing. Conclusion: Four to six widely spaced, fixed-conformal fields provide the optimum class solution

  5. Target volume definition with 18F-FDG PET-CT in radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Carson, K. J.; Hanna, G. G.; Hounsell, A. R.

    2011-01-01

    There is considerable interest in using 18F -Fluorodeoxyglucose (FDG) positron emission tomography (PET) images for radiotherapy treatment planning (RTF) purposes, and in particular for defining target volumes. This is a rapidly evolving subject and this review describes the background to this application of PET imaging and discusses the issues involved. (authors)

  6. Federal Facilities Compliance Act, Draft Site Treatment Plan: Compliance Plan Volume. Part 2, Volume 2

    International Nuclear Information System (INIS)

    1994-01-01

    This document presents the details of the implementation of the Site Treatment Plan developed by Ames Laboratory in compliance with the Federal Facilities Compliance Act. Topics discussed in this document include: implementation of the plan; milestones; annual updates to the plan; inclusion of new waste streams; modifications of the plan; funding considerations; low-level mixed waste treatment plan and schedules; and TRU mixed waste streams

  7. Tank waste source term inventory validation. Volume 1. Letter report

    International Nuclear Information System (INIS)

    Brevick, C.H.; Gaddis, L.A.; Johnson, E.D.

    1995-01-01

    The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories. This document is Volume I of the Letter Report entitled Tank Waste Source Term Inventory Validation

  8. Assessment of pulmonary vasculature volume with automated threshold-based 3D quantitative CT volumetry: In vitro and in vivo validation

    International Nuclear Information System (INIS)

    Liu Jingzhe; Wu Qingyu; Xu Yufeng; Bai Yan; Liu Zhibo; Li Hongyin; Zhu Jiemin

    2012-01-01

    Objectives: To validate the ability of threshold-based 3D CT volumetry to enable measurement of volume of visible pulmonary vessels on CT. Materials and methods: In vivo, 3D CT volumetry was validated in seven phantoms that consisted of silicone tubes embedded in a foam block. With the true volume value as reference standard, the accuracy of CT measurement at various lower thresholds of −600 HU, −500 HU, −300 HU and −200 HU were compared. The volume measurements obtained when filled with varied concentration of iodinated contrast media (1:100, 1:200 and 1:500) were also compared. In vivo validation was performed in sixteen patients (9 men, 7 women; mean age, 52.1 years). Inter-scan and inter-observer agreement and reproducibility for pulmonary vasculature volume measurement were evaluated with Bland–Altman analysis. Results: In vitro, the mean value measured under lower threshold of −300 HU (relative error = 1.5%) were the closest to the true values and have no significant difference (P = 0.375). There were no significant differences among the phantom measurement values with different filled concentration (1:100, 1:200 and 1:500). In vivo, the inter-scan reproducibility of volume measurements was good, with a correlation coefficient of 0.82 and ICC (intraclass correlation coefficient) of 0.86. Inter-observer agreement was excellent with a correlation coefficient of 0.91 and ICC of 0.95. Conclusions: The threshold-based 3D quantitative CT volumetry enables accurate and reproducible measurement of pulmonary vessels volume.

  9. Experimental validation of heterogeneity-corrected dose-volume prescription on respiratory-averaged CT images in stereotactic body radiotherapy for moving tumors

    International Nuclear Information System (INIS)

    Nakamura, Mitsuhiro; Miyabe, Yuki; Matsuo, Yukinori; Kamomae, Takeshi; Nakata, Manabu; Yano, Shinsuke; Sawada, Akira; Mizowaki, Takashi; Hiraoka, Masahiro

    2012-01-01

    The purpose of this study was to experimentally assess the validity of heterogeneity-corrected dose-volume prescription on respiratory-averaged computed tomography (RACT) images in stereotactic body radiotherapy (SBRT) for moving tumors. Four-dimensional computed tomography (CT) data were acquired while a dynamic anthropomorphic thorax phantom with a solitary target moved. Motion pattern was based on cos (t) with a constant respiration period of 4.0 sec along the longitudinal axis of the CT couch. The extent of motion (A 1 ) was set in the range of 0.0–12.0 mm at 3.0-mm intervals. Treatment planning with the heterogeneity-corrected dose-volume prescription was designed on RACT images. A new commercially available Monte Carlo algorithm of well-commissioned 6-MV photon beam was used for dose calculation. Dosimetric effects of intrafractional tumor motion were then investigated experimentally under the same conditions as 4D CT simulation using the dynamic anthropomorphic thorax phantom, films, and an ionization chamber. The passing rate of γ index was 98.18%, with the criteria of 3 mm/3%. The dose error between the planned and the measured isocenter dose in moving condition was within ± 0.7%. From the dose area histograms on the film, the mean ± standard deviation of the dose covering 100% of the cross section of the target was 102.32 ± 1.20% (range, 100.59–103.49%). By contrast, the irradiated areas receiving more than 95% dose for A 1 = 12 mm were 1.46 and 1.33 times larger than those for A 1 = 0 mm in the coronal and sagittal planes, respectively. This phantom study demonstrated that the cross section of the target received 100% dose under moving conditions in both the coronal and sagittal planes, suggesting that the heterogeneity-corrected dose-volume prescription on RACT images is acceptable in SBRT for moving tumors.

  10. The validity of anthropometric leg muscle volume estimation across a wide spectrum: from able-bodied adults to individuals with a spinal cord injury.

    Science.gov (United States)

    Layec, Gwenael; Venturelli, Massimo; Jeong, Eun-Kee; Richardson, Russell S

    2014-05-01

    The assessment of muscle volume, and changes over time, have significant clinical and research-related implications. Methods to assess muscle volume vary from simple and inexpensive to complex and expensive. Therefore this study sought to examine the validity of muscle volume estimated simply by anthropometry compared with the more complex proton magnetic resonance imaging ((1)H-MRI) across a wide spectrum of individuals including those with a spinal cord injury (SCI), a group recognized to exhibit significant muscle atrophy. Accordingly, muscle volume of the thigh and lower leg of eight subjects with a SCI and eight able-bodied subjects (controls) was determined by anthropometry and (1)H-MRI. With either method, muscle volumes were significantly lower in the SCI compared with the controls (P muscle volume were strongly correlated to the values assessed by (1)H-MRI in both the thigh (r(2) = 0.89; P muscle volume compared with (1)H-MRI in both the thigh (mean bias = 2407cm(3)) and the lower (mean bias = 170 cm(3)) leg. Thus with an appropriate correction for this systemic overestimation, muscle volume estimated from anthropometric measurements is a valid approach and provides acceptable accuracy across a spectrum of adults with normal muscle mass to a SCI and severe muscle atrophy. In practical terms this study provides the formulas that add validity to the already simple and inexpensive anthropometric approach to assess muscle volume in clinical and research settings.

  11. Validation of multi-detector computed tomography as a non-invasive method for measuring ovarian volume in macaques (Macaca fascicularis).

    Science.gov (United States)

    Jones, Jeryl C; Appt, Susan E; Werre, Stephen R; Tan, Joshua C; Kaplan, Jay R

    2010-06-01

    The purpose of this study was to validate low radiation dose, contrast-enhanced, multi-detector computed tomography (MDCT) as a non-invasive method for measuring ovarian volume in macaques. Computed tomography scans of four known-volume phantoms and nine mature female cynomolgus macaques were acquired using a previously described, low radiation dose scanning protocol, intravenous contrast enhancement, and a 32-slice MDCT scanner. Immediately following MDCT, ovaries were surgically removed and the ovarian weights were measured. The ovarian volumes were determined using water displacement. A veterinary radiologist who was unaware of actual volumes measured ovarian CT volumes three times, using a laptop computer, pen display tablet, hand-traced regions of interest, and free image analysis software. A statistician selected and performed all tests comparing the actual and CT data. Ovaries were successfully located in all MDCT scans. The iliac arteries and veins, uterus, fallopian tubes, cervix, ureters, urinary bladder, rectum, and colon were also consistently visualized. Large antral follicles were detected in six ovaries. Phantom mean CT volume was 0.702+/-SD 0.504 cc and the mean actual volume was 0.743+/-SD 0.526 cc. Ovary mean CT volume was 0.258+/-SD 0.159 cc and mean water displacement volume was 0.257+/-SD 0.145 cc. For phantoms, the mean coefficient of variation for CT volumes was 2.5%. For ovaries, the least squares mean coefficient of variation for CT volumes was 5.4%. The ovarian CT volume was significantly associated with actual ovarian volume (ICC coefficient 0.79, regression coefficient 0.5, P=0.0006) and the actual ovarian weight (ICC coefficient 0.62, regression coefficient 0.6, P=0.015). There was no association between the CT volume accuracy and mean ovarian CT density (degree of intravenous contrast enhancement), and there was no proportional or fixed bias in the CT volume measurements. Findings from this study indicate that MDCT is a valid non

  12. Computer-generated display system guidelines. Volume 2. Developing an evaluation plan

    International Nuclear Information System (INIS)

    1984-09-01

    Volume 1 of this report provides guidance to utilities on the design of displays and the selection and retrofit of a computer-generated display system in the control room of an operating nuclear power plant. Volume 2 provides guidance on planning and managing empirical evaluation of computer-generated display systems, particularly when these displays are primary elements of computer-based operator aids. The guidance provided is in terms of a multilevel evaluation methodology that enables sequential consideration of three primary issues: (1) compatibility; (2) understandability; and (3) effectiveness. The evaluation process approaches these three issues with a top-down review of system objectives, functions, tasks, and information requirements. The process then moves bottom-up from lower-level to higher-level issues, employing different evaluation methods at each level in order to maximize the efficiency and effectiveness of the evaluation process

  13. Planning target volume (PTV) definition and its effects in the radiotherapy

    International Nuclear Information System (INIS)

    Poli, Maria Esmeralda Ramos

    2007-01-01

    Tills work intends to study the margins required to define a planning target volume (PTV) for adequate treatment of the mobile tumors such as prostate or those located in areas with less mobility as the ones in head and neck region, in the absence of daily localization imaging based. It is also intends to evaluate the impact caused by the PTV, in terms of dose, to the critical structures surrounding the PTV and its influence when inverse planning is used in the intensity-modulated radiation therapy (IMRT). Data from 387 prostate patients were analyzed retrospectively. Every patient in the study received daily pre-treatment localization with 2D ultrasound resulting in a total of 10,327 localizations, each comprising of an isocenter displacement in 3 directions: anterior-posterior (AP), right-left lateral (RL), and superior-inferior (SI). The mean displacement and standard deviation (SD) for each direction for each patient was computed from daily treatment records. The uncertainties (SD) in the target position were 4.4 mm (AP), 3.6 mm (RL), and 4.5 mm (SI). A study of the uncertainties in the daily positioning of 78 head and neck patients who used thermoplastic mask to immobilize them, evaluated with electronic portal imaging device (EPID), showed variations (SD) in the isocenter treatment position of 3.1 mm (AP), 1.5 mm (RL), and 4.5 mm (SI). By applying these shifts in an anthropomorphic phantom it was studied the dose-volume histograms resultant of the isocenter displacement in the daily treatment. The result showed the importance of putting margins in the clinical target volume to assure an adequate treatment and also showed that isocenter daily variation can cause an increase to the dose greater than the tolerance level to the critical organs. (author)

  14. Sampling based motion planning with reachable volumes: Application to manipulators and closed chain systems

    KAUST Repository

    McMahon, Troy

    2014-09-01

    © 2014 IEEE. Reachable volumes are a geometric representation of the regions the joints of a robot can reach. They can be used to generate constraint satisfying samples for problems including complicated linkage robots (e.g. closed chains and graspers). They can also be used to assist robot operators and to help in robot design.We show that reachable volumes have an O(1) complexity in unconstrained problems as well as in many constrained problems. We also show that reachable volumes can be computed in linear time and that reachable volume samples can be generated in linear time in problems without constraints. We experimentally validate reachable volume sampling, both with and without constraints on end effectors and/or internal joints. We show that reachable volume samples are less likely to be invalid due to self-collisions, making reachable volume sampling significantly more efficient for higher dimensional problems. We also show that these samples are easier to connect than others, resulting in better connected roadmaps. We demonstrate that our method can be applied to 262-dof, multi-loop, and tree-like linkages including combinations of planar, prismatic and spherical joints. In contrast, existing methods either cannot be used for these problems or do not produce good quality solutions.

  15. Sampling based motion planning with reachable volumes: Application to manipulators and closed chain systems

    KAUST Repository

    McMahon, Troy; Thomas, Shawna; Amato, Nancy M.

    2014-01-01

    © 2014 IEEE. Reachable volumes are a geometric representation of the regions the joints of a robot can reach. They can be used to generate constraint satisfying samples for problems including complicated linkage robots (e.g. closed chains and graspers). They can also be used to assist robot operators and to help in robot design.We show that reachable volumes have an O(1) complexity in unconstrained problems as well as in many constrained problems. We also show that reachable volumes can be computed in linear time and that reachable volume samples can be generated in linear time in problems without constraints. We experimentally validate reachable volume sampling, both with and without constraints on end effectors and/or internal joints. We show that reachable volume samples are less likely to be invalid due to self-collisions, making reachable volume sampling significantly more efficient for higher dimensional problems. We also show that these samples are easier to connect than others, resulting in better connected roadmaps. We demonstrate that our method can be applied to 262-dof, multi-loop, and tree-like linkages including combinations of planar, prismatic and spherical joints. In contrast, existing methods either cannot be used for these problems or do not produce good quality solutions.

  16. ICPP tank farm closure study. Volume III: Cost estimates, planning schedules, yearly cost flowcharts, and life-cycle cost estimates

    International Nuclear Information System (INIS)

    1998-02-01

    This volume contains information on cost estimates, planning schedules, yearly cost flowcharts, and life-cycle costs for the six options described in Volume 1, Section 2: Option 1 -- Total removal clean closure; No subsequent use; Option 2 -- Risk-based clean closure; LLW fill; Option 3 -- Risk-based clean closure; CERCLA fill; Option 4 -- Close to RCRA landfill standards; LLW fill; Option 5 -- Close to RCRA landfill standards; CERCLA fill; and Option 6 -- Close to RCRA landfill standards; Clean fill. This volume is divided into two portions. The first portion contains the cost and planning schedule estimates while the second portion contains life-cycle costs and yearly cash flow information for each option

  17. Fusion Engineering Device. Volume VI. Complementary development plan for engineering development

    International Nuclear Information System (INIS)

    1981-10-01

    The basic approach followed in this volume is to define key technical issues for several fusion reactor technologies and to device program strategies to resolve each of these issues. Particular attention has been paid to elucidating the role of FED vis-a-vis complementary (non-FED) facilities in this process. The remainder of this chapter consists of summaries of the major conclusions of the technology plans in each of the areas studied, i.e., plasma heating, magnetics, nuclear, and systems considerations

  18. Optimal grasp planning for a dexterous robotic hand using the volume of a generalized force ellipsoid during accepted flattening

    Directory of Open Access Journals (Sweden)

    Peng Jia

    2017-01-01

    Full Text Available A grasp planning method based on the volume and flattening of a generalized force ellipsoid is proposed to improve the grasping ability of a dexterous robotic hand. First, according to the general solution of joint torques for a dexterous robotic hand, a grasping indicator for the dexterous hand—the maximum volume of a generalized external force ellipsoid and the minimum volume of a generalized contact internal force ellipsoid during accepted flattening—is proposed. Second, an optimal grasp planning method based on a task is established using the grasping indicator as an objective function. Finally, a simulation analysis and grasping experiment are performed. Results show that when the grasping experiment is conducted with the grasping configuration and positions of contact points optimized using the proposed grasping indicator, the root-mean-square values of the joint torques and contact internal forces of the dexterous hand are at a minimum. The effectiveness of the proposed grasping planning method is thus demonstrated.

  19. Effectiveness of quantitative MAA SPECT/CT for the definition of vascularized hepatic volume and dosimetric approach: phantom validation and clinical preliminary results in patients with complex hepatic vascularization treated with yttrium-90-labeled microspheres.

    Science.gov (United States)

    Garin, Etienne; Lenoir, Laurence; Rolland, Yan; Laffont, Sophie; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Ardisson, Valérie; Bourguet, Patrick; Clement, Bruno; Boucher, Eveline

    2011-12-01

    The goal of this study was to assess the use of quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) analysis for vascularized volume measurements in the use of the yttrium-90-radiolabeled microspheres (TheraSphere). A phantom study was conducted for the validation of SPECT/CT volume measurement. SPECT/CT quantitative analysis was used for the measurement of the volume of distribution of the albumin macroaggregates (MAA; i.e., the vascularized volume) in the liver and the tumor, and the total activity contained in the liver and the tumor in four consecutive patients presenting with a complex liver vascularization referred for a treatment with TheraSphere. SPECT/CT volume measurement proved to be accurate (mean error <7%) and reproducible (interobserver concordance 0.99). For eight treatments, in cases of complex hepatic vascularization, the hepatic volumes based on angiography and CT led to a relative overestimation or underestimation of the vascularized hepatic volume by 43.2 ± 32.7% (5-87%) compared with SPECT/CT analyses. The vascularized liver volume taken into account calculated from SPECT/CT data, instead of angiography and CT data, results in modifying the activity injected for three treatments of eight. Moreover, quantitative analysis of SPECT/CT allows us to calculate the absorbed dose in the tumor and in the healthy liver, leading to doubling of the injected activity for one treatment of eight. MAA SPECT/CT is accurate for volume measurements. It provides a valuable contribution to the therapeutic planning of patients presenting with complex hepatic vascularization, in particular for calculating the vascularized liver volume, the activity to be injected and the absorbed doses. Studies should be conducted to assess the role of quantitative MAA/SPECT CT in therapeutic planning.

  20. Utility of Quantitative Tc-MAA SPECT/CT for yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach.

    Science.gov (United States)

    Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

    2011-01-01

    Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization.

  1. First impressions of 3D visual tools and dose volume histograms for plan evaluation

    International Nuclear Information System (INIS)

    Rattray, G.; Simitcioglu, A.; Parkinson, M.; Biggs, J.

    1999-01-01

    Converting from 2D to 3D treatment planning offers numerous challenges. The practices that have evolved in the 2D environment may not be applicable when translated into the 3D environment. One such practice is the methods used to evaluate a plan. In 2D planning a plane by plane comparison method is generally practiced. This type of evaluation method would not be appropriate for plans produced by a 3D planning system. To this end 3D dose displays and Dose Volume Histograms (DVHs) have been developed to facilitate the evaluation of such plans. A survey was conducted to determine the impressions of Radiation Therapists as they used these tools for the first time. The survey involved comparing a number of plans for a small group of patients and selecting the best plan for each patient. Three evaluation methods were assessed. These included the traditional plane by plane, 3D dose display, and DVHs. Those surveyed found the DVH to be the easiest of the three methods to use, with the 3D display being the next easiest. Copyright (1999) Blackwell Science Pty Ltd

  2. The dependence of prostate postimplant dosimetric quality on CT volume determination

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Butler, Wayne M.; Dorsey, Anthony T.; Lief, Jonathan H.

    1999-01-01

    the ultrasound volume approach. Despite the volume determinations being markedly different, no significant differences between the approaches were appreciated for V100, V150, V200, and D90. Large variations seen in D100 were uncorrelated to any of the other parameters and make D100 unsuitable as a quality indicator. Conclusions: In terms of a logarithmic measure, the variation between volumetric approach for V100, V150, V200, and D90 was less than one-fifth the variation of the CT volumes. These results which indicate relative independence of postimplant CT volume determination and dosimetric quality are only valid for a planning philosophy that includes the prostate with a periprostatic margin as the target volume

  3. Use of the SONET Score to Evaluate High Volume Emergency Department Overcrowding: A Prospective Derivation and Validation Study

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2015-01-01

    Full Text Available Background. The accuracy and utility of current Emergency Department (ED crowding estimation tools remain uncertain in EDs with high annual volumes. We aimed at deriving a more accurate tool to evaluate overcrowding in a high volume ED setting and determine the association between ED overcrowding and patient care outcomes. Methods. A novel scoring tool (SONET: Severely overcrowded-Overcrowded-Not overcrowded Estimation Tool was developed and validated in two EDs with both annual volumes exceeding 100,000. Patient care outcomes including the number of left without being seen (LWBS patients, average length of ED stay, ED 72-hour returns, and mortality were compared under the different crowding statuses. Results. The total number of ED patients, the number of mechanically ventilated patients, and patient acuity levels were independent risk factors affecting ED overcrowding. SONET was derived and found to better differentiate severely overcrowded, overcrowded, and not overcrowded statuses with similar results validated externally. In addition, SONET scores correlated with increased length of ED stay, number of LWBS patients, and ED 72-hour returns. Conclusions. SONET might be a better fit to determine high volume ED overcrowding. ED overcrowding negatively impacts patient care operations and often produces poor patient perceptions of standardized care delivery.

  4. WE-AB-209-05: Development of an Ultra-Fast High Quality Whole Breast Radiotherapy Treatment Planning System

    International Nuclear Information System (INIS)

    Sheng, Y; Li, T; Yoo, S; Yin, F; Blitzblau, R; Horton, J; Palta, M; Hahn, C; Wu, Q; Ge, Y

    2016-01-01

    Purpose: To enable near-real-time (<20sec) and interactive planning without compromising quality for whole breast RT treatment planning using tangential fields. Methods: Whole breast RT plans from 20 patients treated with single energy (SE, 6MV, 10 patients) or mixed energy (ME, 6/15MV, 10 patients) were randomly selected for model training. Additional 20 cases were used as validation cohort. The planning process for a new case consists of three fully automated steps:1. Energy Selection. A classification model automatically selects energy level. To build the energy selection model, principle component analysis (PCA) was applied to the digital reconstructed radiographs (DRRs) of training cases to extract anatomy-energy relationship.2. Fluence Estimation. Once energy is selected, a random forest (RF) model generates the initial fluence. This model summarizes the relationship between patient anatomy’s shape based features and the output fluence. 3. Fluence Fine-tuning. This step balances the overall dose contribution throughout the whole breast tissue by automatically selecting reference points and applying centrality correction. Fine-tuning works at beamlet-level until the dose distribution meets clinical objectives. Prior to finalization, physicians can also make patient-specific trade-offs between target coverage and high-dose volumes.The proposed method was validated by comparing auto-plans with manually generated clinical-plans using Wilcoxon Signed-Rank test. Results: In 19/20 cases the model suggested the same energy combination as clinical-plans. The target volume coverage V100% was 78.1±4.7% for auto-plans, and 79.3±4.8% for clinical-plans (p=0.12). Volumes receiving 105% Rx were 69.2±78.0cc for auto-plans compared to 83.9±87.2cc for clinical-plans (p=0.13). The mean V10Gy, V20Gy of the ipsilateral lung was 24.4±6.7%, 18.6±6.0% for auto plans and 24.6±6.7%, 18.9±6.1% for clinical-plans (p=0.04, <0.001). Total computational time for auto-plans was

  5. WE-AB-209-05: Development of an Ultra-Fast High Quality Whole Breast Radiotherapy Treatment Planning System

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Y [Duke University, Durham, NC (United States); Li, T [Thomas Jefferson University, Philadelphia, PA (United States); Yoo, S; Yin, F; Blitzblau, R; Horton, J; Palta, M; Hahn, C; Wu, Q [Duke University Medical Center, Durham, NC (United States); Ge, Y [University of North Carolina at Charlotte, Charlotte, NC (United States)

    2016-06-15

    Purpose: To enable near-real-time (<20sec) and interactive planning without compromising quality for whole breast RT treatment planning using tangential fields. Methods: Whole breast RT plans from 20 patients treated with single energy (SE, 6MV, 10 patients) or mixed energy (ME, 6/15MV, 10 patients) were randomly selected for model training. Additional 20 cases were used as validation cohort. The planning process for a new case consists of three fully automated steps:1. Energy Selection. A classification model automatically selects energy level. To build the energy selection model, principle component analysis (PCA) was applied to the digital reconstructed radiographs (DRRs) of training cases to extract anatomy-energy relationship.2. Fluence Estimation. Once energy is selected, a random forest (RF) model generates the initial fluence. This model summarizes the relationship between patient anatomy’s shape based features and the output fluence. 3. Fluence Fine-tuning. This step balances the overall dose contribution throughout the whole breast tissue by automatically selecting reference points and applying centrality correction. Fine-tuning works at beamlet-level until the dose distribution meets clinical objectives. Prior to finalization, physicians can also make patient-specific trade-offs between target coverage and high-dose volumes.The proposed method was validated by comparing auto-plans with manually generated clinical-plans using Wilcoxon Signed-Rank test. Results: In 19/20 cases the model suggested the same energy combination as clinical-plans. The target volume coverage V100% was 78.1±4.7% for auto-plans, and 79.3±4.8% for clinical-plans (p=0.12). Volumes receiving 105% Rx were 69.2±78.0cc for auto-plans compared to 83.9±87.2cc for clinical-plans (p=0.13). The mean V10Gy, V20Gy of the ipsilateral lung was 24.4±6.7%, 18.6±6.0% for auto plans and 24.6±6.7%, 18.9±6.1% for clinical-plans (p=0.04, <0.001). Total computational time for auto-plans was

  6. LLCEDATA and LLCECALC for Windows version 1.0, Volume 3: Software verification and validation

    International Nuclear Information System (INIS)

    McFadden, J.G.

    1998-01-01

    LLCEDATA and LLCECALC for Windows are user-friendly computer software programs that work together to determine the proper waste designation, handling, and disposition requirements for Long Length Contaminated Equipment (LLCE). LLCEDATA reads from a variety of data bases to produce an equipment data file(EDF) that represents a snapshot of both the LLCE and the tank from which it originates. LLCECALC reads the EDF and the gamma assay file (AV2) that is produced by the flexible Receiver Gamma Energy Analysis System. LLCECALC performs corrections to the AV2 file as it is being read and characterizes the LLCE. Both programs produce a variety of reports, including a characterization report and a status report. The status report documents each action taken by the user, LLCEDATA, and LLCECALC. Documentation for LLCEDATA and LLCECALC for Windows is available in three volumes. Volume 1 is a user's manual, which is intended as a quick reference for both LLCEDATA and LLCECALC. Volume 2 is a technical manual, which discusses system limitations and provides recommendations to the LLCE process. Volume 3 documents LLCEDATA and LLCECALC's verification and validation. Two of the three installation test cases, from Volume 1, are independently confirmed. Data bases used in LLCEDATA are verified and referenced. Both phases of LLCECALC process gamma and characterization, are extensively tested to verify that the methodology and algorithms used are correct

  7. Characterisation of radiotherapy planning volumes using textural analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nailon, William H.; Redpath, Anthony T.; McLaren, Duncan B. (Dept. of Oncology Physics, Edinburgh Cancer Centre, Western General Hospital, Edinburgh (United Kingdom))

    2008-08-15

    Computer-based artificial intelligence methods for classification and delineation of the gross tumour volume (GTV) on computerised tomography (CT) and magnetic resonance (MR) images do not, at present, provide the accuracy required for radiotherapy applications. This paper describes an image analysis method for classification of distinct regions within the GTV, and other clinically relevant regions, on CT images acquired on eight bladder cancer patients at the radiotherapy planning stage and thereafter at regular intervals during treatment. Statistical and fractal textural features (N=27) were calculated on the bladder, rectum and a control region identified on axial, coronal and sagittal CT images. Unsupervised classification results demonstrate that with a reduced feature set (N=3) the approach offers significant classification accuracy on axial, coronal and sagittal CT image planes and has the potential to be developed further for radiotherapy applications, particularly towards an automatic outlining approach

  8. Characterisation of radiotherapy planning volumes using textural analysis

    International Nuclear Information System (INIS)

    Nailon, William H.; Redpath, Anthony T.; McLaren, Duncan B.

    2008-01-01

    Computer-based artificial intelligence methods for classification and delineation of the gross tumour volume (GTV) on computerised tomography (CT) and magnetic resonance (MR) images do not, at present, provide the accuracy required for radiotherapy applications. This paper describes an image analysis method for classification of distinct regions within the GTV, and other clinically relevant regions, on CT images acquired on eight bladder cancer patients at the radiotherapy planning stage and thereafter at regular intervals during treatment. Statistical and fractal textural features (N=27) were calculated on the bladder, rectum and a control region identified on axial, coronal and sagittal CT images. Unsupervised classification results demonstrate that with a reduced feature set (N=3) the approach offers significant classification accuracy on axial, coronal and sagittal CT image planes and has the potential to be developed further for radiotherapy applications, particularly towards an automatic outlining approach

  9. Measuring the quality of Patients’ goals and action plans: development and validation of a novel tool

    Directory of Open Access Journals (Sweden)

    Teal Cayla R

    2012-12-01

    Full Text Available Abstract Background The purpose of this study is to develop and test reliability, validity, and utility of the Goal-Setting Evaluation Tool for Diabetes (GET-D. The effectiveness of diabetes self-management is predicated on goal-setting and action planning strategies. Evaluation of self-management interventions is hampered by the absence of tools to assess quality of goals and action plans. To address this gap, we developed the GET-D, a criteria-based, observer rating scale that measures the quality of patients’ diabetes goals and action plans. Methods We conducted 3-stage development of GET-D, including identification of criteria for observer ratings of goals and action plans, rater training and pilot testing; and then performed psychometric testing of the GET-D. Results Trained raters could effectively rate the quality of patient-generated goals and action plans using the GET-D. Ratings performed by trained evaluators demonstrated good raw agreement (94.4% and inter-rater reliability (Kappa = 0.66. Scores on the GET-D correlated well with measures theoretically associated with goal-setting, including patient activation (r=.252, P Conclusions The GET-D can reliably and validly rate the quality of goals and action plans. It holds promise as a measure of intervention fidelity for clinical interventions that promote diabetes self-management behaviors to improve clinical outcomes. Trial registration Clinicaltrials.gov Identifier: NCT00481286

  10. Evaluation of a commercial automatic treatment planning system for prostate cancers.

    Science.gov (United States)

    Nawa, Kanabu; Haga, Akihiro; Nomoto, Akihiro; Sarmiento, Raniel A; Shiraishi, Kenshiro; Yamashita, Hideomi; Nakagawa, Keiichi

    2017-01-01

    Recent developments in Radiation Oncology treatment planning have led to the development of software packages that facilitate automated intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) planning. Such solutions include site-specific modules, plan library methods, and algorithm-based methods. In this study, the plan quality for prostate cancer generated by the Auto-Planning module of the Pinnacle 3 radiation therapy treatment planning system (v9.10, Fitchburg, WI) is retrospectively evaluated. The Auto-Planning module of Pinnacle 3 uses a progressive optimization algorithm. Twenty-three prostate cancer cases, which had previously been planned and treated without lymph node irradiation, were replanned using the Auto-Planning module. Dose distributions were statistically compared with those of manual planning by the paired t-test at 5% significance level. Auto-Planning was performed without any manual intervention. Planning target volume (PTV) dose and dose to rectum were comparable between Auto-Planning and manual planning. The former, however, significantly reduced the dose to the bladder and femurs. Regression analysis was performed to examine the correlation between volume overlap between bladder and PTV divided by the total bladder volume and resultant V70. The findings showed that manual planning typically exhibits a logistic way for dose constraint, whereas Auto-Planning shows a more linear tendency. By calculating the Akaike information criterion (AIC) to validate the statistical model, a reduction of interoperator variation in Auto-Planning was shown. We showed that, for prostate cancer, the Auto-Planning module provided plans that are better than or comparable with those of manual planning. By comparing our results with those previously reported for head and neck cancer treatment, we recommend the homogeneous plan quality generated by the Auto-Planning module, which exhibits less dependence on anatomic complexity

  11. Fast in vivo volume dose reconstruction via reference dose perturbation

    International Nuclear Information System (INIS)

    Lu, Weiguo; Chen, Mingli; Mo, Xiaohu; Parnell, Donald; Olivera, Gustavo; Galmarini, Daniel

    2014-01-01

    Purpose: Accurate on-line reconstruction of in-vivo volume dose that accounts for both machine and patient discrepancy is not clinically available. We present a simple reference-dose-perturbation algorithm that reconstructs in-vivo volume dose fast and accurately. Methods: We modelled the volume dose as a function of the fluence map and density image. Machine (output variation, jaw/leaf position errors, etc.) and patient (setup error, weight loss, etc.) discrepancies between the plan and delivery were modelled as perturbation of the fluence map and density image, respectively. Delivered dose is modelled as perturbation of the reference dose due to change of the fluence map and density image. We used both simulated and clinical data to validate the algorithm. The planned dose was used as the reference. The reconstruction was perturbed from the reference and accounted for output-variations and the registered daily image. The reconstruction was compared with the ground truth via isodose lines and the Gamma Index. Results: For various plans and geometries, the volume doses were reconstructed in few seconds. The reconstruction generally matched well with the ground truth. For the 3%/3mm criteria, the Gamma pass rates were 98% for simulations and 95% for clinical data. The differences mainly appeared on the surface of the phantom/patient. Conclusions: A novel reference-dose-perturbation dose reconstruction model is presented. The model accounts for machine and patient discrepancy from planning. The algorithm is simple, fast, yet accurate, which makes online in-vivo 3D dose reconstruction clinically feasible.

  12. [Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering].

    Science.gov (United States)

    Günther, P; Tröger, J; Holland-Cunz, S; Waag, K L; Schenk, J P

    2006-08-01

    Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this.A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning.

  13. Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering

    International Nuclear Information System (INIS)

    Guenther, P.; Holland-Cunz, S.; Waag, K.L.

    2006-01-01

    Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [de

  14. Validation of low-volume enrichment protocols for detection of Escherichia coli O157 in raw ground beef components, using commercial kits.

    Science.gov (United States)

    Ahmed, Imtiaz; Hughes, Denise; Jenson, Ian; Karalis, Tass

    2009-03-01

    Testing of beef destined for use in ground beef products for the presence of Escherichia coli O157:H7 has become an important cornerstone of control and verification activities within many meat supply chains. Validation of the ability of methods to detect low levels of E. coli O157:H7 is critical to confidence in test systems. Many rapid methods have been validated against standard cultural methods for 25-g samples. In this study, a number of previously validated enrichment broths and commercially available test kits were validated for the detection of low numbers of E. coli O157:H7 in 375-g samples of raw ground beef component matrices using 1 liter of enrichment broth (large-sample:low-volume enrichment protocol). Standard AOAC International methods for 25-g samples in 225 ml of enrichment broth, using the same media, incubation conditions, and test kits, were used as reference methods. No significant differences were detected in the ability of any of the tests to detect low levels of E. coli O157:H7 in samples of raw ground beef components when enriched according to standard or large-sample:low-volume enrichment protocols. The use of large-sample:low-volume enrichment protocols provides cost savings for media and logistical benefits when handling and incubating large numbers of samples.

  15. RELAP-7 Software Verification and Validation Plan: Requirements Traceability Matrix (RTM) Part 1 – Physics and numerical methods

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Joon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yoo, Jun Soo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    This INL plan comprehensively describes the Requirements Traceability Matrix (RTM) on main physics and numerical method of the RELAP-7. The plan also describes the testing-based software verification and validation (SV&V) process—a set of specially designed software models used to test RELAP-7.

  16. Dosimetric validation of Monaco treatment planning system on an Elekta VersaHD linear accelerator.

    Science.gov (United States)

    Narayanasamy, Ganesh; Saenz, Daniel L; Defoor, Dewayne; Papanikolaou, Niko; Stathakis, Sotirios

    2017-11-01

    The purpose of this study is to perform dosimetric validation of Monaco treatment planning system version 5.1. The Elekta VersaHD linear accelerator with high dose rate flattening filter-free photon modes and electron energies was used in this study. The dosimetric output of the new Agility head combined with the FFF photon modes warranted this investigation into the dosimetric accuracy prior to clinical usage. A model of the VersaHD linac was created in Monaco TPS by Elekta using commissioned beam data including percent depth dose curves, beam profiles, and output factors. A variety of 3D conformal fields were created in Monaco TPS on a combined Plastic water/Styrofoam phantom and validated against measurements with a calibrated ion chamber. Some of the parameters varied including source to surface distance, field size, wedges, gantry angle, and depth for all photon and electron energies. In addition, a series of step and shoot IMRT, VMAT test plans, and patient plans on various anatomical sites were verified against measurements on a Delta 4 diode array. The agreement in point dose measurements was within 2% for all photon and electron energies in the homogeneous phantom and within 3% for photon energies in the heterogeneous phantom. The mean ± SD gamma passing rates of IMRT test fields yielded 93.8 ± 4.7% based on 2% dose difference and 2 mm distance-to-agreement criteria. Eight previously treated IMRT patient plans were replanned in Monaco TPS and five measurements on each yielded an average gamma passing rate of 95% with 6.7% confidence limit based on 3%, 3 mm gamma criteria. This investigation on dosimetric validation ensures accuracy of modeling VersaHD linac in Monaco TPS thereby improving patient safety. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  17. A treatment planning comparison of four target volume contouring guidelines for locally advanced pancreatic cancer radiotherapy

    International Nuclear Information System (INIS)

    Fokas, Emmanouil; Eccles, Cynthia; Patel, Neel; Chu, Kwun-Ye; Warren, Samantha; McKenna, W. Gillies; Brunner, Thomas B.

    2013-01-01

    Background and purpose: Contouring of target volumes varies significantly in radiotherapy of pancreatic ductal adenocarcinoma (PDAC). There is a lack of consensus as to whether elective lymph nodes (eLN’s) should be included or not in the planning target volume (PTV). In the present study we analyzed the dosimetric coverage of the eLN’s and organs at risk (OAR) by comparing four different contouring guidelines. Methods and materials: PTVs were delineated with (Oxford and RTOG guidelines) or without (Michigan and SCALOP guidelines) including the eLNs in eleven patients with PDAC. eLNs included the peripancreatic, paraaortic, paracaval, celiac trunk, superior mesenteric and portal vein clinical target volumes (CTVs). A 3D-CRT plan (50.40 Gy in 28 fractions) was performed to analyze and compare the dosimetric coverage of all eLNs and OAR between the 4 contouring guidelines. Results: The size of Oxford and RTOG PTVs was comparable and significantly larger than the SCALOP and Michigan PTVs. Interestingly the eLNs received a significant amount of incidental dose irradiation by PTV-based plans that only aimed to treat the tumor without the eLNs. The dosimetric coverage of eLN presented a large variability according to the respective contouring methods. The difference in the size of the 4 PTVs was reflected to the dose distribution at the OAR. Conclusions: Our study provides important information regarding the impact of different contouring guidelines on the dose distribution to the eLNs and the OAR in patients with locally advanced PDAC treated with radiotherapy

  18. Spatiotemporal radiotherapy planning using a global optimization approach

    Science.gov (United States)

    Adibi, Ali; Salari, Ehsan

    2018-02-01

    This paper aims at quantifying the extent of potential therapeutic gain, measured using biologically effective dose (BED), that can be achieved by altering the radiation dose distribution over treatment sessions in fractionated radiotherapy. To that end, a spatiotemporally integrated planning approach is developed, where the spatial and temporal dose modulations are optimized simultaneously. The concept of equivalent uniform BED (EUBED) is used to quantify and compare the clinical quality of spatiotemporally heterogeneous dose distributions in target and critical structures. This gives rise to a large-scale non-convex treatment-plan optimization problem, which is solved using global optimization techniques. The proposed spatiotemporal planning approach is tested on two stylized cancer cases resembling two different tumor sites and sensitivity analysis is performed for radio-biological and EUBED parameters. Numerical results validate that spatiotemporal plans are capable of delivering a larger BED to the target volume without increasing the BED in critical structures compared to conventional time-invariant plans. In particular, this additional gain is attributed to the irradiation of different regions of the target volume at different treatment sessions. Additionally, the trade-off between the potential therapeutic gain and the number of distinct dose distributions is quantified, which suggests a diminishing marginal gain as the number of dose distributions increases.

  19. Restricted Field IMRT Dramatically Enhances IMRT Planning for Mesothelioma

    International Nuclear Information System (INIS)

    Allen, Aaron M.; Schofield, Deborah; Hacker, Fred; Court, Laurence E.; Czerminska, Maria M.S.

    2007-01-01

    Purpose: To improve the target coverage and normal tissue sparing of intensity-modulated radiotherapy (IMRT) for mesothelioma after extrapleural pneumonectomy. Methods and Materials: Thirteen plans from patients previously treated with IMRT for mesothelioma were replanned using a restricted field technique. This technique was novel in two ways. It limited the entrance beams to 200 o around the target and three to four beams per case had their field apertures restricted down to the level of the heart or liver to further limit the contralateral lung dose. New constraints were added that included a mean lung dose of <9.5 Gy and volume receiving ≥5 Gy of <55%. Results: In all cases, the planning target volume coverage was excellent, with an average of 97% coverage of the planning target volume by the target dose. No change was seen in the target coverage with the new technique. The heart, kidneys, and esophagus were all kept under tolerance in all cases. The average mean lung dose, volume receiving ≥20 Gy, and volume receiving ≥5 Gy with the new technique was 6.6 Gy, 3.0%, and 50.8%, respectively, compared with 13.8 Gy, 15%, and 90% with the previous technique (p < 0.0001 for all three comparisons). The maximal value for any case in the cohort was 8.0 Gy, 7.3%, and 57.5% for the mean lung dose, volume receiving ≥20 Gy, and volume receiving ≥5 Gy, respectively. Conclusion: Restricted field IMRT provides an improved method to deliver IMRT to a complex target after extrapleural pneumonectomy. An upcoming Phase I trial will provide validation of these results

  20. Planning magnetic resonance imaging for prostate cancer intensity-modulated radiation therapy: Impact on target volumes, radiotherapy dose and androgen deprivation administration.

    Science.gov (United States)

    Horsley, Patrick J; Aherne, Noel J; Edwards, Grace V; Benjamin, Linus C; Wilcox, Shea W; McLachlan, Craig S; Assareh, Hassan; Welshman, Richard; McKay, Michael J; Shakespeare, Thomas P

    2015-03-01

    Magnetic resonance imaging (MRI) scans are increasingly utilized for radiotherapy planning to contour the primary tumors of patients undergoing intensity-modulated radiation therapy (IMRT). These scans may also demonstrate cancer extent and may affect the treatment plan. We assessed the impact of planning MRI detection of extracapsular extension, seminal vesicle invasion, or adjacent organ invasion on the staging, target volume delineation, doses, and hormonal therapy of patients with prostate cancer undergoing IMRT. The records of 509 consecutive patients with planning MRI scans being treated with IMRT for prostate cancer between January 2010 and July 2012 were retrospectively reviewed. Tumor staging and treatment plans before and after MRI were compared. Of the 509 patients, 103 (20%) were upstaged and 44 (9%) were migrated to a higher risk category as a result of findings at MRI. In 94 of 509 patients (18%), the MRI findings altered management. Ninety-four of 509 patients (18%) had a change to their clinical target volume (CTV) or treatment technique, and in 41 of 509 patients (8%) the duration of hormone therapy was changed because of MRI findings. The use of radiotherapy planning MRI altered CTV design, dose and/or duration of androgen deprivation in 18% of patients in this large, single institution series of men planned for dose-escalated prostate IMRT. This has substantial implications for radiotherapy target volumes and doses, as well as duration of androgen deprivation. Further research is required to investigate whether newer MRI techniques can simultaneously fulfill staging and radiotherapy contouring roles. © 2014 Wiley Publishing Asia Pty Ltd.

  1. Plan for studies of subsurface radionuclide migration at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory. Volume 1 of 2

    International Nuclear Information System (INIS)

    1983-11-01

    This document describes planned studies of subsurface radionuclide migration at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory. A plan is provided for each proposed study. The rational for arriving at the list of proposed studies is also presented. This document consists of two volumes. In the first volume, Sections 1 through 5 contain the introduction, the objectives of the proposed studies, and background information. The discussion is not comprehensive in detail; documents are referenced that discuss the background material in greater detail. Sections 6 through 9 identify and select the group of studies to be performed and discuss the peer review process. The second volume contains Appendices A and B, which present the assignment of responsibilities and the detailed plans, schedules, and costs for the proposed program

  2. NWTS waste package program plan. Volume II. Program logic networks

    International Nuclear Information System (INIS)

    1981-10-01

    This document describes the work planned for developing the technology to design, test and produce packages used for the long-term isolation of nuclear waste in deep geologic repositories. Waste forms considered include spent fuel and high-level waste. The testing and selection effort for barrier materials for radionuclide containment is described. The NWTS waste package program is a design-driven effort; waste package conceptual designs are used as input for preliminary designs, which are upgraded to a final design as materials and testing data become available. Performance assessment models are developed and validated. Milestones and a detailed schedule are given for the waste package development effort. Program logic networks defining work flow, interfaces among the NWTS Projects, and interrelationships of specific activities are presented. Detailed work elements are provided for the Waste Package Program Plan subtasks - design and development, waste form, barrier materials, and performance evaluation - for salt and basalt, host rocks for which the state of waste package knowledge and the corresponding data base are advanced

  3. Automated cerebellar segmentation: Validation and application to detect smaller volumes in children prenatally exposed to alcohol

    Directory of Open Access Journals (Sweden)

    Valerie A. Cardenas

    2014-01-01

    Discussion: These results demonstrate excellent reliability and validity of automated cerebellar volume and mid-sagittal area measurements, compared to manual measurements. These data also illustrate that this new technology for automatically delineating the cerebellum leads to conclusions regarding the effects of prenatal alcohol exposure on the cerebellum consistent with prior studies that used labor intensive manual delineation, even with a very small sample.

  4. Automated planning target volume generation: an evaluation pitting a computer-based tool against human experts

    International Nuclear Information System (INIS)

    Ketting, Case H.; Austin-Seymour, Mary; Kalet, Ira; Jacky, Jon; Kromhout-Schiro, Sharon; Hummel, Sharon; Unger, Jonathan; Fagan, Lawrence M.; Griffin, Tom

    1997-01-01

    Purpose: Software tools are seeing increased use in three-dimensional treatment planning. However, the development of these tools frequently omits careful evaluation before placing them in clinical use. This study demonstrates the application of a rigorous evaluation methodology using blinded peer review to an automated software tool that produces ICRU-50 planning target volumes (PTVs). Methods and Materials: Seven physicians from three different institutions involved in three-dimensional treatment planning participated in the evaluation. Four physicians drew partial PTVs on nine test cases, consisting of four nasopharynx and five lung primaries. Using the same information provided to the human experts, the computer tool generated PTVs for comparison. The remaining three physicians, designated evaluators, individually reviewed the PTVs for acceptability. To exclude bias, the evaluators were blinded to the source (human or computer) of the PTVs they reviewed. Their scorings of the PTVs were statistically examined to determine if the computer tool performed as well as the human experts. Results: The computer tool was as successful as the human experts in generating PTVs. Failures were primarily attributable to insufficient margins around the clinical target volume and to encroachment upon critical structures. In a qualitative analysis, the human and computer experts displayed similar types and distributions of errors. Conclusions: Rigorous evaluation of computer-based radiotherapy tools requires comparison to current practice and can reveal areas for improvement before the tool enters clinical practice

  5. Geostatistical approach for assessing soil volumes requiring remediation: validation using lead-polluted soils underlying a former smelting works.

    Science.gov (United States)

    Demougeot-Renard, Helene; De Fouquet, Chantal

    2004-10-01

    Assessing the volume of soil requiring remediation and the accuracy of this assessment constitutes an essential step in polluted site management. If this remediation volume is not properly assessed, misclassification may lead both to environmental risks (polluted soils may not be remediated) and financial risks (unexpected discovery of polluted soils may generate additional remediation costs). To minimize such risks, this paper proposes a geostatistical methodology based on stochastic simulations that allows the remediation volume and the uncertainty to be assessed using investigation data. The methodology thoroughly reproduces the conditions in which the soils are classified and extracted at the remediation stage. The validity of the approach is tested by applying it on the data collected during the investigation phase of a former lead smelting works and by comparing the results with the volume that has actually been remediated. This real remediated volume was composed of all the remediation units that were classified as polluted after systematic sampling and analysis during clean-up stage. The volume estimated from the 75 samples collected during site investigation slightly overestimates (5.3% relative error) the remediated volume deduced from 212 remediation units. Furthermore, the real volume falls within the range of uncertainty predicted using the proposed methodology.

  6. Automated IMRT planning with regional optimization using planning scripts.

    Science.gov (United States)

    Xhaferllari, Ilma; Wong, Eugene; Bzdusek, Karl; Lock, Michael; Chen, Jeff

    2013-01-07

    Intensity-modulated radiation therapy (IMRT) has become a standard technique in radiation therapy for treating different types of cancers. Various class solutions have been developed for simple cases (e.g., localized prostate, whole breast) to generate IMRT plans efficiently. However, for more complex cases (e.g., head and neck, pelvic nodes), it can be time-consuming for a planner to generate optimized IMRT plans. To generate optimal plans in these more complex cases which generally have multiple target volumes and organs at risk, it is often required to have additional IMRT optimization structures such as dose limiting ring structures, adjust beam geometry, select inverse planning objectives and associated weights, and additional IMRT objectives to reduce cold and hot spots in the dose distribution. These parameters are generally manually adjusted with a repeated trial and error approach during the optimization process. To improve IMRT planning efficiency in these more complex cases, an iterative method that incorporates some of these adjustment processes automatically in a planning script is designed, implemented, and validated. In particular, regional optimization has been implemented in an iterative way to reduce various hot or cold spots during the optimization process that begins with defining and automatic segmentation of hot and cold spots, introducing new objectives and their relative weights into inverse planning, and turn this into an iterative process with termination criteria. The method has been applied to three clinical sites: prostate with pelvic nodes, head and neck, and anal canal cancers, and has shown to reduce IMRT planning time significantly for clinical applications with improved plan quality. The IMRT planning scripts have been used for more than 500 clinical cases.

  7. Management response plan for the Chemical Safety Vulnerability Working Group report. Volume 2

    International Nuclear Information System (INIS)

    1994-09-01

    The Chemical Safety Vulnerability (CSV) Working Group was established to identify adverse conditions involving hazardous chemicals at DOE facilities that might result in fires or explosions, release of hazardous chemicals to the environment, or exposure of workers or the public to chemicals. A CSV Review was conducted in 146 facilities at 29 sites. Eight generic vulnerabilities were documented related to: abandoned chemicals and chemical residuals; past chemical spills and ground releases; characterization of legacy chemicals and wastes; disposition of legacy chemicals; storage facilities and conditions; condition of facilities and support systems; unanalyzed and unaddressed hazards; and inventory control and tracking. Weaknesses in five programmatic areas were also identified related to: management commitment and planning; chemical safety management programs; aging facilities that continue to operate; nonoperating facilities awaiting deactivation; and resource allocations. To address the facility-specific and site-specific vulnerabilities, responsible DOE and site-contractor line organizations have developed initial site response plans. These plans, presented as Volume 2 of this Management Response Plan, describe the actions needed to mitigate or eliminate the facility- and site-specific vulnerabilities identified by the CSV Working Group field verification teams. Initial site response plans are described for: Brookhaven National Lab., Hanford Site, Idaho National Engineering Lab., Lawrence Livermore National Lab., Los Alamos National Lab., Oak Ridge Reservation, Rocky Flats Plant, Sandia National Laboratories, and Savannah River Site

  8. Intensity-Modulated Radiotherapy for Craniospinal Irradiation: Target Volume Considerations, Dose Constraints, and Competing Risks

    International Nuclear Information System (INIS)

    Parker, William; Filion, Edith; Roberge, David; Freeman, Carolyn R.

    2007-01-01

    Purpose: To report the results of an analysis of dose received to tissues and organs outside the target volume, in the setting of spinal axis irradiation for the treatment of medulloblastoma, using three treatment techniques. Methods and Materials: Treatment plans (total dose, 23.4 Gy) for a standard two-dimensional (2D) technique, a three-dimensional (3D) technique using a 3D imaging-based target volume, and an intensity-modulated radiotherapy (IMRT) technique, were compared for 3 patients in terms of dose-volume statistics for target coverage, as well as organ at risk (OAR) and overall tissue sparing. Results: Planning target volume coverage and dose homogeneity was superior for the IMRT plans for V 95% (IMRT, 100%; 3D, 96%; 2D, 98%) and V 107% (IMRT, 3%; 3D, 38%; 2D, 37%). In terms of OAR sparing, the IMRT plan was better for all organs and whole-body contour when comparing V 10Gy , V 15Gy , and V 20Gy . The 3D plan was superior for V 5Gy and below. For the heart and liver in particular, the IMRT plans provided considerable sparing in terms of V 10Gy and above. In terms of the integral dose, the IMRT plans were superior for liver (IMRT, 21.9 J; 3D, 28.6 J; 2D, 38.6 J) and heart (IMRT, 9 J; 3D, 14.1J; 2D, 19.4 J), the 3D plan for the body contour (IMRT, 349 J; 3D, 337 J; 2D, 555 J). Conclusions: Intensity-modulated radiotherapy is a valid treatment option for spinal axis irradiation. We have shown that IMRT results in sparing of organs at risk without a significant increase in integral dose

  9. Validation of the Cumberland Energyplex concept. Volume 3. Appendixes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barkhordar, P.M.; Crooks, G.; Martin, P.J.

    1979-06-01

    This volume contains brief appendixes of three types: (1) some topics, although their analyses were not directly requested in the contract work statement, are examined because they are central to determining the validity of the Energyplex concept (e.g., socioeconomic effects and anaerobic digestion of animal wastes to recovery energy). (2) Methane from Illinois coal beds is discussed as a potential energy resource; however detailed analysis has been prevented by the paucity of necessary geological data. (3) Those Energyplex elements whose brief examination revealed some barrier are noted. For example, recovering energy from the relatively small amount of municipal waste generated by Charleston and Mattoon shows no economic promise, and cement production in the southeast quadrant of Illinois appears to be limited by inadequate quantities of limestone of the proper quality.

  10. Utilize target motion to cover clinical target volume (ctv) - a novel and practical treatment planning approach to manage respiratory motion

    International Nuclear Information System (INIS)

    Jin Jianyue; Ajlouni, Munther; Kong Fengming; Ryu, Samuel; Chetty, Indrin J.; Movsas, Benjamin

    2008-01-01

    Purpose: To use probability density function (PDF) to model motion effects and incorporate this information into treatment planning for lung cancers. Material and methods: PDFs were calculated from the respiratory motion traces of 10 patients. Motion effects were evaluated by convolving static dose distributions with various PDFs. Based on a differential dose prescription with relatively lower dose to the clinical target volume (CTV) than to the gross tumor volume (GTV), two approaches were proposed to incorporate PDFs into treatment planning. The first approach uses the GTV-based internal target volume (ITV) as the planning target volume (PTV) to ensure full dose to the GTV, and utilizes the motion-induced dose gradient to cover the CTV. The second approach employs an inhomogeneous static dose distribution within a minimized PTV to best match the prescription dose gradient. Results: Motion effects on dose distributions were minimal in the anterior-posterior (AP) and lateral directions: a 10-mm motion only induced about 3% of dose reduction in the peripheral target region. The motion effect was remarkable in the cranial-caudal direction. It varied with the motion amplitude, but tended to be similar for various respiratory patterns. For the first approach, a 10-15 mm motion would adequately cover the CTV (presumed to be 60-70% of the GTV dose) without employing the CTV in planning. For motions 15-mm. An example of inhomogeneous static dose distribution in a reduced PTV was given, and it showed significant dose reduction in the normal tissue without compromising target coverage. Conclusions: Respiratory motion-induced dose gradient can be utilized to cover the CTV and minimize the lung dose without the need for more sophisticated technologies

  11. Utility of Quantitative 99mTc-MAA SPECT/CT for 90yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach

    Science.gov (United States)

    Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

    2011-01-01

    Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization. PMID:21822489

  12. Plan for studies of subsurface radionuclide migration at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory. Volume 2 of 2. Appendices

    International Nuclear Information System (INIS)

    1983-11-01

    This document describes planned studies of subsurface radionuclide migration at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory. A plan is provided for each proposed study. The rational for arriving at the list of proposed studies is also presented. This document consists of two volumes. In the first volume, Sections 1 through 5 contain the introduction, the objectives of the proposed studies, and background information. The discussion is not comprehensive in detail; documents are referenced that discuss the background material in greater detail. Sections 6 through 9 identify and select the group of studies to be performed and discuss the peer review process. The second volume contains Appendices A and B, which present the assignment of responsibilities and the detailed plans, schedules, and costs for the proposed program

  13. Comparison of CT-based 3D treatment planning with simulator planning of pelvic irradiation of primary cervical carcinoma

    International Nuclear Information System (INIS)

    Knocke, T.H.; Pokrajac, B.; Fellner, C.; Poetter, R.

    1999-01-01

    In a prospective study on 20 subsequent patients with primary cervical carcinoma in Stages I to III simulator planning of a 4-field box-technique was performed. After defining the planning target volume (PTV) in the 3D planning system the field configuration of the simulator planning was transmitted. The resulting plan was compared to a second one based on the defined PTV and evaluated regarding a possible geographical miss and encompassment of the PTV by the treated volume (ICRU). Volumes of open and shaped portals were calculated for both techniques. Planning by simulation resulted in 1 geographical miss and in 10 more cases the encompassment of the PTV by the treated volume was inadequate. For a PTV of mean 1 729 cm 3 the mean volume defined by simulation was 3 120 cm 3 for the open portals and 2 702 cm 3 for the shaped portals. The volume reduction by blocks was 13,4% (mean). With CT-based 3D treatment planning the volume of the open portals was 3,3% (mean) enlarged to 3 224 cm 3 . The resulting mean volume of the shaped portals was 2 458 ccm. The reduction compared to the open portals was 23,8% (mean). The treated volumes were 244 cm 3 or 9% (mean) smaller compared to simulator planning. The 'treated volume/planning target volume ratio' was decreased from 1.59 to 1.42. (orig.) [de

  14. Precise Plan in the analysis of volume precision in SynergyTM conebeam CT image

    International Nuclear Information System (INIS)

    Bai Sen; Xu Qingfeng; Zhong Renming; Jiang Xiaoqin; Jiang Qingfeng; Xu Feng

    2007-01-01

    Objective: A method of checking the volume precision in Synergy TM conebeam CT image. Methods: To scan known phantoms (big, middle, small spheres, cubes and cuniform cavum) at different positions (CBCT centre and departure centre from 5, 8, 10 cm along the accelerator G-T way)with conebeam CT, the phantom volume of reconstructed images were measure. Then to compared measured volume of Synergy TM conebeam CT with fanbeam CT results and nominal values. Results: The middle spheres had 1.5% discrepancy in nominal values and metrical average values at CBCT centre and departure from centre 5, 8 cm along accelerator G-T way. The small spheres showed 8.1%, with 0.8 % of the big cube and 2.9% of small cube, in nominal values and metrical average values at CBCT centre and departure from centre 5, 8, 10 cm along the accelerator G-T way. Conclusion: In valid scan range of Synergy TM conebeam CT, reconstructed precision is independent of the distance deviation from the center. (authors)

  15. National Waste Terminal Storage Program: planning and control plan. Volume II. Plan description

    International Nuclear Information System (INIS)

    1977-05-01

    Objective of the NWTS program planning and control plan is to provide the information necessary for timely and effective OWI management decisions. Purpose is to describe the concepts and techniques that will be utilized by OWI to establish structured, completely planned and controlled technical, cost, and schedule NWTS baselines from which performance or progress can be accurately measured

  16. Roadway management plan based on rockfall modelling calibration and validation. Application along the Ma-10 road in Mallorca (Spain)

    Science.gov (United States)

    Mateos, Rosa Maria; Garcia, Inmaculada; Reichenbach, Paola; Herrera, Gerardo; Sarro, Roberto; Rius, Joan; Aguilo, Raul

    2016-04-01

    taking into account, not only the success, but also the mistakes. We have further validated the calibrated parameters along the Ma-road using the 63 rockfall recorded during the past 18 years along the road. 81.5% of the rockfalls are well represented by STONE modelling. Results have been exploited by the Road Maintenance Service of Mallorca for the design of the following road management plan: (1) Phase 1. Short-term. Design a specific plan for the road- sections where rockfalls were registered and modelling results were obtained. A large investment will be expended for implementation of retention and protection measures. (2) Phase 2. Medium-term. Design a specific plan for the road- sections where rockfalls were registered but no modelling results were obtained. For these cases, new studies at local scale are necessary as well as the application of other modelling software which include higher resolution input data. (3) Phase 3. Long-term. Design a specific plan for the road- sections where no rockfalls were registered but modelling results were obtained. These are potential rockfall areas and local and specific ground studies are necessaries. References Mateos RM (2006) Los movimientos de ladera en la Serra de Tramuntana (Mallorca). Caracterización geomecánica y análisis de peligrosidad. PhD. Servicio de Publicaciones de la Universidad Complutense de Madrid. Madrid, 299 p. Mateos RM, García-Moreno I, Herrera G, Mulas J (2013) Damage caused by recent mass-movements in Majorca (Spain), a region with a high risk due to tourism.Landslide Science and Practice.Claudio Margottini, Paolo Canuti and KyojiSassa (Editors). Volume 7: Social and Economic Impact and Policies. 105-113. Guzzetti F, Crosta G, Detti R, Agliardi F (2002) STONE: A computer program for the three-dimensional simulation of rock-falls. Computers Geosciences. Vol. 28:1079-1093.

  17. Experimental validation of the van Herk margin formula for lung radiation therapy

    International Nuclear Information System (INIS)

    Ecclestone, Gillian; Heath, Emily; Bissonnette, Jean-Pierre

    2013-01-01

    Purpose: To validate the van Herk margin formula for lung radiation therapy using realistic dose calculation algorithms and respiratory motion modeling. The robustness of the margin formula against variations in lesion size, peak-to-peak motion amplitude, tissue density, treatment technique, and plan conformity was assessed, along with the margin formula assumption of a homogeneous dose distribution with perfect plan conformity.Methods: 3DCRT and IMRT lung treatment plans were generated within the ORBIT treatment planning platform (RaySearch Laboratories, Sweden) on 4DCT datasets of virtual phantoms. Random and systematic respiratory motion induced errors were simulated using deformable registration and dose accumulation tools available within ORBIT for simulated cases of varying lesion sizes, peak-to-peak motion amplitudes, tissue densities, and plan conformities. A detailed comparison between the margin formula dose profile model, the planned dose profiles, and penumbra widths was also conducted to test the assumptions of the margin formula. Finally, a correction to account for imperfect plan conformity was tested as well as a novel application of the margin formula that accounts for the patient-specific motion trajectory.Results: The van Herk margin formula ensured full clinical target volume coverage for all 3DCRT and IMRT plans of all conformities with the exception of small lesions in soft tissue. No dosimetric trends with respect to plan technique or lesion size were observed for the systematic and random error simulations. However, accumulated plans showed that plan conformity decreased with increasing tumor motion amplitude. When comparing dose profiles assumed in the margin formula model to the treatment plans, discrepancies in the low dose regions were observed for the random and systematic error simulations. However, the margin formula respected, in all experiments, the 95% dose coverage required for planning target volume (PTV) margin derivation, as

  18. Effects of action planning and coping planning within the theory of planned behaviour

    DEFF Research Database (Denmark)

    Pakpour, Amir H.; Zedi, Isa mohammadi; Chatzisarantis, Nikos

    2011-01-01

    Objective: Patients on dialysis have low physical activity levels. The aim of the study was to examine the validity of action planning and coping planning within the theory of planned behaviour framework, for predicting physical activity behaviour of patients on hemodialysis. Methods: One hundred...... and forty four patients who were undergoing emodialysis were selected from dialysis centers. The mean age of the patients was 56.61 (SD= 11.38) years. The patients completed a questionnaire including variables from the theory of planned behaviour, action planning and coping planning. Physical activity...... was prospectively assessed at 4-weeks with the validated International Physical Activity Questionnaire self-report measure. A hierarchical regression analysis was performed to examine the effects of action planning and coping planning on physical activity behaviour. Results: There was a main effect for coping...

  19. Towards the elimination of Monte Carlo statistical fluctuation from dose volume histograms for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Sempau, J.; Bielajew, A.F.

    2000-01-01

    The Monte Carlo calculation of dose for radiotherapy treatment planning purposes introduces unavoidable statistical noise into the prediction of dose in a given volume element (voxel). When the doses in these voxels are summed to produce dose volume histograms (DVHs), this noise translates into a broadening of differential DVHs and correspondingly flatter DVHs. A brute force approach would entail calculating dose for long periods of time - enough to ensure that the DVHs had converged. In this paper we introduce an approach for deconvolving the statistical noise from DVHs, thereby obtaining estimates for converged DVHs obtained about 100 times faster than the brute force approach described above. There are two important implications of this work: (a) decisions based upon DVHs may be made much more economically using the new approach and (b) inverse treatment planning or optimization methods may employ Monte Carlo dose calculations at all stages of the iterative procedure since the prohibitive cost of Monte Carlo calculations at the intermediate calculation steps can be practically eliminated. (author)

  20. Physical validation issue of the NEPTUNE two-phase modelling: validation plan to be adopted, experimental programs to be set up and associated instrumentation techniques developed

    International Nuclear Information System (INIS)

    Pierre Peturaud; Eric Hervieu

    2005-01-01

    Full text of publication follows: A long-term joint development program for the next generation of nuclear reactors simulation tools has been launched in 2001 by EDF (Electricite de France) and CEA (Commissariat a l'Energie Atomique). The NEPTUNE Project constitutes the Thermal-Hydraulics part of this comprehensive program. Along with the underway development of this new two-phase flow software platform, the physical validation of the involved modelling is a crucial issue, whatever the modelling scale is, and the present paper deals with this issue. After a brief recall about the NEPTUNE platform, the general validation strategy to be adopted is first of all clarified by means of three major features: (i) physical validation in close connection with the concerned industrial applications, (ii) involving (as far as possible) a two-step process successively focusing on dominant separate models and assessing the whole modelling capability, (iii) thanks to the use of relevant data with respect to the validation aims. Based on this general validation process, a four-step generic work approach has been defined; it includes: (i) a thorough analysis of the concerned industrial applications to identify the key physical phenomena involved and associated dominant basic models, (ii) an assessment of these models against the available validation pieces of information, to specify the additional validation needs and define dedicated validation plans, (iii) an inventory and assessment of existing validation data (with respect to the requirements specified in the previous task) to identify the actual needs for new validation data, (iv) the specification of the new experimental programs to be set up to provide the needed new data. This work approach has been applied to the NEPTUNE software, focusing on 8 high priority industrial applications, and it has resulted in the definition of (i) the validation plan and experimental programs to be set up for the open medium 3D modelling

  1. Validity and reliability analysis of the planned behavior theory scale related to the testicular self-examination in a Turkish context.

    Science.gov (United States)

    Iyigun, Emine; Tastan, Sevinc; Ayhan, Hatice; Kose, Gulsah; Acikel, Cengizhan

    2016-06-01

    This study aimed to determine the validity and reliability levels of the Planned Behavior Theory Scale as related to a testicular self-examination. The study was carried out in a health-profession higher-education school in Ankara, Turkey, from April to June 2012. The study participants comprised 215 male students. Study data were collected by using a questionnaire, a planned behavior theory scale related to testicular self-examination, and Champion's Health Belief Model Scale (CHBMS). The sub-dimensions of the planned behavior theory scale, namely those of intention, attitude, subjective norms and self-efficacy, were found to have Cronbach's alpha values of between 0.81 and 0.89. Exploratory factor analysis showed that items of the scale had five factors that accounted for 75% of the variance. Of these, the sub-dimension of intention was found to have the highest level of contribution. A significant correlation was found between the sub-dimensions of the testicular self-examination planned behavior theory scale and those of CHBMS (p Planned Behavior Theory Scale is a valid and reliable measurement for Turkish society.

  2. ICPP calcined solids storage facility closure study. Volume II: Cost estimates, planning schedules, yearly cost flowcharts, and life-cycle cost estimates

    International Nuclear Information System (INIS)

    1998-02-01

    This document contains Volume II of the Closure Study for the Idaho Chemical Processing Plant Calcined Solids Storage Facility. This volume contains draft information on cost estimates, planning schedules, yearly cost flowcharts, and life-cycle costs for the four options described in Volume I: (1) Risk-Based Clean Closure; NRC Class C fill, (2) Risk-Based Clean Closure; Clean fill, (3) Closure to landfill Standards; NRC Class C fill, and (4) Closure to Landfill Standards; Clean fill

  3. ICPP calcined solids storage facility closure study. Volume II: Cost estimates, planning schedules, yearly cost flowcharts, and life-cycle cost estimates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    This document contains Volume II of the Closure Study for the Idaho Chemical Processing Plant Calcined Solids Storage Facility. This volume contains draft information on cost estimates, planning schedules, yearly cost flowcharts, and life-cycle costs for the four options described in Volume I: (1) Risk-Based Clean Closure; NRC Class C fill, (2) Risk-Based Clean Closure; Clean fill, (3) Closure to landfill Standards; NRC Class C fill, and (4) Closure to Landfill Standards; Clean fill.

  4. Intensity-modulated arc therapy with simultaneous integrated boost in the treatment of primary irresectable cervical cancer. Treatment planning, quality control, and clinical implementation

    Energy Technology Data Exchange (ETDEWEB)

    Vandecasteele, Katrien; De Neve, Wilfried; De Gersem, Werner; Paelinck, Leen; Fonteyne, Valerie; De Wagter, Carlos; De Meerleer, Gert [Dept. of Radiotherapy, Ghent Univ. Hospital (Belgium); Delrue, Louke; Villeirs, Geert [Dept. of Radiology, Ghent Univ. Hospital (Belgium); Makar, Amin [Dept. of Gynecology, Ghent Univ. Hospital (Belgium)

    2009-12-15

    Purpose: to report on the planning procedure, quality control, and clinical implementation of intensity-modulated arc therapy (IMAT) delivering a simultaneous integrated boost (SIB) in patients with primary irresectable cervix carcinoma. Patients and methods: six patients underwent PET-CT (positron emission tomography-computed tomography) and MRI (magnetic resonance imaging) before treatment planning. Prescription (25 fractions) was (1) a median dose (D{sub 50}) of 62, 58 and 56 Gy to the primary tumor (GTVcervix), primary clinical target volume (CTVcervix) and its planning target volume (PTVcervix), respectively; (2) a D{sub 50} of 60 Gy to the PET-positive lymph nodes (GTVnodes); (3) a minimal dose (D{sub 98}) of 45 Gy to the planning target volume of the elective lymph nodes (PTVnodes). IMAT plans were generated using an anatomy-based exclusion tool with the aid of weight and leaf position optimization. The dosimetric delivery of IMAT was validated preclinically using radiochromic film dosimetry. Results: five to nine arcs were needed to create valid IMAT plans. Dose constraints on D{sub 50} were not met in two patients (both GTVcervix: 1 Gy and 3 Gy less). D{sub 98} for PTVnodes was not met in three patients (1 Gy each). Film dosimetry showed excellent gamma evaluation. There were no treatment interruptions. Conclusion: IMAT allows delivering an SIB to the macroscopic tumor without compromising the dose to the elective lymph nodes or the organs at risk. The clinical implementation is feasible. (orig.)

  5. Comparison of CT based-CTV plan and CT based-ICRU38 plan in brachytherapy planning of uterine cervix cancer

    International Nuclear Information System (INIS)

    Shim, Jin Sup; Jo, Jung Kun; Si, Chang Keun; Lee, Ki Ho; Lee, Du Hyun; Choi, Kye Suk

    2004-01-01

    Although Improve of CT, MRI Radio-diagnosis and Radiation Therapy Planing, but we still use ICRU38 Planning system(2D film-based) broadly. 3-Dimensional ICR plan(CT image based) is not only offer tumor and normal tissue dose but also support DVH information. On this study, we plan irradiation-goal dose on CTV(CTV plan) and irradiation-goal dose on ICRU 38 point(ICRU38 plan) by use CT image. And compare with tumor-dose, rectal-dose, bladder-dose on both planning, and analysis DVH Sample 11 patients who treated by Ir-192 HDR. After 40 Gy external radiation therapy, ICR plan established. All the patients carry out CT-image scanned by CT-simulator. And we use PLATO(Nucletron) v.14.2 planing system. We draw CTV, rectum, bladder on the CT image. And establish plan irradiation- dose on CTV(CTV plan) and irradiation- dose on A-point(ICRU38 plan) CTV volume(average±SD) is 21.8±26.6 cm 3 , rectum volume(average±SD) is 60.9±25.0 cm 3 , bladder volume(average±SD) is 116.1±40.1cm 3 sampled 11 patients. The volume including 100% dose is 126.7±18.9 cm 3 on ICRU plan and 98.2±74.5 cm 3 on CTV plan. On ICRU planning, the other one's 22.0 cm 3 CTV volume who residual tumor size excess 4cm is not including 100% isodose. 8 patient's 12.9±5.9 cm 3 tumor volume who residual tumor size below 4 cm irradiated 100% dose. Bladder dose(recommended by ICRU 38) is 90.1±21.3 % on ICRU plan, 68.7±26.6% on CTV plan, and rectal dose is 86.4±18.3%, 76.9±15.6%. Bladder and Rectum maximum dose is 137.2±5.9%, 101.1±41.8% on ICRU plan, 107.6±47.9%, 86.9±30.8% on CTV plan. Therefore CTV plan more less normal issue-irradiated dose than ICRU plan. But one patient case who residual tumor size excess 4 cm, Normal tissue dose more higher than critical dose remarkably on CTV plan. 80% over-Irradiated rectal dose(V80rec) is 1.8±2.4 cm 3 on ICRU plan, 0.7±1.0 cm 3 on CTV plan. 80% over-Irradiated bladder dose(V80bla) is 12.2%±8.9 cm 3 on ICRU plan, 3.5±4.1 cm 3 on CTV plan. Likewise, CTV

  6. SU-F-T-150: Comparing Normal Tissue Irradiated Volumes for Proton Vs. Photon Treatment Plans On Lung Patients

    Energy Technology Data Exchange (ETDEWEB)

    Liu, A; Mohan, R; Liao, Z [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: The aim of this work is to compare the “irradiated volume” (IRV) of normal tissues receiving 5, 20, 50, 80 and 90% or higher of the prescription dose with passively scattered proton therapy (PSPT) vs. IMRT of lung cancer patients. The overall goal of this research is to understand the factors affecting outcomes of a randomized PSPT vs. IMRT lung trial. Methods: Thirteen lung cancer patients, selected randomly, were analyzed. Each patient had PSPT and IMRT 74 Gy (RBE) plans meeting the same normal tissue constraints generated. IRVs were created for pairs of IMRT and PSPT plans on each patient. The volume of iGTV, (respiratory motion-incorporated GTV) was subtracted from each IRV to create normal tissue irradiated volume IRVNT. The average of IRVNT DVHs over all patients was also calculated for both modalities and inter-compared as were the selected dose-volume indices. Probability (p value) curves were calculated based on the Wilcoxon matched-paired signed-rank test to determine the dose regions where the statistically significant differences existed. Results: As expected, the average 5, 20 and 50% IRVNT’s for PSPT was found to be significantly smaller than for IMRT (p < 0.001, 0.01, and 0.001 respectively). However, the average 90% IRVNT for PSPT was greater than for IMRT (p = 0.003) presumably due to larger penumbra of protons and the long range of protons in lower density media. The 80% IRVNT for PSPT was also larger but not statistically distinguishable (p = .224). Conclusion: PSPT modality has smaller irradiated volume at lower doses, but larger volume at high doses. A larger cohort of lung patients will be analyzed in the future and IRVNT of patients treated with PSPT and IMRT will be compared to determine if the irradiated volumes (the magnitude of “dose bath”) correlate with outcomes.

  7. Influence of increment of gantry angle and number of arcs on esophageal volumetric modulated arc therapy planning in Monaco planning system: A planning study

    Directory of Open Access Journals (Sweden)

    L Nithya

    2014-01-01

    Full Text Available The objective of this study was to analyze the influence of the increment of gantry angle and the number of arcs on esophageal volumetric modulated arc therapy plan. All plans were done in Monaco planning system for Elekta Synergy linear accelerator with 80 multileaf collimator (MLC. Volumetric modulated arc therapy (VMAT plans were done with different increment of gantry angle like 15 o , 20 o , 30 o and 40 o . The remaining parameters were similar for all the plans. The results were compared. To compare the plan quality with number of arcs, VMAT plans were done with single and dual arc with increment of gantry angle of 20 o . The dose to gross tumor volume (GTV for 60 Gy and planning target volume (PTV for 48 Gy was compared. The dosimetric parameters D 98% , D 95% , D 50% and D max of GTV were analyzed. The homogeneity index (HI and conformity index (CI of GTV were studied and the dose to 98% and 95% of PTV was analyzed. Maximum dose to spinal cord and planning risk volume of cord (PRV cord was compared. The Volume of lung receiving 10 Gy, 20 Gy and mean dose was analyzed. The volume of heart receiving 30 Gy and 45 Gy was compared. The volume of normal tissue receiving greater than 2 Gy and 5 Gy was compared. The number of monitor units (MU required to deliver the plans were compared. The plan with larger increment of gantry angle proved to be superior to smaller increment of gantry angle plans in terms of dose coverage, HI, CI and normal tissue sparing. The number of arcs did not make any difference in the quality of the plan.

  8. The Theory of Planned Behavior (TPB) and Pre-Service Teachers' Technology Acceptance: A Validation Study Using Structural Equation Modeling

    Science.gov (United States)

    Teo, Timothy; Tan, Lynde

    2012-01-01

    This study applies the theory of planned behavior (TPB), a theory that is commonly used in commercial settings, to the educational context to explain pre-service teachers' technology acceptance. It is also interested in examining its validity when used for this purpose. It has found evidence that the TPB is a valid model to explain pre-service…

  9. A generative model for segmentation of tumor and organs-at-risk for radiation therapy planning of glioblastoma patients

    DEFF Research Database (Denmark)

    Agn, Mikael; Law, Ian; Munck Af Rosenschöld, Per

    2016-01-01

    to model tumor shape. The method is not tuned to any specific imaging protocol and can simultaneously segment the gross tumor volume, peritumoral edema and healthy tissue structures relevant for radiotherapy planning. We validate the method on a manually delineated clinical data set of glioblastoma...

  10. Acute small bowel toxicity and preoperative chemoradiotherapy for rectal cancer: Investigating dose-volume relationships and role for inverse planning

    International Nuclear Information System (INIS)

    Tho, Lye Mun; Glegg, Martin; Paterson, Jennifer; Yap, Christina; MacLeod, Alice; McCabe, Marie; McDonald, Alexander C.

    2006-01-01

    Purpose: The relationship between volume of irradiated small bowel (VSB) and acute toxicity in rectal cancer radiotherapy is poorly quantified, particularly in patients receiving concurrent preoperative chemoradiotherapy. Using treatment planning data, we studied a series of such patients. Methods and Materials: Details of 41 patients with locally advanced rectal cancer were reviewed. All received 45 Gy in 25 fractions over 5 weeks, 3-4 fields three-dimensional conformal radiotherapy with daily 5-fluorouracil and folinic acid during Weeks 1 and 5. Toxicity was assessed prospectively in a weekly clinic. Using computed tomography planning software, the VSB was determined at 5 Gy dose intervals (V 5 , V 1 , etc.). Eight patients with maximal VSB had dosimetry and radiobiological modeling outcomes compared between inverse and conformal three-dimensional planning. Results: VSB correlated strongly with diarrheal severity at every dose level (p 5 and V 15 . Conclusions: A strong dose-volume relationship exists between VSB and acute diarrhea at all dose levels during preoperative chemoradiotherapy. Our constructed model may be useful in predicting toxicity, and this has been derived without the confounding influence of surgical excision on bowel function. Inverse planning can reduce calculated dose to small bowel and late NTCP, and its clinical role warrants further investigation

  11. An interactive tool for CT volume rendering and sagittal plane-picking of the prostate for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Jani, Ashesh B.; Pelizzari, Charles A.; Chen, George T.Y.; Grzezcszuk, Robert P.; Vijayakumar, Srinivasan

    1997-01-01

    Objective: Accurate and precise target volume and critical structure definition is a basic necessity in radiotherapy. The prostate, particularly the apex (an important potential site of recurrence in prostate cancer patients), is a challenging structure to define using any modality, including conventional axial CT. Invasive or expensive techniques, such as retrograde urethrography or MRI, could be avoided if localization of the prostate were possible using information already available on the planning CT. Our primary objective was to build a software tool to determine whether volume rendering and sagittal plane-picking, which are CT-based, noninvasive visualization techniques, were of utility in radiotherapy treatment planning for the prostate. Methods: Using AVS (Application Visualization System) on a Silicon Graphics Indigo 2 High Impact workstation, we have developed a tool that enables the clinician to efficiently navigate a CT volume and to use volume rendering and sagittal plane-picking to better define structures at any anatomic site. We applied the tool to the specific example of the prostate to compare the two visualization techniques with the current standard of axial CT. The prostate was defined on 80-slice CT scans (scanning thickness 4mm, pixel size 2mm x 2mm) of prostate cancer patients using axial CT images, volume-rendered CT images, and sagittal plane-picked images. Results: The navigation of the prostate using the different visualization techniques qualitatively demonstrated that the sagittal plane-picked images, and even more so the volume-rendered images, revealed the prostate (particularly the lower border) better in relationship to the surrounding regional anatomy (bladder, rectum, pelvis, and penile structures) than did the axial images. A quantitative comparison of the target volumes obtained by navigating using the different visualization techniques demonstrated that, when compared to the prostate volume defined on axial CT, a larger volume

  12. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    International Nuclear Information System (INIS)

    Hornblower, V D M; Yu, E; Fenster, A; Battista, J J; Malthaner, R A

    2007-01-01

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo

  13. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    Energy Technology Data Exchange (ETDEWEB)

    Hornblower, V D M [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Yu, E [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Fenster, A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Battista, J J [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Malthaner, R A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada)

    2007-01-07

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo.

  14. A novel four-dimensional radiotherapy planning strategy from a tumor-tracking beam's eye view

    Science.gov (United States)

    Li, Guang; Cohen, Patrice; Xie, Huchen; Low, Daniel; Li, Diana; Rimner, Andreas

    2012-11-01

    To investigate the feasibility of four-dimensional radiotherapy (4DRT) planning from a tumor-tracking beam's eye view (ttBEV) with reliable gross tumor volume (GTV) delineation, realistic normal tissue representation, high planning accuracy and low clinical workload, we propose and validate a novel 4D conformal planning strategy based on a synthesized 3.5D computed tomographic (3.5DCT) image with a motion-compensated tumor. To recreate patient anatomy from a ttBEV in the moving tumor coordinate system for 4DRT planning (or 4D planning), the centers of delineated GTVs in all phase CT images of 4DCT were aligned, and then the aligned CTs were averaged to produce a new 3.5DCT image. This GTV-motion-compensated CT contains a motionless target (with motion artifacts minimized) and motion-blurred normal tissues (with a realistic temporal density average). Semi-automatic threshold-based segmentation of the tumor, lung and body was applied, while manual delineation was used for other organs at risk (OARs). To validate this 3.5DCT-based 4D planning strategy, five patients with peripheral lung lesions of small size (tumor and a minor beam aperture and weighting adjustment to maintain plan conformality. The dose-volume histogram (DVH) of the 4DCT plan was created with two methods: one is an integrated DVH (iDVH4D), which is defined as the temporal average of all 3D-phase-plan DVHs, and the other (DVH4D) is based on the dose distribution in a reference phase CT image by dose warping from all phase plans using the displacement vector field (DVF) from a free-form deformable image registration (DIR). The DVH3.5D (for the 3.5DCT plan) was compared with both iDVH4D and DVH4D. To quantify the DVH difference between the 3.5DCT plan and the 4DCT plan, two methods were used: relative difference (%) of the areas underneath the DVH curves and the volumes receiving more than 20% (V20) and 50% (V50) of prescribed dose of these 4D plans. The volume of the delineated GTV from different phase

  15. Sequentially delivered boost plans are superior to simultaneously delivered plans in head and neck cancer when the boost volume is located further away from the parotid glands

    International Nuclear Information System (INIS)

    Lamers-Kuijper, Emmy; Heemsbergen, Wilma; Mourik, Anke van; Rasch, Coen

    2011-01-01

    Purpose: To find parameters that predict which head and neck patients benefit from a sequentially delivered boost treatment plan compared to a simultaneously delivered plan, with the aim to spare the salivary glands. Methods and materials: We evaluated 50 recently treated head and neck cancer patients. Apart from the clinical plan with a sequentially (SEQ) given boost using an Intensity Modulated Radiotherapy Technique (IMRT), a simultaneous integrated boost (SIB) technique plan was constructed with the same beam set-up. The mean dose to the parotid glands was calculated and compared. The elective nodal areas were bilateral in all cases, with a boost on either one side or both sides of the neck. Results: When the parotid gland volume and the Planning Target Volume (PTV) for the boost overlap there is on average a lower dose to the parotid gland with a SIB technique (-1.2 Gy), which is, however, not significant (p = 0.08). For all parotid glands with no boost PTV overlap, there is a benefit from a SEQ technique compared to a SIB technique for the gland evaluated (on average a 2.5 Gy lower dose to the parotid gland, p < 0.001). When the distance between gland and PTV is 0-1 cm, this difference is on average 0.8 Gy, for 1-2 cm distance 2.9 Gy and for glands with a distance greater than 2 cm, 3.3 Gy. When the lymph nodes on the evaluated side are also included in the boost PTV, however, this relationship between the distance and the gain of a SEQ seems less clear. Conclusions: A sequentially delivered boost technique results in a better treatment plan for most cases, compared to a simultaneous integrated boost IMRT technique, if the boost PTV is more than 1 cm away from at least one parotid gland.

  16. Methods for Reducing Normal Tissue Complication Probabilities in Oropharyngeal Cancer: Dose Reduction or Planning Target Volume Elimination

    Energy Technology Data Exchange (ETDEWEB)

    Samuels, Stuart E.; Eisbruch, Avraham; Vineberg, Karen; Lee, Jae; Lee, Choonik; Matuszak, Martha M.; Ten Haken, Randall K.; Brock, Kristy K., E-mail: kbrock@med.umich.edu

    2016-11-01

    Purpose: Strategies to reduce the toxicities of head and neck radiation (ie, dysphagia [difficulty swallowing] and xerostomia [dry mouth]) are currently underway. However, the predicted benefit of dose and planning target volume (PTV) reduction strategies is unknown. The purpose of the present study was to compare the normal tissue complication probabilities (NTCP) for swallowing and salivary structures in standard plans (70 Gy [P70]), dose-reduced plans (60 Gy [P60]), and plans eliminating the PTV margin. Methods and Materials: A total of 38 oropharyngeal cancer (OPC) plans were analyzed. Standard organ-sparing volumetric modulated arc therapy plans (P70) were created and then modified by eliminating the PTVs and treating the clinical tumor volumes (CTVs) only (C70) or maintaining the PTV but reducing the dose to 60 Gy (P60). NTCP dose models for the pharyngeal constrictors, glottis/supraglottic larynx, parotid glands (PGs), and submandibular glands (SMGs) were analyzed. The minimal clinically important benefit was defined as a mean change in NTCP of >5%. The P70 NTCP thresholds and overlap percentages of the organs at risk with the PTVs (56-59 Gy, vPTV{sub 56}) were evaluated to identify the predictors for NTCP improvement. Results: With the P60 plans, only the ipsilateral PG (iPG) benefited (23.9% vs 16.2%; P<.01). With the C70 plans, only the iPG (23.9% vs 17.5%; P<.01) and contralateral SMG (cSMG) (NTCP 32.1% vs 22.9%; P<.01) benefited. An iPG NTCP threshold of 20% and 30% predicted NTCP benefits for the P60 and C70 plans, respectively (P<.001). A cSMG NTCP threshold of 30% predicted for an NTCP benefit with the C70 plans (P<.001). Furthermore, for the iPG, a vPTV{sub 56} >13% predicted benefit with P60 (P<.001) and C70 (P=.002). For the cSMG, a vPTV{sub 56} >22% predicted benefit with C70 (P<.01). Conclusions: PTV elimination and dose-reduction lowered the NTCP of the iPG, and PTV elimination lowered the NTCP of the cSMG. NTCP thresholds and the

  17. Impact of 18-fluorodeoxyglucose positron emission tomography on computed tomography defined target volumes in radiation treatment planning of esophageal cancer : reduction in geographic misses with equal inter-observer variability

    NARCIS (Netherlands)

    Schreurs, Liesbeth; Busz, D. M.; Paardekooper, G. M. R. M.; Beukema, J. C.; Jager, P. L.; Van der Jagt, E. J.; van Dam, G. M.; Groen, H.; Plukker, J. Th. M.; Langendijk, J. A.

    P>Target volume definition in modern radiotherapy is based on planning computed tomography (CT). So far, 18-fluorodeoxyglucose positron emission tomography (FDG-PET) has not been included in planning modality in volume definition of esophageal cancer. This study evaluates fusion of FDG-PET and CT in

  18. SU-F-T-440: The Feasibility Research of Checking Cervical Cancer IMRT Pre- Treatment Dose Verification by Automated Treatment Planning Verification System

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X; Yin, Y; Lin, X [Shandong Cancer Hospital and Institute, China, Jinan, Shandong (China)

    2016-06-15

    Purpose: To assess the preliminary feasibility of automated treatment planning verification system in cervical cancer IMRT pre-treatment dose verification. Methods: The study selected randomly clinical IMRT treatment planning data for twenty patients with cervical cancer, all IMRT plans were divided into 7 fields to meet the dosimetric goals using a commercial treatment planning system(PianncleVersion 9.2and the EclipseVersion 13.5). The plans were exported to the Mobius 3D (M3D)server percentage differences of volume of a region of interest (ROI) and dose calculation of target region and organ at risk were evaluated, in order to validate the accuracy automated treatment planning verification system. Results: The difference of volume for Pinnacle to M3D was less than results for Eclipse to M3D in ROI, the biggest difference was 0.22± 0.69%, 3.5±1.89% for Pinnacle and Eclipse respectively. M3D showed slightly better agreement in dose of target and organ at risk compared with TPS. But after recalculating plans by M3D, dose difference for Pinnacle was less than Eclipse on average, results were within 3%. Conclusion: The method of utilizing the automated treatment planning system to validate the accuracy of plans is convenientbut the scope of differences still need more clinical patient cases to determine. At present, it should be used as a secondary check tool to improve safety in the clinical treatment planning.

  19. Standardization of prostate brachytherapy treatment plans

    International Nuclear Information System (INIS)

    Ove, Roger; Wallner, Kent; Badiozamani, Kas; Korjsseon, Tammy; Sutlief, Steven

    2001-01-01

    Purpose: Whereas custom-designed plans are the norm for prostate brachytherapy, the relationship between linear prostate dimensions and volume calls into question the routine need for customized treatment planning. With the goal of streamlining the treatment-planning process, we have compared the treatment margins (TMs) achieved with one standard plan applied to patients with a wide range of prostate volumes. Methods and Materials: Preimplant transrectal ultrasound (TRUS) images of 50 unselected University of Washington patients with T1-T2 cancer and a prostate volume between 20 cc and 50 cc were studied. Patients were arbitrarily grouped into categories of 20-30 cc, 30-40 cc, and 40-50 cc. A standard 19-needle plan was devised for patients in the 30- to 40-cc range, using an arbitrary minimum margin of 5 mm around the gross tumor volume (GTV), making use of inverse planning technology to achieve 100% coverage of the target volume with accentuation of dose at the periphery and sparing of the central region. The idealized plan was applied to each patient's TRUS study. The distances (TMs) between the prostatic edge (GTV) and treated volume (TV) were determined perpendicular to the prostatic margin. Results: Averaged over the entire patient group, the ratio of thickness to width was 1.4, whereas the ratio of length to width was 1.3. These values were fairly constant over the range of volumes, emphasizing that the prostate retains its general shape as volume increases. The idealized standard plan was overlaid on the ultrasound images of the 17 patients in the 30- to 40-cc group and the V100, the percentage of target volume receiving 100% or more of the prescription dose, was 98% or greater for 15 of the 17 patients. The lateral and posterior TMs fell within a narrow range, most being within 2 mm of the idealized 5-mm TM. To estimate whether a 10-cc volume-interval stratification was reasonable, the standard plan generated from the 30- to 40-cc prostate model was

  20. MO-FG-BRA-01: Development of An Image-Guided Dosimetric Planning System for Injectable Brachytherapy Using ELP Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Lafata, K [Duke University, Durham, North Carolina (United States); Duke University Medical Center, Durham, NC (United States); Schaal, J; Liu, W [Duke University, Durham, North Carolina (United States); Cai, J [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To develop, validate, and evaluate a methodology for determining dosimetry for intratumoral injections of elastin-like-polypeptide (ELP) brachytherapy nanoparticles. These organic-polymer-based nanoparticles are injectable, biodegradable, and genetically tunable. We present a genetically encoded polymer-solution, composed of novel radiolabeled-ELP nanoparticles that are custom-designed to self-assemble into a local source upon intratumoral injection. Our preliminary results of a small animal study demonstrate 100% tumor response, effective radionuclide retention-rates, strong in vivo stability, and no polymer-induced toxicities. While our approach is therefore highly promising for improved brachytherapy, the current workflow lacks a dosimetry framework. Methods: We are developing a robust software framework that provides image-guided dosimetric-planning capabilities for ELP brachytherapy. The user graphically places ELP injection sites within a µCT-planning-image, and independently defines each injection volume, concentration, and radioisotope to be used. The resulting internal dosimetry is then pre-determined by first modeling post-injection ELP advection-diffusion, and then calculating the resulting dose distribution based on a point- dose-kernel-convolution algorithm. We have experimentally measured ELP steady-state concentrations via µSPECT acquisition, and validated our dose calculation algorithm against Monte Carlo simulations of several radioactivity distributions. Finally, we have investigated potential advantages and limitations of various ELP injection parameters. Results: The µSPECT results demonstrated inhomogeneous steady-state distributions of ELP in tissue, and Monte Carlo radioactivity distributions were designed accordingly. Our algorithm yielded a root-mean-square-error of less than 2% for each distribution tested (average root-mean-square-error was 0.73%). Dose-Volume-Histogram analysis of five different plans showed how strategic

  1. IMRT plan validation

    International Nuclear Information System (INIS)

    Mijnheer, Ben

    2008-01-01

    The lecture encompassed the following topics: Utility of radiographic and radiochromic film dosimetry; Diode and chamber arrays; 3D gel dosimetry; 4D dosimetry; Experimental design for dosimetry; In vivo measurements. and Portal dosimetry. In conclusion, the following pitfalls, potential errors and possible actions are pointed to: (i) Lacking algorithm in the TPS for tongue-and-groove effect. Action: Design and verify a new plan in which the tongue-and-groove effect plays a minor role. Discuss the issue with the TPS manufacturer. (ii) Systematic deviations between TPS calculations and ionisation chamber measurements at the isocentre for plans with many small segments due to uncertainties in the output factor calculation. Action: Rescale the number of MUs. Discuss the issue with the TPS manufacturer. (iii) Large regions with gamma values larger than one during repeated film measurements, while ionisation chamber measurements are correct. Action: Check if the film batch is not expired and if so repeat the measurement with a new batch. (iv) Missing significant errors, e.g., resulting from MLC displacements, due to the limited resolution of the measuring device. Action: Move the device in different directions and repeat the measurement. (v) Missing errors at other parts of the PTV or in OARs by performing only one ionisation chamber measurement or an independent MU calculation at a point. Action: Perform also measurements in a plane for representative clinical cases. (vi) Wrong parameter in the TPS for the definition of leaf position. Action: Understand and verify the definition of leaf position in your TPS. (P.A.)

  2. The need for rotational margins in intensity-modulated radiotherapy and a new method for planning target volume design

    International Nuclear Information System (INIS)

    Langer, Mark Peter; Papiez, Lech; Spirydovich, Siarhei; Thai, Van

    2005-01-01

    Purpose: The effect of rotational errors on the coverage of clinical target volumes (CTVs) is examined. A new planning target volume (PTV) construction that considers the individual paths traced by movements of the target boundary points is developed. Methods and Materials: A standard uniform margin expansion was compared with a PTV constructed from the space swept out by a concave moving target. A new method formed the PTV by aggregating the separate convex hulls taken of the positions of the individual target boundary points in a sampling of CTV displacements. Results: A 0.5-cm uniform margin adequate for translations was inadequate given CTV rotation about a fixed off-center axis. A PTV formed of the target's swept-out area was 22% smaller than needed for coverage by a uniform margin, but computationally is not readily extended to translations combined with rotations about a shifting axis. Forming instead the union of convex hulls of the boundary points in a sampling of CTV displacements represented these movements in the PTV design and retained the target's concave shape. Conclusions: Planning target volumes should accommodate target rotation. The union of convex hulls of the boundary point positions in a sampling of displacements can effectively represent multiple sources of deviations while preserving target concavities

  3. Sampling-based motion planning with reachable volumes: Theoretical foundations

    KAUST Repository

    McMahon, Troy

    2014-05-01

    © 2014 IEEE. We introduce a new concept, reachable volumes, that denotes the set of points that the end effector of a chain or linkage can reach. We show that the reachable volume of a chain is equivalent to the Minkowski sum of the reachable volumes of its links, and give an efficient method for computing reachable volumes. We present a method for generating configurations using reachable volumes that is applicable to various types of robots including open and closed chain robots, tree-like robots, and complex robots including both loops and branches. We also describe how to apply constraints (both on end effectors and internal joints) using reachable volumes. Unlike previous methods, reachable volumes work for spherical and prismatic joints as well as planar joints. Visualizations of reachable volumes can allow an operator to see what positions the robot can reach and can guide robot design. We present visualizations of reachable volumes for representative robots including closed chains and graspers as well as for examples with joint and end effector constraints.

  4. Sampling-based motion planning with reachable volumes: Theoretical foundations

    KAUST Repository

    McMahon, Troy; Thomas, Shawna; Amato, Nancy M.

    2014-01-01

    © 2014 IEEE. We introduce a new concept, reachable volumes, that denotes the set of points that the end effector of a chain or linkage can reach. We show that the reachable volume of a chain is equivalent to the Minkowski sum of the reachable volumes of its links, and give an efficient method for computing reachable volumes. We present a method for generating configurations using reachable volumes that is applicable to various types of robots including open and closed chain robots, tree-like robots, and complex robots including both loops and branches. We also describe how to apply constraints (both on end effectors and internal joints) using reachable volumes. Unlike previous methods, reachable volumes work for spherical and prismatic joints as well as planar joints. Visualizations of reachable volumes can allow an operator to see what positions the robot can reach and can guide robot design. We present visualizations of reachable volumes for representative robots including closed chains and graspers as well as for examples with joint and end effector constraints.

  5. Normal tissue complication probabilities: dependence on choice of biological model and dose-volume histogram reduction scheme

    International Nuclear Information System (INIS)

    Moiseenko, Vitali; Battista, Jerry; Van Dyk, Jake

    2000-01-01

    Purpose: To evaluate the impact of dose-volume histogram (DVH) reduction schemes and models of normal tissue complication probability (NTCP) on ranking of radiation treatment plans. Methods and Materials: Data for liver complications in humans and for spinal cord in rats were used to derive input parameters of four different NTCP models. DVH reduction was performed using two schemes: 'effective volume' and 'preferred Lyman'. DVHs for competing treatment plans were derived from a sample DVH by varying dose uniformity in a high dose region so that the obtained cumulative DVHs intersected. Treatment plans were ranked according to the calculated NTCP values. Results: Whenever the preferred Lyman scheme was used to reduce the DVH, competing plans were indistinguishable as long as the mean dose was constant. The effective volume DVH reduction scheme did allow us to distinguish between these competing treatment plans. However, plan ranking depended on the radiobiological model used and its input parameters. Conclusions: Dose escalation will be a significant part of radiation treatment planning using new technologies, such as 3-D conformal radiotherapy and tomotherapy. Such dose escalation will depend on how the dose distributions in organs at risk are interpreted in terms of expected complication probabilities. The present study indicates considerable variability in predicted NTCP values because of the methods used for DVH reduction and radiobiological models and their input parameters. Animal studies and collection of standardized clinical data are needed to ascertain the effects of non-uniform dose distributions and to test the validity of the models currently in use

  6. Applications of NTCP calculations to treatment planning

    International Nuclear Information System (INIS)

    Kutcher, G.J.

    1995-01-01

    A fundamental step in the treatment decision process is the evaluation of a treatment plan. Most often treatment plans are judged by tradition using guidelines like target homogeneity and maximum dose to non-target tissues. While such judgments implicitly assume a relationship between dose distribution parameters and patient response, the judgment process is essentially supported by clinical outcomes from previous treatments. With the development of conformal therapy, new and unusual dose distributions and escalated doses are possible, while the clinical consequences are unknown. this situation has instigated attempts to place plan evaluation on a more systematic platform. One such endeavor has centered around attempts to calculate normal tissue complication probability (NTCP) and its sibling, tumor control probability (TCP). This lecture will be composed of two parts. The first will begin with a review of two categories of NTCP models: (1) an 'empirical' approach, based upon a power-law relationship between partial organ tolerance and irradiated volume, and histogram reduction to account for inhomogeneous irradiation: (2) a 'statistical' approach in which local responses are combined according to the underlying tissue architecture. Since both rely upon clinical data - often of limited and questionable validity - we will review some examples from the clinical and biological literature. The second part of the lecture will review clinical applications of biological-index based models: ranking competing treatment plans; design of dose escalation protocols; optimization of treatment plans with intensity modulation. We will also demonstrate how biological indices can be used to derive dose-volume histograms which account for treatment uncertainty

  7. Preliminary Validation of the Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Concept

    Science.gov (United States)

    Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine

    2004-01-01

    This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.

  8. Routine Radiological Environmental Monitoring Plan, Volume 2 Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel Nevada

    1998-12-31

    Supporting material for the plan includes: QUALITY ASSURANCE, ANALYSIS, AND SAMPLING PLAN FOR NTS AIR; QUALITY ASSURANCE, ANALYSIS, AND SAMPLING PLAN FOR WATER ON AND OFF THE NEVADA TEST SITE; QUALITY ASSURANCE, ANALYSIS, AND SAMPLING PLAN FOR NTS BIOTA; QUALITY ASSURANCE, ANALYSIS, AND SAMPLING PLAN FOR DIRECT RADIATION MONITORING; DATA QUALITY OBJECTIVES PROCESS; VADOSE ZONE MONITORING PLAN CHECKLIST.

  9. FY2017 Pilot Project Plan for the Nuclear Energy Knowledge and Validation Center Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Weiju [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-10-30

    validation data package (composed of experimental and dummy data) will provide a clear and complete instance delineating the structure of the desired validation data and enabling effective communication among the modeler, the experimentalist, and the knowledgebase developer. With a good common understanding of the desired data structure by the three parties of subject matter experts, further existing data hunting will be effectively conducted, new experimental data generation will be realistically pursued, knowledgebase schema will be practically designed; and code validation will be confidently planned.

  10. Impact of 18FDG-PET/CT on biological target volume (BTV) definition for treatment planning for non-small cell lung cancer patients

    International Nuclear Information System (INIS)

    Devic, Slobodan; Tomic, Nada; Faria, Sergio; Dean, Geoffrey; Lisbona, Robert; Parker, William; Kaufman, Chris; Podgorsak, Ervin B.

    2007-01-01

    This work represents our effort to test feasibility of FDG-based PET/CT on target volume delineation in radiotherapy treatment planning of NSCLC patients. Different methods have been developed to enable more precise target outlining using PET: Qualitative Visual Method, CTV=2.5 SUV units, linear SUV threshold function method, and CTV=40% Iso of Maximum Uptake Value. We are proposing reconstruction of three biological target volumes: necrotic BTV (same as PTV created by radiation oncologist using CT data), proliferating BTV (based on PET signal to background ratio 1:3) and hypoxic BTV (based on PET signal to background ratio of 1:19). Two IMRT plans were created and compared to the conventional treatment plan: 'conservative' IMRT plan delivers 52.5 Gy to the necrotic BTV and 65 Gy to the hypoxic BTV; 'radical' IMRT plan delivers 30 Gy to necrotic BTV, 52.5 Gy to proliferating BTV and 65 Gy to hypoxic BTV. Use of BTVs in IMRT plans is attractive because it increases dose to targets considered to need higher doses. It reduces considerably dose to heart and spinal cord, organs considered to limit dose escalation approaches in NSCLC treatment. 'Conservative' IMRT approach can be understood as a PET/CT-based concomitant boost to the tumor expressing the highest FDG uptake. 'Radical' plan implies deviation from the traditional uniform dose target coverage approach, with the intention of achieving better surrounding tissue sparing and ultimately allowing for dose escalation protocols relying on biologically based treatment planning

  11. An Analysis of Plan Robustness for Esophageal Tumors: Comparing Volumetric Modulated Arc Therapy Plans and Spot Scanning Proton Planning

    International Nuclear Information System (INIS)

    Warren, Samantha; Partridge, Mike; Bolsi, Alessandra; Lomax, Anthony J.; Hurt, Chris; Crosby, Thomas; Hawkins, Maria A.

    2016-01-01

    Purpose: Planning studies to compare x-ray and proton techniques and to select the most suitable technique for each patient have been hampered by the nonequivalence of several aspects of treatment planning and delivery. A fair comparison should compare similarly advanced delivery techniques from current clinical practice and also assess the robustness of each technique. The present study therefore compared volumetric modulated arc therapy (VMAT) and single-field optimization (SFO) spot scanning proton therapy plans created using a simultaneous integrated boost (SIB) for dose escalation in midesophageal cancer and analyzed the effect of setup and range uncertainties on these plans. Methods and Materials: For 21 patients, SIB plans with a physical dose prescription of 2 Gy or 2.5 Gy/fraction in 25 fractions to planning target volume (PTV)_5_0_G_y or PTV_6_2_._5_G_y (primary tumor with 0.5 cm margins) were created and evaluated for robustness to random setup errors and proton range errors. Dose–volume metrics were compared for the optimal and uncertainty plans, with P<.05 (Wilcoxon) considered significant. Results: SFO reduced the mean lung dose by 51.4% (range 35.1%-76.1%) and the mean heart dose by 40.9% (range 15.0%-57.4%) compared with VMAT. Proton plan robustness to a 3.5% range error was acceptable. For all patients, the clinical target volume D_9_8 was 95.0% to 100.4% of the prescribed dose and gross tumor volume (GTV) D_9_8 was 98.8% to 101%. Setup error robustness was patient anatomy dependent, and the potential minimum dose per fraction was always lower with SFO than with VMAT. The clinical target volume D_9_8 was lower by 0.6% to 7.8% of the prescribed dose, and the GTV D_9_8 was lower by 0.3% to 2.2% of the prescribed GTV dose. Conclusions: The SFO plans achieved significant sparing of normal tissue compared with the VMAT plans for midesophageal cancer. The target dose coverage in the SIB proton plans was less robust to random setup errors and might be

  12. An Analysis of Plan Robustness for Esophageal Tumors: Comparing Volumetric Modulated Arc Therapy Plans and Spot Scanning Proton Planning

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Samantha, E-mail: samantha.warren@oncology.ox.ac.uk [Cancer Research UK/Medical Research Council Oxford Institute for Radiation Oncology, Gray Laboratories, University of Oxford, Oxford (United Kingdom); Partridge, Mike [Cancer Research UK/Medical Research Council Oxford Institute for Radiation Oncology, Gray Laboratories, University of Oxford, Oxford (United Kingdom); Bolsi, Alessandra; Lomax, Anthony J. [Centre for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Hurt, Chris [Wales Cancer Trials Unit, School of Medicine, Heath Park, Cardiff (United Kingdom); Crosby, Thomas [Velindre Cancer Centre, Velindre Hospital, Cardiff (United Kingdom); Hawkins, Maria A. [Cancer Research UK/Medical Research Council Oxford Institute for Radiation Oncology, Gray Laboratories, University of Oxford, Oxford (United Kingdom)

    2016-05-01

    Purpose: Planning studies to compare x-ray and proton techniques and to select the most suitable technique for each patient have been hampered by the nonequivalence of several aspects of treatment planning and delivery. A fair comparison should compare similarly advanced delivery techniques from current clinical practice and also assess the robustness of each technique. The present study therefore compared volumetric modulated arc therapy (VMAT) and single-field optimization (SFO) spot scanning proton therapy plans created using a simultaneous integrated boost (SIB) for dose escalation in midesophageal cancer and analyzed the effect of setup and range uncertainties on these plans. Methods and Materials: For 21 patients, SIB plans with a physical dose prescription of 2 Gy or 2.5 Gy/fraction in 25 fractions to planning target volume (PTV){sub 50Gy} or PTV{sub 62.5Gy} (primary tumor with 0.5 cm margins) were created and evaluated for robustness to random setup errors and proton range errors. Dose–volume metrics were compared for the optimal and uncertainty plans, with P<.05 (Wilcoxon) considered significant. Results: SFO reduced the mean lung dose by 51.4% (range 35.1%-76.1%) and the mean heart dose by 40.9% (range 15.0%-57.4%) compared with VMAT. Proton plan robustness to a 3.5% range error was acceptable. For all patients, the clinical target volume D{sub 98} was 95.0% to 100.4% of the prescribed dose and gross tumor volume (GTV) D{sub 98} was 98.8% to 101%. Setup error robustness was patient anatomy dependent, and the potential minimum dose per fraction was always lower with SFO than with VMAT. The clinical target volume D{sub 98} was lower by 0.6% to 7.8% of the prescribed dose, and the GTV D{sub 98} was lower by 0.3% to 2.2% of the prescribed GTV dose. Conclusions: The SFO plans achieved significant sparing of normal tissue compared with the VMAT plans for midesophageal cancer. The target dose coverage in the SIB proton plans was less robust to random setup

  13. An Anatomically Validated Brachial Plexus Contouring Method for Intensity Modulated Radiation Therapy Planning

    International Nuclear Information System (INIS)

    Van de Velde, Joris; Audenaert, Emmanuel; Speleers, Bruno; Vercauteren, Tom; Mulliez, Thomas; Vandemaele, Pieter; Achten, Eric; Kerckaert, Ingrid; D'Herde, Katharina; De Neve, Wilfried; Van Hoof, Tom

    2013-01-01

    Purpose: To develop contouring guidelines for the brachial plexus (BP) using anatomically validated cadaver datasets. Magnetic resonance imaging (MRI) and computed tomography (CT) were used to obtain detailed visualizations of the BP region, with the goal of achieving maximal inclusion of the actual BP in a small contoured volume while also accommodating for anatomic variations. Methods and Materials: CT and MRI were obtained for 8 cadavers positioned for intensity modulated radiation therapy. 3-dimensional reconstructions of soft tissue (from MRI) and bone (from CT) were combined to create 8 separate enhanced CT project files. Dissection of the corresponding cadavers anatomically validated the reconstructions created. Seven enhanced CT project files were then automatically fitted, separately in different regions, to obtain a single dataset of superimposed BP regions that incorporated anatomic variations. From this dataset, improved BP contouring guidelines were developed. These guidelines were then applied to the 7 original CT project files and also to 1 additional file, left out from the superimposing procedure. The percentage of BP inclusion was compared with the published guidelines. Results: The anatomic validation procedure showed a high level of conformity for the BP regions examined between the 3-dimensional reconstructions generated and the dissected counterparts. Accurate and detailed BP contouring guidelines were developed, which provided corresponding guidance for each level in a clinical dataset. An average margin of 4.7 mm around the anatomically validated BP contour is sufficient to accommodate for anatomic variations. Using the new guidelines, 100% inclusion of the BP was achieved, compared with a mean inclusion of 37.75% when published guidelines were applied. Conclusion: Improved guidelines for BP delineation were developed using combined MRI and CT imaging with validation by anatomic dissection

  14. The application of positron emission tomography/computed tomography in radiation treatment planning: effect on gross target volume definition and treatment management.

    Science.gov (United States)

    Iğdem, S; Alço, G; Ercan, T; Unalan, B; Kara, B; Geceer, G; Akman, C; Zengin, F O; Atilla, S; Okkan, S

    2010-04-01

    To analyse the effect of the use of molecular imaging on gross target volume (GTV) definition and treatment management. Fifty patients with various solid tumours who underwent positron emission tomography (PET)/computed tomography (CT) simulation for radiotherapy planning from 2006 to 2008 were enrolled in this study. First, F-18 fluorodeoxyglucose (FDG)-PET and CT scans of the treatment site in the treatment position and then a whole body scan were carried out with a dedicated PET/CT scanner and fused thereafter. FDG-avid primary tumour and lymph nodes were included into the GTV. A multidisciplinary team defined the target volume, and contouring was carried out by a radiation oncologist using visual methods. To compare the PET/CT-based volumes with CT-based volumes, contours were drawn on CT-only data with the help of site-specific radiologists who were blind to the PET/CT results after a median time of 7 months. In general, our PET/CT volumes were larger than our CT-based volumes. This difference was significant in patients with head and neck cancers. Major changes (> or =25%) in GTV delineation were observed in 44% of patients. In 16% of cases, PET/CT detected incidental second primaries and metastatic disease, changing the treatment strategy from curative to palliative. Integrating functional imaging with FDG-PET/CT into the radiotherapy planning process resulted in major changes in a significant proportion of our patients. An interdisciplinary approach between imaging and radiation oncology departments is essential in defining the target volumes. Copyright 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  15. NWTS waste package program plan. Volume I. Program strategy, description, and schedule

    International Nuclear Information System (INIS)

    1981-10-01

    This document describes the work planned for developing the technology to design, test and produce packages used for the long-term isolation of nuclear waste in deep geologic repositories. Waste forms considered include spent fuel and high-level waste. The testing and selection effort for barrier materials for radionuclide containment is described. The NWTS waste package program is a design-driven effort; waste package conceptual designs are used as input for preliminary designs, which are upgraded to a final design as materials and testing data become available. Performance assessment models are developed and validated. Milestones and a detailed schedule are given for the waste package development effort. Program logic networks defining work flow, interfaces among the NWTS Projects, and interrelationships of specific activities are presented. Detailed work elements are provided for the Waste Package Program Plan subtasks - design and development, waste form, barrier materials, and performance evaluation - for salt and basalt, host rocks for which the state of waste package knowledge and the corresponding data base are advanced

  16. Validation and configuration management plan for the KE basins KE-PU spreadsheet code

    International Nuclear Information System (INIS)

    Harris, R.A.

    1996-01-01

    This report provides documentation of the spreadsheet KE-PU software that is used to verify compliance with the Operational Safety Requirement and Process Standard limit on the amount of plutonium in the KE-Basin sandfilter backwash pit. Included are: A summary of the verification of the method and technique used in KE-PU that were documented elsewhere, the requirements, plans, and results of validation tests that confirm the proper functioning of the software, the procedures and approvals required to make changes to the software, and the method used to maintain configuration control over the software

  17. Management of low-level radioactive waste in the Southeast Compact Region: Volume 2, Management plan: Final report

    International Nuclear Information System (INIS)

    1985-07-01

    The Southeast Compact Commission for Low-Level Radioactive Waste Management has begun the development of a regional low-level radioactive waste management plan. They have reviewed and analyzed existing data on current low-level radioactive waste volumes shipped for disposal by generators in the Southeast region and have supplemented existing data by direct contact with State regulatory personnel, disposal site operators, and individual generators. The Commission has also projected the amounts and types of waste expected to require offsite disposal. This characterized data base and the projections of waste volumes and types through 1996 are included in this volume. Alternative disposal and treatment technologies were evaluated for management of the waste in the region. This evaluation consisted of a review of the literature concerning the several technologies in low level radioactive waste management. This information is summarized in Appendix A. 72 refs., 28 figs., 30 tabs

  18. Evaluation of plan quality assurance models for prostate cancer patients based on fully automatically generated Pareto-optimal treatment plans.

    Science.gov (United States)

    Wang, Yibing; Breedveld, Sebastiaan; Heijmen, Ben; Petit, Steven F

    2016-06-07

    IMRT planning with commercial Treatment Planning Systems (TPSs) is a trial-and-error process. Consequently, the quality of treatment plans may not be consistent among patients, planners and institutions. Recently, different plan quality assurance (QA) models have been proposed, that could flag and guide improvement of suboptimal treatment plans. However, the performance of these models was validated using plans that were created using the conventional trail-and-error treatment planning process. Consequently, it is challenging to assess and compare quantitatively the accuracy of different treatment planning QA models. Therefore, we created a golden standard dataset of consistently planned Pareto-optimal IMRT plans for 115 prostate patients. Next, the dataset was used to assess the performance of a treatment planning QA model that uses the overlap volume histogram (OVH). 115 prostate IMRT plans were fully automatically planned using our in-house developed TPS Erasmus-iCycle. An existing OVH model was trained on the plans of 58 of the patients. Next it was applied to predict DVHs of the rectum, bladder and anus of the remaining 57 patients. The predictions were compared with the achieved values of the golden standard plans for the rectum D mean, V 65, and V 75, and D mean of the anus and the bladder. For the rectum, the prediction errors (predicted-achieved) were only  -0.2  ±  0.9 Gy (mean  ±  1 SD) for D mean,-1.0  ±  1.6% for V 65, and  -0.4  ±  1.1% for V 75. For D mean of the anus and the bladder, the prediction error was 0.1  ±  1.6 Gy and 4.8  ±  4.1 Gy, respectively. Increasing the training cohort to 114 patients only led to minor improvements. A dataset of consistently planned Pareto-optimal prostate IMRT plans was generated. This dataset can be used to train new, and validate and compare existing treatment planning QA models, and has been made publicly available. The OVH model was highly accurate

  19. Intercenter validation of a knowledge based model for automated planning of volumetric modulated arc therapy for prostate cancer. The experience of the German RapidPlan Consortium.

    Directory of Open Access Journals (Sweden)

    Carolin Schubert

    Full Text Available To evaluate the performance of a model-based optimisation process for volumetric modulated arc therapy applied to prostate cancer in a multicentric cooperative group. The RapidPlan (RP knowledge-based engine was tested for the planning of Volumetric modulated arc therapy with RapidArc on prostate cancer patients. The study was conducted in the frame of the German RapidPlan Consortium (GRC.43 patients from one institute of the GRC were used to build and train a RP model. This was further shared with all members of the GRC plus an external site from a different country to increase the heterogeneity of the patient's sampling. An in silico multicentric validation of the model was performed at planning level by comparing RP against reference plans optimized according to institutional procedures. A total of 60 patients from 7 institutes were used.On average, the automated RP based plans resulted fully consistent with the manually optimised set with a modest tendency to improvement in the medium-to-high dose region. A per-site stratification allowed to identify different patterns of performance of the model with some organs at risk resulting better spared with the manual or with the automated approach but in all cases the RP data fulfilled the clinical acceptability requirements. Discrepancies in the performance were due to different contouring protocols or to different emphasis put in the optimization of the manual cases.The multicentric validation demonstrated that it was possible to satisfactorily optimize with the knowledge based model patients from all participating centres. In the presence of possibly significant differences in the contouring protocols, the automated plans, though acceptable and fulfilling the benchmark goals, might benefit from further fine tuning of the constraints. The study demonstrates that, at least for the case of prostate cancer patients, it is possibile to share models among different clinical institutes in a cooperative

  20. Design and validation of a 3D virtual reality desktop system for sonographic length and volume measurements in early pregnancy evaluation.

    Science.gov (United States)

    Baken, Leonie; van Gruting, Isabelle M A; Steegers, Eric A P; van der Spek, Peter J; Exalto, Niek; Koning, Anton H J

    2015-03-01

    To design and validate a desktop virtual reality (VR) system, for presentation and assessment of volumetric data, based on commercially off-the-shelf hardware as an alternative to a fully immersive CAVE-like I-Space VR system. We designed a desktop VR system, using a three-dimensional (3D) monitor and a six degrees-of-freedom tracking system. A personal computer uses the V-Scope (Erasmus MC, Rotterdam, The Netherlands) volume-rendering application, developed for the I-Space, to create a hologram of volumetric data. Inter- and intraobserver reliability for crown-rump length and embryonic volume measurements are investigated using Bland-Altman plots and intraclass correlation coefficients. Time required for the measurements was recorded. Comparing the I-Space and the desktop VR system, the mean difference for crown-rump length is -0.34% (limits of agreement -2.58-1.89, ±2.24%) and for embryonic volume -0.92% (limits of agreement -6.97-5.13, ±6.05%). Intra- and interobserver intraclass correlation coefficients of the desktop VR system were all >0.99. Measurement times were longer on the desktop VR system compared with the I-Space, but the differences were not statistically significant. A user-friendly desktop VR system can be put together using commercially off-the-shelf hardware at an acceptable price. This system provides a valid and reliable method for embryonic length and volume measurements and can be used in clinical practice. © 2014 Wiley Periodicals, Inc.

  1. Explicit optimization of plan quality measures in intensity-modulated radiation therapy treatment planning.

    Science.gov (United States)

    Engberg, Lovisa; Forsgren, Anders; Eriksson, Kjell; Hårdemark, Björn

    2017-06-01

    To formulate convex planning objectives of treatment plan multicriteria optimization with explicit relationships to the dose-volume histogram (DVH) statistics used in plan quality evaluation. Conventional planning objectives are designed to minimize the violation of DVH statistics thresholds using penalty functions. Although successful in guiding the DVH curve towards these thresholds, conventional planning objectives offer limited control of the individual points on the DVH curve (doses-at-volume) used to evaluate plan quality. In this study, we abandon the usual penalty-function framework and propose planning objectives that more closely relate to DVH statistics. The proposed planning objectives are based on mean-tail-dose, resulting in convex optimization. We also demonstrate how to adapt a standard optimization method to the proposed formulation in order to obtain a substantial reduction in computational cost. We investigated the potential of the proposed planning objectives as tools for optimizing DVH statistics through juxtaposition with the conventional planning objectives on two patient cases. Sets of treatment plans with differently balanced planning objectives were generated using either the proposed or the conventional approach. Dominance in the sense of better distributed doses-at-volume was observed in plans optimized within the proposed framework. The initial computational study indicates that the DVH statistics are better optimized and more efficiently balanced using the proposed planning objectives than using the conventional approach. © 2017 American Association of Physicists in Medicine.

  2. A Broadly Adaptive Array of Dose-Constraint Templates for Planning of Intensity-Modulated Radiation Therapy for Advanced T-Stage Nasopharyngeal Carcinoma

    International Nuclear Information System (INIS)

    Chau, R.M.-C.; Leung, S.-F.; Kam, M.K.-M.; Cheung, K.-Y.; Kwan, W.-H.; Yu, K.-H.; Chiu, K.-W.; Cheung, M.L.-M.; Chan, A.T.-C.

    2009-01-01

    Purpose: To develop and validate adaptive dose-constraint templates in intensity-modulated radiotherapy (IMRT) planning for advanced T-stage nasopharyngeal carcinoma (NPC). Method and Materials: Dose-volume histograms of clinically approved plans for 20 patients with advanced T-stage NPC were analyzed, and the pattern of distribution in relation to the degree of overlap between targets and organs at risk (OARs) was explored. An adaptive dose constraint template (ADCT) was developed based on the degree of overlap. Another set of 10 patients with advanced T-stage NPC was selected for validation. Results of the manual arm optimization protocol and the ADCT optimization protocol were compared with respect to dose optimization time, conformity indices, multiple-dose end points, tumor control probability, and normal tissue complication probability. Results: For the ADCT protocol, average time required to achieve an acceptable plan was 9 minutes, with one optimization compared with 94 minutes with more than two optimizations of the manual arm protocol. Target coverage was similar between the manual arm and ADCT plans. A more desirable dose distribution in the region of overlap between planning target volume and OARs was achieved in the ADCT plan. Dose end points of OARs were similar between the manual arm and ADCT plans. Conclusions: With the developed ADCT, IMRT treatment planning becomes more efficient and less dependent on the planner's experience on dose optimization. The developed ADCT is applicable to a wide range of advanced T-stage NPC treatment and has the potential to be applied in a broader context to IMRT planning for other cancer sites

  3. Sci-Fri PM: Radiation Therapy, Planning, Imaging, and Special Techniques - 05: A novel respiratory motion simulation program for VMAT treatment plans: a phantom validation study

    Energy Technology Data Exchange (ETDEWEB)

    Hubley, Emily; Pierce, Greg; Ploquin, Nicolas [University of Calgary, Tom Baker Cancer Centre, Tom Baker Cancer Centre (Canada)

    2016-08-15

    Purpose: To develop and validate a computational method to simulate craniocaudal respiratory motion in a VMAT treatment plan. Methods: Three 4DCTs of the QUASAR respiratory motion phantom were acquired with a 2cm water-density spherical tumour embedded in cedar to simulate lung. The phantom was oscillating sinusoidally with an amplitude of 2cm and periods of 3, 4, and 5 seconds. An ITV was contoured and 5mm PTV margin was added. High and a low modulation factor VMAT plans were created for each scan. An in-house program was developed to simulate respiratory motion in the treatment plans by shifting the MLC leaf positions relative to the phantom. Each plan was delivered to the phantom and the dose was measured using Gafchromic film. The measured and calculated plans were compared using an absolute dose gamma analysis (3%/3mm). Results: The average gamma pass rate for the low modulation plan and high modulation plans were 91.1% and 51.4% respectively. The difference between the high and low modulation plans gamma pass rates is likely related to the different sampling frequency of the respiratory curve and the higher MLC leaf speeds in the high modulation plan. A high modulation plan has a slower gantry speed and therefore samples the breathing cycle at a coarser frequency leading to inaccuracies between the measured and planned doses. Conclusion: A simple program, including a novel method for increasing sampling frequency beyond the control point frequency, has been developed to simulate respiratory motion in VMAT plans by shifting the MLC leaf positions.

  4. Sci-Fri PM: Radiation Therapy, Planning, Imaging, and Special Techniques - 05: A novel respiratory motion simulation program for VMAT treatment plans: a phantom validation study

    International Nuclear Information System (INIS)

    Hubley, Emily; Pierce, Greg; Ploquin, Nicolas

    2016-01-01

    Purpose: To develop and validate a computational method to simulate craniocaudal respiratory motion in a VMAT treatment plan. Methods: Three 4DCTs of the QUASAR respiratory motion phantom were acquired with a 2cm water-density spherical tumour embedded in cedar to simulate lung. The phantom was oscillating sinusoidally with an amplitude of 2cm and periods of 3, 4, and 5 seconds. An ITV was contoured and 5mm PTV margin was added. High and a low modulation factor VMAT plans were created for each scan. An in-house program was developed to simulate respiratory motion in the treatment plans by shifting the MLC leaf positions relative to the phantom. Each plan was delivered to the phantom and the dose was measured using Gafchromic film. The measured and calculated plans were compared using an absolute dose gamma analysis (3%/3mm). Results: The average gamma pass rate for the low modulation plan and high modulation plans were 91.1% and 51.4% respectively. The difference between the high and low modulation plans gamma pass rates is likely related to the different sampling frequency of the respiratory curve and the higher MLC leaf speeds in the high modulation plan. A high modulation plan has a slower gantry speed and therefore samples the breathing cycle at a coarser frequency leading to inaccuracies between the measured and planned doses. Conclusion: A simple program, including a novel method for increasing sampling frequency beyond the control point frequency, has been developed to simulate respiratory motion in VMAT plans by shifting the MLC leaf positions.

  5. Hierarchical production planning for consumer goods

    NARCIS (Netherlands)

    Kok, de A.G.

    1990-01-01

    Abstract In this paper the mathematical logic behind a hierarchical planning procedure is discussed. The planning procedure is used to derive production volumes of consumer products. The essence of the planning procedure is that first a commitment is made concerning the production volume for a

  6. Sensitivity and uncertainty analyses applied to criticality safety validation, methods development. Volume 1

    International Nuclear Information System (INIS)

    Broadhead, B.L.; Hopper, C.M.; Childs, R.L.; Parks, C.V.

    1999-01-01

    This report presents the application of sensitivity and uncertainty (S/U) analysis methodologies to the code/data validation tasks of a criticality safety computational study. Sensitivity and uncertainty analysis methods were first developed for application to fast reactor studies in the 1970s. This work has revitalized and updated the available S/U computational capabilities such that they can be used as prototypic modules of the SCALE code system, which contains criticality analysis tools currently used by criticality safety practitioners. After complete development, simplified tools are expected to be released for general use. The S/U methods that are presented in this volume are designed to provide a formal means of establishing the range (or area) of applicability for criticality safety data validation studies. The development of parameters that are analogous to the standard trending parameters forms the key to the technique. These parameters are the D parameters, which represent the differences by group of sensitivity profiles, and the ck parameters, which are the correlation coefficients for the calculational uncertainties between systems; each set of parameters gives information relative to the similarity between pairs of selected systems, e.g., a critical experiment and a specific real-world system (the application)

  7. National Waste Terminal Storage Program: information management plan. Volume II. Plan description

    International Nuclear Information System (INIS)

    1977-05-01

    A comprehensive information management plan to provide for the systematic processing of large amounts of internally prepared and externally acquired documentation that will accrue to the Office of Waste Isolation (OWI) during the next decade is outlined. The Information Management Plan of the National Waste Terminal Storage (NWTS) Program is based on time proven procedures developed by government and industry for the requirements determination, acquisition, and the administration of documentation. The NWTS Information Management Plan is designed to establish the basis for the planning, development, implemenation, operation and maintenance of the NWTS Information Management System. This plan will help assure that documentation meets required quality standards and that each organization's needs are reflected when soliciting documentation from subcontractors. An example would be the Quality Assurance documentation requirement necessary to comply with eventual NRC licensing regulations. The provisions of the NWTS Information Management Plan will apply to all documentation from OWI contractors, subcontractors, and suppliers, and to OWI organizations for documentation prepared periodically for external dissemination

  8. The Unified Language Testing Plan: Speaking Proficiency Test. Spanish and English Pilot Validation Studies. Report Number 1.

    Science.gov (United States)

    Thornton, Julie A.

    This report describes one segment of the Federal Language Testing Board's Unified Language Testing Plan (ULTP), the validation of speaking proficiency tests in Spanish and English. The ULTP is a project to increase standardization of foreign language proficiency measurement and promote sharing of resources among testing programs in the federal…

  9. A validation of carbon fiber imaging couch top modeling in two radiation therapy treatment planning systems: Philips Pinnacle3 and BrainLAB iPlan RT Dose

    International Nuclear Information System (INIS)

    Njeh, Christopher F; Parker, Jason; Spurgin, Joseph; Rhoe, Elizabeth

    2012-01-01

    Carbon fiber (CF) is now the material of choice for radiation therapy couch tops. Initial designs included side metal bars for rigidity; however, with the advent of IGRT, involving on board imaging, new thicker CF couch tops without metal bars have been developed. The new design allows for excellent imaging at the expense of potentially unacceptable dose attenuation and perturbation. We set out to model the BrainLAB imaging couch top (ICT) in Philips Pinnacle 3 treatment planning system (TPS), to validate the already modeled ICT in BrainLAB iPlan RT Dose treatment planning system and to compute the magnitude of the loss in skin sparing. Using CF density of 0.55 g/cm 3 and foam density of 0.03 g/cm 3 , we demonstrated an excellent agreement between measured dose and Pinnacle 3 TPS computed dose using 6 MV beam. The agreement was within 1% for all gantry angle measured except for 120 o , which was 1.8%. The measured and iPlan RT Dose TPS computed dose agreed to within 1% for all gantry angles and field sizes measured except for 100 o where the agreement was 1.4% for 10 cm × 10 cm field size. Predicted attenuation through the couch by iPlan RT Dose TPS (3.4% - 9.5%) and Pinnacle 3 TPS (2% - 6.6%) were within the same magnitude and similar to previously reported in the literature. Pinnacle 3 TPS estimated an 8% to 20% increase in skin dose with increase in field size. With the introduction of the CF couch top, it estimated an increase in skin dose by approximately 46 - 90%. The clinical impact of omitting the couch in treatment planning will be dependent on the beam arrangement, the percentage of the beams intersecting the couch and their angles of incidence. We have successfully modeled the ICT in Pinnacle 3 TPS and validated the modeled ICT in iPlan RT Dose. It is recommended that the ICT be included in treatment planning for all treatments that involve posteriors beams. There is a significant increase in skin dose that is dependent on the percentage of the beam

  10. SU-G-TeP1-01: A Simulation Study to Investigate Maximum Allowable Deformations of Implant Geometry Before Plan Objectives Are Violated in Prostate HDR Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Babier, A [Department of Physics, Engineering Physics and Astronomy, Queens University, Kingston, Ontario (Canada); Joshi, C [Department of Physics, Engineering Physics and Astronomy, Queens University, Kingston, Ontario (Canada); Cancer Center of Southeastern Ontario, Kingston General Hospital, Kingston, Ontario (Canada)

    2016-06-15

    Purpose: In prostate HDR brachytherapy dose distributions are highly sensitive to changes in prostate volume and catheter displacements. We investigate the maximum deformations in implant geometry before planning objectives are violated. Methods: A typical prostate Ir-192 HDR brachytherapy reference plan was calculated on the Oncentra planning system, which used CT images from a tissue equivalent prostate phantom (CIRS Model 053S) embedded inside a pelvis wax phantom. The prostate was deformed and catheters were displaced in simulations using a code written in MATLAB. For each deformation dose distributions were calculated, based on TG43 methods, using the MATLAB code. The calculations were validated through comparison with Oncentra calculations for the reference plan, and agreed within 0.12%SD and 0.3%SD for dose and volume, respectively. Isotropic prostate volume deformations of up to +34% to −27% relative to its original volume, and longitudinal catheter displacements of 7.5 mm in superior and inferior directions were simulated. Planning objectives were based on American Brachytherapy Society guidelines for prostate and urethra volumes. A plan violated the planning objectives when less than 90% of the prostate volume received the prescribed dose or higher (V{sub 100}), or the urethral volume receiving 125% of prescribed dose or higher was more than 1 cc (U{sub 125}). Lastly, the dose homogeneity index (DHI=1-V{sub 150}/V{sub 100}) was evaluated; a plan was considered sub-optimal when the DHI fell below 0.62. Results and Conclusion: Planning objectives were violated when the prostate expanded by 10.7±0.5% or contracted by 11.0±0.2%; objectives were also violated when catheters were displaced by 4.15±0.15 mm and 3.70±0.15 mm in the superior and inferior directions, respectively. The DHI changes did not affect the plan optimality, except in the case of prostate compression. In general, catheter displacements have a significantly larger impact on plan

  11. Radiotherapy planning for glioblastoma based on a tumor growth model: improving target volume delineation

    Science.gov (United States)

    Unkelbach, Jan; Menze, Bjoern H.; Konukoglu, Ender; Dittmann, Florian; Le, Matthieu; Ayache, Nicholas; Shih, Helen A.

    2014-02-01

    Glioblastoma differ from many other tumors in the sense that they grow infiltratively into the brain tissue instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In current clinical practice, a uniform margin, typically two centimeters, is applied to account for microscopic spread of disease that is not directly assessable through imaging. The current treatment planning procedure can potentially be improved by accounting for the anisotropy of tumor growth, which arises from different factors: anatomical barriers such as the falx cerebri represent boundaries for migrating tumor cells. In addition, tumor cells primarily spread in white matter and infiltrate gray matter at lower rate. We investigate the use of a phenomenological tumor growth model for treatment planning. The model is based on the Fisher-Kolmogorov equation, which formalizes these growth characteristics and estimates the spatial distribution of tumor cells in normal appearing regions of the brain. The target volume for radiotherapy planning can be defined as an isoline of the simulated tumor cell density. This paper analyzes the model with respect to implications for target volume definition and identifies its most critical components. A retrospective study involving ten glioblastoma patients treated at our institution has been performed. To illustrate the main findings of the study, a detailed case study is presented for a glioblastoma located close to the falx. In this situation, the falx represents a boundary for migrating tumor cells, whereas the corpus callosum provides a route for the tumor to spread to the contralateral hemisphere. We further discuss the sensitivity of the model with respect to the input parameters. Correct segmentation of the brain appears to be the most

  12. Radiotherapy planning for glioblastoma based on a tumor growth model: improving target volume delineation

    International Nuclear Information System (INIS)

    Unkelbach, Jan; Dittmann, Florian; Le, Matthieu; Shih, Helen A; Menze, Bjoern H; Ayache, Nicholas; Konukoglu, Ender

    2014-01-01

    Glioblastoma differ from many other tumors in the sense that they grow infiltratively into the brain tissue instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In current clinical practice, a uniform margin, typically two centimeters, is applied to account for microscopic spread of disease that is not directly assessable through imaging. The current treatment planning procedure can potentially be improved by accounting for the anisotropy of tumor growth, which arises from different factors: anatomical barriers such as the falx cerebri represent boundaries for migrating tumor cells. In addition, tumor cells primarily spread in white matter and infiltrate gray matter at lower rate. We investigate the use of a phenomenological tumor growth model for treatment planning. The model is based on the Fisher–Kolmogorov equation, which formalizes these growth characteristics and estimates the spatial distribution of tumor cells in normal appearing regions of the brain. The target volume for radiotherapy planning can be defined as an isoline of the simulated tumor cell density. This paper analyzes the model with respect to implications for target volume definition and identifies its most critical components. A retrospective study involving ten glioblastoma patients treated at our institution has been performed. To illustrate the main findings of the study, a detailed case study is presented for a glioblastoma located close to the falx. In this situation, the falx represents a boundary for migrating tumor cells, whereas the corpus callosum provides a route for the tumor to spread to the contralateral hemisphere. We further discuss the sensitivity of the model with respect to the input parameters. Correct segmentation of the brain appears to be the most

  13. [Target volume margins for lung cancer: internal target volume/clinical target volume].

    Science.gov (United States)

    Jouin, A; Pourel, N

    2013-10-01

    The aim of this study was to carry out a review of margins that should be used for the delineation of target volumes in lung cancer, with a focus on margins from gross tumour volume (GTV) to clinical target volume (CTV) and internal target volume (ITV) delineation. Our review was based on a PubMed literature search with, as a cornerstone, the 2010 European Organisation for Research and Treatment of Cancer (EORTC) recommandations by De Ruysscher et al. The keywords used for the search were: radiotherapy, lung cancer, clinical target volume, internal target volume. The relevant information was categorized under the following headings: gross tumour volume definition (GTV), CTV-GTV margin (first tumoural CTV then nodal CTV definition), in field versus elective nodal irradiation, metabolic imaging role through the input of the PET scanner for tumour target volume and limitations of PET-CT imaging for nodal target volume definition, postoperative radiotherapy target volume definition, delineation of target volumes after induction chemotherapy; then the internal target volume is specified as well as tumoural mobility for lung cancer and respiratory gating techniques. Finally, a chapter is dedicated to planning target volume definition and another to small cell lung cancer. For each heading, the most relevant and recent clinical trials and publications are mentioned. Copyright © 2013. Published by Elsevier SAS.

  14. Nr 257 - Opinion presented on the behalf of the Commission of sustainable development and land planning on the finance bill for 2013 (nr 235), Volumes 1-10, ecology, sustainable development and planning, regional policies, research and higher education

    International Nuclear Information System (INIS)

    Krabal, Jacques; Sermier, Jean-Marie; Gaillard, Genevieve; Baupin, Denis; Pauvros, Remi; Benisti, Jacques Alain; Fromantin, Jean-Christophe; Calmette, Alain; Plisson, Philippe; Ginesy, Charles-Ange

    2012-01-01

    This huge document comprises ten volumes which present and discuss public programs (objectives, strategies, plans, and actions), public finances, economic activity data and evolutions, debates by commissions, and amendments on different issues. A first set of issues deals with ecology, sustainable development and planning: protection of the environment and risk prevention (volume 1), and then with sustainable development policies (vol. 2), landscapes, water, biodiversity, and geographic and cartographic information (vol. 3), ecological transition (vol. 4), road, railway and water transports (vol. 5), air transports (vol. 6), maritime affairs (vol. 7). The next volume addresses regional policies (vol. 8). The last parts concern research and higher education: research in the field of sustainable development (vol. 9) and in the fields of environments and resources (vol. 10)

  15. Prospective Validation of a High Dimensional Shape Model for Organ Motion in Intact Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, Casey W.; Green, Garrett; Noticewala, Sonal S.; Li, Nan; Shen, Hanjie [Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California (United States); Vaida, Florin [Division of Biostatistics and Bioinformatics, Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, California (United States); Mell, Loren K., E-mail: lmell@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California (United States)

    2016-11-15

    Purpose: Validated models are needed to justify strategies to define planning target volumes (PTVs) for intact cervical cancer used in clinical practice. Our objective was to independently validate a previously published shape model, using data collected prospectively from clinical trials. Methods and Materials: We analyzed 42 patients with intact cervical cancer treated with daily fractionated pelvic intensity modulated radiation therapy and concurrent chemotherapy in one of 2 prospective clinical trials. We collected online cone beam computed tomography (CBCT) scans before each fraction. Clinical target volume (CTV) structures from the planning computed tomography scan were cast onto each CBCT scan after rigid registration and manually redrawn to account for organ motion and deformation. We applied the 95% isodose cloud from the planning computed tomography scan to each CBCT scan and computed any CTV outside the 95% isodose cloud. The primary aim was to determine the proportion of CTVs that were encompassed within the 95% isodose volume. A 1-sample t test was used to test the hypothesis that the probability of complete coverage was different from 95%. We used mixed-effects logistic regression to assess effects of time and patient variability. Results: The 95% isodose line completely encompassed 92.3% of all CTVs (95% confidence interval, 88.3%-96.4%), not significantly different from the 95% probability anticipated a priori (P=.19). The overall proportion of missed CTVs was small: the grand mean of covered CTVs was 99.9%, and 95.2% of misses were located in the anterior body of the uterus. Time did not affect coverage probability (P=.71). Conclusions: With the clinical implementation of a previously proposed PTV definition strategy based on a shape model for intact cervical cancer, the probability of CTV coverage was high and the volume of CTV missed was low. This PTV expansion strategy is acceptable for clinical trials and practice; however, we recommend daily

  16. Risk factors for radiation pneumonitis after stereotactic radiation therapy for lung tumours: clinical usefulness of the planning target volume to total lung volume ratio.

    Science.gov (United States)

    Ueyama, Tomoko; Arimura, Takeshi; Takumi, Koji; Nakamura, Fumihiko; Higashi, Ryutaro; Ito, Soichiro; Fukukura, Yoshihiko; Umanodan, Tomokazu; Nakajo, Masanori; Koriyama, Chihaya; Yoshiura, Takashi

    2018-06-01

    To identify risk factors for symptomatic radiation pneumonitis (RP) after stereotactic radiation therapy (SRT) for lung tumours. We retrospectively evaluated 68 lung tumours in 63 patients treated with SRT between 2011 and 2015. RP was graded according to the National Cancer Institute-Common Terminology Criteria for Adverse Events version 4.0. SRT was delivered at 7.0-12.0 Gy per each fraction, once daily, to a total of 48-64 Gy (median, 50 Gy). Univariate analysis was performed to assess patient- and treatment-related factors, including age, sex, smoking index (SI), pulmonary function, tumour location, serum Krebs von den Lungen-6 value (KL-6), dose-volume metrics (V5, V10, V20, V30, V40 and VS5), homogeneity index of the planning target volume (PTV), PTV dose, mean lung dose (MLD), contralateral MLD and V2, PTV volume, lung volume and the PTV/lung volume ratio (PTV/Lung). Performance of PTV/Lung in predicting symptomatic RP was also analysed using receiver operating characteristic (ROC) analysis. The median follow-up period was 21 months. 10 of 63 patients (15.9%) developed symptomatic RP after SRT. On univariate analysis, V10, V20, PTV volume and PTV/Lung were significantly associated with occurrence of RP  ≥Grade 2. ROC curves indicated that symptomatic RP could be predicted using PTV/Lung [area under curve (AUC): 0.88, confidence interval (CI: 0.78-0.95), cut-off value: 1.09, sensitivity: 90.0% and specificity: 72.4%]. PTV/Lung is a good predictor of symptomatic RP after SRT. Advances in knowledge: The cases with high PTV/Lung should be carefully monitored with caution for the occurrence of RP after SRT.

  17. Using Micro-Synchrophasor Data for Advanced Distribution Grid Planning and Operations Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Emma [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McParland, Charles [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Roberts, Ciaran [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-07-01

    This report reviews the potential for distribution-grid phase-angle data that will be available from new micro-synchrophasors (µPMUs) to be utilized in existing distribution-grid planning and operations analysis. This data could augment the current diagnostic capabilities of grid analysis software, used in both planning and operations for applications such as fault location, and provide data for more accurate modeling of the distribution system. µPMUs are new distribution-grid sensors that will advance measurement and diagnostic capabilities and provide improved visibility of the distribution grid, enabling analysis of the grid’s increasingly complex loads that include features such as large volumes of distributed generation. Large volumes of DG leads to concerns on continued reliable operation of the grid, due to changing power flow characteristics and active generation, with its own protection and control capabilities. Using µPMU data on change in voltage phase angle between two points in conjunction with new and existing distribution-grid planning and operational tools is expected to enable model validation, state estimation, fault location, and renewable resource/load characterization. Our findings include: data measurement is outstripping the processing capabilities of planning and operational tools; not every tool can visualize a voltage phase-angle measurement to the degree of accuracy measured by advanced sensors, and the degree of accuracy in measurement required for the distribution grid is not defined; solving methods cannot handle the high volumes of data generated by modern sensors, so new models and solving methods (such as graph trace analysis) are needed; standardization of sensor-data communications platforms in planning and applications tools would allow integration of different vendors’ sensors and advanced measurement devices. In addition, data from advanced sources such as µPMUs could be used to validate models to improve

  18. TU-D-201-05: Validation of Treatment Planning Dose Calculations: Experience Working with MPPG 5.a

    Energy Technology Data Exchange (ETDEWEB)

    Xue, J; Park, J; Kim, L; Wang, C [MD Anderson Cancer Center at Cooper, Camden, NJ (United States); Balter, P; Ohrt, J; Kirsner, S; Ibbott, G [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: Newly published medical physics practice guideline (MPPG 5.a.) has set the minimum requirements for commissioning and QA of treatment planning dose calculations. We present our experience in the validation of a commercial treatment planning system based on MPPG 5.a. Methods: In addition to tests traditionally performed to commission a model-based dose calculation algorithm, extensive tests were carried out at short and extended SSDs, various depths, oblique gantry angles and off-axis conditions to verify the robustness and limitations of a dose calculation algorithm. A comparison between measured and calculated dose was performed based on validation tests and evaluation criteria recommended by MPPG 5.a. An ion chamber was used for the measurement of dose at points of interest, and diodes were used for photon IMRT/VMAT validations. Dose profiles were measured with a three-dimensional scanning system and calculated in the TPS using a virtual water phantom. Results: Calculated and measured absolute dose profiles were compared at each specified SSD and depth for open fields. The disagreement is easily identifiable with the difference curve. Subtle discrepancy has revealed the limitation of the measurement, e.g., a spike at the high dose region and an asymmetrical penumbra observed on the tests with an oblique MLC beam. The excellent results we had (> 98% pass rate on 3%/3mm gamma index) on the end-to-end tests for both IMRT and VMAT are attributed to the quality beam data and the good understanding of the modeling. The limitation of the model and the uncertainty of measurement were considered when comparing the results. Conclusion: The extensive tests recommended by the MPPG encourage us to understand the accuracy and limitations of a dose algorithm as well as the uncertainty of measurement. Our experience has shown how the suggested tests can be performed effectively to validate dose calculation models.

  19. Comparison of CT based-CTV plan and CT based-ICRU38 plan in brachytherapy planning of uterine cervix cancer

    International Nuclear Information System (INIS)

    Cho, Jung Keun; Han, Tae Jong

    2007-01-01

    Purpose : In spite of recent remarkable improvement of diagnostic imaging modalities such as CT, MRI, and PET and radiation therapy planing systems, ICR plan of uterine cervix cancer, based on recommendation of ICRU38(2D film-based) such as point A, is still used widely. A 3-dimensional ICR plan based on CT image provides Dose-Volume Histogram(DVH) information of the tumor and normal tissue. In this study, we compared tumor-dose, rectal-dose and bladder-dose through an analysis of DVH between CTV plan and ICRU38 plan based on CT image. Method and Material : We analyzed 11 patients with a cervix cancer who received the ICR of Ir-192 HDR. After 40Gy of external beam radiation therapy, ICR plan was established using PLATO(Nucletron) v.14.2 planning system. CT scan was done to all the patients using CT-simulator(Ultra Z, Philips). We contoured CTV, rectum and bladder on the CT image and established CTV plan which delivers the 100% dose to CTV and ICRU plan which delivers the 100% dose to the point A. Result : The volume(average±SD) of CTV, rectum and bladder in all of 11 patients is 21.8±6.6cm 3 , 60.9±25.0cm 3 , 111.6±40.1cm 3 respectively. The volume covered by 100% isodose curve is 126.7±18.9cm 3 in ICRU plan and 98.2±74.5cm 3 in CTV plan(p=0.0001), respectively. In (On) ICRU planning 22.0cm 3 of CTV volume was not covered by 100% isodose curve in one patient whose residual tumor size is greater than 4cm, while more than 100% dose was irradiated unnecessarily to the normal organ of 62.2±4.8cm 3 other than the tumor in the remaining 10 patients with a residual tumor less than 4cm in size. Bladder dose recommended by ICRU 38 was 90.1±21.3% and 68.7±26.6% in ICRU plan and in CTV plan respectively(p=0.001) while rectal dose recommended by ICRU 38 was 86.4±18.3% and 76.9±15.6% in ICRU plan and in CTV plan, respectively(p=0.08). Bladder and rectum maximum dose was 137.2±50.1%, 101.1±41.8% in ICRU plan and 107.6±47.9%, 86.9±30.8% in CTV plan, respectively

  20. MRI-based treatment plan simulation and adaptation for ion radiotherapy using a classification-based approach

    International Nuclear Information System (INIS)

    Rank, Christopher M; Tremmel, Christoph; Hünemohr, Nora; Nagel, Armin M; Jäkel, Oliver; Greilich, Steffen

    2013-01-01

    In order to benefit from the highly conformal irradiation of tumors in ion radiotherapy, sophisticated treatment planning and simulation are required. The purpose of this study was to investigate the potential of MRI for ion radiotherapy treatment plan simulation and adaptation using a classification-based approach. Firstly, a voxelwise tissue classification was applied to derive pseudo CT numbers from MR images using up to 8 contrasts. Appropriate MR sequences and parameters were evaluated in cross-validation studies of three phantoms. Secondly, ion radiotherapy treatment plans were optimized using both MRI-based pseudo CT and reference CT and recalculated on reference CT. Finally, a target shift was simulated and a treatment plan adapted to the shift was optimized on a pseudo CT and compared to reference CT optimizations without plan adaptation. The derivation of pseudo CT values led to mean absolute errors in the range of 81 - 95 HU. Most significant deviations appeared at borders between air and different tissue classes and originated from partial volume effects. Simulations of ion radiotherapy treatment plans using pseudo CT for optimization revealed only small underdosages in distal regions of a target volume with deviations of the mean dose of PTV between 1.4 - 3.1% compared to reference CT optimizations. A plan adapted to the target volume shift and optimized on the pseudo CT exhibited a comparable target dose coverage as a non-adapted plan optimized on a reference CT. We were able to show that a MRI-based derivation of pseudo CT values using a purely statistical classification approach is feasible although no physical relationship exists. Large errors appeared at compact bone classes and came from an imperfect distinction of bones and other tissue types in MRI. In simulations of treatment plans, it was demonstrated that these deviations are comparable to uncertainties of a target volume shift of 2 mm in two directions indicating that especially

  1. Validating automated kidney stone volumetry in computed tomography and mathematical correlation with estimated stone volume based on diameter.

    Science.gov (United States)

    Wilhelm, Konrad; Miernik, Arkadiusz; Hein, Simon; Schlager, Daniel; Adams, Fabian; Benndorf, Matthias; Fritz, Benjamin; Langer, Mathias; Hesse, Albrecht; Schoenthaler, Martin; Neubauer, Jakob

    2018-06-02

    To validate AutoMated UroLithiasis Evaluation Tool (AMULET) software for kidney stone volumetry and compare its performance to standard clinical practice. Maximum diameter and volume of 96 urinary stones were measured as reference standard by three independent urologists. The same stones were positioned in an anthropomorphic phantom and CT scans acquired in standard settings. Three independent radiologists blinded to the reference values took manual measurements of the maximum diameter and automatic measurements of maximum diameter and volume. An "expected volume" was calculated based on manual diameter measurements using the formula: V=4/3 πr³. 96 stones were analyzed in the study. We had initially aimed to assess 100. Nine were replaced during data acquisition due of crumbling and 4 had to be excluded because the automated measurement did not work. Mean reference maximum diameter was 13.3 mm (5.2-32.1 mm). Correlation coefficients among all measured outcomes were compared. The correlation between the manual and automatic diameter measurements to the reference was 0.98 and 0.91, respectively (pvolumetry is possible and significantly more accurate than diameter-based volumetric calculations. To avoid bias in clinical trials, size should be measured as volume. However, automated diameter measurements are not as accurate as manual measurements.

  2. Radiation Planning Assistant - A Streamlined, Fully Automated Radiotherapy Treatment Planning System

    Science.gov (United States)

    Court, Laurence E.; Kisling, Kelly; McCarroll, Rachel; Zhang, Lifei; Yang, Jinzhong; Simonds, Hannah; du Toit, Monique; Trauernicht, Chris; Burger, Hester; Parkes, Jeannette; Mejia, Mike; Bojador, Maureen; Balter, Peter; Branco, Daniela; Steinmann, Angela; Baltz, Garrett; Gay, Skylar; Anderson, Brian; Cardenas, Carlos; Jhingran, Anuja; Shaitelman, Simona; Bogler, Oliver; Schmeller, Kathleen; Followill, David; Howell, Rebecca; Nelson, Christopher; Peterson, Christine; Beadle, Beth

    2018-01-01

    The Radiation Planning Assistant (RPA) is a system developed for the fully automated creation of radiotherapy treatment plans, including volume-modulated arc therapy (VMAT) plans for patients with head/neck cancer and 4-field box plans for patients with cervical cancer. It is a combination of specially developed in-house software that uses an application programming interface to communicate with a commercial radiotherapy treatment planning system. It also interfaces with a commercial secondary dose verification software. The necessary inputs to the system are a Treatment Plan Order, approved by the radiation oncologist, and a simulation computed tomography (CT) image, approved by the radiographer. The RPA then generates a complete radiotherapy treatment plan. For the cervical cancer treatment plans, no additional user intervention is necessary until the plan is complete. For head/neck treatment plans, after the normal tissue and some of the target structures are automatically delineated on the CT image, the radiation oncologist must review the contours, making edits if necessary. They also delineate the gross tumor volume. The RPA then completes the treatment planning process, creating a VMAT plan. Finally, the completed plan must be reviewed by qualified clinical staff. PMID:29708544

  3. Software quality assurance plan for void fraction instrument

    International Nuclear Information System (INIS)

    Gimera, M.

    1994-01-01

    Waste Tank SY-101 has been the focus of extensive characterization work over the past few years. The waste continually generates gases, most notably hydrogen, which are periodically released from the waste. Gas can be trapped in tank waste in three forms: as void gas (bubbles), dissolved gas, or absorbed gas. Void fraction is the volume percentage of a given sample that is comprised of void gas. The void fraction instrument (VFI) acquires the data necessary to calculate void fraction. This document covers the product, Void Fraction Data Acquisition Software. The void fraction software being developed will have the ability to control the void fraction instrument hardware and acquire data necessary to calculate the void fraction in samples. This document provides the software quality assurance plan, verification and validation plan, and configuration management plan for developing the software for the instrumentation that will be used to obtain void fraction data from Tank SY-101

  4. Automatic bladder segmentation on CBCT for multiple plan ART of bladder cancer using a patient-specific bladder model

    Energy Technology Data Exchange (ETDEWEB)

    Xiangfei, Chai; Hulshof, Maarten; Bel, Arjan [Department of Radiotherapy, Academic medical Center, University of Amsterdam, 1105 AZ, Amsterdam (Netherlands); Van Herk, Marcel; Betgen, Anja [Department of Radiotherapy, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, 1066 CX, Amsterdam (Netherlands)

    2012-06-21

    In multiple plan adaptive radiotherapy (ART) strategies of bladder cancer, a library of plans corresponding to different bladder volumes is created based on images acquired in early treatment sessions. Subsequently, the plan for the smallest PTV safely covering the bladder on cone-beam CT (CBCT) is selected as the plan of the day. The aim of this study is to develop an automatic bladder segmentation approach suitable for CBCT scans and test its ability to select the appropriate plan from the library of plans for such an ART procedure. Twenty-three bladder cancer patients with a planning CT and on average 11.6 CBCT scans were included in our study. For each patient, all CBCT scans were matched to the planning CT on bony anatomy. Bladder contours were manually delineated for each planning CT (for model building) and CBCT (for model building and validation). The automatic segmentation method consisted of two steps. A patient-specific bladder deformation model was built from the training data set of each patient (the planning CT and the first five CBCT scans). Then, the model was applied to automatically segment bladders in the validation data of the same patient (the remaining CBCT scans). Principal component analysis (PCA) was applied to the training data to model patient-specific bladder deformation patterns. The number of PCA modes for each patient was chosen such that the bladder shapes in the training set could be represented by such number of PCA modes with less than 0.1 cm mean residual error. The automatic segmentation started from the bladder shape of a reference CBCT, which was adjusted by changing the weight of each PCA mode. As a result, the segmentation contour was deformed consistently with the training set to fit the bladder in the validation image. A cost function was defined by the absolute difference between the directional gradient field of reference CBCT sampled on the corresponding bladder contour and the directional gradient field of validation

  5. Automatic bladder segmentation on CBCT for multiple plan ART of bladder cancer using a patient-specific bladder model

    International Nuclear Information System (INIS)

    Chai Xiangfei; Hulshof, Maarten; Bel, Arjan; Van Herk, Marcel; Betgen, Anja

    2012-01-01

    In multiple plan adaptive radiotherapy (ART) strategies of bladder cancer, a library of plans corresponding to different bladder volumes is created based on images acquired in early treatment sessions. Subsequently, the plan for the smallest PTV safely covering the bladder on cone-beam CT (CBCT) is selected as the plan of the day. The aim of this study is to develop an automatic bladder segmentation approach suitable for CBCT scans and test its ability to select the appropriate plan from the library of plans for such an ART procedure. Twenty-three bladder cancer patients with a planning CT and on average 11.6 CBCT scans were included in our study. For each patient, all CBCT scans were matched to the planning CT on bony anatomy. Bladder contours were manually delineated for each planning CT (for model building) and CBCT (for model building and validation). The automatic segmentation method consisted of two steps. A patient-specific bladder deformation model was built from the training data set of each patient (the planning CT and the first five CBCT scans). Then, the model was applied to automatically segment bladders in the validation data of the same patient (the remaining CBCT scans). Principal component analysis (PCA) was applied to the training data to model patient-specific bladder deformation patterns. The number of PCA modes for each patient was chosen such that the bladder shapes in the training set could be represented by such number of PCA modes with less than 0.1 cm mean residual error. The automatic segmentation started from the bladder shape of a reference CBCT, which was adjusted by changing the weight of each PCA mode. As a result, the segmentation contour was deformed consistently with the training set to fit the bladder in the validation image. A cost function was defined by the absolute difference between the directional gradient field of reference CBCT sampled on the corresponding bladder contour and the directional gradient field of validation

  6. Balanced program plan. Volume 10. Fusion: analysis for biomedical and environmental research

    International Nuclear Information System (INIS)

    Hungate, F.P.

    1976-06-01

    Development of the Balanced Program Plan for analysis for biomedical and environmental research was initiated in the spring of 1975. The goal was a redefinition of research efforts and priorities to meet ERDA's requirements for a program of health and environmental research to support the development and commercialization of energy technologies. As part of the Balanced Program planning effort the major ERDA-supported multidisciplinary laboratories were assigned responsibility for analyzing the research needs of each of nine energy technologies and describing a research program to meet these needs. The staff of the Division of Biomedical and Environmental Research was assigned the task of defining a research program addressed to each of five biomedical and environmental research categories (characterization, measurement and monitoring; physical and chemical processes and effects; health effects; ecological effects; and integrated assessment and socioeconomic processes and effects) applicable to all energy technologies. The first drafts of these documents were available for a work-shop in June 1975 at which the DBER staff and scientists from the laboratories developed a comprehensive set of program recommendations. Pacific Northwest Laboratory was assigned responsibility for defining research needs and a recommended research program for fusion and fission technologies. This report, Volume 10, presents the input for fusion

  7. Methodological issues in radiation dose-volume outcome analyses: Summary of a joint AAPM/NIH workshop

    International Nuclear Information System (INIS)

    Deasy, Joseph O.; Niemierko, Andrzej; Herbert, Donald; Yan, Di; Jackson, Andrew; Ten Haken, Randall K.; Langer, Mark; Sapareto, Steve

    2002-01-01

    This report represents a summary of presentations at a joint workshop of the National Institutes of Health and the American Association of Physicists in Medicine (AAPM). Current methodological issues in dose-volume modeling are addressed here from several different perspectives. Areas of emphasis include (a) basic modeling issues including the equivalent uniform dose framework and the bootstrap method, (b) issues in the valid use of statistics, including the need for meta-analysis, (c) issues in dealing with organ deformation and its effects on treatment response, (d) evidence for volume effects for rectal complications, (e) the use of volume effect data in liver and lung as a basis for dose escalation studies, and (f) implications of uncertainties in volume effect knowledge on optimized treatment planning. Taken together, these approaches to studying volume effects describe many implications for the development and use of this information in radiation oncology practice. Areas of significant interest for further research include the meta-analysis of clinical data; interinstitutional pooled data analyses of volume effects; analyses of the uncertainties in outcome prediction models, minimal parameter number outcome models for ranking treatment plans (e.g., equivalent uniform dose); incorporation of the effect of motion in the outcome prediction; dose-escalation/isorisk protocols based on outcome models; the use of functional imaging to study radio-response; and the need for further small animal tumor control probability/normal tissue complication probability studies

  8. Routine Radiological Environmental Monitoring Plan. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel Nevada

    1999-12-31

    The U.S. Department of Energy manages the Nevada Test Site in a manner that meets evolving DOE Missions and responds to the concerns of affected and interested individuals and agencies. This Routine Radiological Monitoring Plan addressess complicance with DOE Orders 5400.1 and 5400.5 and other drivers requiring routine effluent monitoring and environmental surveillance on the Nevada Test Site. This monitoring plan, prepared in 1998, addresses the activities conducted onsite NTS under the Final Environmental Impact Statement and Record of Decision. This radiological monitoring plan, prepared on behalf of the Nevada Test Site Landlord, brings together sitewide environmental surveillance; site-specific effluent monitoring; and operational monitoring conducted by various missions, programs, and projects on the NTS. The plan provides an approach to identifying and conducting routine radiological monitoring at the NTS, based on integrated technical, scientific, and regulatory complicance data needs.

  9. Persistently better treatment planning results of intensity-modulated (IMRT) over conformal radiotherapy (3D-CRT) in prostate cancer patients with significant variation of clinical target volume and/or organs-at-risk

    International Nuclear Information System (INIS)

    Fenoglietto, Pascal; Laliberte, Benoit; Allaw, Ali; Ailleres, Norbert; Idri, Katia; Hay, Meng Huor; Moscardo, Carmen Llacer; Gourgou, Sophie; Dubois, Jean-Bernard; Azria, David

    2008-01-01

    Purpose: To compare the dose coverage of planning and clinical target volume (PTV, CTV), and organs-at-risk (OAR) between intensity-modulated (3D-IMRT) and conventional conformal radiotherapy (3D-CRT) before and after internal organ variation in prostate cancer. Methods and materials: We selected 10 patients with clinically significant interfraction volume changes. Patients were treated with 3D-IMRT to 80 Gy (minimum PTV dose of 76 Gy, excluding rectum). Fictitious, equivalent 3D-CRT plans (80 Gy at isocenter, with 95% isodose (76 Gy) coverage of PTV, with rectal blocking above 76 Gy) were generated using the same planning CT data set ('CT planning'). The plans were then also applied to a verification CT scan ('CT verify') obtained at a different moment. PTV, CTV, and OAR dose coverage were compared using non-parametric tests statistics for V95, V90 (% of the volume receiving ≥95 or 90% of the dose) and D50 (dose to 50% of the volume). Results: Mean V95 of the PTV for 'CT planning' was 94.3% (range, 88-99) vs 89.1% (range, 84-94.5) for 3D-IMRT and 3D-CRT (p = 0.005), respectively. Mean V95 of the CTV for 'CT verify' was 97% for both 3D-IMRT and 3D-CRT. Mean D50 of the rectum for 'CT planning' was 26.8 Gy (range, 22-35) vs 43.5 Gy (range, 33.5-50.5) for 3D-IMRT and 3D-CRT (p = 0.0002), respectively. For 'CT verify', this D50 was 31.1 Gy (range, 16.5-44) vs 44.2 Gy (range, 34-55) for 3D-IMRT and 3D-CRT (p = 0.006), respectively. V95 of the rectum was 0% for both plans for 'CT planning', and 2.3% (3D-IMRT) vs 2.1% (3D-CRT) for 'CT verify' (p = non-sig.). Conclusion: Dose coverage of the PTV and OAR was better with 3D-IMRT for each patient and remained so after internal volume changes

  10. Management response plan for the Chemical Safety Vulnerability Working Group report. Volume 1

    International Nuclear Information System (INIS)

    1994-09-01

    The Chemical Safety Vulnerability (CSV) Working Group was established to identify adverse conditions involving hazardous chemicals at DOE facilities that might result in fires or explosions, release of hazardous chemicals to the environment, or exposure of workers or the public to chemicals. A CSV Review was conducted in 146 facilities at 29 sites. Eight generic vulnerabilities were documented related to: abandoned chemicals and chemical residuals; past chemical spills and ground releases; characterization of legacy chemicals and wastes; disposition of legacy chemicals; storage facilities and conditions; condition of facilities and support systems; unanalyzed and unaddressed hazards; and inventory control and tracking. Weaknesses in five programmatic areas were also identified related to: management commitment and planning; chemical safety management programs; aging facilities that continue to operate; nonoperating facilities awaiting deactivation; and resource allocations. Volume 1 contains a discussion of the chemical safety improvements planned or already underway at DOE sites to correct facility or site-specific vulnerabilities. The main part of the report is a discussion of each of the programmatic deficiencies; a description of the tasks to be accomplished; the specific actions to be taken; and the organizational responsibilities for implementation

  11. WE-DE-201-04: Cross Validation of Knowledge-Based Treatment Planning for Prostate LDR Brachytherapy Using Principle Component Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Roper, J; Ghavidel, B; Godette, K; Schreibmann, E [Winship Cancer Institute of Emory University, GA (United States); Chanyavanich, V [Rocky Mountain Cancer Centers, CO (United States)

    2016-06-15

    Purpose: To validate a knowledge-based algorithm for prostate LDR brachytherapy treatment planning. Methods: A dataset of 100 cases was compiled from an active prostate seed implant service. Cases were randomized into 10 subsets. For each subset, the 90 remaining library cases were registered to a common reference frame and then characterized on a point by point basis using principle component analysis (PCA). Each test case was converted to PCA vectors using the same process and compared with each library case using a Mahalanobis distance to evaluate similarity. Rank order PCA scores were used to select the best-matched library case. The seed arrangement was extracted from the best-matched case and used as a starting point for planning the test case. Any subsequent modifications were recorded that required input from a treatment planner to achieve V100>95%, V150<60%, V200<20%. To simulate operating-room planning constraints, seed activity was held constant, and the seed count could not increase. Results: The computational time required to register test-case contours and evaluate PCA similarity across the library was 10s. Preliminary analysis of 2 subsets shows that 9 of 20 test cases did not require any seed modifications to obtain an acceptable plan. Five test cases required fewer than 10 seed modifications or a grid shift. Another 5 test cases required approximately 20 seed modifications. An acceptable plan was not achieved for 1 outlier, which was substantially larger than its best match. Modifications took between 5s and 6min. Conclusion: A knowledge-based treatment planning algorithm for prostate LDR brachytherapy is being cross validated using 100 prior cases. Preliminary results suggest that for this size library, acceptable plans can be achieved without planner input in about half of the cases while varying amounts of planner input are needed in remaining cases. Computational time and planning time are compatible with clinical practice.

  12. Knowledge-based prediction of plan quality metrics in intracranial stereotactic radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Shiraishi, Satomi; Moore, Kevin L., E-mail: kevinmoore@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California 92093 (United States); Tan, Jun [Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas 75490 (United States); Olsen, Lindsey A. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States)

    2015-02-15

    Purpose: The objective of this work was to develop a comprehensive knowledge-based methodology for predicting achievable dose–volume histograms (DVHs) and highly precise DVH-based quality metrics (QMs) in stereotactic radiosurgery/radiotherapy (SRS/SRT) plans. Accurate QM estimation can identify suboptimal treatment plans and provide target optimization objectives to standardize and improve treatment planning. Methods: Correlating observed dose as it relates to the geometric relationship of organs-at-risk (OARs) to planning target volumes (PTVs) yields mathematical models to predict achievable DVHs. In SRS, DVH-based QMs such as brain V{sub 10Gy} (volume receiving 10 Gy or more), gradient measure (GM), and conformity index (CI) are used to evaluate plan quality. This study encompasses 223 linear accelerator-based SRS/SRT treatment plans (SRS plans) using volumetric-modulated arc therapy (VMAT), representing 95% of the institution’s VMAT radiosurgery load from the past four and a half years. Unfiltered models that use all available plans for the model training were built for each category with a stratification scheme based on target and OAR characteristics determined emergently through initial modeling process. Model predictive accuracy is measured by the mean and standard deviation of the difference between clinical and predicted QMs, δQM = QM{sub clin} − QM{sub pred}, and a coefficient of determination, R{sup 2}. For categories with a large number of plans, refined models are constructed by automatic elimination of suspected suboptimal plans from the training set. Using the refined model as a presumed achievable standard, potentially suboptimal plans are identified. Predictions of QM improvement are validated via standardized replanning of 20 suspected suboptimal plans based on dosimetric predictions. The significance of the QM improvement is evaluated using the Wilcoxon signed rank test. Results: The most accurate predictions are obtained when plans are

  13. Knowledge-based prediction of plan quality metrics in intracranial stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Shiraishi, Satomi; Moore, Kevin L.; Tan, Jun; Olsen, Lindsey A.

    2015-01-01

    Purpose: The objective of this work was to develop a comprehensive knowledge-based methodology for predicting achievable dose–volume histograms (DVHs) and highly precise DVH-based quality metrics (QMs) in stereotactic radiosurgery/radiotherapy (SRS/SRT) plans. Accurate QM estimation can identify suboptimal treatment plans and provide target optimization objectives to standardize and improve treatment planning. Methods: Correlating observed dose as it relates to the geometric relationship of organs-at-risk (OARs) to planning target volumes (PTVs) yields mathematical models to predict achievable DVHs. In SRS, DVH-based QMs such as brain V 10Gy (volume receiving 10 Gy or more), gradient measure (GM), and conformity index (CI) are used to evaluate plan quality. This study encompasses 223 linear accelerator-based SRS/SRT treatment plans (SRS plans) using volumetric-modulated arc therapy (VMAT), representing 95% of the institution’s VMAT radiosurgery load from the past four and a half years. Unfiltered models that use all available plans for the model training were built for each category with a stratification scheme based on target and OAR characteristics determined emergently through initial modeling process. Model predictive accuracy is measured by the mean and standard deviation of the difference between clinical and predicted QMs, δQM = QM clin − QM pred , and a coefficient of determination, R 2 . For categories with a large number of plans, refined models are constructed by automatic elimination of suspected suboptimal plans from the training set. Using the refined model as a presumed achievable standard, potentially suboptimal plans are identified. Predictions of QM improvement are validated via standardized replanning of 20 suspected suboptimal plans based on dosimetric predictions. The significance of the QM improvement is evaluated using the Wilcoxon signed rank test. Results: The most accurate predictions are obtained when plans are stratified based on

  14. FACTAR validation

    International Nuclear Information System (INIS)

    Middleton, P.B.; Wadsworth, S.L.; Rock, R.C.; Sills, H.E.; Langman, V.J.

    1995-01-01

    A detailed strategy to validate fuel channel thermal mechanical behaviour codes for use of current power reactor safety analysis is presented. The strategy is derived from a validation process that has been recently adopted industry wide. Focus of the discussion is on the validation plan for a code, FACTAR, for application in assessing fuel channel integrity safety concerns during a large break loss of coolant accident (LOCA). (author)

  15. A planning quality evaluation tool for prostate adaptive IMRT based on machine learning

    International Nuclear Information System (INIS)

    Zhu Xiaofeng; Ge Yaorong; Li Taoran; Thongphiew, Danthai; Yin Fangfang; Wu, Q Jackie

    2011-01-01

    Purpose: To ensure plan quality for adaptive IMRT of the prostate, we developed a quantitative evaluation tool using a machine learning approach. This tool generates dose volume histograms (DVHs) of organs-at-risk (OARs) based on prior plans as a reference, to be compared with the adaptive plan derived from fluence map deformation. Methods: Under the same configuration using seven-field 15 MV photon beams, DVHs of OARs (bladder and rectum) were estimated based on anatomical information of the patient and a model learned from a database of high quality prior plans. In this study, the anatomical information was characterized by the organ volumes and distance-to-target histogram (DTH). The database consists of 198 high quality prostate plans and was validated with 14 cases outside the training pool. Principal component analysis (PCA) was applied to DVHs and DTHs to quantify their salient features. Then, support vector regression (SVR) was implemented to establish the correlation between the features of the DVH and the anatomical information. Results: DVH/DTH curves could be characterized sufficiently just using only two or three truncated principal components, thus, patient anatomical information was quantified with reduced numbers of variables. The evaluation of the model using the test data set demonstrated its accuracy ∼80% in prediction and effectiveness in improving ART planning quality. Conclusions: An adaptive IMRT plan quality evaluation tool based on machine learning has been developed, which estimates OAR sparing and provides reference in evaluating ART.

  16. A validation of carbon fiber imaging couch top modeling in two radiation therapy treatment planning systems: Philips Pinnacle3 and BrainLAB iPlan RT Dose

    Directory of Open Access Journals (Sweden)

    Njeh Christopher F

    2012-11-01

    Full Text Available Abstract Background Carbon fiber (CF is now the material of choice for radiation therapy couch tops. Initial designs included side metal bars for rigidity; however, with the advent of IGRT, involving on board imaging, new thicker CF couch tops without metal bars have been developed. The new design allows for excellent imaging at the expense of potentially unacceptable dose attenuation and perturbation. Objectives We set out to model the BrainLAB imaging couch top (ICT in Philips Pinnacle3 treatment planning system (TPS, to validate the already modeled ICT in BrainLAB iPlan RT Dose treatment planning system and to compute the magnitude of the loss in skin sparing. Results Using CF density of 0.55 g/cm3 and foam density of 0.03 g/cm3, we demonstrated an excellent agreement between measured dose and Pinnacle3 TPS computed dose using 6 MV beam. The agreement was within 1% for all gantry angle measured except for 120o, which was 1.8%. The measured and iPlan RT Dose TPS computed dose agreed to within 1% for all gantry angles and field sizes measured except for 100o where the agreement was 1.4% for 10 cm × 10 cm field size. Predicted attenuation through the couch by iPlan RT Dose TPS (3.4% - 9.5% and Pinnacle3 TPS (2% - 6.6% were within the same magnitude and similar to previously reported in the literature. Pinnacle3 TPS estimated an 8% to 20% increase in skin dose with increase in field size. With the introduction of the CF couch top, it estimated an increase in skin dose by approximately 46 - 90%. The clinical impact of omitting the couch in treatment planning will be dependent on the beam arrangement, the percentage of the beams intersecting the couch and their angles of incidence. Conclusion We have successfully modeled the ICT in Pinnacle3 TPS and validated the modeled ICT in iPlan RT Dose. It is recommended that the ICT be included in treatment planning for all treatments that involve posteriors beams. There is a significant

  17. RELAP-7 Software Verification and Validation Plan - Requirements Traceability Matrix (RTM) Part 2: Code Assessment Strategy, Procedure, and RTM Update

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jun Soo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Choi, Yong Joon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    This document addresses two subjects involved with the RELAP-7 Software Verification and Validation Plan (SVVP): (i) the principles and plan to assure the independence of RELAP-7 assessment through the code development process, and (ii) the work performed to establish the RELAP-7 assessment plan, i.e., the assessment strategy, literature review, and identification of RELAP-7 requirements. Then, the Requirements Traceability Matrices (RTMs) proposed in previous document (INL-EXT-15-36684) are updated. These RTMs provide an efficient way to evaluate the RELAP-7 development status as well as the maturity of RELAP-7 assessment through the development process.

  18. INTRA - Maintenance and Validation. Final Report

    International Nuclear Information System (INIS)

    Edlund, Ove; Jahn, Hermann; Yitbarek, Z.

    2002-05-01

    The INTRA code is specified by the ITER Joint Central Team and the European Community as a reference code for safety analyses of Tokamak type fusion reactors. INTRA has been developed by GRS and Studsvik EcoSafe to analyse integrated behaviours such as pressurisation, chemical reactions and temperature transients inside the plasma chamber and adjacent rooms, following postulated accidents, e.g. ingress of coolant water or air. Important results of the ICE and EVITA experiments, which became available early 2001, were used to validate and improve specific INTRA models. Large efforts were spent on the behaviour of water and steam injection into a low-pressure volumes at high temperature as well as on the modelling of boiling of water in contact with hot surfaces. As a result of this a new version, INTRA/Mod4, was documented and issued. The work included implementation and validation of selected physical models in the code, maintaining code versions, preparation review and distribution of code documents, and monitoring of the code related activities being performed by the GRS under a separate contract. The INTRA/Mod4 Manual and Code Description is documented in four volumes: Volume 1 - Physical Modelling, Volume 2 - User's Manual, Volume 3 -Code Structure and Volume 4 - Validation

  19. Interactively exploring optimized treatment plans

    International Nuclear Information System (INIS)

    Rosen, Isaac; Liu, H. Helen; Childress, Nathan; Liao Zhongxing

    2005-01-01

    Purpose: A new paradigm for treatment planning is proposed that embodies the concept of interactively exploring the space of optimized plans. In this approach, treatment planning ignores the details of individual plans and instead presents the physician with clinical summaries of sets of solutions to well-defined clinical goals in which every solution has been optimized in advance by computer algorithms. Methods and materials: Before interactive planning, sets of optimized plans are created for a variety of treatment delivery options and critical structure dose-volume constraints. Then, the dose-volume parameters of the optimized plans are fit to linear functions. These linear functions are used to show in real time how the target dose-volume histogram (DVH) changes as the DVHs of the critical structures are changed interactively. A bitmap of the space of optimized plans is used to restrict the feasible solutions. The physician selects the critical structure dose-volume constraints that give the desired dose to the planning target volume (PTV) and then those constraints are used to create the corresponding optimized plan. Results: The method is demonstrated using prototype software, Treatment Plan Explorer (TPEx), and a clinical example of a patient with a tumor in the right lung. For this example, the delivery options included 4 open beams, 12 open beams, 4 wedged beams, and 12 wedged beams. Beam directions and relative weights were optimized for a range of critical structure dose-volume constraints for the lungs and esophagus. Cord dose was restricted to 45 Gy. Using the interactive interface, the physician explored how the tumor dose changed as critical structure dose-volume constraints were tightened or relaxed and selected the best compromise for each delivery option. The corresponding treatment plans were calculated and compared with the linear parameterization presented to the physician in TPEx. The linear fits were best for the maximum PTV dose and worst

  20. Eleventh annual Department of Energy low-level waste management conference. Volume 2: Low-level waste strategy and planning, decontamination and decommissioning, compliance monitoring

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-11-01

    Nineteen papers are presented in volume 2. The 11 papers in the LLW Strategy and Planning section discuss plans for disposal facilities in Texas, Pennsylvania, Hanford, the Southwest and Southeast Compacts, and others. Three papers discuss decontamination technology and activities. Environmental monitoring requirements and recommendations at LLW facilities are discussed in 5 papers. Papers have been processed separately for inclusion on the data base.

  1. Defining internal target volume (ITV) for hepatocellular carcinoma using four-dimensional CT

    International Nuclear Information System (INIS)

    X, Mian; Liu Mengzhong; Deng Xiaowu; Zhang Li; Huang Xiaoyan; Liu Hui; Li Qiaoqiao; Hu Yonghong; Cai Ling; Cui Nianji

    2007-01-01

    Background and purpose: To define individualized internal target volume (ITV) for hepatocellular carcinoma using four-dimensional computed tomography (4DCT). Materials and methods: Gross tumor volumes (GTVs) and clinical target volumes (CTVs) were contoured on all 10 respiratory phases of 4DCT scans in 10 patients with hepatocellular carcinoma. The 3D and 4D treatment plans were performed for each patient using two different planning target volumes (PTVs): (1) PTV 3D was derived from a single CTV plus conventional margins; (2) PTV 4D was derived from ITV 4D , which encompassed all 10 CTVs plus setup margins (SMs). The volumes of PTVs and dose distribution were compared between the two plans. Results: The average PTV volume of the 4D plans (328.4 ± 152.2 cm 3 ) was less than 3D plans (407.0 ± 165.6 cm 3 ). The 4D plans spared more surrounding normal tissues than 3D plans, especially normal liver. Compared with 3D plans, the mean dose to normal liver (MDTNL) decreased from 22.7 to 20.3 Gy. Without increasing the normal tissue complication probability (NTCP), the 4D plans allowed for increasing the calculated dose from 50.4 ± 1.3 to 54.2 ± 2.6 Gy, an average increase of 7.5% (range 4.0-16.0%). Conclusions: The conventional 3D plans can result in geometric miss and include excess normal tissues. The 4DCT-based plans can reduce the target volumes to spare more normal tissues and allow dose escalation compared with 3D plans

  2. Dose-volume and biological-model based comparison between helical tomotherapy and (inverse-planned) IMAT for prostate tumours

    International Nuclear Information System (INIS)

    Iori, Mauro; Cattaneo, Giovanni Mauro; Cagni, Elisabetta; Fiorino, Claudio; Borasi, Gianni; Riccardo, Calandrino; Iotti, Cinzia; Fazio, Ferruccio; Nahum, Alan E.

    2008-01-01

    Background and purpose: Helical tomotherapy (HT) and intensity-modulated arc therapy (IMAT) are two arc-based approaches to the delivery of intensity-modulated radiotherapy (IMRT). Through plan comparisons we have investigated the potential of IMAT, both with constant (conventional or IMAT-C) and variable (non-conventional or IMAT-NC, a theoretical exercise) dose-rate, to serve as an alternative to helical tomotherapy. Materials and methods: Six patients with prostate tumours treated by HT with a moderately hypo-fractionated protocol, involving a simultaneous integrated boost, were re-planned as IMAT treatments. A method for IMAT inverse-planning using a commercial module for static IMRT combined with a multi-leaf collimator (MLC) arc-sequencing was developed. IMAT plans were compared to HT plans in terms of dose statistics and radiobiological indices. Results: Concerning the planning target volume (PTV), the mean doses for all PTVs were similar for HT and IMAT-C plans with minimum dose, target coverage, equivalent uniform dose (EUD) and tumour control probability (TCP) values being generally higher for HT; maximum dose and degree of heterogeneity were instead higher for IMAT-C. In relation to organs at risk, mean doses and normal tissue complication probability (NTCP) values were similar between the two modalities, except for the penile bulb where IMAT was significantly better. Re-normalizing all plans to the same rectal toxicity (NTCP = 5%), the HT modality yielded higher TCP than IMAT-C but there was no significant difference between HT and IMAT-NC. The integral dose with HT was higher than that for IMAT. Conclusions: with regards to the plan analysis, the HT is superior to IMAT-C in terms of target coverage and dose homogeneity within the PTV. Introducing dose-rate variation during arc-rotation, not deliverable with current linac technology, the simulations result in comparable plan indices between (IMAT-NC) and HT

  3. Sandia software guidelines: Software quality planning

    Energy Technology Data Exchange (ETDEWEB)

    1987-08-01

    This volume is one in a series of Sandia Software Guidelines intended for use in producing quality software within Sandia National Laboratories. In consonance with the IEEE Standard for Software Quality Assurance Plans, this volume identifies procedures to follow in producing a Software Quality Assurance Plan for an organization or a project, and provides an example project SQA plan. 2 figs., 4 tabs.

  4. A Treatment Planning Analysis of Inverse-Planned and Forward-Planned Intensity-Modulated Radiation Therapy in Nasopharyngeal Carcinoma

    International Nuclear Information System (INIS)

    Poon, Ian M; Xia Ping; Weinberg, Vivien; Sultanem, Khalil; Akazawa, Clayton C.; Akazawa, Pamela C.; Verhey, Lynn; Quivey, Jeanne Marie; Lee, Nancy

    2007-01-01

    Purpose: To compare dose-volume histograms of target volumes and organs at risk in 57 patients with nasopharyngeal carcinoma (NPC) with inverse- (IP) or forward-planned (FP) intensity-modulated radiation treatment (IMRT). Methods and Materials: The DVHs of 57 patients with NPC with IMRT with or without chemotherapy were reviewed. Thirty-one patients underwent IP IMRT, and 26 patients underwent FP IMRT. Treatment goals were to prescribe a minimum dose of 66-70 Gy for gross tumor volume and 59.4 Gy for planning target volume to greater than 95% of the volume. Multiple selected end points were used to compare dose-volume histograms of the targets, including minimum, mean, and maximum doses; percentage of target volume receiving less than 90% (1-V90%), less than 95% (1-V95%), and greater than 105% (1-V105%). Dose-volume histograms of organs at risk were evaluated with characteristic end points. Results: Both planning methods provided excellent target coverage with no statistically significant differences found, although a trend was suggested in favor of improved target coverage with IP IMRT in patients with T3/T4 NPC (p = 0.10). Overall, IP IMRT statistically decreased the dose to the parotid gland, temporomandibular joint, brain stem, and spinal cord overall, whereas IP led to a dose decrease to the middle/inner ear in only the T1/T2 subgroup. Conclusions: Use of IP and FP IMRT can lead to good target coverage while maintaining critical structures within tolerance. The IP IMRT selectively spared these critical organs to a greater degree and should be considered the standard of treatment in patients with NPC, particularly those with T3/T4. The FP IMRT is an effective second option in centers with limited IP IMRT capacity. As a modification of conformal techniques, the human/departmental resources to incorporate FP-IMRT should be nominal

  5. Anatomic Boundaries of the Clinical Target Volume (Prostate Bed) After Radical Prostatectomy

    International Nuclear Information System (INIS)

    Wiltshire, Kirsty L.; Brock, Kristy K.; Haider, Masoom A.; Zwahlen, Daniel; Kong, Vickie; Chan, Elisa; Moseley, Joanne; Bayley, Andrew; Catton, Charles; Chung, Peter W.M.; Gospodarowicz, Mary; Milosevic, Michael; Kneebone, Andrew; Warde, Padraig; Menard, Cynthia

    2007-01-01

    Purpose: We sought to derive and validate an interdisciplinary consensus definition for the anatomic boundaries of the postoperative clinical target volume (CTV, prostate bed). Methods and Materials: Thirty one patients who had planned for radiotherapy after radical prostatectomy were enrolled and underwent computed tomography and magnetic resonance imaging (MRI) simulation prior to radiotherapy. Through an iterative process of consultation and discussion, an interdisciplinary consensus definition was derived based on a review of published data, patterns of local failure, surgical practice, and radiologic anatomy. In validation, we analyzed the distribution of surgical clips in reference to the consensus CTV and measured spatial uncertainties in delineating the CTV and vesicourethral anastomosis. Clinical radiotherapy plans were retrospectively evaluated against the consensus CTV (prostate bed). Results: Anatomic boundaries of the consensus CTV (prostate bed) are described. Surgical clips (n = 339) were well distributed throughout the CTV. The vesicourethral anastomosis was accurately localized using central sagittal computed tomography reconstruction, with a mean ± standard deviation uncertainty of 1.8 ± 2.5 mm. Delineation uncertainties were small for both MRI and computed tomography (mean reproducibility, 0-3.8 mm; standard deviation, 1.0-2.3); they were most pronounced in the anteroposterior and superoinferior dimensions and at the superior/posterior-most aspect of the CTV. Retrospectively, the mean ± standard deviation CTV (prostate bed) percentage of volume receiving 100% of prescribed dose was only 77% ± 26%. Conclusions: We propose anatomic boundaries for the CTV (prostate bed) and present evidence supporting its validity. In the absence of gross recurrence, the role of MRI in delineating the CTV remains to be confirmed. The CTV is larger than historically practiced at our institution and should be encompassed by a microscopic tumoricidal dose

  6. Validation of attenuation-corrected equilibrium radionuclide angiographic determinations of right ventricular volume: comparison with cast-validated biplane cineventriculography

    International Nuclear Information System (INIS)

    Dell'Italia, L.J.; Starling, M.R.; Walsh, R.A.; Badke, F.R.; Lasher, J.C.; Blumhardt, R.

    1985-01-01

    To determine the accuracy of attenuation-corrected equilibrium radionuclide angiographic determinations of right ventricular volumes, the authors initially studied 14 postmortem human right ventricular casts by water displacement and biplane cineventriculography. Biplane cineventriculographic right ventricular cast volumes, calculated by a modification of Simpson's rule algorithm, correlated well with right ventricular cast volumes measured by water displacement (r = .97, y = 8 + 0.88x, SEE = 6 ml). Moreover, the mean volumes obtained by both methods were no different (73 +/- 28 vs 73 +/- 25 ml). Subsequently, they studied 16 patients by both biplane cineventriculography and equilibrium radionuclide angiography. The uncorrected radionuclide right ventricular volumes were calculated by normalizing background corrected end-diastolic and end-systolic counts from hand-drawn regions of interest obtained by phase analysis for cardiac cycles processed, frame rate, and blood sample counts. Attenuation correction was performed by a simple geometric method. The attenuation-corrected radionuclide right ventricular end-diastolic volumes correlated with the cineventriculographic end-diastolic volumes (r = .91, y = 3 + 0.92x, SEE = 27 ml). Similarly, the attenuation-corrected radionuclide right ventricular end-systolic volumes correlated with the cineventriculographic end-systolic volumes (r = .93, y = - 1 + 0.91x, SEE = 16 ml). Also, the mean attenuation-corrected radionuclide end-diastolic and end-systolic volumes were no different than the average cineventriculographic end-diastolic and end-systolic volumes (160 +/- 61 and 83 +/- 44 vs 170 +/- 61 and 86 +/- 43 ml, respectively)

  7. Task Analysis and Descriptions of Required Job Competencies for Robotics/Automated Systems Technicians. Final Report. Volume 2. Curriculum Planning Guide.

    Science.gov (United States)

    Hull, Daniel M.; Lovett, James E.

    This volume of the final report for the Robotics/Automated Systems Technician (RAST) curriculum project is a curriculum planning guide intended for school administrators, faculty, and student counselors/advisors. It includes step-by-step procedures to help institutions evaluate their community's needs and their capabilities to meet these needs in…

  8. Change in Seroma Volume During Whole-Breast Radiation Therapy

    International Nuclear Information System (INIS)

    Sharma, Rajiv; Spierer, Marnee; Mutyala, Subhakar; Thawani, Nitika; Cohen, Hillel W.; Hong, Linda; Garg, Madhur K.; Kalnicki, Shalom

    2009-01-01

    Purpose: After breast-conserving surgery, a seroma often forms in the surgical cavity. If not drained, it may affect the volume of tumor bed requiring a boost after whole-breast radiation therapy (WBRT). Our objective was to evaluate the change in seroma volume that occurs during WBRT, before boost planning. Methods and Materials: A retrospective review was performed of women receiving breast-conserving therapy with evidence of seroma at the time of WBRT planning. Computed tomography (CT) simulation was performed before WBRT and before the tumor bed boost. All patients received either a hypofractionated (42.4 Gy/16 fraction + 9.6 Gy/4 fraction boost) or standard fractionated (50.4 Gy/28 fraction + 10 Gy/5 fraction boost) regimen. Seroma volumes were contoured and compared on CT at the time of WBRT simulation and tumor bed boost planning. Results: Twenty-four patients with evidence of seroma were identified and all patients received WBRT without drainage of the seroma. Mean seroma volume before WBRT and at boost planning were significantly different at 65.7 cm 3 (SD, 50.5 cm 3 ) and 35.6 cm 3 (SD, 24.8 cm 3 ), respectively (p < 0.001). Mean and median reduction in seroma volume during radiation were 39.6% (SD, 23.8%) and 46.2% (range, 10.7-76.7%), respectively. Fractionation schedule was not correlated with change in seroma volume. Length of time from surgery to start of radiation therapy showed an inverse correlation with change in seroma volume (Pearson correlation r = -0.53, p < 0.01). Conclusions: The volume of seroma changes significantly during WBRT. Consequently, the accuracy of breast boost planning is likely affected, as is the volume of normal breast tissue irradiated. CT-based boost planning before boost irradiation is suggested to ensure appropriate coverage.

  9. MO-G-304-01: FEATURED PRESENTATION: Expanding the Knowledge Base for Data-Driven Treatment Planning: Incorporating Patient Outcome Models

    International Nuclear Information System (INIS)

    Robertson, SP; Quon, H; Cheng, Z; Moore, JA; Bowers, M; McNutt, TR

    2015-01-01

    Purpose: To extend the capabilities of knowledge-based treatment planning beyond simple dose queries by incorporating validated patient outcome models. Methods: From an analytic, relational database of 684 head and neck cancer patients, 372 patients were identified having dose data for both left and right parotid glands as well as baseline and follow-up xerostomia assessments. For each existing patient, knowledge-based treatment planning was simulated for by querying the dose-volume histograms and geometric shape relationships (overlap volume histograms) for all other patients. Dose predictions were captured at normalized volume thresholds (NVT) of 0%, 10%, 20, 30%, 40%, 50%, and 85% and were compared with the actual achieved doses using the Wilcoxon signed-rank test. Next, a logistic regression model was used to predict the maximum severity of xerostomia up to three months following radiotherapy. Baseline xerostomia scores were subtracted from follow-up assessments and were also included in the model. The relative risks from predicted doses and actual doses were computed and compared. Results: The predicted doses for both parotid glands were significantly less than the achieved doses (p < 0.0001), with differences ranging from 830 cGy ± 1270 cGy (0% NVT) to 1673 cGy ± 1197 cGy (30% NVT). The modelled risk of xerostomia ranged from 54% to 64% for achieved doses and from 33% to 51% for the dose predictions. Relative risks varied from 1.24 to 1.87, with maximum relative risk occurring at 85% NVT. Conclusions: Data-driven generation of treatment planning objectives without consideration of the underlying normal tissue complication probability may Result in inferior plans, even if quality metrics indicate otherwise. Inclusion of complication models in knowledge-based treatment planning is necessary in order to close the feedback loop between radiotherapy treatments and patient outcomes. Future work includes advancing and validating complication models in the context

  10. MO-G-304-01: FEATURED PRESENTATION: Expanding the Knowledge Base for Data-Driven Treatment Planning: Incorporating Patient Outcome Models

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, SP; Quon, H; Cheng, Z; Moore, JA; Bowers, M; McNutt, TR [Johns Hopkins University, Baltimore, MD (United States)

    2015-06-15

    Purpose: To extend the capabilities of knowledge-based treatment planning beyond simple dose queries by incorporating validated patient outcome models. Methods: From an analytic, relational database of 684 head and neck cancer patients, 372 patients were identified having dose data for both left and right parotid glands as well as baseline and follow-up xerostomia assessments. For each existing patient, knowledge-based treatment planning was simulated for by querying the dose-volume histograms and geometric shape relationships (overlap volume histograms) for all other patients. Dose predictions were captured at normalized volume thresholds (NVT) of 0%, 10%, 20, 30%, 40%, 50%, and 85% and were compared with the actual achieved doses using the Wilcoxon signed-rank test. Next, a logistic regression model was used to predict the maximum severity of xerostomia up to three months following radiotherapy. Baseline xerostomia scores were subtracted from follow-up assessments and were also included in the model. The relative risks from predicted doses and actual doses were computed and compared. Results: The predicted doses for both parotid glands were significantly less than the achieved doses (p < 0.0001), with differences ranging from 830 cGy ± 1270 cGy (0% NVT) to 1673 cGy ± 1197 cGy (30% NVT). The modelled risk of xerostomia ranged from 54% to 64% for achieved doses and from 33% to 51% for the dose predictions. Relative risks varied from 1.24 to 1.87, with maximum relative risk occurring at 85% NVT. Conclusions: Data-driven generation of treatment planning objectives without consideration of the underlying normal tissue complication probability may Result in inferior plans, even if quality metrics indicate otherwise. Inclusion of complication models in knowledge-based treatment planning is necessary in order to close the feedback loop between radiotherapy treatments and patient outcomes. Future work includes advancing and validating complication models in the context

  11. Treatment planning for multicatheter interstitial brachytherapy of breast cancer – from Paris system to anatomy-based inverse planning

    Directory of Open Access Journals (Sweden)

    Tibor Major

    2017-02-01

    Full Text Available In the last decades, treatment planning for multicatheter interstitial breast brachytherapy has evolved considerably from fluoroscopy-based 2D to anatomy-based 3D planning. To plan the right positions of the catheters, ultrasound or computed tomography (CT imaging can be used, but the treatment plan is always based on postimplant CT images. With CT imaging, the 3D target volume can be defined more precisely and delineation of the organs at risk volumes is also possible. Consequently, parameters calculated from dose-volume histogram can be used for quantitative plan evaluation. The catheter reconstruction is also easier and faster on CT images compared to X-ray films. In high dose rate brachytherapy, using a stepping source, a number of forward dose optimization methods (manual, geometrical, on dose points, graphical are available to shape the dose distribution to the target volume, and these influence dose homogeneities to different extent. Currently, inverse optimization algorithms offer new possibilities to improve dose distributions further considering the requirements for dose coverage, dose homogeneity, and dose to organs at risk simultaneously and automatically. In this article, the evolvement of treatment planning for interstitial breast implants is reviewed, different forward optimization methods are discussed, and dose-volume parameters used for quantitative plan evaluation are described. Finally, some questions of the inverse optimization method are investigated and initial experiences of the authors are presented.

  12. What margins should be added to the clinical target volume in radiotherapy treatment planning of lung cancer?

    International Nuclear Information System (INIS)

    Ekberg, L.; Wittgren, L.; Holmberg, O.

    1995-01-01

    When defining the planning target volume (PTV) in radiotherapy treatment planning, it is vital to add geometrical margins of normal tissue around the clinical target volume (CTV). This is to ensure that the whole CTV will receive the planned absorbed dose taking into account both set-up deviations and target movements as well as other geometrical variations in the treatment chain. The problem is our limited knowledge of how large these margins should be. To assess the size of needed margins around the CTV in conformal radiotherapy of lung cancer, electronic portal imaging was employed in 232 irradiation field set-ups of 14 patients. This was done in order to quantify the uncertainty in the execution of treatment considering patient movement and set-up displacements. For an estimation of the added geometrical variation from target movement during irradiation, fluoroscopy was used at the simulation of the irradiation fields. The set-up study showed an average systematic deviation for all individual fields of 3.1 mm and an average maximal systematic deviation (in either transversal or craniocaudal direction) of 4.8 mm. The random errors can be described by an average standard deviation of 2.8 mm for all fields in either direction. Major gradual displacements as a function of time was also detected in one of the patients. CTV-movements of several millimetres during respiration could be observed. It was also seen that heartbeats could add to CTV-movements during irradiation with an equal magnitude. The combined effect of these factors are considered when making an overall estimation of margins that should be added to the CTV

  13. WE-AB-209-07: Explicit and Convex Optimization of Plan Quality Metrics in Intensity-Modulated Radiation Therapy Treatment Planning

    International Nuclear Information System (INIS)

    Engberg, L; Eriksson, K; Hardemark, B; Forsgren, A

    2016-01-01

    Purpose: To formulate objective functions of a multicriteria fluence map optimization model that correlate well with plan quality metrics, and to solve this multicriteria model by convex approximation. Methods: In this study, objectives of a multicriteria model are formulated to explicitly either minimize or maximize a dose-at-volume measure. Given the widespread agreement that dose-at-volume levels play important roles in plan quality assessment, these objectives correlate well with plan quality metrics. This is in contrast to the conventional objectives, which are to maximize clinical goal achievement by relating to deviations from given dose-at-volume thresholds: while balancing the new objectives means explicitly balancing dose-at-volume levels, balancing the conventional objectives effectively means balancing deviations. Constituted by the inherently non-convex dose-at-volume measure, the new objectives are approximated by the convex mean-tail-dose measure (CVaR measure), yielding a convex approximation of the multicriteria model. Results: Advantages of using the convex approximation are investigated through juxtaposition with the conventional objectives in a computational study of two patient cases. Clinical goals of each case respectively point out three ROI dose-at-volume measures to be considered for plan quality assessment. This is translated in the convex approximation into minimizing three mean-tail-dose measures. Evaluations of the three ROI dose-at-volume measures on Pareto optimal plans are used to represent plan quality of the Pareto sets. Besides providing increased accuracy in terms of feasibility of solutions, the convex approximation generates Pareto sets with overall improved plan quality. In one case, the Pareto set generated by the convex approximation entirely dominates that generated with the conventional objectives. Conclusion: The initial computational study indicates that the convex approximation outperforms the conventional objectives

  14. Adaptive Radiotherapy Planning on Decreasing Gross Tumor Volumes as Seen on Megavoltage Computed Tomography Images

    International Nuclear Information System (INIS)

    Woodford, Curtis; Yartsev, Slav; Dar, A. Rashid; Bauman, Glenn; Van Dyk, Jake

    2007-01-01

    Purpose: To evaluate gross tumor volume (GTV) changes for patients with non-small-cell lung cancer by using daily megavoltage (MV) computed tomography (CT) studies acquired before each treatment fraction on helical tomotherapy and to relate the potential benefit of adaptive image-guided radiotherapy to changes in GTV. Methods and Materials: Seventeen patients were prescribed 30 fractions of radiotherapy on helical tomotherapy for non-small-cell lung cancer at London Regional Cancer Program from Dec 2005 to March 2007. The GTV was contoured on the daily MVCT studies of each patient. Adapted plans were created using merged MVCT-kilovoltage CT image sets to investigate the advantages of replanning for patients with differing GTV regression characteristics. Results: Average GTV change observed over 30 fractions was -38%, ranging from -12 to -87%. No significant correlation was observed between GTV change and patient's physical or tumor features. Patterns of GTV changes in the 17 patients could be divided broadly into three groups with distinctive potential for benefit from adaptive planning. Conclusions: Changes in GTV are difficult to predict quantitatively based on patient or tumor characteristics. If changes occur, there are points in time during the treatment course when it may be appropriate to adapt the plan to improve sparing of normal tissues. If GTV decreases by greater than 30% at any point in the first 20 fractions of treatment, adaptive planning is appropriate to further improve the therapeutic ratio

  15. Inverse planning and class solutions for brachytherapy treatment planning

    International Nuclear Information System (INIS)

    Trnkova, P.

    2010-01-01

    Brachytherapy or interventional radiooncology is a method of radiation therapy. It is a method, where a small encapsulated radioactive source is placed near to / in the tumour and therefore delivers high doses directly to the target volume. Organs at risk (OARs) are spared due to the inverse square dose fall-off. In the past years there was a slight stagnation in the development of techniques for brachytherapy treatment. While external beam radiotherapy became more and more sophisticated, in brachytherapy traditional methods have been still used. Recently, 3D imaging was considered also as the modality for brachytherapy and more precise brachytherapy could expand. Nowadays, an image guided brachytherapy is state-of-art in many centres. Integration of imaging methods lead to the dose distribution individually tailored for each patient. Treatment plan optimization is mostly performed manually as an adaptation of a standard loading pattern. Recently, inverse planning approaches have been introduced into brachytherapy. The aim of this doctoral thesis was to analyze inverse planning and to develop concepts how to integrate inverse planning into cervical cancer brachytherapy. First part of the thesis analyzes the Hybrid Inverse treatment Planning and Optimization (HIPO) algorithm and proposes a workflow how to safely work with this algorithm. The problem of inverse planning generally is that only the dose and volume parameters are taken into account and spatial dose distribution is neglected. This fact can lead to unwanted high dose regions in a normal tissue. A unique implementation of HIPO into the treatment planning system using additional features enabled to create treatment plans similar to the plans resulting from manual optimization and to shape the high dose regions inside the CTV. In the second part the HIPO algorithm is compared to the Inverse Planning Simulated Annealing (IPSA) algorithm. IPSA is implemented into the commercial treatment planning system. It

  16. Metodología para elaborar el Plan Maestro de Validación de los procesos de producción del Centro Nacional de Sanidad Agropecuaria Methodology to design the Master Plan of Validation of production processes of National Center of Agricultural Health

    Directory of Open Access Journals (Sweden)

    Nivian Montes de Oca

    2010-06-01

    Full Text Available La metodología para la elaboración del Plan Maestro de Validación de los procesos de producción del Centro Nacional de Sanidad Agropecuaria, se diseñó a partir de los requisitos contenidos en la Regulación 16 del 2006 de Buenas Prácticas de Fabricación de medicamentos. Abarcó la política de la organización para la actividad de validación su estructura organizativa, las instalaciones, sistemas, equipos y procesos que se deben validar; el formato de la documentación a utilizar; la planificación y calendario de cada actividad; los resultados de cada protocolo ejecutado, el control de los cambios que se generan; un resumen de las validaciones anteriores; cumplimiento del plan propuesto; las conclusiones donde se precisan de forma resumida si los procesos validados están bajo control, los resultados más relevantes, así como las acciones correctivas y preventivas a tomar; por último se define la distribución de toda la información generada, conformando así el Plan Maestro de Validación. Este sistema de validación se muestra a través de procedimientos, protocolos y registros aplicados en el proceso de fabricación de Surfacen®, medicamento para uso humano que se fabrica en el Centro Nacional de Sanidad Agropecuaria.The methodology to design the Validation Master Plan the production processes of National Center of Agricultural Health was created from the requirements present in the Regulation 16, 2006 of Good Practices of drugs manufacture including the organization policy for validation activity of its organizing structure, installations, systems, equipments and processes to be validated, documentation format used, planning and calendar of each activity; the results from each protocol performed, the generating changes control, abstract of prior validations, fulfillment of proposed plan, conclusions where are determined in a summarized way if the validated processes are under control, the more relevant results, as well as how

  17. Validation of a 4D-PET Maximum Intensity Projection for Delineation of an Internal Target Volume

    International Nuclear Information System (INIS)

    Callahan, Jason; Kron, Tomas; Schneider-Kolsky, Michal; Dunn, Leon; Thompson, Mick; Siva, Shankar; Aarons, Yolanda; Binns, David; Hicks, Rodney J.

    2013-01-01

    Purpose: The delineation of internal target volumes (ITVs) in radiation therapy of lung tumors is currently performed by use of either free-breathing (FB) 18 F-fluorodeoxyglucose-positron emission tomography-computed tomography (FDG-PET/CT) or 4-dimensional (4D)-CT maximum intensity projection (MIP). In this report we validate the use of 4D-PET-MIP for the delineation of target volumes in both a phantom and in patients. Methods and Materials: A phantom with 3 hollow spheres was prepared surrounded by air then water. The spheres and water background were filled with a mixture of 18 F and radiographic contrast medium. A 4D-PET/CT scan was performed of the phantom while moving in 4 different breathing patterns using a programmable motion device. Nine patients with an FDG-avid lung tumor who underwent FB and 4D-PET/CT and >5 mm of tumor motion were included for analysis. The 3 spheres and patient lesions were contoured by 2 contouring methods (40% of maximum and PET edge) on the FB-PET, FB-CT, 4D-PET, 4D-PET-MIP, and 4D-CT-MIP. The concordance between the different contoured volumes was calculated using a Dice coefficient (DC). The difference in lung tumor volumes between FB-PET and 4D-PET volumes was also measured. Results: The average DC in the phantom using 40% and PET edge, respectively, was lowest for FB-PET/CT (DCAir = 0.72/0.67, DCBackground 0.63/0.62) and highest for 4D-PET/CT-MIP (DCAir = 0.84/0.83, DCBackground = 0.78/0.73). The average DC in the 9 patients using 40% and PET edge, respectively, was also lowest for FB-PET/CT (DC = 0.45/0.44) and highest for 4D-PET/CT-MIP (DC = 0.72/0.73). In the 9 lesions, the target volumes of the FB-PET using 40% and PET edge, respectively, were on average 40% and 45% smaller than the 4D-PET-MIP. Conclusion: A 4D-PET-MIP produces volumes with the highest concordance with 4D-CT-MIP across multiple breathing patterns and lesion sizes in both a phantom and among patients. Freebreathing PET/CT consistently underestimates ITV

  18. Validation of a 4D-PET Maximum Intensity Projection for Delineation of an Internal Target Volume

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, Jason, E-mail: jason.callahan@petermac.org [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Kron, Tomas [Department of Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne (Australia); Schneider-Kolsky, Michal [Department of Medical Imaging and Radiation Science, Monash University, Clayton, Victoria (Australia); Dunn, Leon [Department of Applied Physics, RMIT University, Melbourne (Australia); Thompson, Mick [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Siva, Shankar [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Aarons, Yolanda [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne (Australia); Binns, David [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Hicks, Rodney J. [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne (Australia)

    2013-07-15

    Purpose: The delineation of internal target volumes (ITVs) in radiation therapy of lung tumors is currently performed by use of either free-breathing (FB) {sup 18}F-fluorodeoxyglucose-positron emission tomography-computed tomography (FDG-PET/CT) or 4-dimensional (4D)-CT maximum intensity projection (MIP). In this report we validate the use of 4D-PET-MIP for the delineation of target volumes in both a phantom and in patients. Methods and Materials: A phantom with 3 hollow spheres was prepared surrounded by air then water. The spheres and water background were filled with a mixture of {sup 18}F and radiographic contrast medium. A 4D-PET/CT scan was performed of the phantom while moving in 4 different breathing patterns using a programmable motion device. Nine patients with an FDG-avid lung tumor who underwent FB and 4D-PET/CT and >5 mm of tumor motion were included for analysis. The 3 spheres and patient lesions were contoured by 2 contouring methods (40% of maximum and PET edge) on the FB-PET, FB-CT, 4D-PET, 4D-PET-MIP, and 4D-CT-MIP. The concordance between the different contoured volumes was calculated using a Dice coefficient (DC). The difference in lung tumor volumes between FB-PET and 4D-PET volumes was also measured. Results: The average DC in the phantom using 40% and PET edge, respectively, was lowest for FB-PET/CT (DCAir = 0.72/0.67, DCBackground 0.63/0.62) and highest for 4D-PET/CT-MIP (DCAir = 0.84/0.83, DCBackground = 0.78/0.73). The average DC in the 9 patients using 40% and PET edge, respectively, was also lowest for FB-PET/CT (DC = 0.45/0.44) and highest for 4D-PET/CT-MIP (DC = 0.72/0.73). In the 9 lesions, the target volumes of the FB-PET using 40% and PET edge, respectively, were on average 40% and 45% smaller than the 4D-PET-MIP. Conclusion: A 4D-PET-MIP produces volumes with the highest concordance with 4D-CT-MIP across multiple breathing patterns and lesion sizes in both a phantom and among patients. Freebreathing PET/CT consistently

  19. Societal Planning: Identifying a New Role for the Transport Planner-Part II: Planning Guidelines

    DEFF Research Database (Denmark)

    Khisty, C. Jotin; Leleur, Steen

    1997-01-01

    The paper seeks to formulate planning guidelines based on Habermas's theory of communicative action. Specifically, this has led to the formulation of a set of four planning validity claims concerned to four types of planning guidelines concerning adequacy, dependency, suitability and adaptability......-a-vis the planning validity claims. Among other things the contingency of this process is outlined. It is concluded (part I & II) that transport planners can conveniently utilize the guidelines in their professional practice, tailored to their particular settings....

  20. STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment Science and Operations Plan

    Energy Technology Data Exchange (ETDEWEB)

    Mace, J; Matrosov, S; Shupe, M; Lawson, P; Hallar, G; McCubbin, I; Marchand, R; Orr, B; Coulter, R; Sedlacek, A; Avallone, L; Long, C

    2010-09-29

    During the Storm Peak Lab Cloud Property Validation Experiment (STORMVEX), a substantial correlative data set of remote sensing observations and direct in situ measurements from fixed and airborne platforms will be created in a winter season, mountainous environment. This will be accomplished by combining mountaintop observations at Storm Peak Laboratory and the airborne National Science Foundation-supported Colorado Airborne Multi-Phase Cloud Study campaign with collocated measurements from the second ARM Mobile Facility (AMF2). We describe in this document the operational plans and motivating science for this experiment, which includes deployment of AMF2 to Steamboat Springs, Colorado. The intensive STORMVEX field phase will begin nominally on 1 November 2010 and extend to approximately early April 2011.

  1. Advantages of three-dimensional treatment planning in radiation therapy

    International Nuclear Information System (INIS)

    Attalla, E.M.; ELSAyed, A.A.; ElGantiry, M.; ElTahher, Z.

    2003-01-01

    This study was designed to demonstrate the feasibility of three-dimensional (3-D) treatment planning in-patients maxilla, breast, bladder, and lung tumors to explore its potential therapeutic advantage over the traditional dimensional (2-D) approach in these diseases. Conventional two-dimensional (2-D) treatment planning was compared to three-dimensional (3-D) treatment planning. In five selected disease sites, plans calculated with both types of treatment planning were compared. The (3-D) treatment planning system used in this work TMS version 5.1 B from helax AB is based on a monte Carlo-based pencil beam model. The other treatment planning system (2-D 0, introduced in this study was the multi data treatment planning system version 2.35. For the volumes of interest; quality of dose distribution concerning homogeneity in the target volume and the isodose distribution in organs at risk, was discussed. Qualitative and quantitative comparisons between the two planning systems were made using dose volume histograms (DVH's) . For comparisons of dose distributions in real-patient cases, differences ranged from 0.8% to 6.4% for 6 MV, while in case of 18 MV photon, it ranged from 1,8% to 6.5% and was within -+3 standard deviations for the dose between the two planning systems.Dose volume histogram (DVH) shows volume reduction of the radiation-related organs at risk 3-D planning

  2. Validation study of an interpolation method for calculating whole lung volumes and masses from reduced numbers of CT-images in ponies.

    Science.gov (United States)

    Reich, H; Moens, Y; Braun, C; Kneissl, S; Noreikat, K; Reske, A

    2014-12-01

    Quantitative computer tomographic analysis (qCTA) is an accurate but time intensive method used to quantify volume, mass and aeration of the lungs. The aim of this study was to validate a time efficient interpolation technique for application of qCTA in ponies. Forty-one thoracic computer tomographic (CT) scans obtained from eight anaesthetised ponies positioned in dorsal recumbency were included. Total lung volume and mass and their distribution into four compartments (non-aerated, poorly aerated, normally aerated and hyperaerated; defined based on the attenuation in Hounsfield Units) were determined for the entire lung from all 5 mm thick CT-images, 59 (55-66) per animal. An interpolation technique validated for use in humans was then applied to calculate qCTA results for lung volumes and masses from only 10, 12, and 14 selected CT-images per scan. The time required for both procedures was recorded. Results were compared statistically using the Bland-Altman approach. The bias ± 2 SD for total lung volume calculated from interpolation of 10, 12, and 14 CT-images was -1.2 ± 5.8%, 0.1 ± 3.5%, and 0.0 ± 2.5%, respectively. The corresponding results for total lung mass were -1.1 ± 5.9%, 0.0 ± 3.5%, and 0.0 ± 3.0%. The average time for analysis of one thoracic CT-scan using the interpolation method was 1.5-2 h compared to 8 h for analysis of all images of one complete thoracic CT-scan. The calculation of pulmonary qCTA data by interpolation from 12 CT-images was applicable for equine lung CT-scans and reduced the time required for analysis by 75%. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Dose distribution assessment (comparison) in the target volume treated with VMAT given by the planning system and evaluated by TL dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Bravim, A.; Sakuraba, R.K.; Campos, L.L., E-mail: ambravim@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Gerencia de Metrologia das Radiacoes

    2015-07-01

    Volumetric-modulated arc therapy (VMAT) is a relatively new therapy technique in which treatment is delivered using a cone beam that rotates around the patient. The radiation is delivered in a continuous gantry rotation while the cone beam is modulated by the intertwining of dynamic multileaf collimators (MLCs). Studies of VMAT plans have shown reduction in the treatment delivery time and monitor units (MU) comparable to IMRT plans improving major comfort to the patient and reducing uncertainties associated with patient movement during treatment. The treatment using VMAT minimizes the biological effects of radiation to critical structures near to the target volumes and produces excellent dose distributions. The dosimetry of ionizing radiation is essential for the radiological protection programs for quality assurance and licensing of equipment. For radiation oncology a quality assurance program is essentially to maintain the quality of patient care. As the VMAT is a new technique of radiation therapy it is important to optimize quality assurance mechanisms to ensure that tests are performed in order to preserve the patient and the equipment. This paper aims to determinate the dose distribution in the target volume (tumor to be treated) and the scattered dose distribution in the risk organs for VMAT technique comparing data given by the planning system and thermoluminescent (TL) response. (author)

  4. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) verification and validation plan. version 1.

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, Roscoe Ainsworth; Arguello, Jose Guadalupe, Jr.; Urbina, Angel; Bouchard, Julie F.; Edwards, Harold Carter; Freeze, Geoffrey A.; Knupp, Patrick Michael; Wang, Yifeng; Schultz, Peter Andrew; Howard, Robert (Oak Ridge National Laboratory, Oak Ridge, TN); McCornack, Marjorie Turner

    2011-01-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. To meet this objective, NEAMS Waste IPSC M&S capabilities will be applied to challenging spatial domains, temporal domains, multiphysics couplings, and multiscale couplings. A strategic verification and validation (V&V) goal is to establish evidence-based metrics for the level of confidence in M&S codes and capabilities. Because it is economically impractical to apply the maximum V&V rigor to each and every M&S capability, M&S capabilities will be ranked for their impact on the performance assessments of various components of the repository systems. Those M&S capabilities with greater impact will require a greater level of confidence and a correspondingly greater investment in V&V. This report includes five major components: (1) a background summary of the NEAMS Waste IPSC to emphasize M&S challenges; (2) the conceptual foundation for verification, validation, and confidence assessment of NEAMS Waste IPSC M&S capabilities; (3) specifications for the planned verification, validation, and confidence-assessment practices; (4) specifications for the planned evidence information management system; and (5) a path forward for the incremental implementation of this V&V plan.

  5. Functional avoidance of lung in plan optimization with an aperture-based inverse planning system

    International Nuclear Information System (INIS)

    St-Hilaire, Jason; Lavoie, Caroline; Dagnault, Anne; Beaulieu, Frederic; Morin, Francis; Beaulieu, Luc; Tremblay, Daniel

    2011-01-01

    Purpose: To implement SPECT-based optimization in an anatomy-based aperture inverse planning system for the functional avoidance of lung in thoracic irradiation. Material and methods: SPECT information has been introduced as a voxel-by-voxel modulation of lung importance factors proportionally to the local perfusion count. Fifteen cases of lung cancer have been retrospectively analyzed by generating angle-optimized non-coplanar plans, comparing a purely anatomical approach and our functional approach. Planning target volume coverage and lung sparing have been compared. Statistical significance was assessed by a Wilcoxon matched pairs test. Results: For similar target coverage, perfusion-weighted volume receiving 10 Gy was reduced by a median of 2.2% (p = 0.022) and mean perfusion-weighted lung dose, by a median of 0.9 Gy (p = 0.001). A separate analysis of patients with localized or non-uniform hypoperfusion could not show which would benefit more from SPECT-based treatment planning. Redirection of dose sometimes created overdosage regions in the target volume. Plans consisted of a similar number of segments and monitor units. Conclusions: Angle optimization and SPECT-based modulation of importance factors allowed for functional avoidance of the lung while preserving target coverage. The technique could be also applied to implement PET-based modulation inside the target volume, leading to a safer dose escalation.

  6. Agent independent task planning

    Science.gov (United States)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  7. Transcranial sonography: integration into target volume definition for glioblastoma multiforme

    International Nuclear Information System (INIS)

    Vordermark, Dirk; Becker, Georg; Flentje, Michael; Richter, Susanne; Goerttler-Krauspe, Irene; Koelbl, Oliver

    2000-01-01

    Purpose: Recent studies indicate that transcranial sonography (TCS) reliably displays the extension of malignant brain tumors. The effect of integrating TCS into radiotherapy planning for glioblastoma multiforme (GBM) was investigated herein. Methods and Materials: Thirteen patients subtotally resected for GBM underwent TCS during radiotherapy planning and were conventionally treated (54 to 60 Gy). Gross tumor volumes (GTVs) and stereotactic boost planning target volumes (PTVs, 3-mm margin) were created, based on contrast enhancement on computed tomography (CT) only (PTV CT ) or the combined CT and TCS information (PTV CT+TCS ). Noncoplonar conformal treatment plans for both PTVs were compared. Tumor progression patterns and preoperative magnetic resonance imaging (MRI) were related to both PTVs. Results: A sufficient temporal bone window for TCS was present in 11 of 13 patients. GTVs as defined by TCS were considerably larger than the respective CT volumes: Of the composite GTV CT+TCS (median volume 42 ml), 23%, 13%, and 66% (medians) were covered by the overlap of both methods, CT only and TCS only, respectively. Median sizes of PTV CT and PTV CT+TCS were 34 and 74 ml, respectively. Addition of TCS to CT information led to a median increase of the volume irradiated within the 80% isodose by 32 ml (median factor 1.51). PTV CT+TCS volume was at median 24% of a 'conventional' MRI(T2)-based PTV. Of eight progressions analyzed, three and six occurred inside the 80% isodose of the plans for PTV CT and for PTV CT+TCS , respectively. Conclusion: Addition of TCS tumor volume to the contrast-enhancing CT volume in postoperative radiotherapy planning for GBM increases the treated volume by a median factor of 1.5. Since a high frequency of marginal recurrences is reported from dose-escalation trials of this disease, TCS may complement established methods in PTV definition

  8. SU-F-J-105: Towards a Novel Treatment Planning Pipeline Delivering Pareto- Optimal Plans While Enabling Inter- and Intrafraction Plan Adaptation

    Energy Technology Data Exchange (ETDEWEB)

    Kontaxis, C; Bol, G; Lagendijk, J; Raaymakers, B [University Medical Center Utrecht, Utrecht (Netherlands); Breedveld, S; Sharfo, A; Heijmen, B [Erasmus University Medical Center Rotterdam, Rotterdam (Netherlands)

    2016-06-15

    Purpose: To develop a new IMRT treatment planning methodology suitable for the new generation of MR-linear accelerator machines. The pipeline is able to deliver Pareto-optimal plans and can be utilized for conventional treatments as well as for inter- and intrafraction plan adaptation based on real-time MR-data. Methods: A Pareto-optimal plan is generated using the automated multicriterial optimization approach Erasmus-iCycle. The resulting dose distribution is used as input to the second part of the pipeline, an iterative process which generates deliverable segments that target the latest anatomical state and gradually converges to the prescribed dose. This process continues until a certain percentage of the dose has been delivered. Under a conventional treatment, a Segment Weight Optimization (SWO) is then performed to ensure convergence to the prescribed dose. In the case of inter- and intrafraction adaptation, post-processing steps like SWO cannot be employed due to the changing anatomy. This is instead addressed by transferring the missing/excess dose to the input of the subsequent fraction. In this work, the resulting plans were delivered on a Delta4 phantom as a final Quality Assurance test. Results: A conventional static SWO IMRT plan was generated for two prostate cases. The sequencer faithfully reproduced the input dose for all volumes of interest. For the two cases the mean relative dose difference of the PTV between the ideal input and sequenced dose was 0.1% and −0.02% respectively. Both plans were delivered on a Delta4 phantom and passed the clinical Quality Assurance procedures by achieving 100% pass rate at a 3%/3mm gamma analysis. Conclusion: We have developed a new sequencing methodology capable of online plan adaptation. In this work, we extended the pipeline to support Pareto-optimal input and clinically validated that it can accurately achieve these ideal distributions, while its flexible design enables inter- and intrafraction plan

  9. SU-F-J-105: Towards a Novel Treatment Planning Pipeline Delivering Pareto- Optimal Plans While Enabling Inter- and Intrafraction Plan Adaptation

    International Nuclear Information System (INIS)

    Kontaxis, C; Bol, G; Lagendijk, J; Raaymakers, B; Breedveld, S; Sharfo, A; Heijmen, B

    2016-01-01

    Purpose: To develop a new IMRT treatment planning methodology suitable for the new generation of MR-linear accelerator machines. The pipeline is able to deliver Pareto-optimal plans and can be utilized for conventional treatments as well as for inter- and intrafraction plan adaptation based on real-time MR-data. Methods: A Pareto-optimal plan is generated using the automated multicriterial optimization approach Erasmus-iCycle. The resulting dose distribution is used as input to the second part of the pipeline, an iterative process which generates deliverable segments that target the latest anatomical state and gradually converges to the prescribed dose. This process continues until a certain percentage of the dose has been delivered. Under a conventional treatment, a Segment Weight Optimization (SWO) is then performed to ensure convergence to the prescribed dose. In the case of inter- and intrafraction adaptation, post-processing steps like SWO cannot be employed due to the changing anatomy. This is instead addressed by transferring the missing/excess dose to the input of the subsequent fraction. In this work, the resulting plans were delivered on a Delta4 phantom as a final Quality Assurance test. Results: A conventional static SWO IMRT plan was generated for two prostate cases. The sequencer faithfully reproduced the input dose for all volumes of interest. For the two cases the mean relative dose difference of the PTV between the ideal input and sequenced dose was 0.1% and −0.02% respectively. Both plans were delivered on a Delta4 phantom and passed the clinical Quality Assurance procedures by achieving 100% pass rate at a 3%/3mm gamma analysis. Conclusion: We have developed a new sequencing methodology capable of online plan adaptation. In this work, we extended the pipeline to support Pareto-optimal input and clinically validated that it can accurately achieve these ideal distributions, while its flexible design enables inter- and intrafraction plan

  10. Treatment planning for a small animal using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Chow, James C. L.; Leung, Michael K. K.

    2007-01-01

    The development of a small animal model for radiotherapy research requires a complete setup of customized imaging equipment, irradiators, and planning software that matches the sizes of the subjects. The purpose of this study is to develop and demonstrate the use of a flexible in-house research environment for treatment planning on small animals. The software package, called DOSCTP, provides a user-friendly platform for DICOM computed tomography-based Monte Carlo dose calculation using the EGSnrcMP-based DOSXYZnrc code. Validation of the treatment planning was performed by comparing the dose distributions for simple photon beam geometries calculated through the Pinnacle3 treatment planning system and measurements. A treatment plan for a mouse based on a CT image set by a 360-deg photon arc is demonstrated. It is shown that it is possible to create 3D conformal treatment plans for small animals with consideration of inhomogeneities using small photon beam field sizes in the diameter range of 0.5-5 cm, with conformal dose covering the target volume while sparing the surrounding critical tissue. It is also found that Monte Carlo simulation is suitable to carry out treatment planning dose calculation for small animal anatomy with voxel size about one order of magnitude smaller than that of the human

  11. MRI-assisted versus conventional treatment planning in brachytherapy of cervical and endometrial carcinoma: The impact of individual anatomy on dose distribution in target volume and organs at risk

    International Nuclear Information System (INIS)

    Wulf, Joern; Sauer, Otto A.; Herbolsheimer, Michael; Oppitz, Ulrich; Flentje, Michael

    1996-01-01

    Objective: Dose prescription and definition of target volume in brachytherapy of cervical and endometrial cancer are calculated to standard points as Manchester point A or point My(ometrium) in most centers. Calculation of doses to organs at risk mainly relies on ICRU-report 38. But standard dose prescription neglects individual patient anatomy. While MRI and CT had widespread impact on individual planning in external beam radiotherapy, there is still a minor influence on brachytherapy. The impact of individual anatomy on dose distribution in target volume and organs at risk demonstrates the objective of individual brachytherapy planning. Materials and Methods: 8 patients with cervical and 4 patients with endometrial carcinoma underwent MRI of the pelvis with in-situ applicators (ring-tandem applicators for cervical carcinoma and modified Heyman-capsules for endometrial carcinoma). T1w slices were angulated coronal and sagittal to get rectangular reproductions to applicator axis. Orthogonal or isocentric X-ray films for conventional treatment planning were done. MRI-information on target and organs at risk was transformed into coordinates relative to applicator axis and dose calculation on the database of conventional treatment planning was performed by Nucletron Planning System PLATO. Isodoses were projected into MRI slices. Prescribed dose to patients with cervical cancer was 8.5 Gy to point A resp. 10 Gy to point My (2cm below fundal myometrium and 2cm lateral applicator axis) in endometrial cancer. Results: Dose prescription to Manchester point A or point My represented in only 50% of cases uterine serosa. Instead of 2cm lateral of applicator axis, uterine surface ranged from 1.0 cm to 3.9 cm at the level of point A (mean 2.25 cm coronal and 1.77 cm sagittal) and from 1.5 cm to 4.4 cm at the level of point My (mean 2.7 cm coronal and 2.1 cm sagittal). Uterine volume ranged from 69 cc to 277 cc, mean volume was 150cc. Dose-volume histograms of patients with

  12. Inverse planning for interstitial gynecologic template brachytherapy: truly anatomy-based planning

    International Nuclear Information System (INIS)

    Lessard, Etienne; Hsu, I-Chou; Pouliot, Jean

    2002-01-01

    Purpose: Commercially available optimization schemes generally result in an undesirable dose distribution, because of the particular shapes of tumors extending laterally from the tandem. Dose distribution is therefore manually obtained by adjusting relative dwell time values until an acceptable solution is found. The objective of this work is to present the clinical application of an inverse planning dose optimization tool for the automatic determination of source dwell time values in the treatment of interstitial gynecologic templates. Methods and Materials: In cases where the tumor extends beyond the range of the tandem-ovoid applicator, catheters as well as the tandem are inserted into the paravaginal and parametrial region in an attempt to cover the tumor volume. CT scans of these patients are then used for CT-based dose planning. Dose distribution is obtained manually by varying the relative dwell times until adequate dose coverage is achieved. This manual planning is performed by an experienced physician. In parallel, our in-house inverse planning based on simulated annealing is used to automatically determine which of all possible dwell positions will become active and to calculate the dwell time values needed to fulfill dose constraints applied to the tumor volume and to each organ at risk. To compare the results of these planning methods, dose-volume histograms and isodose distributions were generated for the target and each organ at risk. Results: This procedure has been applied for the dose planning of 12 consecutive interstitial gynecologic templates cases. For all cases, once the anatomy was contoured, the routine of inverse planning based on simulated annealing found the solution to the dose constraints within 1 min of CPU time. In comparison, manual planning took more than 45 min. The inverse planning-generated plans showed improved protection to organs at risk for the same coverage compared to manual planning. Conclusion: This inverse planning tool

  13. Validation of the Simbionix PROcedure Rehearsal Studio sizing module : A comparison of software for endovascular aneurysm repair sizing and planning

    NARCIS (Netherlands)

    Velu, Juliëtte F.; Groot Jebbink, Erik; de Vries, Jean-Paul P.M.; Slump, Cornelis H.; Geelkerken, Robert H.

    2017-01-01

    An important determinant of successful endovascular aortic aneurysm repair is proper sizing of the dimensions of the aortic-iliac vessels. The goal of the present study was to determine the concurrent validity, a method for comparison of test scores, for EVAR sizing and planning of the recently

  14. Dosimetric improvements following 3D planning of tangential breast irradiation

    International Nuclear Information System (INIS)

    Aref, Amr; Thornton, Dale; Youssef, Emad; He, Tony; Tekyi-Mensah, Samuel; Denton, Lori; Ezzell, Gary

    2000-01-01

    Purpose: To evaluate the dosimetric difference between a simple radiation therapy plan utilizing a single contour and a more complex three-dimensional (3D) plan utilizing multiple contours, lung inhomogeneity correction, and dose-based compensators. Methods and Materials: This is a study of the radiation therapy (RT) plans of 85 patients with early breast cancer. All patients were considered for breast-conserving management and treated by conventional tangential fields technique. Two plans were generated for each patient. The first RT plan was based on a single contour taken at the central axis and utilized two wedges. The second RT plan was generated by using the 3D planning system to design dose-based compensators after lung inhomogeneity correction had been made. The endpoints of the study were the comparison between the volumes receiving greater than 105% and greater than 110% of the reference dose, as well as the magnitude of the treated volume maximum dose. Dosimetric improvement was defined to be of significant value if the volume receiving > 105% of one plan was reduced by at least 50% with the absolute difference between the volumes being 5% or greater. The dosimetric improvements in 49 3D plans (58%) were considered of significant value. Patients' field separation and breast size did not predict the magnitude of improvement in dosimetry. Conclusion: Dose-based compensator plans significantly reduced the volumes receiving > 105%, >110%, and volume maximum dose.

  15. Evaluation of IMRT plans of prostate carcinoma from four treatment planning systems based on Monte Carlo

    International Nuclear Information System (INIS)

    Chi Zifeng; Han Chun; Liu Dan; Cao Yankun; Li Runxiao

    2011-01-01

    Objective: With the Monte Carlo method to recalculate the IMRT dose distributions from four TPS to provide a platform for independent comparison and evaluation of the plan quality.These results will help make a clinical decision as which TPS will be used for prostate IMRT planning. Methods: Eleven prostate cancer cases were planned with the Corvus, Xio, Pinnacle and Eclipse TPS. The plans were recalculated by Monte Carlo using leaf sequences and MUs for individual plans. Dose-volume-histograms and isodose distributions were compared. Other quantities such as D min (the minimum dose received by 99% of CTV/PTV), D max (the maximum dose received by 1% of CTV/PTV), V 110% , V 105% , V 95% (the volume of CTV/PTV receiving 110%, 105%, 95% of the prescription dose), the volume of rectum and bladder receiving >65 Gy and >40 Gy, and the volume of femur receiving >50 Gy were evaluated. Total segments and MUs were also compared. Results: The Monte Carlo results agreed with the dose distributions from the TPS to within 3%/3 mm. The Xio, Pinnacle and Eclipse plans show less target dose heterogeneity and lower V 65 and V 40 for the rectum and bladder compared to the Corvus plans. The PTV D min is about 2 Gy lower for Xio plans than others while the Corvus plans have slightly lower female head V 50 (0.03% and 0.58%) than others. The Corvus plans require significantly most segments (187.8) and MUs (1264.7) to deliver and the Pinnacle plans require fewest segments (82.4) and MUs (703.6). Conclusions: We have tested an independent Monte Carlo dose calculation system for dose reconstruction and plan evaluation. This system provides a platform for the fair comparison and evaluation of treatment plans to facilitate clinical decision making in selecting a TPS and beam delivery system for particular treatment sites. (authors)

  16. Clinical trials radiotherapy treatment plan review software : is this the first quantified assessment

    International Nuclear Information System (INIS)

    Hatton, J.A.; Cornes, D.A.

    2011-01-01

    Full text: Clinical trials require robust quality assurance (QA) procedures to ensure commonality of all treatments, with independent reviews to assess compliance with trial protocols. All clinical trials tools, including QA software, require testing for validity and reliability. enabling inter- and intra-trial comparison. Unlike clinical radiotherapy treatment planning (RTP) systems, review software has no published guidelines. This study describes the design and development of a test suite to quantify the performance of review software in TROG clinical trials. Test areas are image handling and reconstruction; geometric accuracy; dosimetric accuracy; dose-volume histogram (DVH) calculation; display of plan parameters. TROG have developed tests for commissioning plan review software, assessed with SWAN 2.3, and CMS Elekta FocalPro. While image handling tests were based on published guidelines for RTP systems, dosimetric tests used the TROG QA case review requirements. Treatment plans represented systems of all manufacturers (Pinnacle, Eclipse, Xio and Oncentra) used in Australasian centres. The test suite identified areas for SW A software development, including the DVH algorithm, changed to reduce calculation time. Results, in Fig. I, for known volumes of varying shapes and sizes, demonstrate differences between SWAN 2.1 and 2.3 when compared with Eclipse. Liaison with SWAN programmers enabled re-instatement of 2.1 algorithm. The test suite has quantified the RTP review software, prioritised areas for development with the programmers, and improved the user experience.

  17. Using SysML for verification and validation planning on the Large Synoptic Survey Telescope (LSST)

    Science.gov (United States)

    Selvy, Brian M.; Claver, Charles; Angeli, George

    2014-08-01

    This paper provides an overview of the tool, language, and methodology used for Verification and Validation Planning on the Large Synoptic Survey Telescope (LSST) Project. LSST has implemented a Model Based Systems Engineering (MBSE) approach as a means of defining all systems engineering planning and definition activities that have historically been captured in paper documents. Specifically, LSST has adopted the Systems Modeling Language (SysML) standard and is utilizing a software tool called Enterprise Architect, developed by Sparx Systems. Much of the historical use of SysML has focused on the early phases of the project life cycle. Our approach is to extend the advantages of MBSE into later stages of the construction project. This paper details the methodology employed to use the tool to document the verification planning phases, including the extension of the language to accommodate the project's needs. The process includes defining the Verification Plan for each requirement, which in turn consists of a Verification Requirement, Success Criteria, Verification Method(s), Verification Level, and Verification Owner. Each Verification Method for each Requirement is defined as a Verification Activity and mapped into Verification Events, which are collections of activities that can be executed concurrently in an efficient and complementary way. Verification Event dependency and sequences are modeled using Activity Diagrams. The methodology employed also ties in to the Project Management Control System (PMCS), which utilizes Primavera P6 software, mapping each Verification Activity as a step in a planned activity. This approach leads to full traceability from initial Requirement to scheduled, costed, and resource loaded PMCS task-based activities, ensuring all requirements will be verified.

  18. Federal Facilities Compliance Act, Draft Site Treatment Plan: Background Volume, Part 2, Volume 1

    International Nuclear Information System (INIS)

    1994-01-01

    This Draft Site Treatment Plan was prepared by Ames Laboratory to meet the requirements of the Federal Facilities Compliance Act. Topics discussed include: purpose and scope of the plan; site history and mission; draft plant organization; waste minimization; waste characterization; preferred option selection process; technology for treating low-level radioactive wastes and TRU wastes; future generation of mixed waste streams; funding; and process for evaluating disposal issues in support of the site treatment plan

  19. Implementation of the validation testing in MPPG 5.a "Commissioning and QA of treatment planning dose calculations-megavoltage photon and electron beams".

    Science.gov (United States)

    Jacqmin, Dustin J; Bredfeldt, Jeremy S; Frigo, Sean P; Smilowitz, Jennifer B

    2017-01-01

    The AAPM Medical Physics Practice Guideline (MPPG) 5.a provides concise guidance on the commissioning and QA of beam modeling and dose calculation in radiotherapy treatment planning systems. This work discusses the implementation of the validation testing recommended in MPPG 5.a at two institutions. The two institutions worked collaboratively to create a common set of treatment fields and analysis tools to deliver and analyze the validation tests. This included the development of a novel, open-source software tool to compare scanning water tank measurements to 3D DICOM-RT Dose distributions. Dose calculation algorithms in both Pinnacle and Eclipse were tested with MPPG 5.a to validate the modeling of Varian TrueBeam linear accelerators. The validation process resulted in more than 200 water tank scans and more than 50 point measurements per institution, each of which was compared to a dose calculation from the institution's treatment planning system (TPS). Overall, the validation testing recommended in MPPG 5.a took approximately 79 person-hours for a machine with four photon and five electron energies for a single TPS. Of the 79 person-hours, 26 person-hours required time on the machine, and the remainder involved preparation and analysis. The basic photon, electron, and heterogeneity correction tests were evaluated with the tolerances in MPPG 5.a, and the tolerances were met for all tests. The MPPG 5.a evaluation criteria were used to assess the small field and IMRT/VMAT validation tests. Both institutions found the use of MPPG 5.a to be a valuable resource during the commissioning process. The validation testing in MPPG 5.a showed the strengths and limitations of the TPS models. In addition, the data collected during the validation testing is useful for routine QA of the TPS, validation of software upgrades, and commissioning of new algorithms. © 2016 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of

  20. Validitas Lesson Plan Berbasis Multiple Intelligences untuk Pembelajaran Matematika

    Directory of Open Access Journals (Sweden)

    Vigih Hery Kristanto

    2017-12-01

    Full Text Available The purpose of this research is to know the validity of Lesson Plan based on multiple intelligences for learning mathematics in junior high school students. This research is a simple research with qualitative type. The validity of Lesson Plan is seen through two aspects, namely the linguistic aspect and the substance (content aspect. Thus, the instrument used in this research is the Linguistic Aspects Validation Guidance and the Substance Validation Guidelines (contents Guidance. Validation is done by two validators Lingusitic expert field and Mathematics expert field. The results showed that the validity of linguistic aspects of 3.35 and the validity of the substance (content of 3.82, so it can be concluded Lesson Plan based multiple intelligences for learning mathematics in junior high school students who have been compiled valid based on the language aspect. In addition, Lesson Plan based multiple intelligences for learning mathematics in junior high school students who have been compiled valid based on aspects of substance (content.

  1. Investigations on the quality of manual image segmentation in 3D radiotherapy planning

    International Nuclear Information System (INIS)

    Perelmouter, J.; Tuebingen Univ.; Bohsung, J.; Nuesslin, F.; Becker, G.; Kortmann, R.D.; Bamberg, M.

    1998-01-01

    In 3D radiotherapy planning image segmentation plays an important role in the definition process of target volume and organs at risk. Here, we present a method to quantify the technical precision of the manual image segmentation process. To validate our method we developed a virtual phantom consisting of several geometrical objects of changing form and contrast, which should be contoured by volunteers using the TOMAS tool for manual segmentation of the Heidelberg VOXELPLAN system. The results of this examination are presented. (orig.) [de

  2. MELSAR: a mesoscale air quality model for complex terrain. Volume 2. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K.J.; Whiteman, C.D.

    1985-04-01

    This final report is submitted as part of the Green River Ambient Model Assessment (GRAMA) project conducted at the US Department of Energy's Pacific Northwest Laboratory for the US Environmental Protection Agency. The GRAMA Program has, as its ultimate goal, the development of validated air quality models that can be applied to the complex terrain of the Green River Formation of western Colorado, eastern Utah and southern Wyoming. The Green River Formation is a geologic formation containing large reserves of oil shale, coal, and other natural resources. Development of these resources may lead to a degradation of the air quality of the region. Air quality models are needed immediately for planning and regulatory purposes to assess the magnitude of these regional impacts. This report documents one of the models being developed for this purpose within GRAMA - specifically a model to predict short averaging time (less than or equal to 24 h) pollutant concentrations resulting from the mesoscale transport of pollutant releases from multiple sources. MELSAR has not undergone any rigorous operational testing, sensitivity analyses, or validation studies. Testing and evaluation of the model are needed to gain a measure of confidence in the model's performance. This report consists of two volumes. This volume contains the Appendices, which include listings of the FORTRAN code and Volume 1 contains the model overview, technical description, and user's guide. 13 figs., 10 tabs.

  3. Waste Feed Delivery Planning at Hanford - 13232

    International Nuclear Information System (INIS)

    Certa, Paul J.; Hohl, Ted M.; Kelly, James W.; Larsen, Douglas C.; West, Elizha B.; Ritari, Jaakob S.; Rodriguez, Juissepp S.

    2013-01-01

    The Integrated Waste Feed Delivery Plan (IWFDP) describes how waste feed will be delivered to the Waste Treatment and Immobilization Plant (WTP) to safely and efficiently accomplish the River Protection Project (RPP) mission. The IWFDP, which is integrated with the Baseline Case operating scenario, is comprised of three volumes. Volume 1 - Process Strategy provides an overview of waste feed delivery (WFD) and describes how the WFD system will be used to prepare and deliver feed to the WTP based on the equipment configuration and functional capabilities of the WFD system. Volume 2 - Campaign Plan describes the plans for the first eight campaigns for delivery to the WTP, evaluates projected feed for systematic issues, projects 242-A Evaporator campaigns, and evaluates double-shell tank (DST) space and availability of contingency feed. Volume 3 - Project Plan identifies the scope and timing of the DST and infrastructure upgrade projects necessary to feed the WTP, and coordinates over 30 projectized projects and operational activities that comprise the needed WFD upgrades. (authors)

  4. Waste Feed Delivery Planning at Hanford - 13232

    Energy Technology Data Exchange (ETDEWEB)

    Certa, Paul J.; Hohl, Ted M.; Kelly, James W.; Larsen, Douglas C.; West, Elizha B.; Ritari, Jaakob S.; Rodriguez, Juissepp S. [Washington River Protection Solutions, LLC, P.O. 850, Richland, WA 99352 (United States)

    2013-07-01

    The Integrated Waste Feed Delivery Plan (IWFDP) describes how waste feed will be delivered to the Waste Treatment and Immobilization Plant (WTP) to safely and efficiently accomplish the River Protection Project (RPP) mission. The IWFDP, which is integrated with the Baseline Case operating scenario, is comprised of three volumes. Volume 1 - Process Strategy provides an overview of waste feed delivery (WFD) and describes how the WFD system will be used to prepare and deliver feed to the WTP based on the equipment configuration and functional capabilities of the WFD system. Volume 2 - Campaign Plan describes the plans for the first eight campaigns for delivery to the WTP, evaluates projected feed for systematic issues, projects 242-A Evaporator campaigns, and evaluates double-shell tank (DST) space and availability of contingency feed. Volume 3 - Project Plan identifies the scope and timing of the DST and infrastructure upgrade projects necessary to feed the WTP, and coordinates over 30 projectized projects and operational activities that comprise the needed WFD upgrades. (authors)

  5. Waste feed delivery planning at Hanford-13232

    International Nuclear Information System (INIS)

    Certa, Paul J.; West, Elizha B.; Rodriguez, Juissepp S.; Hohl, Ted M.; Larsen, Douglas C.; Ritari, Jaakob S.; Kelly, James W.

    2013-01-01

    The Integrated Waste Feed Delivery Plan (IWFDP) describes how waste feed will be delivered to the Waste Treatment and Immobilization Plant (WTP) to safely and efficiently accomplish the River Protection Project (RPP) mission. The IWFDP, which is integrated with the Baseline Case operating scenario, is comprised of three volumes. Volume 1 - Process Strategy provides an overview of waste feed delivery (WFD) and describes how the WFD system will be used to prepare and deliver feed to the WTP based on the equipment configuration and functional capabilities of the WFD system. Volume 2 - Campaign Plan describes the plans for the first eight campaigns for delivery to the WTP, evaluates projected feed for systematic issues, projects 242-A Evaporator campaigns, and evaluates double-shell tank (DST) space and availability of contingency feed. Volume 3 - Project Plan identifies the scope and timing of the DST and infrastructure upgrade projects necessary to feed the WTP, and coordinates over 30 projectized projects and operational activities that comprise the needed WFD upgrades

  6. Impact of database quality in knowledge-based treatment planning for prostate cancer.

    Science.gov (United States)

    Wall, Phillip D H; Carver, Robert L; Fontenot, Jonas D

    2018-03-13

    This article investigates dose-volume prediction improvements in a common knowledge-based planning (KBP) method using a Pareto plan database compared with using a conventional, clinical plan database. Two plan databases were created using retrospective, anonymized data of 124 volumetric modulated arc therapy (VMAT) prostate cancer patients. The clinical plan database (CPD) contained planning data from each patient's clinically treated VMAT plan, which were manually optimized by various planners. The multicriteria optimization database (MCOD) contained Pareto-optimal plan data from VMAT plans created using a standardized multicriteria optimization protocol. Overlap volume histograms, incorporating fractional organ at risk volumes only within the treatment fields, were computed for each patient and used to match new patient anatomy to similar database patients. For each database patient, CPD and MCOD KBP predictions were generated for D 10 , D 30 , D 50 , D 65 , and D 80 of the bladder and rectum in a leave-one-out manner. Prediction achievability was evaluated through a replanning study on a subset of 31 randomly selected database patients using the best KBP predictions, regardless of plan database origin, as planning goals. MCOD predictions were significantly lower than CPD predictions for all 5 bladder dose-volumes and rectum D 50 (P = .004) and D 65 (P databases affects the performance and achievability of dose-volume predictions from a common knowledge-based planning approach for prostate cancer. Bladder and rectum dose-volume predictions derived from a database of standardized Pareto-optimal plans were compared with those derived from clinical plans manually designed by various planners. Dose-volume predictions from the Pareto plan database were significantly lower overall than those from the clinical plan database, without compromising achievability. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. PlanJury: probabilistic plan evaluation revisited

    Science.gov (United States)

    Witte, M.; Sonke, J.-J.; van Herk, M.

    2014-03-01

    Purpose: Over a decade ago, the 'Van Herk margin recipe paper' introduced plan evaluation through DVH statistics based on population distributions of systematic and random errors. We extended this work for structures with correlated uncertainties (e.g. lymph nodes or parotid glands), and considered treatment plans containing multiple (overlapping) dose distributions (e.g. conventional lymph node and hypo-fractionated tumor doses) for which different image guidance protocols may lead to correlated errors. Methods: A command-line software tool 'PlanJury' was developed which reads 3D dose and structure data exported from a treatment planning system. Uncertainties are specified by standard deviations and correlation coefficients. Parameters control the DVH statistics to be computed: e.g. the probability of reaching a DVH constraint, or the dose absorbed at given confidence in a (combined) volume. Code was written in C++ and parallelized using OpenMP. Testing geometries were constructed using idealized spherical volumes and dose distributions. Results: Negligible stochastic noise could be attained within two minutes computation time for a single target. The confidence to properly cover both of two targets was 90% for two synchronously moving targets, but decreased by 7% if the targets moved independently. For two partially covered organs at risk the confidence of at least one organ below the mean dose threshold was 40% for synchronous motion, 36% for uncorrelated motion, but only 20% for either of the organs separately. Two abutting dose distributions ensuring 91% confidence of proper target dose for correlated motions led to 28% lower confidence for uncorrelated motions as relative displacements between the doses resulted in cold spots near the target. Conclusions: Probabilistic plan evaluation can efficiently be performed for complicated treatment planning situations, thus providing important plan quality information unavailable in conventional PTV based evaluations.

  8. TH-A-9A-08: Knowledge-Based Quality Control of Clinical Stereotactic Radiosurgery Treatment Plans

    International Nuclear Information System (INIS)

    Shiraishi, S; Moore, K L; Tan, J; Olsen, L

    2014-01-01

    Purpose: To develop a quality control tool to reduce stereotactic radiosurgery (SRS) planning variability using models that predict achievable plan quality metrics (QMs) based on individual patient anatomy. Methods: Using a knowledge-based methodology that quantitatively correlates anatomical geometric features to resultant organ-at-risk (OAR) dosimetry, we developed models for predicting achievable OAR dose-volume histograms (DVHs) by training with a cohort of previously treated SRS patients. The DVH-based QMs used in this work are the gradient measure, GM=(3/4pi)^1/3*[V50%^1/3−V100%^1/3], and V10Gy of normal brain. As GM quantifies the total rate of dose fall-off around the planning target volume (PTV), all voxels inside the patient's body contour were treated as OAR for DVH prediction. 35 previously treated SRS plans from our institution were collected; all were planned with non-coplanar volumetric-modulated arc therapy to prescription doses of 12–25 Gy. Of the 35-patient cohort, 15 were used for model training and 20 for model validation. Accuracies of the predictions were quantified by the mean and the standard deviation of the difference between clinical and predicted QMs, δQM=QM-clin−QM-pred. Results: Best agreement between predicted and clinical QMs was obtained when models were built separately for V-PTV<2.5cc and V-PTV>2.5cc. Eight patients trained the V-PTV<2.5cc model and seven patients trained the V-PTV>2.5cc models, respectively. The mean and the standard deviation of δGM were 0.3±0.4mm for the training sets and −0.1±0.6mm for the validation sets, demonstrating highly accurate GM predictions. V10Gy predictions were also highly accurate, with δV10Gy=0.8±0.7cc for the training sets and δV10Gy=0.7±1.4cc for the validation sets. Conclusion: The accuracy of the models in predicting two key SRS quality metrics highlights the potential of this technique for quality control for SRS treatments. Future investigations will seek to determine

  9. Spent Nuclear Fuel (SNF) Process Validation Technical Support Plan

    Energy Technology Data Exchange (ETDEWEB)

    SEXTON, R.A.

    2000-03-13

    The purpose of Process Validation is to confirm that nominal process operations are consistent with the expected process envelope. The Process Validation activities described in this document are not part of the safety basis, but are expected to demonstrate that the process operates well within the safety basis. Some adjustments to the process may be made as a result of information gathered in Process Validation.

  10. Spent Nuclear Fuel (SNF) Process Validation Technical Support Plan

    International Nuclear Information System (INIS)

    SEXTON, R.A.

    2000-01-01

    The purpose of Process Validation is to confirm that nominal process operations are consistent with the expected process envelope. The Process Validation activities described in this document are not part of the safety basis, but are expected to demonstrate that the process operates well within the safety basis. Some adjustments to the process may be made as a result of information gathered in Process Validation

  11. Behaviors in Advance Care Planning and ACtions Survey (BACPACS): development and validation part 1.

    Science.gov (United States)

    Kassam, Aliya; Douglas, Maureen L; Simon, Jessica; Cunningham, Shannon; Fassbender, Konrad; Shaw, Marta; Davison, Sara N

    2017-11-22

    Although advance care planning (ACP) is fairly well understood, significant barriers to patient participation remain. As a result, tools to assess patient behaviour are required. The objective of this study was to improve the measurement of patient engagement in ACP by detecting existing survey design issues and establishing content and response process validity for a new survey entitled Behaviours in Advance Care Planning and ACtions Survey (BACPACS). We based our new tool on that of an existing ACP engagement survey. Initial item reduction was carried out using behavior change theories by content and design experts to help reduce response burden and clarify questions. Thirty-two patients with chronic diseases (cancer, heart failure or renal failure) were recruited for the think aloud cognitive interviewing with the new, shortened survey evaluating patient engagement with ACP. Of these, n = 27 had data eligible for analysis (n = 8 in round 1 and n = 19 in rounds 2 and 3). Interviews were audio-recorded and analyzed using the constant comparison method. Three reviewers independently listened to the interviews, summarized findings and discussed discrepancies until consensus was achieved. Item reduction from key content expert review and conversation analysis helped decrease number of items from 116 in the original ACP Engagement Survey to 24-38 in the new BACPACS depending on branching of responses. For the think aloud study, three rounds of interviews were needed until saturation for patient clarity was achieved. The understanding of ACP as a construct, survey response options, instructions and terminology pertaining to patient engagement in ACP warranted further clarification. Conversation analysis, content expert review and think aloud cognitive interviewing were useful in refining the new survey instrument entitled BACPACS. We found evidence for both content and response process validity for this new tool.

  12. SU-E-T-471: Improvement of Gamma Knife Treatment Planning Through Tumor Control Probability for Metastatic Brain Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Z [East Carolina University, Greenville, NC (United States); Feng, Y [East Carolina Univ, Rockville, MD (United States); Lo, S [Case Western Reserve University, Cleveland, OH (United States); Grecula, J [Ohio State University, Columbus, OH (United States); Mayr, N; Yuh, W [University of Washington, Seattle, WA (United States)

    2015-06-15

    Purpose: The dose–volume histogram (DVH) has been normally accepted as a tool for treatment plan evaluation. However, spatial information is lacking in DVH. As a supplement to the DVH in three-dimensional treatment planning, the differential DVH (DDVH) provides the spatial variation, the size and magnitude of the different dose regions within a region of interest, which can be incorporated into tumor control probability model. This study was to provide a method in evaluating and improving Gamma Knife treatment planning. Methods: 10 patients with brain metastases from different primary tumors including melanoma (#1,#4,#5, #10), breast cancer (#2), prostate cancer (#3) and lung cancer (#6–9) were analyzed. By using Leksell GammaPlan software, two plans were prepared for each patient. Special attention was given to the DDVHs that were different for different plans and were used for a comparison between two plans. Dose distribution inside target and tumor control probability (TCP) based on DDVH were calculated, where cell density and radiobiological parameters were adopted from literature. The plans were compared based on DVH, DDVH and TCP. Results: Using DVH, the coverage and selectivity were the same between plans for 10 patients. DDVH were different between two plans for each patient. The paired t-test showed no significant difference in TCP between the two plans. For brain metastases from melanoma (#1, #4–5), breast cancer (#2) and lung cancer (#6–8), the difference in TCP was less than 5%. But the difference in TCP was about 6.5% for patient #3 with the metastasis from prostate cancer, 10.1% and 178.7% for two patients (#9–10) with metastasis from lung cancer. Conclusion: Although DVH provides average dose–volume information, DDVH provides differential dose– volume information with respect to different regions inside the tumor. TCP provides radiobiological information and adds additional information on improving treatment planning as well as adaptive

  13. SU-E-T-471: Improvement of Gamma Knife Treatment Planning Through Tumor Control Probability for Metastatic Brain Tumors

    International Nuclear Information System (INIS)

    Huang, Z; Feng, Y; Lo, S; Grecula, J; Mayr, N; Yuh, W

    2015-01-01

    Purpose: The dose–volume histogram (DVH) has been normally accepted as a tool for treatment plan evaluation. However, spatial information is lacking in DVH. As a supplement to the DVH in three-dimensional treatment planning, the differential DVH (DDVH) provides the spatial variation, the size and magnitude of the different dose regions within a region of interest, which can be incorporated into tumor control probability model. This study was to provide a method in evaluating and improving Gamma Knife treatment planning. Methods: 10 patients with brain metastases from different primary tumors including melanoma (#1,#4,#5, #10), breast cancer (#2), prostate cancer (#3) and lung cancer (#6–9) were analyzed. By using Leksell GammaPlan software, two plans were prepared for each patient. Special attention was given to the DDVHs that were different for different plans and were used for a comparison between two plans. Dose distribution inside target and tumor control probability (TCP) based on DDVH were calculated, where cell density and radiobiological parameters were adopted from literature. The plans were compared based on DVH, DDVH and TCP. Results: Using DVH, the coverage and selectivity were the same between plans for 10 patients. DDVH were different between two plans for each patient. The paired t-test showed no significant difference in TCP between the two plans. For brain metastases from melanoma (#1, #4–5), breast cancer (#2) and lung cancer (#6–8), the difference in TCP was less than 5%. But the difference in TCP was about 6.5% for patient #3 with the metastasis from prostate cancer, 10.1% and 178.7% for two patients (#9–10) with metastasis from lung cancer. Conclusion: Although DVH provides average dose–volume information, DDVH provides differential dose– volume information with respect to different regions inside the tumor. TCP provides radiobiological information and adds additional information on improving treatment planning as well as adaptive

  14. Volume arc therapy of gynaecological tumours: target volume coverage improvement without dose increase for critical organs; Arctherapie volumique des tumeurs gynecologiques: amelioration de la couverture du volume cible sans augmentation de la dose aux organes critiques

    Energy Technology Data Exchange (ETDEWEB)

    Ducteil, A.; Kerr, C.; Idri, K.; Fenoglietto, P.; Vieillot, S.; Ailleres, N.; Dubois, J.B.; Azria, D. [CRLC Val-d' Aurelle, Montpellier (France)

    2011-10-15

    The authors report the assessment of the application of conventional intensity-modulated conformational radiotherapy (IMRT) and volume arc-therapy (RapidArc) for the treatment of cervical cancers, with respect to conventional radiotherapy. Dosimetric plans associated with each of these techniques have been compared. Dose-volume histograms of these three plans have also been compared for the previsional target volume (PTV), organs at risk, and sane tissue. IMCT techniques are equivalent in terms of sparing of organs at risk, and improve target volume coverage with respect to conventional radiotherapy. Arc-therapy reduces significantly treatment duration. Short communication

  15. Validity of PRV margins around lung and heart during left breast irradiation

    International Nuclear Information System (INIS)

    Stefanovski, Zoran

    2010-01-01

    Planning organ at risk volumes (PRV) has a minor use in radiotherapy treatment planning. During left breast irradiation two critical volumes are of special importance the lung and the heart. The aim of this study was to evaluate the changes in volume doses after adding appropriate margins around these organs at risk and compare them with the effect that the systematic positioning error has on the volume doses. Methods: Treatment plans for 44 patients with left breast cancer were analyzed. Two changes for each plan were made, and dose-volume histogram values for hearts and lungs volumes were recorded. In the first case margins of 5 mm to hearts and lungs were added. Volumes that were enclosed by 30% isodose for hearts and volumes that were enclosed by 20% isodose of lungs were recorded. In the second case plans were made with a systematic error of 5 mm employed, depicting a translation of isocenter posterior and to the right. In this second case, monitor units were taken from the original plan. The critical volumes for hearts and lungs were recorded as in the first case. Results: Our policy for breast cancer irradiation demands that the lung volume receiving 20 Gy should be kept under 25% of the whole left-lung volume, and no more than 10% of the heart volume should receive more than 30 Gy. The first case simulation showed that 23% of the patients have a heart overdose while 11% of them have a lung overdose according to the criteria above. Simulation of the second kind showed that the systematic error in isocenter positioning of 5 mm gives bigger a volume of the heart (in average 0.69% of heart volume) to be enclosed in critical isodose than in PRV case. For the lung the situation was opposite; namely in PRV case the lung volume that is encompassed with critical isodose is greater (in average 1.47% of lung volume) than in a case of displaced isocenter. Conclusions: Adding PRV margins around the heart and the lung does not give straightforward and unambiguous result

  16. Strategy for Alternative Occupant Volume Testing

    Science.gov (United States)

    2009-10-20

    This paper describes plans for a series of quasi-static : compression tests of rail passenger equipment. These tests are : designed to evaluate the strength of the occupant volume under : static loading conditions. The research plan includes a detail...

  17. SU-F-J-94: Development of a Plug-in Based Image Analysis Tool for Integration Into Treatment Planning

    Energy Technology Data Exchange (ETDEWEB)

    Owen, D; Anderson, C; Mayo, C; El Naqa, I; Ten Haken, R; Cao, Y; Balter, J; Matuszak, M [University of Michigan, Ann Arbor, MI (United States)

    2016-06-15

    Purpose: To extend the functionality of a commercial treatment planning system (TPS) to support (i) direct use of quantitative image-based metrics within treatment plan optimization and (ii) evaluation of dose-functional volume relationships to assist in functional image adaptive radiotherapy. Methods: A script was written that interfaces with a commercial TPS via an Application Programming Interface (API). The script executes a program that performs dose-functional volume analyses. Written in C#, the script reads the dose grid and correlates it with image data on a voxel-by-voxel basis through API extensions that can access registration transforms. A user interface was designed through WinForms to input parameters and display results. To test the performance of this program, image- and dose-based metrics computed from perfusion SPECT images aligned to the treatment planning CT were generated, validated, and compared. Results: The integration of image analysis information was successfully implemented as a plug-in to a commercial TPS. Perfusion SPECT images were used to validate the calculation and display of image-based metrics as well as dose-intensity metrics and histograms for defined structures on the treatment planning CT. Various biological dose correction models, custom image-based metrics, dose-intensity computations, and dose-intensity histograms were applied to analyze the image-dose profile. Conclusion: It is possible to add image analysis features to commercial TPSs through custom scripting applications. A tool was developed to enable the evaluation of image-intensity-based metrics in the context of functional targeting and avoidance. In addition to providing dose-intensity metrics and histograms that can be easily extracted from a plan database and correlated with outcomes, the system can also be extended to a plug-in optimization system, which can directly use the computed metrics for optimization of post-treatment tumor or normal tissue response

  18. Re-assessing Rainwater Harvesting Volume by CHIRPS Satellite in Semarang Settlement Area

    Science.gov (United States)

    Prihanto, Yosef; Koestoer, Raldi H.; Sutjiningsih, Dwita

    2017-12-01

    Semarang City is one of the most influential coastal cities in Java Island. The city is facing increasingly-high water demand due to its development and water problems due to climate change. The spatial physiography and landscape of Semarang City are also exposed the city to water security problem. Hence, rainwater harvesting treatment is an urgent effort to meet the city’s water needs. However, planning, implementation and management of rainwater harvesting are highly depended on multitemporal rainfall data. It has not yet been fully compiled due to limited rain stations. This study aims to examine the extent to which CHIRPS satellite data can be utilized in estimating volume of rainwater harvesting 16 sub-districts in Semarang and determine the water security status. This study uses descriptive statistical method based on spatial analyses. Such method was developed through spatial modeling for rainfall using isohyetal model. The parameters used are rainfall, residential rooftop area, administrative area, population, physiographic and altitude units. Validation is carried out by using monthly 10 rain stations data. The results show level of validity by utilizing CHIRPS Satellite data and mapping rainfall distribution. This study also produces a potential map of distribution rainfall volume that can be harvested in 16 sub-districts of Semarang.

  19. On-line MR imaging for dose validation of abdominal radiotherapy

    International Nuclear Information System (INIS)

    Glitzner, M; Crijns, S P M; De Senneville, B Denis; Kontaxis, C; Prins, F M; Lagendijk, J J W; Raaymakers, B W

    2015-01-01

    For quality assurance and adaptive radiotherapy, validation of the actual delivered dose is crucial.Intrafractional anatomy changes cannot be captured satisfactorily during treatment with hitherto available imaging modalitites. Consequently, dose calculations are based on the assumption of static anatomy throughout the treatment. However, intra- and interfraction anatomy is dynamic and changes can be significant.In this paper, we investigate the use of an MR-linac as a dose tracking modality for the validation of treatments in abdominal targets where both respiratory and long-term peristaltic and drift motion occur.The on-line MR imaging capability of the modality provides the means to perform respiratory gating of both delivery and acquisition yielding a model-free respiratory motion management under free breathing conditions.In parallel to the treatment, the volumetric patient anatomy was captured and used to calculate the applied dose. Subsequently, the individual doses were warped back to the planning grid to obtain the actual dose accumulated over the entire treatment duration. Ultimately, the planned dose was validated by comparison with the accumulated dose.Representative for a site subject to breathing modulation, two kidney cases (25 Gy target dose) demonstrated the working principle on volunteer data and simulated delivery. The proposed workflow successfully showed its ability to track local dosimetric changes. Integration of the on-line anatomy information could reveal local dose variations  −2.3–1.5 Gy in the target volume of a volunteer dataset. In the adjacent organs at risk, high local dose errors ranging from  −2.5 to 1.9 Gy could be traced back. (paper)

  20. On-line MR imaging for dose validation of abdominal radiotherapy

    Science.gov (United States)

    Glitzner, M.; Crijns, S. P. M.; de Senneville, B. Denis; Kontaxis, C.; Prins, F. M.; Lagendijk, J. J. W.; Raaymakers, B. W.

    2015-11-01

    For quality assurance and adaptive radiotherapy, validation of the actual delivered dose is crucial. Intrafractional anatomy changes cannot be captured satisfactorily during treatment with hitherto available imaging modalitites. Consequently, dose calculations are based on the assumption of static anatomy throughout the treatment. However, intra- and interfraction anatomy is dynamic and changes can be significant. In this paper, we investigate the use of an MR-linac as a dose tracking modality for the validation of treatments in abdominal targets where both respiratory and long-term peristaltic and drift motion occur. The on-line MR imaging capability of the modality provides the means to perform respiratory gating of both delivery and acquisition yielding a model-free respiratory motion management under free breathing conditions. In parallel to the treatment, the volumetric patient anatomy was captured and used to calculate the applied dose. Subsequently, the individual doses were warped back to the planning grid to obtain the actual dose accumulated over the entire treatment duration. Ultimately, the planned dose was validated by comparison with the accumulated dose. Representative for a site subject to breathing modulation, two kidney cases (25 Gy target dose) demonstrated the working principle on volunteer data and simulated delivery. The proposed workflow successfully showed its ability to track local dosimetric changes. Integration of the on-line anatomy information could reveal local dose variations  -2.3-1.5 Gy in the target volume of a volunteer dataset. In the adjacent organs at risk, high local dose errors ranging from  -2.5 to 1.9 Gy could be traced back.

  1. Definition of internal target volume and domestric study for hepatocellular carcinoma using four-dimensional CT

    International Nuclear Information System (INIS)

    Xi Mian; Liu Mengzhong; Deng Xiaowu; Zhang Li; Huang Xiaoyan; Cai Ling

    2009-01-01

    Objective: To define individualized internal target volume (ITV) for hepatocellular carcinoma using four-dimensional (4D) CT, and to compare the differences in target volume definition and dose distribution among 3D, 4D and respiratory-gated plans. Methods: 4DCT scanning was obtained for 12 patients with hepatocellular. Gross tumor volume (GTV), clinical target volume (CTV) and normal tissues were contoured on all 10 respiratory phases of 4DCT images. The 3D, 4D and gated treatment plans were prepared for each patient using three different planning target volumes (PTVs): 1) PTV 3D was derived from a single CTV plus conventional margins; 2) PTV 4D was derived from ITV 4D , which encompassed all 10 CTVs plus setup margins (SMs); 3) PT Gating was derived from ITV Gating , which encompassed 3 CTVs within gating-window at end-expiration plus SMs. The PTV volume and dose distribution were compared among different plans. Results: The PTV3D was the largest in all 12 patients, but still missed partial target volume in 5 patients when comparing with PTV4D. Both the 4D plans and the gated plans spared more normal tissues than the 3D plans, especially the liver. Without increasing normal tissue dose, the 4D plans allowed for increasing the calculated dose from (50.8 ± 2.0) Gy (3D plans) to (54.7 ± 3.3) Gy, and the gated plans could further increase the dose to (58.0 ± 3.9) Gy. Conclusions: The 4DCT-based plans can ensure optimal target coverage with less irradiation of normal tissues and allow dose escalation when compared with 3D plans. Respiratory gated radiotherapy can further reduce the target volumes to spare more surrounding tissues, especially for patients with large extent of respiratory mobility. (authors)

  2. An Architecture for Robot Assemblt Task Planning

    DEFF Research Database (Denmark)

    Sun, Hongyan

    1999-01-01

    This paper discusses an integrated robot assembly task planning system architecture. In such an integrated system, the robot motion commands produced from the planning system can be validated before done-loading for actual execution.......This paper discusses an integrated robot assembly task planning system architecture. In such an integrated system, the robot motion commands produced from the planning system can be validated before done-loading for actual execution....

  3. Logistics and Planning of Output Volume

    Directory of Open Access Journals (Sweden)

    V. I. Pokhabov

    2005-01-01

    Full Text Available On the basis of logistics conception the paper considers an adaptation of an enterprise to environmental changes with due account of its emergement properties. Taking into account emergement properties of an enterprise a logistics method for planning an optimum movement of the material flow is proposed in the paper.

  4. A global quality assurance system for personalized radiation therapy treatment planning for the prostate (or other sites)

    International Nuclear Information System (INIS)

    Nwankwo, Obioma; Sihono, Dwi Seno K; Schneider, Frank; Wenz, Frederik

    2014-01-01

    Introduction: the quality of radiotherapy treatment plans varies across institutions and depends on the experience of the planner. For the purpose of intra- and inter-institutional homogenization of treatment plan quality, we present an algorithm that learns the organs-at-risk (OARs) sparing patterns from a database of high quality plans. Thereafter, the algorithm predicts the dose that similar organs will receive in future radiotherapy plans prior to treatment planning on the basis of the anatomies of the organs. The predicted dose provides the basis for the individualized specification of planning objectives, and for the objective assessment of the quality of radiotherapy plans. Materials and method: one hundred and twenty eight (128) Volumetric Modulated Arc Therapy (VMAT) plans were selected from a database of prostate cancer plans. The plans were divided into two groups, namely a training set that is made up of 95 plans and a validation set that consists of 33 plans. A multivariate analysis technique was used to determine the relationships between the positions of voxels and their dose. This information was used to predict the likely sparing of the OARs of the plans of the validation set. The predicted doses were visually and quantitatively compared to the reference data using dose volume histograms, the 3D dose distribution, and a novel evaluation metric that is based on the dose different test. Results: a voxel of the bladder on the average receives a higher dose than a voxel of the rectum in optimized radiotherapy plans for the treatment of prostate cancer in our institution if both voxels are at the same distance to the PTV. Based on our evaluation metric, the predicted and reference dose to the bladder agree to within 5% of the prescribed dose to the PTV in 18 out of 33 cases, while the predicted and reference doses to the rectum agree to within 5% in 28 out of the 33 plans of the validation set. Conclusion: We have described a method to predict the

  5. A global quality assurance system for personalized radiation therapy treatment planning for the prostate (or other sites)

    Science.gov (United States)

    Nwankwo, Obioma; Sihono, Dwi Seno K.; Schneider, Frank; Wenz, Frederik

    2014-09-01

    Introduction: the quality of radiotherapy treatment plans varies across institutions and depends on the experience of the planner. For the purpose of intra- and inter-institutional homogenization of treatment plan quality, we present an algorithm that learns the organs-at-risk (OARs) sparing patterns from a database of high quality plans. Thereafter, the algorithm predicts the dose that similar organs will receive in future radiotherapy plans prior to treatment planning on the basis of the anatomies of the organs. The predicted dose provides the basis for the individualized specification of planning objectives, and for the objective assessment of the quality of radiotherapy plans. Materials and method: one hundred and twenty eight (128) Volumetric Modulated Arc Therapy (VMAT) plans were selected from a database of prostate cancer plans. The plans were divided into two groups, namely a training set that is made up of 95 plans and a validation set that consists of 33 plans. A multivariate analysis technique was used to determine the relationships between the positions of voxels and their dose. This information was used to predict the likely sparing of the OARs of the plans of the validation set. The predicted doses were visually and quantitatively compared to the reference data using dose volume histograms, the 3D dose distribution, and a novel evaluation metric that is based on the dose different test. Results: a voxel of the bladder on the average receives a higher dose than a voxel of the rectum in optimized radiotherapy plans for the treatment of prostate cancer in our institution if both voxels are at the same distance to the PTV. Based on our evaluation metric, the predicted and reference dose to the bladder agree to within 5% of the prescribed dose to the PTV in 18 out of 33 cases, while the predicted and reference doses to the rectum agree to within 5% in 28 out of the 33 plans of the validation set. Conclusion: We have described a method to predict the

  6. Translation, adaptation and validation the contents of the Diabetes Medical Management Plan for the Brazilian context.

    Science.gov (United States)

    Torres, Heloísa de Carvalho; Chaves, Fernanda Figueredo; Silva, Daniel Dutra Romualdo da; Bosco, Adriana Aparecida; Gabriel, Beatriz Diniz; Reis, Ilka Afonso; Rodrigues, Júlia Santos Nunes; Pagano, Adriana Silvina

    2016-08-08

    to translate, adapt and validate the contents of the Diabetes Medical Management Plan for the Brazilian context. This protocol was developed by the American Diabetes Association and guides the procedure of educators for the care of children and adolescents with diabetes in schools. this methodological study was conducted in four stages: initial translation, synthesis of initial translation, back translation and content validation by an expert committee, composed of 94 specialists (29 applied linguists and 65 health professionals), for evaluation of the translated version through an online questionnaire. The concordance level of the judges was calculated based on the Content Validity Index. Data were exported into the R program for statistical analysis. the evaluation of the instrument showed good concordance between the judges of the Health and Applied Linguistics areas, with a mean content validity index of 0.9 and 0.89, respectively, and slight variability of the index between groups (difference of less than 0.01). The items in the translated version, evaluated as unsatisfactory by the judges, were reformulated based on the considerations of the professionals of each group. a Brazilian version of Diabetes Medical Management Plan was constructed, called the Plano de Manejo do Diabetes na Escola. traduzir, adaptar e validar o conteúdo do Diabetes Medical Management Plan para o contexto brasileiro, protocolo elaborado pela Associação Americana de Diabetes, que orienta a conduta dos educadores para o cuidado das crianças e adolescentes com diabetes mellitus nas escolas. trata-se de estudo metodológico, realizado em quatro etapas: tradução inicial, síntese da tradução inicial, retrotradução e validação de conteúdo por um Comitê de Juízes, composto por 94 especialistas (29 linguistas aplicados e 65 profissionais da área da Saúde), para avaliação da versão traduzida por meio de um questionário online. O nível de concordância dos juízes foi

  7. IMRT for adjuvant radiation in gastric cancer: A preferred plan?

    International Nuclear Information System (INIS)

    Ringash, Jolie; Perkins, Greg; Brierley, James; Lockwood, Gina; Islam, Mohammad; Catton, Pamela; Cummings, Bernard; Kim, John; Wong, Rebecca; Dawson, Laura

    2005-01-01

    Purpose: To assess the potential advantage of intensity-modulated radiotherapy (IMRT) over conformal planning for postoperative adjuvant radiotherapy in patients with gastric carcinoma. Methods and Materials: Twenty patients who had undergone treatment planning with conformal beam arrangements for 4500 cGy adjuvant radiotherapy between 2000 and 2001 underwent repeat planning using IMRT techniques. Conformal five-field plans were compared with seven- to nine-field coplanar sliding-window IMRT plans. For each patient, the cumulative dose-volume histograms and organ-dose summaries (without distributions or digitally reconstructed radiographs) were provided to two independent, 'blinded' GI radiation oncologists. The oncologists indicated which plan provided better planning target volume coverage and critical organ sparing, any safety concerns with either plan, and which plan they would choose to treat the patient. Results: In 18 (90%) of 20 cases, both oncologists chose the same plan. Cases with disagreement were given to a third 'blinded' reviewer. A 'preferred plan' could be determined in 19 (95%) of 20 cases. IMRT was preferred in 17 (89%) of 19 cases. In 4 (20%) of 20 IMRT plans at least one radiation oncologist had safety concerns because of the spinal cord dose (3 cases) or small bowel dose (2 cases). Of 42 ratings, IMRT was thought to provide better planning target volume coverage in 36 (86%) and better sparing of the spinal cord in 31 (74%) of 42, kidneys in 29 (69%), liver in 30 (71%), and heart in 29 (69%) of 42 ratings. The median underdose volume (1.7 vs. 4.1 cm 3 ), maximal dose to the spinal cord (36.85 vs. 45.65 Gy), and dose to 50% of the liver (17.29 vs. 27.97), heart (12.89 vs. 15.50 Gy), and left kidney (15.50 vs. 16.06 Gy) were lower with IMRT than with the conformal plans. Conclusion: Compared with the conformal plans, oncologists frequently preferred IMRT plans when using dose-volume histogram data. The advantages of IMRT plans include both

  8. Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

    Energy Technology Data Exchange (ETDEWEB)

    Felmly, Lloyd M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiothoracic Surgery, Department of Surgery, Charleston, SC (United States); De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Vogl, Thomas J. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany)

    2017-05-15

    To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m{sup 2} vs. 28.1±5.4 kg/m{sup 2}, P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

  9. Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

    International Nuclear Information System (INIS)

    Felmly, Lloyd M.; De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D.; Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R.; Mangold, Stefanie; Vogl, Thomas J.; Wichmann, Julian L.

    2017-01-01

    To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m 2 vs. 28.1±5.4 kg/m 2 , P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

  10. Iterative volume morphing and learning for mobile tumor based on 4DCT.

    Science.gov (United States)

    Mao, Songan; Wu, Huanmei; Sandison, George; Fang, Shiaofen

    2017-02-21

    During image-guided cancer radiation treatment, three-dimensional (3D) tumor volumetric information is important for treatment success. However, it is typically not feasible to image a patient's 3D tumor continuously in real time during treatment due to concern over excessive patient radiation dose. We present a new iterative morphing algorithm to predict the real-time 3D tumor volume based on time-resolved computed tomography (4DCT) acquired before treatment. An offline iterative learning process has been designed to derive a target volumetric deformation function from one breathing phase to another. Real-time volumetric prediction is performed to derive the target 3D volume during treatment delivery. The proposed iterative deformable approach for tumor volume morphing and prediction based on 4DCT is innovative because it makes three major contributions: (1) a novel approach to landmark selection on 3D tumor surfaces using a minimum bounding box; (2) an iterative morphing algorithm to generate the 3D tumor volume using mapped landmarks; and (3) an online tumor volume prediction strategy based on previously trained deformation functions utilizing 4DCT. The experimental performance showed that the maximum morphing deviations are 0.27% and 1.25% for original patient data and artificially generated data, which is promising. This newly developed algorithm and implementation will have important applications for treatment planning, dose calculation and treatment validation in cancer radiation treatment.

  11. Simultaneous optimization of sequential IMRT plans

    International Nuclear Information System (INIS)

    Popple, Richard A.; Prellop, Perri B.; Spencer, Sharon A.; Santos, Jennifer F. de los; Duan, Jun; Fiveash, John B.; Brezovich, Ivan A.

    2005-01-01

    Radiotherapy often comprises two phases, in which irradiation of a volume at risk for microscopic disease is followed by a sequential dose escalation to a smaller volume either at a higher risk for microscopic disease or containing only gross disease. This technique is difficult to implement with intensity modulated radiotherapy, as the tolerance doses of critical structures must be respected over the sum of the two plans. Techniques that include an integrated boost have been proposed to address this problem. However, clinical experience with such techniques is limited, and many clinicians are uncomfortable prescribing nonconventional fractionation schemes. To solve this problem, we developed an optimization technique that simultaneously generates sequential initial and boost IMRT plans. We have developed an optimization tool that uses a commercial treatment planning system (TPS) and a high level programming language for technical computing. The tool uses the TPS to calculate the dose deposition coefficients (DDCs) for optimization. The DDCs were imported into external software and the treatment ports duplicated to create the boost plan. The initial, boost, and tolerance doses were specified and used to construct cost functions. The initial and boost plans were optimized simultaneously using a gradient search technique. Following optimization, the fluence maps were exported to the TPS for dose calculation. Seven patients treated using sequential techniques were selected from our clinical database. The initial and boost plans used to treat these patients were developed independently of each other by dividing the tolerance doses proportionally between the initial and boost plans and then iteratively optimizing the plans until a summation that met the treatment goals was obtained. We used the simultaneous optimization technique to generate plans that met the original planning goals. The coverage of the initial and boost target volumes in the simultaneously optimized

  12. Changes in atheroma volume estimated from digitized femoral arteriograms

    International Nuclear Information System (INIS)

    Nilsson, S.; Erikson, U.

    1990-01-01

    To evaluate the effects of treatment in patients with cardiovascular risk factors, valid and reproducible methods for assessing changes in atheroma volume are required. We postulated that these changes could be accurately estimated by repeat measurement of the lumen volume of the artery to be studied. With a computer-based technique, the lumen volume of a 20 cm segment of the femoral artery was measured in arteriograms from 107 patients with hypercholesterolemia. Films were digitized with use of a high-resolution scanner, cross-sectional areas were calculated with a slice thickness of 150 μm and the lumen volume was obtained by their integration. The validity of the method was demonstrated in model experiments. An automatic algorithm to correct for changes due to patient positioning was developed and validated in a model experiment. With repeat measurment 10 min and 11 to 13 months apart the coefficients of variation were 2.9% (N=107) and 6.1% (N=29), respectively. (orig.)

  13. Definition of technology development missions for early Space Station satellite servicing. Volume 2: Technical

    Science.gov (United States)

    Cable, D. A.; Diewald, C. A.; Hills, T. C.; Parmentier, T. J.; Spencer, R. A.; Stone, G. E.

    1984-01-01

    Volume 2 contains the Technical Report of the approach and results of the Phase 2 study. The phase 2 servicing study was initiated in June 1983, and is being reported in this document. The scope of the contract was to: (1) define in detail five selected technology development missions (TDM); (2) conduct a design requirement analysis to refine definitions of satellite servicing requirements at the space station; and (3) develop a technology plan that would identify and schedule prerequisite precursor technology development, associated. STS flight experiments and space station experiments needed to provide onorbit validation of the evolving technology.

  14. Computerised tomography in radiotherapy planning

    International Nuclear Information System (INIS)

    Badcock, P.C.

    1983-01-01

    This study evaluates the effectiveness of computed tomography as an adjunct to radiotherapy planning. Until recently, acquisition of accurate data concerning tumour anatomy lagged behind other developments in radiotherapy. With the advent of computer-tomography (CT), these data can be displayed and transmitted to a treatment planning computer. It is concluded that the greatest inaccuracies in the radiation treatment of patients are to be found in both the inadequate delineation of the target volume within the patient and changes in body outline relative to the target volume over the length of the irradiated volume. The technique was useful in various subgroups (pelvic, intra-thoracic and chest-wall tumours) and for those patients being treated palliatively. With an estimated improvement in cure rate of 4.5% and cost-effective factors of between 3.3 and 5, CT-assisted radiotherapy planning appears to be a worthwhile procedure. (orig.)

  15. Validation Plan of Turbulence Models for Internal Gas Flow Analysis in a Heated Rectangular Riser Duct

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sin-Yeob; Shin, Dong-Ho; Park, Goon-Cherl; Cho, Hyoung Kyu [Seoul National Univ., Seoul (Korea, Republic of); Kim, Chan-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    VHTR being developed at Korea Atomic Energy Research Institute adopts an air-cooled Reactor Cavity Cooling System (RCCS) incorporating rectangular riser channels to remove the afterheat emitted from the reactor vessel. Because the performance of RCCS is determined by heat removal rate through the RCCS riser, it is important to understand the heat transfer phenomena in the RCCS riser to ensure the safety of the reactor. In the mixed convection, due to the buoyance force induced by temperature and density differences, local flow structure and heat transfer mode near the heated wall have significantly dissimilar characteristics from both forced convection and free convection. In this study, benchmark calculation was conducted to reproduce the previous statements that V2F turbulence model can capture the mixed convection phenomena with the Shehata's experimental data. Then, the necessity of the model validation for the mixed convection phenomena was confirmed with the CFD analyses for the geometry of the prototype RCCS riser. For the purpose of validating the turbulence models for mixed convection phenomena in the heated rectangular riser duct, validation plan with three experimental tests was introduced. Among them, the flow visualization test facility with preserved cross-section geometry was introduced and a preliminary test result was shown.

  16. Hybrid IMRT plans-concurrently treating conventional and IMRT beams for improved breast irradiation and reduced planning time

    International Nuclear Information System (INIS)

    Mayo, Charles S.; Urie, Marcia M.; Fitzgerald, Thomas J.

    2005-01-01

    Purpose: To evaluate a hybrid intensity modulated radiation therapy (IMRT) technique as a class solution for treatment of the intact breast. Methods and materials: The following five plan techniques were compared for 10 breast patients using dose-volume histogram analysis: conventional wedged-field tangents (Tangents), forward-planned field-within-a-field tangents (FIF), IMRT-only tangents (IMRT tangents), conventional open plus IMRT tangents (4-field hybrid), and conventional open plus IMRT tangents with 2 anterior oblique IMRT beams (6-field hybrid). Results: The 4-field hybrid and FIF achieved dose distributions better than Tangents and IMRT tangents. The volume of tissue outside the planning target volume receiving ≥110% of prescribed dose was largest for IMRT tangents (average 158 cc) and least for 6-field hybrid (average 1 cc); the FIF and 4-field hybrid were comparable (average 15 cc). Heart volume ≥30 Gy averaged 13 cc for all techniques, except Tangents, for which it was 32 cc. Average total lung volume ≥20 Gy was 7% for all. Contralateral breast doses were < 3% for all. Planning time for hybrid techniques was significantly less than for conventional FIF technique. Conclusions: The 4-field hybrid technique is a viable class solution. The 6-field hybrid technique creates the most conformal dose distribution at the expense of more normal tissue receiving low dose

  17. Evaluation of a software module for adaptive treatment planning and re-irradiation.

    Science.gov (United States)

    Richter, Anne; Weick, Stefan; Krieger, Thomas; Exner, Florian; Kellner, Sonja; Polat, Bülent; Flentje, Michael

    2017-12-28

    The aim of this work is to validate the Dynamic Planning Module in terms of usability and acceptance in the treatment planning workflow. The Dynamic Planning Module was used for decision making whether a plan adaptation was necessary within one course of radiation therapy. The Module was also used for patients scheduled for re-irradiation to estimate the dose in the pretreated region and calculate the accumulated dose to critical organs at risk. During one year, 370 patients were scheduled for plan adaptation or re-irradiation. All patient cases were classified according to their treated body region. For a sub-group of 20 patients treated with RT for lung cancer, the dosimetric effect of plan adaptation during the main treatment course was evaluated in detail. Changes in tumor volume, frequency of re-planning and the time interval between treatment start and plan adaptation were assessed. The Dynamic Planning Tool was used in 20% of treated patients per year for both approaches nearly equally (42% plan adaptation and 58% re-irradiation). Most cases were assessed for the thoracic body region (51%) followed by pelvis (21%) and head and neck cases (10%). The sub-group evaluation showed that unintended plan adaptation was performed in 38% of the scheduled cases. A median time span between first day of treatment and necessity of adaptation of 17 days (range 4-35 days) was observed. PTV changed by 12 ± 12% on average (maximum change 42%). PTV decreased in 18 of 20 cases due to tumor shrinkage and increased in 2 of 20 cases. Re-planning resulted in a reduction of the mean lung dose of the ipsilateral side in 15 of 20 cases. The experience of one year showed high acceptance of the Dynamic Planning Module in our department for both physicians and medical physicists. The re-planning can potentially reduce the accumulated dose to the organs at risk and ensure a better target volume coverage. In the re-irradiation situation, the Dynamic Planning Tool was used to

  18. Cerebrospinal fluid volume measurements in hydrocephalic rats.

    Science.gov (United States)

    Basati, Sukhraaj; Desai, Bhargav; Alaraj, Ali; Charbel, Fady; Linninger, Andreas

    2012-10-01

    Object Experimental data about the evolution of intracranial volume and pressure in cases of hydrocephalus are limited due to the lack of available monitoring techniques. In this study, the authors validate intracranial CSF volume measurements within the lateral ventricle, while simultaneously using impedance sensors and pressure transducers in hydrocephalic animals. Methods A volume sensor was fabricated and connected to a catheter that was used as a shunt to withdraw CSF. In vitro bench-top calibration experiments were created to provide data for the animal experiments and to validate the sensors. To validate the measurement technique in a physiological system, hydrocephalus was induced in weanling rats by kaolin injection into the cisterna magna. At 28 days after induction, the sensor was implanted into the lateral ventricles. After sealing the skull using dental cement, an acute CSF drainage/infusion protocol consisting of 4 sequential phases was performed with a pump. Implant location was confirmed via radiography using intraventricular iohexol contrast administration. Results Controlled CSF shunting in vivo with hydrocephalic rats resulted in precise and accurate sensor measurements (r = 0.98). Shunting resulted in a 17.3% maximum measurement error between measured volume and actual volume as assessed by a Bland-Altman plot. A secondary outcome confirmed that both ventricular volume and intracranial pressure decreased during CSF shunting and increased during infusion. Ventricular enlargement consistent with successful hydrocephalus induction was confirmed using imaging, as well as postmortem. These results indicate that volume monitoring is feasible for clinical cases of hydrocephalus. Conclusions This work marks a departure from traditional shunting systems currently used to treat hydrocephalus. The overall clinical application is to provide alternative monitoring and treatment options for patients. Future work includes development and testing of a chronic

  19. Volume reduction philosophy and techniques in use or planned

    Energy Technology Data Exchange (ETDEWEB)

    Row, T.H.

    1984-01-01

    Siting and development of nuclear waste disposal facilities is an expensive task. In the private sector, such developments face siting and licensing issues, public intervention, and technology challenges. The United States Department of Energy (DOE) faces similar challenges in the management of waste generated by the research and production facilities. Volume reduction can be used to lengthen the service life of existing facilities. A wide variety of volume reduction techniques are applied to different waste forms. Compressible waste is compacted into drums, cardboard and metal boxes, and the loaded drums are supercompacted into smaller units. Large metallic items are size-reduced and melted for recycle or sent to shallow land burial. Anaerobic digestion is a process that can reduce cellulosic and animal wastes by 80%. Incinerators of all types have been investigated for application to nuclear wastes and a number of installations operate or are constructing units for low-level and transuranic solid and liquid combustibles. Technology may help solve many of the problems in volume reduction, but the human element also has an important part in solving the puzzle. Aggressive educational campaigns at two sites have proved very successful in reducing waste generation. This overview of volume reduction is intended to transfer the current information from many DOE facilities. 44 references, 85 figures, 5 tables.

  20. Volume reduction philosophy and techniques in use or planned

    International Nuclear Information System (INIS)

    Row, T.H.

    1984-01-01

    Siting and development of nuclear waste disposal facilities is an expensive task. In the private sector, such developments face siting and licensing issues, public intervention, and technology challenges. The United States Department of Energy (DOE) faces similar challenges in the management of waste generated by the research and production facilities. Volume reduction can be used to lengthen the service life of existing facilities. A wide variety of volume reduction techniques are applied to different waste forms. Compressible waste is compacted into drums, cardboard and metal boxes, and the loaded drums are supercompacted into smaller units. Large metallic items are size-reduced and melted for recycle or sent to shallow land burial. Anaerobic digestion is a process that can reduce cellulosic and animal wastes by 80%. Incinerators of all types have been investigated for application to nuclear wastes and a number of installations operate or are constructing units for low-level and transuranic solid and liquid combustibles. Technology may help solve many of the problems in volume reduction, but the human element also has an important part in solving the puzzle. Aggressive educational campaigns at two sites have proved very successful in reducing waste generation. This overview of volume reduction is intended to transfer the current information from many DOE facilities. 44 references, 85 figures, 5 tables

  1. Customized Computed Tomography-Based Boost Volumes in Breast-Conserving Therapy: Use of Three-Dimensional Histologic Information for Clinical Target Volume Margins

    International Nuclear Information System (INIS)

    Hanbeukers, Bianca; Borger, Jacques; Ende, Piet van den; Ent, Fred van der; Houben, Ruud; Jager, Jos; Keymeulen, Kristien; Murrer, Lars; Sastrowijoto, Suprapto; Vijver, Koen van de; Boersma, Liesbeth

    2009-01-01

    Purpose: To determine the difference in size between computed tomography (CT)-based irradiated boost volumes and simulator-based irradiated volumes in patients treated with breast-conserving therapy and to analyze whether the use of anisotropic three-dimensional clinical target volume (CTV) margins using the histologically determined free resection margins allows for a significant reduction of the CT-based boost volumes. Patients and Methods: The CT data from 49 patients were used to delineate a planning target volume (PTV) with isotropic CTV margins and to delineate a PTV sim that mimicked the PTV as delineated in the era of conventional simulation. For 17 patients, a PTV with anisotropic CTV margins was defined by applying customized three-dimensional CTV margins, according to the free excision margins in six directions. Boost treatment plans consisted of conformal portals for the CT-based PTVs and rectangular fields for the PTV sim . Results: The irradiated volume (volume receiving ≥95% of the prescribed dose [V 95 ]) for the PTV with isotropic CTV margins was 1.6 times greater than that for the PTV sim : 228 cm 3 vs. 147 cm 3 (p 95 was similar to the V 95 for the PTV sim (190 cm 3 vs. 162 cm 3 ; p = NS). The main determinant for the irradiated volume was the size of the excision cavity (p < .001), which was mainly related to the interval between surgery and the planning CT scan (p = .029). Conclusion: CT-based PTVs with isotropic margins for the CTV yield much greater irradiated volumes than fluoroscopically based PTVs. Applying individualized anisotropic CTV margins allowed for a significant reduction of the irradiated boost volume.

  2. Guidelines for the verification and validation of expert system software and conventional software: Project summary. Volume 1

    International Nuclear Information System (INIS)

    Mirsky, S.M.; Hayes, J.E.; Miller, L.A.

    1995-03-01

    This eight-volume report presents guidelines for performing verification and validation (V ampersand V) on Artificial Intelligence (Al) systems with nuclear applications. The guidelines have much broader application than just expert systems; they are also applicable to object-oriented programming systems, rule-based systems, frame-based systems, model-based systems, neural nets, genetic algorithms, and conventional software systems. This is because many of the components of AI systems are implemented in conventional procedural programming languages, so there is no real distinction. The report examines the state of the art in verifying and validating expert systems. V ampersand V methods traditionally applied to conventional software systems are evaluated for their applicability to expert systems. One hundred fifty-three conventional techniques are identified and evaluated. These methods are found to be useful for at least some of the components of expert systems, frame-based systems, and object-oriented systems. A taxonomy of 52 defect types and their delectability by the 153 methods is presented. With specific regard to expert systems, conventional V ampersand V methods were found to apply well to all the components of the expert system with the exception of the knowledge base. The knowledge base requires extension of the existing methods. Several innovative static verification and validation methods for expert systems have been identified and are described here, including a method for checking the knowledge base open-quotes semanticsclose quotes and a method for generating validation scenarios. Evaluation of some of these methods was performed both analytically and experimentally. A V ampersand V methodology for expert systems is presented based on three factors: (1) a system's judged need for V ampersand V (based in turn on its complexity and degree of required integrity); (2) the life-cycle phase; and (3) the system component being tested

  3. Guidelines for the verification and validation of expert system software and conventional software: Project summary. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Mirsky, S.M.; Hayes, J.E.; Miller, L.A. [Science Applications International Corp., McLean, VA (United States)

    1995-03-01

    This eight-volume report presents guidelines for performing verification and validation (V&V) on Artificial Intelligence (Al) systems with nuclear applications. The guidelines have much broader application than just expert systems; they are also applicable to object-oriented programming systems, rule-based systems, frame-based systems, model-based systems, neural nets, genetic algorithms, and conventional software systems. This is because many of the components of AI systems are implemented in conventional procedural programming languages, so there is no real distinction. The report examines the state of the art in verifying and validating expert systems. V&V methods traditionally applied to conventional software systems are evaluated for their applicability to expert systems. One hundred fifty-three conventional techniques are identified and evaluated. These methods are found to be useful for at least some of the components of expert systems, frame-based systems, and object-oriented systems. A taxonomy of 52 defect types and their delectability by the 153 methods is presented. With specific regard to expert systems, conventional V&V methods were found to apply well to all the components of the expert system with the exception of the knowledge base. The knowledge base requires extension of the existing methods. Several innovative static verification and validation methods for expert systems have been identified and are described here, including a method for checking the knowledge base {open_quotes}semantics{close_quotes} and a method for generating validation scenarios. Evaluation of some of these methods was performed both analytically and experimentally. A V&V methodology for expert systems is presented based on three factors: (1) a system`s judged need for V&V (based in turn on its complexity and degree of required integrity); (2) the life-cycle phase; and (3) the system component being tested.

  4. In vitro validation of a Pitot-based flow meter for the measurement of respiratory volume and flow in large animal anaesthesia.

    Science.gov (United States)

    Moens, Yves P S; Gootjes, Peter; Ionita, Jean-Claude; Heinonen, Erkki; Schatzmann, Urs

    2009-05-01

    To remodel and validate commercially available monitors and their Pitot tube-based flow sensors for use in large animals, using in vitro techniques. Prospective, in vitro experiment. Both the original and the remodelled sensor were studied with a reference flow generator. Measurements were taken of the static flow-pressure relationship and linearity of the flow signal. Sensor airway resistance was calculated. Following recalibration of the host monitor, volumes ranging from 1 to 7 L were generated by a calibration syringe, and bias and precision of spirometric volume was determined. Where manual recalibration was not available, a conversion factor for volume measurement was determined. The influence of gas composition mixture and peak flow on the conversion factor was studied. Both the original and the remodelled sensor showed similar static flow-pressure relationships and linearity of the flow signal. Mean bias (%) of displayed values compared with the reference volume of 3, 5 and 7 L varied between -0.4% and +2.4%, and this was significantly smaller than that for 1 L (4.8% to +5.0%). Conversion factors for 3, 5 and 7 L were very similar (mean 6.00 +/- 0.2, range 5.91-6.06) and were not significantly influenced by the gas mixture used. Increasing peak flow caused a small decrease in the conversion factor. Volume measurement error and conversion factors for inspiration and expiration were close to identity. The combination of the host monitor with the remodelled flow sensor allowed accurate in vitro measurement of flows and volumes in a range expected during large animal anaesthesia. This combination has potential as a reliable spirometric monitor for use during large animal anaesthesia.

  5. Comparative evaluation of respiratory-gated and ungated FDG-PET for target volume definition in radiotherapy treatment planning for pancreatic cancer.

    Science.gov (United States)

    Kishi, Takahiro; Matsuo, Yukinori; Nakamura, Akira; Nakamoto, Yuji; Itasaka, Satoshi; Mizowaki, Takashi; Togashi, Kaori; Hiraoka, Masahiro

    2016-08-01

    The purpose of this study was to evaluate the usefulness of respiratory-gated positron emission tomography (4D-PET) in pancreatic cancer radiotherapy treatment planning (RTTP). Fourteen patients with 18F-fluorodeoxyglucose (FDG)-avid pancreatic tumours were evaluated between December 2013 and March 2015. Two sets of volumes were contoured for the pancreatic tumour of each patient. The biological target volume in three-dimensional RTTP (BTV3D) was contoured using conventional respiratory un-gated PET. The BTV3D was then expanded using population-based margins to generate a series of internal target volume 3D (ITV3D) values. The ITV 4D (ITV4D) was contoured using 4D-PET. Each of the five phases of 4D-PET was used for 4D contouring, and the ITV4D was constructed by summing the volumes defined on the five individual 4D-PET images. The relative volumes and normalized volumetric overlap were computed between ITV3D and ITV4D. On average, the FDG-avid tumour volumes were 1.6 (range: 0.8-2.3) fold greater in the ITV4D than in the BTV3D. On average, the ITV3D values were 2.0 (range: 1.1-3.4) fold larger than the corresponding ITV4D values. The ITV generated from 4D-PET can be used to improve the accuracy or reduce normal tissue irradiation compared with conventional un-gated PET-based ITV. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. ABC/2 Method Does not Accurately Predict Cerebral Arteriovenous Malformation Volume.

    Science.gov (United States)

    Roark, Christopher; Vadlamudi, Venu; Chaudhary, Neeraj; Gemmete, Joseph J; Seinfeld, Joshua; Thompson, B Gregory; Pandey, Aditya S

    2018-02-01

    Stereotactic radiosurgery (SRS) is a treatment option for cerebral arteriovenous malformations (AVMs) to prevent intracranial hemorrhage. The decision to proceed with SRS is usually based on calculated nidal volume. Physicians commonly use the ABC/2 formula, based on digital subtraction angiography (DSA), when counseling patients for SRS. To determine whether AVM volume calculated using the ABC/2 method on DSA is accurate when compared to the exact volume calculated from thin-cut axial sections used for SRS planning. Retrospective search of neurovascular database to identify AVMs treated with SRS from 1995 to 2015. Maximum nidal diameters in orthogonal planes on DSA images were recorded to determine volume using ABC/2 formula. Nidal target volume was extracted from operative reports of SRS. Volumes were then compared using descriptive statistics and paired t-tests. Ninety intracranial AVMs were identified. Median volume was 4.96 cm3 [interquartile range (IQR) 1.79-8.85] with SRS planning methods and 6.07 cm3 (IQR 1.3-13.6) with ABC/2 methodology. Moderate correlation was seen between SRS and ABC/2 (r = 0.662; P ABC/2 (t = -3.2; P = .002). When AVMs were dichotomized based on ABC/2 volume, significant differences remained (t = 3.1, P = .003 for ABC/2 volume ABC/2 volume > 7 cm3). The ABC/2 method overestimates cerebral AVM volume when compared to volumetric analysis from SRS planning software. For AVMs > 7 cm3, the overestimation is even greater. SRS planning techniques were also significantly different than values derived from equations for cones and cylinders. Copyright © 2017 by the Congress of Neurological Surgeons

  7. LOX/hydrocarbon rocket engine analytical design methodology development and validation. Volume 2: Appendices

    Science.gov (United States)

    Niiya, Karen E.; Walker, Richard E.; Pieper, Jerry L.; Nguyen, Thong V.

    1993-05-01

    This final report includes a discussion of the work accomplished during the period from Dec. 1988 through Nov. 1991. The objective of the program was to assemble existing performance and combustion stability models into a usable design methodology capable of designing and analyzing high-performance and stable LOX/hydrocarbon booster engines. The methodology was then used to design a validation engine. The capabilities and validity of the methodology were demonstrated using this engine in an extensive hot fire test program. The engine used LOX/RP-1 propellants and was tested over a range of mixture ratios, chamber pressures, and acoustic damping device configurations. This volume contains time domain and frequency domain stability plots which indicate the pressure perturbation amplitudes and frequencies from approximately 30 tests of a 50K thrust rocket engine using LOX/RP-1 propellants over a range of chamber pressures from 240 to 1750 psia with mixture ratios of from 1.2 to 7.5. The data is from test configurations which used both bitune and monotune acoustic cavities and from tests with no acoustic cavities. The engine had a length of 14 inches and a contraction ratio of 2.0 using a 7.68 inch diameter injector. The data was taken from both stable and unstable tests. All combustion instabilities were spontaneous in the first tangential mode. Although stability bombs were used and generated overpressures of approximately 20 percent, no tests were driven unstable by the bombs. The stability instrumentation included six high-frequency Kistler transducers in the combustion chamber, a high-frequency Kistler transducer in each propellant manifold, and tri-axial accelerometers. Performance data is presented, both characteristic velocity efficiencies and energy release efficiencies, for those tests of sufficient duration to record steady state values.

  8. Streamlining Transportation Corridors Planning Processes and Validating the Application of Commercial Remote Sensing and Spatial Information (CRS-SI) Technologies for Environmental Impact Assessments

    Science.gov (United States)

    2008-02-05

    The new US DOT RITA program has selected MSU for addressing corridor planning and environmental assessment in new and innovative ways that can be compared to traditional approaches. Our primary focus is on the application and validation of new and in...

  9. Validated Alzheimer's Disease Risk Index (ANU-ADRI) is associated with smaller volumes in the default mode network in the early 60s.

    Science.gov (United States)

    Cherbuin, Nicolas; Shaw, Marnie E; Walsh, Erin; Sachdev, Perminder; Anstey, Kaarin J

    2017-12-14

    Strong evidence is available suggesting that effective reduction of exposure to demonstrated modifiable risk factors in mid-life or before could significantly decrease the incidence of Alzheimer's disease (AD) and delay its onset. A key ingredient to achieving this goal is the reliable identification of individuals at risk well before they develop clinical symptoms. The aim of this study was to provide further neuroimaging evidence of the effectiveness of a validated tool, the ANU Alzheimer's Disease Risk Index, for the assessment of future risk of cognitive decline. Participants were 461 (60-64 years, 48% female) community-living individuals free of dementia at baseline. Associations between risk estimates obtained with the ANU-ADRI, total and regional brain volumes including in the default mode network (DMN) measured at the same assessment and diagnosis of MCI/dementia over a 12-year follow-up were tested in a large sample of community-living individuals free of dementia at baseline. Higher risk estimates on the ANU-ADRI were associated with lower cortical gray matter and particularly in the DMN. Importantly, difference in participants with high and low risk scores explained 7-9% of the observed difference in gray matter volume. In this sample, every one additional risk point on the ANU-ADRI was associated with an 8% increased risk of developing MCI/dementia over a 12-year follow-up and this association was partly mediated by a sub-region of the DMN. Risk of cognitive decline assessed with a validated instrument is associated with gray matter volume, particularly in the DMN, a region known to be implicated in the pathological process of the disease.

  10. Developing and assessing accident management plans for nuclear power plants

    International Nuclear Information System (INIS)

    Hanson, D.J.; Johnson, S.P.; Blackman, H.S.; Stewart, M.A.

    1992-07-01

    This document is the second of a two-volume NUREG/CR that discusses development of accident management plans for nuclear power plants. The first volume (a) describes a four-phase approach for developing criteria that could be used for assessing the adequacy of accident management plans, (b) identifies the general attributes of accident management plans (Phase 1), (c) presents a prototype process for developing and implementing severe accident management plans (Phase 2), and (d) presents criteria that can be used to assess the adequacy of accident management plans. This volume (a) describes results from an evaluation of the capabilities of the prototype process to produce an accident management plan (Phase 3) and (b), based on these results and preliminary criteria included in NUREG/CR-5543, presents modifications to the criteria where appropriate

  11. The potential advantages of (18)FDG PET/CT-based target volume delineation in radiotherapy planning of head and neck cancer.

    Science.gov (United States)

    Moule, Russell N; Kayani, Irfan; Moinuddin, Syed A; Meer, Khalda; Lemon, Catherine; Goodchild, Kathleen; Saunders, Michele I

    2010-11-01

    This study investigated two fixed threshold methods to delineate the target volume using (18)FDG PET/CT before and during a course of radical radiotherapy in locally advanced squamous cell carcinoma of the head and neck. Patients were enrolled into the study between March 2006 and May 2008. (18)FDG PET/CT scans were carried out 72h prior to the start of radiotherapy and then at 10, 44 and 66Gy. Functional volumes were delineated according to the SUV Cut Off (SUVCO) (2.5, 3.0, 3.5, and 4.0bwg/ml) and percentage of the SUVmax (30%, 35%, 40%, 45%, and 50%) thresholds. The background (18)FDG uptake and the SUVmax within the volumes were also assessed. Primary and lymph node volumes for the eight patients significantly reduced with each increase in the delineation threshold (for example 2.5-3.0bwg/ml SUVCO) compared to the baseline threshold at each imaging point. There was a significant reduction in the volume (p⩽0.0001-0.01) after 36Gy compared to the 0Gy by the SUVCO method. There was a negative correlation between the SUVmax within the primary and lymph node volumes and delivered radiation dose (p⩽0.0001-0.011) but no difference in the SUV within the background reference region. The volumes delineated by the PTSUVmax method increased with the increase in the delivered radiation dose after 36Gy because the SUVmax within the region of interest used to define the edge of the volume was equal or less than the background (18)FDG uptake and the software was unable to effectively differentiate between tumour and background uptake. The changes in the target volumes delineated by the SUVCO method were less susceptible to background (18)FDG uptake compared to those delineated by the PTSUVmax and may be more helpful in radiotherapy planning. The best method and threshold have still to be determined within institutions, both nationally and internationally. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  12. Validation of an elastic registration technique to estimate anatomical lung modification in Non-Small-Cell Lung Cancer Tomotherapy

    International Nuclear Information System (INIS)

    Faggiano, Elena; Cattaneo, Giovanni M; Ciavarro, Cristina; Dell'Oca, Italo; Persano, Diego; Calandrino, Riccardo; Rizzo, Giovanna

    2011-01-01

    The study of lung parenchyma anatomical modification is useful to estimate dose discrepancies during the radiation treatment of Non-Small-Cell Lung Cancer (NSCLC) patients. We propose and validate a method, based on free-form deformation and mutual information, to elastically register planning kVCT with daily MVCT images, to estimate lung parenchyma modification during Tomotherapy. We analyzed 15 registrations between the planning kVCT and 3 MVCT images for each of the 5 NSCLC patients. Image registration accuracy was evaluated by visual inspection and, quantitatively, by Correlation Coefficients (CC) and Target Registration Errors (TRE). Finally, a lung volume correspondence analysis was performed to specifically evaluate registration accuracy in lungs. Results showed that elastic registration was always satisfactory, both qualitatively and quantitatively: TRE after elastic registration (average value of 3.6 mm) remained comparable and often smaller than voxel resolution. Lung volume variations were well estimated by elastic registration (average volume and centroid errors of 1.78% and 0.87 mm, respectively). Our results demonstrate that this method is able to estimate lung deformations in thorax MVCT, with an accuracy within 3.6 mm comparable or smaller than the voxel dimension of the kVCT and MVCT images. It could be used to estimate lung parenchyma dose variations in thoracic Tomotherapy

  13. Treatment planning evaluation of non-coplanar techniques for conformal radiotherapy of the prostate

    International Nuclear Information System (INIS)

    Bedford, James L.; Henrys, Anthony J.; Dearnaley, David P.; Khoo, Vincent S.

    2005-01-01

    Background and purpose: To evaluate the benefit of using non-coplanar treatment plans for irradiation of two different clinical treatment volumes: prostate only (PO) and the prostate plus seminal vesicles (PSV). Material and methods: An inverse planning algorithm was used to produce three-field, four-field, five-field and six-field non-coplanar treatment plans without intensity-modulation in ten patients. These were compared against a three-field coplanar plan. A dose of 74 Gy was prescribed to the isocentre. Plans were compared using the minimum dose to the planning target volume (PTV), maximum dose to the small bowel, and irradiated volumes of rectum, bladder and femoral head. Biological indices were also evaluated. Results: For the PO group, volume of rectum irradiated to 60 Gy (V 60 ) was 22.5±3.7% for the coplanar plan, and 21.5±5.3% for the five-field non-coplanar plan, which was the most beneficial (p=0.3). For the PSV group, the five-field non-coplanar plan was again the most beneficial. Rectal V 60 was in this case reduced from 41.5±10.4% for the coplanar plan to 35.2±9.3% for the non-coplanar plan (p=0.02). Conclusions: The use of non-coplanar beams in conformal prostate radiotherapy provides a small increase in rectal sparing, more significantly with PSV volumes than for PO volumes

  14. IMRT treatment plans and functional planning with functional lung imaging from 4D-CT for thoracic cancer patients

    Directory of Open Access Journals (Sweden)

    Huang Tzung-Chi

    2013-01-01

    Full Text Available Abstract Background and purpose Currently, the inhomogeneity of the pulmonary function is not considered when treatment plans are generated in thoracic cancer radiotherapy. This study evaluates the dose of treatment plans on highly-functional volumes and performs functional treatment planning by incorporation of ventilation data from 4D-CT. Materials and methods Eleven patients were included in this retrospective study. Ventilation was calculated using 4D-CT. Two treatment plans were generated for each case, the first one without the incorporation of the ventilation and the second with it. The dose of the first plans was overlapped with the ventilation and analyzed. Highly-functional regions were avoided in the second treatment plans. Results For small targets in the first plans (PTV  Conclusion Radiation treatments affect functional lung more seriously in large tumor cases. With compromise of dose to other critical organs, functional treatment planning to reduce dose in highly-functional lung volumes can be achieved

  15. Automated planning of breast radiotherapy using cone beam CT imaging

    International Nuclear Information System (INIS)

    Amit, Guy; Purdie, Thomas G.

    2015-01-01

    Purpose: Develop and clinically validate a methodology for using cone beam computed tomography (CBCT) imaging in an automated treatment planning framework for breast IMRT. Methods: A technique for intensity correction of CBCT images was developed and evaluated. The technique is based on histogram matching of CBCT image sets, using information from “similar” planning CT image sets from a database of paired CBCT and CT image sets (n = 38). Automated treatment plans were generated for a testing subset (n = 15) on the planning CT and the corrected CBCT. The plans generated on the corrected CBCT were compared to the CT-based plans in terms of beam parameters, dosimetric indices, and dose distributions. Results: The corrected CBCT images showed considerable similarity to their corresponding planning CTs (average mutual information 1.0±0.1, average sum of absolute differences 185 ± 38). The automated CBCT-based plans were clinically acceptable, as well as equivalent to the CT-based plans with average gantry angle difference of 0.99°±1.1°, target volume overlap index (Dice) of 0.89±0.04 although with slightly higher maximum target doses (4482±90 vs 4560±84, P < 0.05). Gamma index analysis (3%, 3 mm) showed that the CBCT-based plans had the same dose distribution as plans calculated with the same beams on the registered planning CTs (average gamma index 0.12±0.04, gamma <1 in 99.4%±0.3%). Conclusions: The proposed method demonstrates the potential for a clinically feasible and efficient online adaptive breast IMRT planning method based on CBCT imaging, integrating automation

  16. Development and validation of automatic tools for interactive recurrence analysis in radiation therapy: optimization of treatment algorithms for locally advanced pancreatic cancer.

    Science.gov (United States)

    Kessel, Kerstin A; Habermehl, Daniel; Jäger, Andreas; Floca, Ralf O; Zhang, Lanlan; Bendl, Rolf; Debus, Jürgen; Combs, Stephanie E

    2013-06-07

    In radiation oncology recurrence analysis is an important part in the evaluation process and clinical quality assurance of treatment concepts. With the example of 9 patients with locally advanced pancreatic cancer we developed and validated interactive analysis tools to support the evaluation workflow. After an automatic registration of the radiation planning CTs with the follow-up images, the recurrence volumes are segmented manually. Based on these volumes the DVH (dose volume histogram) statistic is calculated, followed by the determination of the dose applied to the region of recurrence and the distance between the boost and recurrence volume. We calculated the percentage of the recurrence volume within the 80%-isodose volume and compared it to the location of the recurrence within the boost volume, boost + 1 cm, boost + 1.5 cm and boost + 2 cm volumes. Recurrence analysis of 9 patients demonstrated that all recurrences except one occurred within the defined GTV/boost volume; one recurrence developed beyond the field border/outfield. With the defined distance volumes in relation to the recurrences, we could show that 7 recurrent lesions were within the 2 cm radius of the primary tumor. Two large recurrences extended beyond the 2 cm, however, this might be due to very rapid growth and/or late detection of the tumor progression. The main goal of using automatic analysis tools is to reduce time and effort conducting clinical analyses. We showed a first approach and use of a semi-automated workflow for recurrence analysis, which will be continuously optimized. In conclusion, despite the limitations of the automatic calculations we contributed to in-house optimization of subsequent study concepts based on an improved and validated target volume definition.

  17. Special nuclear material inventory sampling plans

    International Nuclear Information System (INIS)

    Vaccaro, H.; Goldman, A.

    1987-01-01

    Since their introduction in 1942, sampling inspection procedures have been common quality assurance practice. The U.S. Department of Energy (DOE) supports such sampling of special nuclear materials inventories. The DOE Order 5630.7 states, Operations Offices may develop and use statistically valid sampling plans appropriate for their site-specific needs. The benefits for nuclear facilities operations include reduced worker exposure and reduced work load. Improved procedures have been developed for obtaining statistically valid sampling plans that maximize these benefits. The double sampling concept is described and the resulting sample sizes for double sample plans are compared with other plans. An algorithm is given for finding optimal double sampling plans that assist in choosing the appropriate detection and false alarm probabilities for various sampling plans

  18. The planning target volume margins detected by cone-beam CT in head and neck cancer patients treated by image-guided intensity modulated radiotherapy

    International Nuclear Information System (INIS)

    Liu Jun; Chen Hong; Zhang Guoqiao; Chen Fei; Zhang Li

    2011-01-01

    Objective: To determine the planning target volume margins of head and neck cancers treated by image guided radiotherapy (IGRT). Methods: 464 sets cone beam computed tomography (CBCT) images before setup correction and 126 sets CBCT images after correction were obtained from 51 head and neck cancer patients treated by IGRT in our department. The systematic and random errors were evaluated by either online or offline correction through registering the CBCT images to the planning CT. The data was divided into 3 groups according to the online correction times. Results: The isocenter shift were 0.37 mm ± 2.37 mm, -0.43 mm ± 2.30 mm and 0.47 mm ± 2.65 mm in right-left (RL), anterior-posterior (AP) and superior-inferior (SI) directions respectively before correction, and it reduced to 0.08 mm ± 0.68 mm, -0.03 mm ± 0.74 mm and 0.03 mm ± 0.80 mm when evaluated by 126 sets corrected CBCT images. The planning target volume (PTV) margin from clinical target volume (CTV) before correction were: 6.41 mm, 6.15 mm and 7.10 mm based on two parameter model, and it reduced to 1.78 mm, 1.80 mm and 1.97 mm after correction. The PTV margins were 3.8 mm, 3.8 mm, 4.0 mm; 4.0 mm, 4.0 mm, 5.0 mm and 5.4 mm, 5.2 mm, 6.1 mm in RL, AP and SI respectively when online-correction times were more than 15 times, 11-15 times, 5-10 times. Conclusions: CBCT-based on online correction reduce the PTV margin for head and neck cancers treated by IGRT and ensure more precise dose delivery and less normal tissue complications. (authors)

  19. Systems Engineering Management Plan

    International Nuclear Information System (INIS)

    1994-01-01

    The purpose of this Monitored Retrievable Storage (MRS) Project Systems Engineering Management Plan (SEMP) is to define and establish the MRS Project Systems Engineering process that implements the approved policy and requirements of the Office of Civilian Radioactive Waste Management (OCRWM) for the US Department of Energy (DOE). This plan is Volume 5 of the MRS Project Management Plan (PMP). This plan provides the framework for implementation of systems engineering on the MRS Project consistent with DOE Order 4700.1, the OCRWM Program Management System Manual (PMSM), and the OCRWM Systems Engineering Management Plan (SEMP)

  20. [Preoperative imaging/operation planning for liver surgery].

    Science.gov (United States)

    Schoening, W N; Denecke, T; Neumann, U P

    2015-12-01

    The currently established standard for planning liver surgery is multistage contrast media-enhanced multidetector computed tomography (CM-CT), which as a rule enables an appropriate resection planning, e.g. a precise identification and localization of primary and secondary liver tumors as well as the anatomical relation to extrahepatic and/or intrahepatic vascular and biliary structures. Furthermore, CM-CT enables the measurement of tumor volume, total liver volume and residual liver volume after resection. Under the condition of normal liver function a residual liver volume of 25 % is nowadays considered sufficient and safe. Recent studies in patients with liver metastases of colorectal cancer showed a clear staging advantage of contrast media-enhanced magnetic resonance imaging (CM-MRI) versus CM-CT. In addition, most recent data showed that the use of liver-specific MRI contrast media further increases the sensitivity and specificity of detection of liver metastases. This imaging technology seems to lead closer to the ideal "one stop shopping" diagnostic tool in preoperative planning of liver resection.

  1. Validation of hippocampal volumes measured using a manual method and two automated methods (FreeSurfer and IBASPM) in chronic major depressive disorder

    Energy Technology Data Exchange (ETDEWEB)

    Tae, Woo Suk; Lee, Kang Uk; Nam, Eui-Cheol; Kim, Keun Woo [Kangwon National University College of Medicine, Neuroscience Research Institute, Kangwon (Korea); Kim, Sam Soo [Kangwon National University College of Medicine, Neuroscience Research Institute, Kangwon (Korea); Kangwon National University Hospital, Department of Radiology, Kangwon-do (Korea)

    2008-07-15

    To validate the usefulness of the packages available for automated hippocampal volumetry, we measured hippocampal volumes using one manual and two recently developed automated volumetric methods. The study included T1-weighted magnetic resonance imaging (MRI) of 21 patients with chronic major depressive disorder (MDD) and 20 normal controls. Using coronal turbo field echo (TFE) MRI with a slice thickness of 1.3 mm, the hippocampal volumes were measured using three methods: manual volumetry, surface-based parcellation using FreeSurfer, and individual atlas-based volumetry using IBASPM. In addition, the intracranial cavity volume (ICV) was measured manually. The absolute left hippocampal volume of the patients with MDD measured using all three methods was significantly smaller than the left hippocampal volume of the normal controls (manual P=0.029, FreeSurfer P=0.035, IBASPM P=0.018). After controlling for the ICV, except for the right hippocampal volume measured using FreeSurfer, both measured hippocampal volumes of the patients with MDD were significantly smaller than the measured hippocampal volumes of the normal controls (right manual P=0.019, IBASPM P=0.012; left manual P=0.003, FreeSurfer P=0.010, IBASPM P=0.002). In the intrarater reliability test, the intraclass correlation coefficients (ICCs) were all excellent (manual right 0.947, left 0.934; FreeSurfer right 1.000, left 1.000; IBASPM right 1.000, left 1.000). In the test of agreement between the volumetric methods, the ICCs were right 0.846 and left 0.848 (manual and FreeSurfer), and right 0.654 and left 0.717 (manual and IBASPM). The automated hippocampal volumetric methods showed good agreement with manual hippocampal volumetry, but the volume measured using FreeSurfer was 35% larger and the agreement was questionable with IBASPM. Although the automated methods could detect hippocampal atrophy in the patients with MDD, the results indicate that manual hippocampal volumetry is still the gold standard

  2. Validation of hippocampal volumes measured using a manual method and two automated methods (FreeSurfer and IBASPM) in chronic major depressive disorder

    International Nuclear Information System (INIS)

    Tae, Woo Suk; Lee, Kang Uk; Nam, Eui-Cheol; Kim, Keun Woo; Kim, Sam Soo

    2008-01-01

    To validate the usefulness of the packages available for automated hippocampal volumetry, we measured hippocampal volumes using one manual and two recently developed automated volumetric methods. The study included T1-weighted magnetic resonance imaging (MRI) of 21 patients with chronic major depressive disorder (MDD) and 20 normal controls. Using coronal turbo field echo (TFE) MRI with a slice thickness of 1.3 mm, the hippocampal volumes were measured using three methods: manual volumetry, surface-based parcellation using FreeSurfer, and individual atlas-based volumetry using IBASPM. In addition, the intracranial cavity volume (ICV) was measured manually. The absolute left hippocampal volume of the patients with MDD measured using all three methods was significantly smaller than the left hippocampal volume of the normal controls (manual P=0.029, FreeSurfer P=0.035, IBASPM P=0.018). After controlling for the ICV, except for the right hippocampal volume measured using FreeSurfer, both measured hippocampal volumes of the patients with MDD were significantly smaller than the measured hippocampal volumes of the normal controls (right manual P=0.019, IBASPM P=0.012; left manual P=0.003, FreeSurfer P=0.010, IBASPM P=0.002). In the intrarater reliability test, the intraclass correlation coefficients (ICCs) were all excellent (manual right 0.947, left 0.934; FreeSurfer right 1.000, left 1.000; IBASPM right 1.000, left 1.000). In the test of agreement between the volumetric methods, the ICCs were right 0.846 and left 0.848 (manual and FreeSurfer), and right 0.654 and left 0.717 (manual and IBASPM). The automated hippocampal volumetric methods showed good agreement with manual hippocampal volumetry, but the volume measured using FreeSurfer was 35% larger and the agreement was questionable with IBASPM. Although the automated methods could detect hippocampal atrophy in the patients with MDD, the results indicate that manual hippocampal volumetry is still the gold standard

  3. AUA Program Master Plan. Volume 1: Overview

    Science.gov (United States)

    1997-03-01

    The Office of Air Traffic Systems Development (AUA) Program Master Plan : summarizes the management, development approach, and status of products and : services provided by the AUA organization to fulfill its role in supporting : National Airspace Sy...

  4. Dynamics of glucagon secretion in mice and rats revealed using a validated sandwich ELISA for small sample volumes

    DEFF Research Database (Denmark)

    Albrechtsen, Nicolai Jacob Wewer; Kuhre, Rune Ehrenreich; Windeløv, Johanne Agerlin

    2016-01-01

    Glucagon is a metabolically important hormone, but many aspects of its physiology remain obscure, because glucagon secretion is difficult to measure in mice and rats due to methodological inadequacies. Here, we introduce and validate a low-volume, enzyme-linked immunosorbent glucagon assay...... according to current analytical guidelines, including tests of sensitivity, specificity, and accuracy, and compare it, using the Bland-Altman algorithm and size-exclusion chromatography, with three other widely cited assays. After demonstrating adequate performance of the assay, we measured glucagon...... and returning to basal levels at 6 min (mice) and 12 min (rats). d-Mannitol (osmotic control) was without effect. Ketamine/xylazine anesthesia in mice strongly attenuated (P assay. In conclusion, dynamic analysis...

  5. Computer-assisted operational planning for pediatric abdominal surgery. 3D-visualized MRI with volume rendering; Die computerassistierte Operationsplanung in der Abdominalchirurgie des Kindes. 3D-Visualisierung mittels ''volume rendering'' in der MRT

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, P.; Holland-Cunz, S.; Waag, K.L. [Universitaetsklinikum Heidelberg (Germany). Kinderchirurgie; Troeger, J. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Schenk, J.P. [Universitaetsklinikum Heidelberg, (Germany). Paediatrische Radiologie; Universitaetsklinikum, Paediatrische Radiologie, Heidelberg (Germany)

    2006-08-15

    Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this. A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning. (orig.) [German] Komplexe Operationen bei ausgepraegten pathologischen Veraenderungen anatomischer Strukturen des kindlichen Abdomens benoetigen eine exakte Operationsvorbereitung. 3D-Visualisierung und computerassistierte Operationsplanung anhand von CT-Daten finden fuer schwierige chirurgische Eingriffe bei Erwachsenen in zunehmendem Masse Anwendung. Aus strahlenhygienischen Gruenden und bei besserer Weichteildifferenzierung ist jedoch neben der Sonographie die Magnetresonanztomographie (MRT) bei Kindern das Diagnostikum der Wahl. Die 3D-Visualisierung dieser MRT-Daten ist dabei jedoch aufgrund vielfaeltiger Schwierigkeiten bisher nicht durchgefuehrt worden, obwohl sich das Gebiet embryonaler Fehlbildungen und Tumoren geradezu anbietet. Vorgestellt wird eine weiterentwickelte und an die Fragestellungen der abdominellen Kinderchirurgie angepasste, sehr leistungsstarke raycastingbasierte 3D-volume-rendering-Software (VG Studio Max 1

  6. Improvement of internal tumor volumes of non-small cell lung cancer patients for radiation treatment planning using interpolated average CT in PET/CT.

    Directory of Open Access Journals (Sweden)

    Yao-Ching Wang

    Full Text Available Respiratory motion causes uncertainties in tumor edges on either computed tomography (CT or positron emission tomography (PET images and causes misalignment when registering PET and CT images. This phenomenon may cause radiation oncologists to delineate tumor volume inaccurately in radiotherapy treatment planning. The purpose of this study was to analyze radiology applications using interpolated average CT (IACT as attenuation correction (AC to diminish the occurrence of this scenario. Thirteen non-small cell lung cancer patients were recruited for the present comparison study. Each patient had full-inspiration, full-expiration CT images and free breathing PET images by an integrated PET/CT scan. IACT for AC in PET(IACT was used to reduce the PET/CT misalignment. The standardized uptake value (SUV correction with a low radiation dose was applied, and its tumor volume delineation was compared to those from HCT/PET(HCT. The misalignment between the PET(IACT and IACT was reduced when compared to the difference between PET(HCT and HCT. The range of tumor motion was from 4 to 17 mm in the patient cohort. For HCT and PET(HCT, correction was from 72% to 91%, while for IACT and PET(IACT, correction was from 73% to 93% (*p<0.0001. The maximum and minimum differences in SUVmax were 0.18% and 27.27% for PET(HCT and PET(IACT, respectively. The largest percentage differences in the tumor volumes between HCT/PET and IACT/PET were observed in tumors located in the lowest lobe of the lung. Internal tumor volume defined by functional information using IACT/PET(IACT fusion images for lung cancer would reduce the inaccuracy of tumor delineation in radiation therapy planning.

  7. The rationale and technique of staged-volume arteriovenous malformation radiosurgery

    International Nuclear Information System (INIS)

    Pollock, Bruce E.; Kline, Robert W.; Stafford, Scott L.; Foote, Robert L.; Schomberg, Paula J.

    2000-01-01

    Purpose: Stereotactic radiosurgery is an effective management strategy for properly selected arteriovenous malformation (AVM) patients. However, the risk of postradiosurgical radiation-related injury generally limits this procedure to patients with AVMs of an average diameter of 3 cm or less. Radiosurgery of large AVMs in a planned staged fashion was undertaken to limit the radiation exposure to the surrounding normal brain. Methods and Materials: Between April 1997 and December 1999, 10 patients with a median AVM volume of 17.4 cm 3 (range, 7.4-53.3 cm 3 ) underwent staged-volume radiosurgery (23 procedures). At the first radiosurgical procedure, the total volume of the AVM is estimated and a dose plan calculated that covers 10 cm 3 -15 cm 3 , or one-half the nidus volume if the AVM is critically located (brainstem, thalamus, or basal ganglia). At 6-month intervals thereafter, radiosurgery was repeated to different portions of the AVM with the previous dose plan(s) being re-created utilizing intracranial landmarks to minimize radiation overlap. Radiosurgical procedures were continued until the entire malformation has been irradiated. Results: The radiation dosimetry of staged-volume AVM radiosurgery was compared to hypothetical single-session procedures for the 10 patients. Staged-volume radiosurgery decreased the 12-Gy volume by an average of 11.1% (range, 4.9-21%) (p < 0.001). The non-AVM 12-Gy volume was reduced by an average of 27.2% (range, 12.5-51.3%) (p < 0.001). Discussion: Staged-volume radiosurgery of large AVMs results in less radiation exposure to the adjacent brain. Further follow-up is needed to determine whether this technique provides a high rate of AVM obliteration while maintaining an acceptable rate of radiation-related complications

  8. SU-F-BRF-10: Deformable MRI to CT Validation Employing Same Day Planning MRI for Surrogate Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Padgett, K; Stoyanova, R; Johnson, P; Dogan, N; Pollack, A [University of Miami School of Medicine, Miami, FL (United States); Piper, J; Javorek, A [MIM Software, Inc., Beachwood, OH (United States)

    2014-06-15

    Purpose: To compare rigid and deformable registrations of the prostate in the multi-modality setting (diagnostic-MRI to planning-CT) by utilizing a planning-MRI as a surrogate. The surrogate allows for the direct quantitative analysis which can be difficult in the multi-modality domain where intensity mapping differs. Methods: For ten subjects, T2 fast-spin-echo images were acquired at two different time points, the first several weeks prior to planning (diagnostic-MRI) and the second on the same day in which the planning CT was collected (planning-MRI). Significant effort in patient positioning and bowel/bladder preparation was undertaken to minimize distortion of the prostate in all datasets. The diagnostic-MRI was deformed to the planning-CT utilizing a commercially available deformable registration algorithm synthesized from local registrations. The deformed MRI was then rigidly aligned to the planning MRI which was used as the surrogate for the planning-CT. Agreement between the two MRI datasets was scored using intensity based metrics including Pearson correlation and normalized mutual information, NMI. A local analysis was performed by looking only within the prostate, proximal seminal vesicles, penile bulb and combined areas. A similar method was used to assess a rigid registration between the diagnostic-MRI and planning-CT. Results: Utilizing the NMI, the deformable registrations were superior to the rigid registrations in 9 of 10 cases demonstrating a 15.94% improvement (p-value < 0.001) within the combined area. The Pearson correlation showed similar results with the deformable registration superior in the same number of cases and demonstrating a 6.97% improvement (p-value <0.011). Conclusion: Validating deformable multi-modality registrations using spatial intensity based metrics is difficult due to the inherent differences in intensity mapping. This population provides an ideal testing ground for MRI to CT deformable registrations by obviating the need

  9. X-ray volume imaging in bladder radiotherapy verification

    International Nuclear Information System (INIS)

    Henry, Ann M.; Stratford, Julia; McCarthy, Claire; Davies, Julie; Sykes, Jonathan R.; Amer, Ali; Marchant, Tom; Cowan, Richard; Wylie, James; Logue, John; Livsey, Jacqueline; Khoo, Vincent S.; Moore, Chris; Price, Pat

    2006-01-01

    Purpose: To assess the clinical utility of X-ray volume imaging (XVI) for verification of bladder radiotherapy and to quantify geometric error in bladder radiotherapy delivery. Methods and Materials: Twenty subjects undergoing conformal bladder radiotherapy were recruited. X-ray volume images and electronic portal images (EPIs) were acquired for the first 5 fractions and then once weekly. X-ray volume images were co-registered with the planning computed tomography scan and clinical target volume coverage assessed in three dimensions (3D). Interfraction bladder volume change was described by quantifying changes in bladder volume with time. Bony setup errors were compared from both XVI and EPI. Results: The bladder boundary was clearly visible on coronal XVI views in nearly all images, allowing accurate 3D treatment verification. In 93.5% of imaged fractions, the clinical target volume was within the planning target volume. Most subjects displayed consistent bladder volumes, but 25% displayed changes that could be predicted from the first three XVIs. Bony setup errors were similar whether calculated from XVI or EPI. Conclusions: Coronal XVI can be used to verify 3D bladder radiotherapy delivery. Image-guided interventions to reduce geographic miss and normal tissue toxicity are feasible with this technology

  10. Guidelines for the verification and validation of expert system software and conventional software. Volume 1: Project summary. Final report

    International Nuclear Information System (INIS)

    Miller, L.A.; Hayes, J.E.; Mirsky, S.M.

    1995-05-01

    This eight-volume report presents guidelines for performing verification and validation (V ampersand V) on Artificial Intelligence (AI) systems with nuclear applications. The guidelines have much broader application than just expert systems; they are also applicable to object-oriented programming systems, rule-based systems, frame-based systems, model-based systems, neural nets, genetic algorithms, and conventional software systems. This is because many of the components of AI systems are implemented in conventional procedural programming languages, so there is no real distinction. The report examines the state of the art in verifying and validating expert systems. V ampersand V methods traditionally applied to conventional software systems are evaluated for their applicability to expert systems. One hundred fifty-three conventional techniques are identified and evaluated. These methods are found to be useful for at least some of the components of expert systems, frame-based systems, and object-oriented systems. A taxonomy of 52 defect types and their delectability by the 153 methods is presented. With specific regard to expert systems, conventional V ampersand V methods were found to apply well to all the components of the expert system with the exception of the knowledge base. The knowledge base requires extension of the existing methods. Several innovative static verification and validation methods for expert systems have been identified and are described here, including a method for checking the knowledge base open-quotes semanticsclose quotes and a method for generating validation scenarios. Evaluation of some of these methods was performed both analytically and experimentally

  11. Integration of second cancer risk calculations in a radiotherapy treatment planning system

    International Nuclear Information System (INIS)

    Hartmann, M; Schneider, U

    2014-01-01

    Second cancer risk in patients, in particular in children, who were treated with radiotherapy is an important side effect. It should be minimized by selecting an appropriate treatment plan for the patient. The objectives of this study were to integrate a risk model for radiation induced cancer into a treatment planning system which allows to judge different treatment plans with regard to second cancer induction and to quantify the potential reduction in predicted risk. A model for radiation induced cancer including fractionation effects which is valid for doses in the radiotherapy range was integrated into a treatment planning system. From the three-dimensional (3D) dose distribution the 3D-risk equivalent dose (RED) was calculated on an organ specific basis. In addition to RED further risk coefficients like OED (organ equivalent dose), EAR (excess absolute risk) and LAR (lifetime attributable risk) are computed. A risk model for radiation induced cancer was successfully integrated in a treatment planning system. Several risk coefficients can be viewed and used to obtain critical situations were a plan can be optimised. Risk-volume-histograms and organ specific risks were calculated for different treatment plans and were used in combination with NTCP estimates for plan evaluation. It is concluded that the integration of second cancer risk estimates in a commercial treatment planning system is feasible. It can be used in addition to NTCP modelling for optimising treatment plans which result in the lowest possible second cancer risk for a patient.

  12. Guidelines for the verification and validation of expert system software and conventional software: Survey and documentation of expert system verification and validation methodologies. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Groundwater, E.H.; Miller, L.A.; Mirsky, S.M. [Science Applications International Corp., McLean, VA (United States)

    1995-03-01

    This report is the third volume in the final report for the Expert System Verification and Validation (V&V) project which was jointly sponsored by the Nuclear Regulatory Commission and the Electric Power Research Institute. The ultimate objective is the formulation of guidelines for the V&V of expert systems for use in nuclear power applications. The purpose of this activity was to survey and document techniques presently in use for expert system V&V. The survey effort included an extensive telephone interviewing program, site visits, and a thorough bibliographic search and compilation. The major finding was that V&V of expert systems is not nearly as established or prevalent as V&V of conventional software systems. When V&V was used for expert systems, it was almost always at the system validation stage after full implementation and integration usually employing the non-systematic dynamic method of {open_quotes}ad hoc testing.{close_quotes} There were few examples of employing V&V in the early phases of development and only weak sporadic mention of the possibilities in the literature. There is, however, a very active research area concerning the development of methods and tools to detect problems with, particularly, rule-based expert systems. Four such static-testing methods were identified which were not discovered in a comprehensive review of conventional V&V methods in an earlier task.

  13. Long-term research plan for human factors affecting safeguards at nuclear power plants. Volume 1. Summary and users' guide. Vol. 1

    International Nuclear Information System (INIS)

    O'Brien, J.N.; Fainberg, A.

    1984-04-01

    This report presents a long-term research plan for addressing human factors which can adversely affect safeguards at nuclear power plants. It was developed in order to prioritize and propose research for NRC in regulating power plant safeguards. Research efforts addressing human factors in safeguards were developed and prioritized according to the importance of human factors areas. Research was also grouped to take advantage of common research approaches and data sources where appropriate. Four main program elements emerged from the analysis, namely (1) Training and Performance Evaluation, (2) Organizational Factors, (3) Man-Machine Interface, and (4) Trustworthiness and Reliability. Within each program element, projects are proposed with results and information flowing between program elements where useful. An overall research plan was developed for a 4-year period and it would lead ultimately to regulatory activities including rulemaking, regulatory guides, and technical bases for regulatory action. The entire plan is summarized in Volume 1 of this report

  14. Some aspects of the relation between the volume of prostate carcinoma and its interstitial BT volume

    International Nuclear Information System (INIS)

    Zivanovic, A; Babic, J; Erak, M.; Dabic, K.; Donat, D.; Kuzmanovic, Z.; Savic, D.

    1996-01-01

    It is a fact that the volume achieved by the interstitial procedure during the brachy treatment of prostate carcinoma is several times smaller than the one we get in, so called, external beam therapy. Furthermore, interstitial brachytherapy offers the possibility to apply large dose into the small volume. However, both dose and volume are at the same time the factors that limit the therapy and the main technical offenders in case of therapy failure. We tried, through a strong individual approach, to compare the volume obtained mathematically and the volume obtained by planning (TPS). By means of clinical examinations and CT scans we conceived a prostate as half of the volume of ellipsoid under one condition only: the magnification of the prostate has to be a symmetrical one. Finally, we applied the following formula: V prostate=(1(2)) ellipsoid=2.09·a/2·e/2·b where a=(1(2)) of sagittal diameter b=prostate height (from apex to base) c=(1(2)) of transversal diameter Each volume obtained in the this way has been taken into account during the application of interstitial needles which in their own way and in accordance to a routine planning, form an active therapeutic interstitial volume. The obtained data showed differences between these two types of volumes. From the statistical point of view, mathematically obtained volume of CV was 16.6% while interstitial volume was 14.9%. T-test was 3.9. On average, mathematical volume is lower and this balance is a desirable one because it means a smaller possibility for potential positive biopsy as a result of a 'rest' tumour. If on the other hand, positive biopsy is a result of the 'rest' tumour and our interpretation has been a contradictory one, precious time with disappointing results will be lost. At the end we achieved: a) double checked control of the embraced volumes, b) stronger fulcrum for the next step: dose-fraction balance

  15. IMRT treatment planning-A comparative inter-system and inter-centre planning exercise of the ESTRO QUASIMODO group

    International Nuclear Information System (INIS)

    Bohsung, Joerg; Gillis, Sofie; Arrans, Rafael; Bakai, Annemarie; De Wagter, Carlos; Knoeoes, Tommy; Mijnheer, Ben J.; Paiusco, Marta; Perrin, Bruce A.; Welleweerd, Hans; Williams, Peter

    2005-01-01

    Background and purpose: The purpose of this work was a comparison of realistic IMRT plans based on the same CT-image data set and a common predefined set of dose objectives for the planning target volume and the organs at risk. This work was part of the larger European QUASIMODO IMRT verification project. Materials and methods: Eleven IMRT plans were produced by nine different European groups, each applying a representative set of clinically used IMRT treatment planning systems. The plans produced were to be deliverable in a clinically acceptable treatment time with the local technical equipment. All plans were characterized using a set of different quality measures such as dose-volume histograms, number of monitor units and treatment time. Results: Only one plan was able to fulfil all dose objectives strictly; six plans failed some of the objectives but were still considered to be clinically acceptable; four plans were not able to reach the objectives. Additional quality scores such as the number of monitor units and treatment time showed large variations, which mainly depend on the delivery technique. Conclusion: The presented planning study showed that with nearly all presently available IMRT planning and delivery systems comparable dose distributions could be achieved if the planning goals are clearly defined in advance

  16. Impact of target volume coverage with Radiation Therapy Oncology Group (RTOG) 98-05 guidelines for transrectal ultrasound guided permanent Iodine-125 prostate implants

    International Nuclear Information System (INIS)

    Horwitz, Eric M.; Mitra, Raj K.; Uzzo, Robert G.; Das, Indra J.; Pinover, Wayne H.; Hanlon, Alexandra L.; McNeeley, Shawn W.; Hanks, Gerald E.

    2003-01-01

    Purpose: Despite the wide use of permanent prostate implants for the treatment of early stage prostate cancer, there is no consensus for optimal pre-implant planning guidelines that results in maximal post-implant target coverage. The purpose of this study was to compare post-implant target volume coverage and dosimetry between patients treated before and after Radiation Therapy Oncology Group (RTOG) 98-05 guidelines were adopted using several dosimetric endpoints. Materials and methods: Ten consecutively treated patients before the adoption of the RTOG 98-05 planning guidelines were compared with ten consecutively treated patients after implementation of the guidelines. Pre-implant planning for patients treated pre-RTOG was based on the clinical target volume (CTV) defined by the pre-implant TRUS definition of the prostate. The CTV was expanded in each dimension according to RTOG 98-05 and defined as the planning target volume. The evaluation target volume was defined as the post-implant computed tomography definition of the prostate based on RTOG 98-05 protocol recommendations. Implant quality indicators included V 100 , V 90 , V 100 , and Coverage Index (CI). Results: The pre-RTOG median V 100 , V 90 , D 90 , and CI values were 82.8, 88.9%, 126.5 Gy, and 17.1, respectively. The median post-RTOG V 100 , V 90 , D 90 , and CI values were 96.0, 97.8%, 169.2 Gy, and 4.0, respectively. These differences were all statistically significant. Conclusions: Implementation of the RTOG 98-05 implant planning guidelines has increased coverage of the prostate by the prescription isodose lines compared with our previous technique, as indicated by post-implant dosimetry indices such as V 100 , V 90 , D 90 . The CI was also improved significantly with the protocol guidelines. Our data confirms the validity of the RTOG 98-05 implant guidelines for pre-implant planning as it relates to enlargement of the CTV to ensure adequate margin between the CTV and the prescription isodose

  17. Integrated operations plan for the MFTF-B Mirror Fusion Test Facility. Volume II. Integrated operations plan

    Energy Technology Data Exchange (ETDEWEB)

    1981-12-01

    This document defines an integrated plan for the operation of the Lawrence Livermore National Laboratory (LLNL) Mirror Fusion Test Facility (MFTF-B). The plan fulfills and further delineates LLNL policies and provides for accomplishing the functions required by the program. This plan specifies the management, operations, maintenance, and engineering support responsibilities. It covers phasing into sustained operations as well as the sustained operations themselves. Administrative and Plant Engineering support, which are now being performed satisfactorily, are not part of this plan unless there are unique needs.

  18. Integrated operations plan for the MFTF-B Mirror Fusion Test Facility. Volume II. Integrated operations plan

    International Nuclear Information System (INIS)

    1981-12-01

    This document defines an integrated plan for the operation of the Lawrence Livermore National Laboratory (LLNL) Mirror Fusion Test Facility (MFTF-B). The plan fulfills and further delineates LLNL policies and provides for accomplishing the functions required by the program. This plan specifies the management, operations, maintenance, and engineering support responsibilities. It covers phasing into sustained operations as well as the sustained operations themselves. Administrative and Plant Engineering support, which are now being performed satisfactorily, are not part of this plan unless there are unique needs

  19. SU-F-T-340: Direct Editing of Dose Volume Histograms: Algorithms and a Unified Convex Formulation for Treatment Planning with Dose Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Ungun, B [Stanford University, Stanford, CA (United States); Stanford University School of Medicine, Stanford, CA (United States); Fu, A; Xing, L [Stanford University School of Medicine, Stanford, CA (United States); Boyd, S [Stanford University, Stanford, CA (United States)

    2016-06-15

    Purpose: To develop a procedure for including dose constraints in convex programming-based approaches to treatment planning, and to support dynamic modification of such constraints during planning. Methods: We present a mathematical approach that allows mean dose, maximum dose, minimum dose and dose volume (i.e., percentile) constraints to be appended to any convex formulation of an inverse planning problem. The first three constraint types are convex and readily incorporated. Dose volume constraints are not convex, however, so we introduce a convex restriction that is related to CVaR-based approaches previously proposed in the literature. To compensate for the conservatism of this restriction, we propose a new two-pass algorithm that solves the restricted problem on a first pass and uses this solution to form exact constraints on a second pass. In another variant, we introduce slack variables for each dose constraint to prevent the problem from becoming infeasible when the user specifies an incompatible set of constraints. We implement the proposed methods in Python using the convex programming package cvxpy in conjunction with the open source convex solvers SCS and ECOS. Results: We show, for several cases taken from the clinic, that our proposed method meets specified constraints (often with margin) when they are feasible. Constraints are met exactly when we use the two-pass method, and infeasible constraints are replaced with the nearest feasible constraint when slacks are used. Finally, we introduce ConRad, a Python-embedded free software package for convex radiation therapy planning. ConRad implements the methods described above and offers a simple interface for specifying prescriptions and dose constraints. Conclusion: This work demonstrates the feasibility of using modifiable dose constraints in a convex formulation, making it practical to guide the treatment planning process with interactively specified dose constraints. This work was supported by the

  20. SU-F-T-340: Direct Editing of Dose Volume Histograms: Algorithms and a Unified Convex Formulation for Treatment Planning with Dose Constraints

    International Nuclear Information System (INIS)

    Ungun, B; Fu, A; Xing, L; Boyd, S

    2016-01-01

    Purpose: To develop a procedure for including dose constraints in convex programming-based approaches to treatment planning, and to support dynamic modification of such constraints during planning. Methods: We present a mathematical approach that allows mean dose, maximum dose, minimum dose and dose volume (i.e., percentile) constraints to be appended to any convex formulation of an inverse planning problem. The first three constraint types are convex and readily incorporated. Dose volume constraints are not convex, however, so we introduce a convex restriction that is related to CVaR-based approaches previously proposed in the literature. To compensate for the conservatism of this restriction, we propose a new two-pass algorithm that solves the restricted problem on a first pass and uses this solution to form exact constraints on a second pass. In another variant, we introduce slack variables for each dose constraint to prevent the problem from becoming infeasible when the user specifies an incompatible set of constraints. We implement the proposed methods in Python using the convex programming package cvxpy in conjunction with the open source convex solvers SCS and ECOS. Results: We show, for several cases taken from the clinic, that our proposed method meets specified constraints (often with margin) when they are feasible. Constraints are met exactly when we use the two-pass method, and infeasible constraints are replaced with the nearest feasible constraint when slacks are used. Finally, we introduce ConRad, a Python-embedded free software package for convex radiation therapy planning. ConRad implements the methods described above and offers a simple interface for specifying prescriptions and dose constraints. Conclusion: This work demonstrates the feasibility of using modifiable dose constraints in a convex formulation, making it practical to guide the treatment planning process with interactively specified dose constraints. This work was supported by the

  1. A fully automatic approach for multimodal PET and MR image segmentation in gamma knife treatment planning.

    Science.gov (United States)

    Rundo, Leonardo; Stefano, Alessandro; Militello, Carmelo; Russo, Giorgio; Sabini, Maria Gabriella; D'Arrigo, Corrado; Marletta, Francesco; Ippolito, Massimo; Mauri, Giancarlo; Vitabile, Salvatore; Gilardi, Maria Carla

    2017-06-01

    Nowadays, clinical practice in Gamma Knife treatments is generally based on MRI anatomical information alone. However, the joint use of MRI and PET images can be useful for considering both anatomical and metabolic information about the lesion to be treated. In this paper we present a co-segmentation method to integrate the segmented Biological Target Volume (BTV), using [ 11 C]-Methionine-PET (MET-PET) images, and the segmented Gross Target Volume (GTV), on the respective co-registered MR images. The resulting volume gives enhanced brain tumor information to be used in stereotactic neuro-radiosurgery treatment planning. GTV often does not match entirely with BTV, which provides metabolic information about brain lesions. For this reason, PET imaging is valuable and it could be used to provide complementary information useful for treatment planning. In this way, BTV can be used to modify GTV, enhancing Clinical Target Volume (CTV) delineation. A novel fully automatic multimodal PET/MRI segmentation method for Leksell Gamma Knife ® treatments is proposed. This approach improves and combines two computer-assisted and operator-independent single modality methods, previously developed and validated, to segment BTV and GTV from PET and MR images, respectively. In addition, the GTV is utilized to combine the superior contrast of PET images with the higher spatial resolution of MRI, obtaining a new BTV, called BTV MRI . A total of 19 brain metastatic tumors, undergone stereotactic neuro-radiosurgery, were retrospectively analyzed. A framework for the evaluation of multimodal PET/MRI segmentation is also presented. Overlap-based and spatial distance-based metrics were considered to quantify similarity concerning PET and MRI segmentation approaches. Statistics was also included to measure correlation among the different segmentation processes. Since it is not possible to define a gold-standard CTV according to both MRI and PET images without treatment response assessment

  2. Testing the new ICRU 62 'Planning Organ at Risk Volume' concept for the rectum

    International Nuclear Information System (INIS)

    Muren, Ludvig Paul; Karlsdottir, Asa; Kvinnsland, Yngve; Wentzel-Larsen, Tore; Dahl, Olav

    2005-01-01

    Background and purpose: To study the impact of the new ICRU 62 'Planning organ at Risk Volume' (PRV) concept on the relationship between rectum dose-volume histogram (DVH) data and toxicity. Patients and methods: The acute gastro-intestinal (GI) RTOG toxicity in 127 prostate cancer patients prescribed a total dose of 70 Gy with conformal irradiation to either the prostate, the prostate and seminal vesicles or the whole pelvis (initial 50 Gy only) were analysed. DVHs were derived for the rectum only and for rectum extended with six PRV margin sets (narrow/intermediate/wide; anterior/anterior and posterior). The data was analysed using permutation tests, logistic regression and effective uniform dose (EUD) calculations. Results: Acute Grade 2 GI toxicity was seen in 22 of 127 cases (17%). Permutation tests showed that the difference between DVHs for patients with and without Grade 2 effects was significant, both for rectum only and rectum PRVs (P-value range: 0.02-0.04), with generally lower P-values for the PRVs. In the logistic regression, the fractional DVH variables (i.e. volumes) were significantly related to toxicity, with approximately 2-3 times as many significant dose levels for the PRVs as for rectum only. E.g. with wide anterior and posterior margins (16 and 11 mm, respectively) the relation was significant at 26 different dose levels (6-7, 13-14, 35-43, 60-71 and 73 Gy), compared to nine levels (38-40, 43-44 and 71-74 Gy) for rectum only. EUDs were significantly different for patients with and without Grade 2 effects both for rectum only and the PRVs (95% confidence interval for EUD increase with Grade 2 effects: 0.1-3.1 Gy). Conclusions: All statistical methods applied indicated a small, but definite difference in DVH parameters between patients with versus those without Grade 2 effects. The difference was most pronounced when margins of 16 mm anterior and 11 mm posterior were applied

  3. Predicting objective function weights from patient anatomy in prostate IMRT treatment planning

    International Nuclear Information System (INIS)

    Lee, Taewoo; Hammad, Muhannad; Chan, Timothy C. Y.; Craig, Tim; Sharpe, Michael B.

    2013-01-01

    Purpose: Intensity-modulated radiation therapy (IMRT) treatment planning typically combines multiple criteria into a single objective function by taking a weighted sum. The authors propose a statistical model that predicts objective function weights from patient anatomy for prostate IMRT treatment planning. This study provides a proof of concept for geometry-driven weight determination. Methods: A previously developed inverse optimization method (IOM) was used to generate optimal objective function weights for 24 patients using their historical treatment plans (i.e., dose distributions). These IOM weights were around 1% for each of the femoral heads, while bladder and rectum weights varied greatly between patients. A regression model was developed to predict a patient's rectum weight using the ratio of the overlap volume of the rectum and bladder with the planning target volume at a 1 cm expansion as the independent variable. The femoral head weights were fixed to 1% each and the bladder weight was calculated as one minus the rectum and femoral head weights. The model was validated using leave-one-out cross validation. Objective values and dose distributions generated through inverse planning using the predicted weights were compared to those generated using the original IOM weights, as well as an average of the IOM weights across all patients. Results: The IOM weight vectors were on average six times closer to the predicted weight vectors than to the average weight vector, usingl 2 distance. Likewise, the bladder and rectum objective values achieved by the predicted weights were more similar to the objective values achieved by the IOM weights. The difference in objective value performance between the predicted and average weights was statistically significant according to a one-sided sign test. For all patients, the difference in rectum V54.3 Gy, rectum V70.0 Gy, bladder V54.3 Gy, and bladder V70.0 Gy values between the dose distributions generated by the

  4. Multiyear Plan for Validation of EnergyPlus Multi-Zone HVAC System Modeling using ORNL's Flexible Research Platform

    Energy Technology Data Exchange (ETDEWEB)

    Im, Piljae [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bhandari, Mahabir S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); New, Joshua Ryan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-10-01

    This document describes the Oak Ridge National Laboratory (ORNL) multiyear experimental plan for validation and uncertainty characterization of whole-building energy simulation for a multi-zone research facility using a traditional rooftop unit (RTU) as a baseline heating, ventilating, and air conditioning (HVAC) system. The project’s overarching objective is to increase the accuracy of energy simulation tools by enabling empirical validation of key inputs and algorithms. Doing so is required to inform the design of increasingly integrated building systems and to enable accountability for performance gaps between design and operation of a building. The project will produce documented data sets that can be used to validate key functionality in different energy simulation tools and to identify errors and inadequate assumptions in simulation engines so that developers can correct them. ASHRAE Standard 140, Method of Test for the Evaluation of Building Energy Analysis Computer Programs (ASHRAE 2004), currently consists primarily of tests to compare different simulation programs with one another. This project will generate sets of measured data to enable empirical validation, incorporate these test data sets in an extended version of Standard 140, and apply these tests to the Department of Energy’s (DOE) EnergyPlus software (EnergyPlus 2016) to initiate the correction of any significant deficiencies. The fitness-for-purpose of the key algorithms in EnergyPlus will be established and demonstrated, and vendors of other simulation programs will be able to demonstrate the validity of their products. The data set will be equally applicable to validation of other simulation engines as well.

  5. Reachable volume RRT

    KAUST Repository

    McMahon, Troy

    2015-05-01

    © 2015 IEEE. Reachable volumes are a new technique that allows one to efficiently restrict sampling to feasible/reachable regions of the planning space even for high degree of freedom and highly constrained problems. However, they have so far only been applied to graph-based sampling-based planners. In this paper we develop the methodology to apply reachable volumes to tree-based planners such as Rapidly-Exploring Random Trees (RRTs). In particular, we propose a reachable volume RRT called RVRRT that can solve high degree of freedom problems and problems with constraints. To do so, we develop a reachable volume stepping function, a reachable volume expand function, and a distance metric based on these operations. We also present a reachable volume local planner to ensure that local paths satisfy constraints for methods such as PRMs. We show experimentally that RVRRTs can solve constrained problems with as many as 64 degrees of freedom and unconstrained problems with as many as 134 degrees of freedom. RVRRTs can solve problems more efficiently than existing methods, requiring fewer nodes and collision detection calls. We also show that it is capable of solving difficult problems that existing methods cannot.

  6. Reachable volume RRT

    KAUST Repository

    McMahon, Troy; Thomas, Shawna; Amato, Nancy M.

    2015-01-01

    © 2015 IEEE. Reachable volumes are a new technique that allows one to efficiently restrict sampling to feasible/reachable regions of the planning space even for high degree of freedom and highly constrained problems. However, they have so far only been applied to graph-based sampling-based planners. In this paper we develop the methodology to apply reachable volumes to tree-based planners such as Rapidly-Exploring Random Trees (RRTs). In particular, we propose a reachable volume RRT called RVRRT that can solve high degree of freedom problems and problems with constraints. To do so, we develop a reachable volume stepping function, a reachable volume expand function, and a distance metric based on these operations. We also present a reachable volume local planner to ensure that local paths satisfy constraints for methods such as PRMs. We show experimentally that RVRRTs can solve constrained problems with as many as 64 degrees of freedom and unconstrained problems with as many as 134 degrees of freedom. RVRRTs can solve problems more efficiently than existing methods, requiring fewer nodes and collision detection calls. We also show that it is capable of solving difficult problems that existing methods cannot.

  7. Validating the Electric Maze Task as a Measure of Planning

    Science.gov (United States)

    Sheppard, Kelly W.; Cheatham, Carol L.

    2017-01-01

    The Electric Maze Task (EMT) is a novel planning task designed to allow flexible testing of planning abilities across a broad age range and to incorporate manipulations to test underlying planning abilities, such as working-memory and inhibitory control skills. The EMT was tested in a group of 63 typically developing 7- to 12-year-olds.…

  8. Change in volume of lumpectomy cavity during external-beam irradiation of the intact breast

    International Nuclear Information System (INIS)

    Jacobson, Geraldine; Betts, Vicki; Smith, Brian

    2006-01-01

    Purpose: Definition of the lumpectomy cavity is an important component of irradiation of the breast. We use computed tomography (CT)-based planning and contour the lumpectomy volume on the planning CT. We obtained a second CT in the 4th or 5th week of treatment for boost planning and compared the volume change with the first planning-CT scan. Methods and Materials: This retrospective study reviewed the planning-CT data for 20 patients. In the first CT, images were obtained from the mandible to 2 cm below the breast in 3-mm slices. In the second CT, for the boost, images were obtained from the top to the bottom of the clinically defined breast, in 3-mm slices. Lumpectomy cavities were contoured on both CT scans and volumes compared. Results: Sixteen of the 20 patients (80%) had more than a 20% decrease from the first to the second volume, with a corresponding 95% confidence interval. The mean decrease was 16.13 cc, with a standard deviation of 14.05. The Spearman correlation coefficient of 0.18 did not show a significant correlation between the initial volume and the percent change. Conclusions: During external breast irradiation, many patients will have significant volume reduction in the lumpectomy cavity. Because CT-based definition of the lumpectomy cavity can influence the planning of a boost technique, further study appears warranted

  9. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126

    International Nuclear Information System (INIS)

    Moore, Kevin L.; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A.; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J.; Dicker, Adam P.; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-01-01

    Purpose: The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. Methods and Materials: A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH 0126,top10% ). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed “high-quality,” “low-quality,” and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Results: Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH 0126,top10% to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP

  10. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126.

    Science.gov (United States)

    Moore, Kevin L; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J; Dicker, Adam P; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-06-01

    The purpose of this study was to quantify the frequency and clinical severity of quality deficiencies in intensity modulated radiation therapy (IMRT) planning in the Radiation Therapy Oncology Group 0126 protocol. A total of 219 IMRT patients from the high-dose arm (79.2 Gy) of RTOG 0126 were analyzed. To quantify plan quality, we used established knowledge-based methods for patient-specific dose-volume histogram (DVH) prediction of organs at risk and a Lyman-Kutcher-Burman (LKB) model for grade ≥2 rectal complications to convert DVHs into normal tissue complication probabilities (NTCPs). The LKB model was validated by fitting dose-response parameters relative to observed toxicities. The 90th percentile (22 of 219) of plans with the lowest excess risk (difference between clinical and model-predicted NTCP) were used to create a model for the presumed best practices in the protocol (pDVH0126,top10%). Applying the resultant model to the entire sample enabled comparisons between DVHs that patients could have received to DVHs they actually received. Excess risk quantified the clinical impact of suboptimal planning. Accuracy of pDVH predictions was validated by replanning 30 of 219 patients (13.7%), including equal numbers of presumed "high-quality," "low-quality," and randomly sampled plans. NTCP-predicted toxicities were compared to adverse events on protocol. Existing models showed that bladder-sparing variations were less prevalent than rectum quality variations and that increased rectal sparing was not correlated with target metrics (dose received by 98% and 2% of the PTV, respectively). Observed toxicities were consistent with current LKB parameters. Converting DVH and pDVH0126,top10% to rectal NTCPs, we observed 94 of 219 patients (42.9%) with ≥5% excess risk, 20 of 219 patients (9.1%) with ≥10% excess risk, and 2 of 219 patients (0.9%) with ≥15% excess risk. Replanning demonstrated the predicted NTCP reductions while maintaining the volume of the PTV

  11. External Validation and Optimization of International Consensus Clinical Target Volumes for Adjuvant Radiation Therapy in Bladder Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Abhinav V. [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Christodouleas, John P. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Wu, Tianming [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Smith, Norman D.; Steinberg, Gary D. [Section of Urology, Department of Surgery, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Liauw, Stanley L., E-mail: sliauw@radonc.uchicago.edu [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States)

    2017-03-15

    Purpose: International consensus (IC) clinical target volumes (CTVs) have been proposed to standardize radiation field design in the treatment of patients at high risk of locoregional failure (LRF) after radical cystectomy. The purpose of this study was to externally validate the IC CTVs in a cohort of postsurgical patients followed up for LRF and identify revisions that might improve the IC CTVs' performance. Methods and Materials: Among 334 patients with pT3 to pT4 bladder cancer treated with radical cystectomy, LRF developed in 58 (17%), of whom 52 had computed tomography scans available for review. Images with LRF were exported into a treatment planning system, and IC CTVs were contoured and evaluated for adequacy of coverage of each LRF with respect to both the patient and each of 6 pelvic subsites: common iliac (CI) region, obturator region (OR), external and internal iliac region, presacral region, cystectomy bed, or other pelvic site. Revisions to the IC contours were proposed based on the findings. Results: Of the 52 patients with documented LRF, 13 (25%) had LRFs that were outside of the IC CTV involving 17 pelvic subsites: 5 near the CI CTV, 5 near the OR CTV, 1 near the external and internal iliac region, and 6 near the cystectomy bed. The 5 CI failures were located superior to the CTV, and the 5 OR failures were located medial to the CTV. Increasing the superior boundary of the CI to a vessel-based definition of the aortic bifurcation, as well as increasing the medial extension of the OR by an additional 9 mm, decreased the number of patients with LRF outside of the IC CTV to 7 (13%). Conclusions: Modified IC CTVs inclusive of a slight adjustment superiorly for the CI region and medially for the OR may reduce the risk of pelvic failure in patients treated with adjuvant radiation therapy.

  12. Endoscopic clipping for gastrointestinal tumors. A method to define the target volume more precisely

    International Nuclear Information System (INIS)

    Riepl, M.; Klautke, G.; Fehr, R.; Fietkau, R.; Pietsch, A.

    2000-01-01

    Background: In many cases it is not possible to exactly define the extension of carcinoma of the gastrointestinal tract with the help of computertomography scans made for 3-D-radiation treatment planning. Consequently, the planning of external beam radiotherapy is made more difficult for the gross tumor volume as well as, in some cases, also for the clinical target volume. Patients and Methods: Eleven patients with macrosocpic tumors (rectal cancer n = 5, cardiac cancer n = 6) were included. Just before 3-D planning, the oral and aboral border of the tumor was marked endoscopically with hemoclips. Subsequently, CT scans for radiotherapy planning were made and the clinical target volume was defined. Five to 6 weeks thereafter, new CT scans were done to define the gross tumor volume for boost planning. Two investigators independently assessed the influence of the hemoclips on the different planning volumes, and whether the number of clips was sufficient to define the gross tumor volume. Results: In all patients, the implantation of the clips was done without complications. Start of radiotherapy was not delayed. With the help of the clips it was possible to exactly define the position and the extension of the primary tumor. The clinical target volume was modified according to the position of the clips in 5/11 patients; the gross tumor volume was modified in 7/11 patients. The use of the clips made the documentation and verification of the treatment portals by the simulator easier. Moreover, the clips helped the surgeon to define the primary tumor region following marked regression after neoadjuvant therapy in 3 patients. Conclusions: Endoscopic clipping of gastrointestinal tumors helps to define the tumor volumes more precisely in radiation therapy. The clips are easily recognized on the portal films and, thus, contribute to quality control. (orig.) [de

  13. Commissioning and Validation of the First Monte Carlo Based Dose Calculation Algorithm Commercial Treatment Planning System in Mexico

    International Nuclear Information System (INIS)

    Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A.; Hernandez-Bojorquez, M.; Galvan de la Cruz, O. O.; Ballesteros-Zebadua, P.

    2010-01-01

    This work presents the beam data commissioning and dose calculation validation of the first Monte Carlo (MC) based treatment planning system (TPS) installed in Mexico. According to the manufacturer specifications, the beam data commissioning needed for this model includes: several in-air and water profiles, depth dose curves, head-scatter factors and output factors (6x6, 12x12, 18x18, 24x24, 42x42, 60x60, 80x80 and 100x100 mm 2 ). Radiographic and radiochromic films, diode and ionization chambers were used for data acquisition. MC dose calculations in a water phantom were used to validate the MC simulations using comparisons with measured data. Gamma index criteria 2%/2 mm were used to evaluate the accuracy of MC calculations. MC calculated data show an excellent agreement for field sizes from 18x18 to 100x100 mm 2 . Gamma analysis shows that in average, 95% and 100% of the data passes the gamma index criteria for these fields, respectively. For smaller fields (12x12 and 6x6 mm 2 ) only 92% of the data meet the criteria. Total scatter factors show a good agreement ( 2 ) that show a error of 4.7%. MC dose calculations are accurate and precise for clinical treatment planning up to a field size of 18x18 mm 2 . Special care must be taken for smaller fields.

  14. Validation of tomographic measurement of cerebral blood volume with C-11-labeled carboxyhemoglobin

    International Nuclear Information System (INIS)

    Phelps, M.E.; Huang, S.C.; Hoffman, E.J.; Kuhl, D.E.

    1979-01-01

    Red blood cells, tagged with C-11 administration of 11 CO gas, have been used to portray the distribution of blood in the brain. To date, however, the accuracy of this approach has not been validated. We have performed in vitro measurements of regional cerebral blood volume (CBV) with red blood cells labeled with C-11 and Cr-51 in four dogs and two rhesus monkeys. These studies yielded a ratio of CBV/sub C-1/ to CBV/sub Cr-11/ of 1.02 +- 0.03 (s.d.) from 92 samples. A least-squares fit to these data showed CBV/sub C-11/ = 1.01 CBV/sub Cr-51/ + 0.037; P much 11 CO-RBC gave coefficients of variation of +- 2.8% and +- 4.8% for cross-sectional CBV and regional (approx.4 cm 2 ) CBV over an 80-min period. The average human CBV was found to be 4.2 +- 0.4 cc blood per 100 g tissue. Clear tomographic delineation of the distribution of CBV in human subjects is achieved with ECT, which provides a ''live'' measurement of this parameter of cerebral hemodynamics. These data demonstrate that 11 CO administered by single-breath inhalation is a reliable and accurate blood tracer for measurement of CBV with ECT

  15. Turnaround Operations Analysis for OTV. Volume 3: Technology Development Plan

    Science.gov (United States)

    1988-01-01

    An integrated technology development plan for the technologies required to process both GBOTVs and SBOTVs are described. The plan includes definition of the tests and experiments to be accomplished on the ground, in a Space Shuttle Sortie Mission, on an Expendable Launch Vehicle, or at the Space Station as a Technology Development Mission (TDM). The plan reflects and accommodates current and projected research and technology programs where appropriate.

  16. Volume independence in large Nc QCD-like gauge theories

    International Nuclear Information System (INIS)

    Kovtun, Pavel; Uensal, Mithat; Yaffe, Laurence G.

    2007-01-01

    Volume independence in large N c gauge theories may be viewed as a generalized orbifold equivalence. The reduction to zero volume (or Eguchi-Kawai reduction) is a special case of this equivalence. So is temperature independence in confining phases. A natural generalization concerns volume independence in 'theory space' of quiver gauge theories. In pure Yang-Mills theory, the failure of volume independence for sufficiently small volumes (at weak coupling) due to spontaneous breaking of center symmetry, together with its validity above a critical size, nicely illustrate the symmetry realization conditions which are both necessary and sufficient for large N c orbifold equivalence. The existence of a minimal size below which volume independence fails also applies to Yang-Mills theory with antisymmetric representation fermions [QCD(AS)]. However, in Yang-Mills theory with adjoint representation fermions [QCD(Adj)], endowed with periodic boundary conditions, volume independence remains valid down to arbitrarily small size. In sufficiently large volumes, QCD(Adj) and QCD(AS) have a large N c ''orientifold'' equivalence, provided charge conjugation symmetry is unbroken in the latter theory. Therefore, via a combined orbifold-orientifold mapping, a well-defined large N c equivalence exists between QCD(AS) in large, or infinite, volume and QCD(Adj) in arbitrarily small volume. Since asymptotically free gauge theories, such as QCD(Adj), are much easier to study (analytically or numerically) in small volume, this equivalence should allow greater understanding of large N c QCD in infinite volume

  17. Validation of a Theory of Planned Behavior-Based Questionnaire to Examine Factors Associated With Milk Expression.

    Science.gov (United States)

    Bai, Yeon K; Dinour, Lauren M

    2017-11-01

    A proper assessment of multidimensional needs for breastfeeding mothers in various settings is crucial to facilitate and support breastfeeding and its exclusivity. The theory of planned behavior (TPB) has been used frequently to measure factors associated with breastfeeding. Full utility of the TPB requires accurate measurement of theory constructs. Research aim: This study aimed to develop and confirm the psychometric properties of an instrument, Milk Expression on Campus, based on the TPB and to establish the reliability and validity of the instrument. In spring 2015, 218 breastfeeding (current or in the recent past) employees and students at one university campus in northern New Jersey completed the online questionnaire containing demography and theory-based items. Internal consistency (α) and split-half reliability ( r) tests and factor analyses established and confirmed the reliability and construct validity of this instrument. Milk Expression on Campus showed strong and significant reliabilities as a full scale (α = .78, r = .74, p theory construct subscales. Validity was confirmed as psychometric properties corresponded to the factors extracted from the scale. Four factors extracted from the direct construct subscales accounted for 79.49% of the total variability. Four distinct factors from the indirect construct subscales accounted for 73.68% of the total variability. Milk Expression on Campus can serve as a model TPB-based instrument to examine factors associated with women's milk expression behavior. The utility of this instrument extends to designing effective promotion programs to foster breastfeeding and milk expression behaviors in diverse settings.

  18. ICRU reference dose in an era of intensity-modulated radiation therapy clinical trials: Correlation with planning target volume mean dose and suitability for intensity-modulated radiation therapy dose prescription

    International Nuclear Information System (INIS)

    Yaparpalvi, Ravindra; Hong, Linda; Mah, Dennis; Shen Jin; Mutyala, Subhakar; Spierer, Marnee; Garg, Madhur; Guha, Chandan; Kalnicki, Shalom

    2008-01-01

    Background and Purpose: IMRT clinical trials lack dose prescription and specification standards similar to ICRU standards for two- and three-dimensional external beam planning. In this study, we analyzed dose distributions for patients whose treatment plans incorporated IMRT, and compared the dose determined at the ICRU reference point to the PTV doses determined from dose-volume histograms. Additionally, we evaluated if ICRU reference type single-point dose prescriptions are suitable for IMRT dose prescriptions. Materials and methods: For this study, IMRT plans of 117 patients treated at our institution were randomly selected and analyzed. The treatment plans were clinically applied to the following disease sites: abdominal (11), anal (10), brain (11), gynecological (15), head and neck (25), lung (15), male pelvis (10) and prostate (20). The ICRU reference point was located in each treatment plan following ICRU Report 50 guidelines. The reference point was placed in the central part of the PTV and at or near the isocenter. In each case, the dose was calculated and recorded to this point. For each patient - volume and dose (PTV, PTV mean, median and modal) information was extracted from the planned dose-volume histogram. Results: The ICRU reference dose vs PTV mean dose relationship in IMRT exhibited a weak positive association (Pearson correlation coefficient 0.63). In approximately 65% of the cases studied, dose at the ICRU reference point was greater than the corresponding PTV mean dose. The dose difference between ICRU reference and PTV mean doses was ≤2% in approximately 79% of the cases studied (average 1.21% (±1.55), range -4% to +4%). Paired t-test analyses showed that the ICRU reference doses and PTV median doses were statistically similar (p = 0.42). The magnitude of PTV did not influence the difference between ICRU reference and PTV mean doses. Conclusions: The general relationship between ICRU reference and PTV mean doses in IMRT is similar to that

  19. A comparison of different three-dimensional treatment planning techniques for localized radiotherapy of prostate cancer

    International Nuclear Information System (INIS)

    Koswig, S.; Dinges, S.; Buchali, A.; Boehmer, D.; Salk, J.; Rosenthal, P.; Harder, C.; Schlenger, L.; Budach, V.

    1999-01-01

    Purpose: Four different three-dimensional planning techniques for localized radiotherapy of prostate cancer were compared with regard to dose homogeneity within the target volume and dose to organs at risk, dependent upon tumor stage. Patients and Methods: Six patients with stage T1, 7 patients with stage T2 and 4 patients with stage T3 were included in this study. Four different 3D treatment plans (rotation, 4-field, 5-field and 6-field technique) were calculated for each patient. Dose was calculated with the reference point at the isocenter (100%). The planning target volume was encompassed within the 95% isodose surface. All the techniques used different shaped portal for each beam. Dose volume histograms were created and compared for the planning target volume and the organs at risk (33%, 50%, 66% volume level) in all techniques. Results: The 4 different three-dimensional planning techniques revealed no differences concerning dose homogeneity within the planning target volume. The dose volume distribution at organs at risk show differences between the calculated techniques. In our study the best protection for bladder and rectum in stage T1 and T2 was achieved by the 6-field technique. A significant difference was achieved between 6-field and 4-field technique only in the 50% volume of the bladder (p=0.034), between the 6-field and rotation technique (all volume levels) and between 5-field and rotation technique (all volume levels). In stage T1, T2 6-field and 4-field technique in 50% (p-0.033) and 66% (p=0.011) of the rectum volume. In stage T3 a significant difference was not observed between the 4 techniques. The best protection of head of the femur was achieved by the rotation technique. Conclusion: In the localized radiotherapy of prostate cancer in stage T1 or T2 the best protection for bladder and rectum was achieved by a 3D-planned conformal 6-field technique. If the seminal vesicles have been included in the target volume and in the case of large

  20. Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

    International Nuclear Information System (INIS)

    Thompson, S.A.; Fung, A.Y.C.; Zaider, M.

    2002-01-01

    One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results. (author)

  1. Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, S.A. [Department of Medical Physics, North Shore-Long Island Jewish Health System, Manhassett, NY (United States); Fung, A.Y.C.; Zaider, M. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2002-08-21

    One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results. (author)

  2. The Validation of the Mixedwood Growth Model (MGM for Use in Forest Management Decision Making

    Directory of Open Access Journals (Sweden)

    Mike Bokalo

    2013-01-01

    Full Text Available We evaluated the Mixedwood Growth Model (MGM at a whole model scale for pure and mixed species stands of aspen and white spruce in the western boreal forest. MGM is an individual tree-based, distance-independent growth model, designed to evaluate growth and yield implications relating to the management of white spruce, black spruce, aspen, lodgepole pine, and mixedwood stands in Alberta, British Columbia, Saskatchewan, and Manitoba. Our validation compared stand-level model predictions against re-measured data (volume, basal area, diameter at breast height (DBH, average and top height and density from permanent sample plots using combined analysis of residual plots, bias statistics, efficiency and an innovative application of the equivalence test. For state variables, the model effectively simulated juvenile and mature stages of stand development for both pure and mixed species stands of aspen and white spruce in Alberta. MGM overestimates increment in older stands likely due to age-related pathology and weather-related stand damage. We identified underestimates of deciduous density and volume in Saskatchewan. MGM performs well for increment in postharvest stands less than 30 years of age. These results illustrate the comprehensive application of validation metrics to evaluate a complex model, and provide support for the use of MGM in management planning.

  3. Analysis of nodal coverage utilizing image guided radiation therapy for primary gynecologic tumor volumes

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Faisal [University of Utah School of Medicine, Salt Lake City, UT (United States); Loma Linda University Medical Center, Department of Radiation Oncology, Loma Linda, CA (United States); Sarkar, Vikren; Gaffney, David K.; Salter, Bill [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States); Poppe, Matthew M., E-mail: matthew.poppe@hci.utah.edu [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States)

    2016-10-01

    Purpose: To evaluate radiation dose delivered to pelvic lymph nodes, if daily Image Guided Radiation Therapy (IGRT) was implemented with treatment shifts based on the primary site (primary clinical target volume [CTV]). Our secondary goal was to compare dosimetric coverage with patient outcomes. Materials and methods: A total of 10 female patients with gynecologic malignancies were evaluated retrospectively after completion of definitive intensity-modulated radiation therapy (IMRT) to their pelvic lymph nodes and primary tumor site. IGRT consisted of daily kilovoltage computed tomography (CT)-on-rails imaging fused with initial planning scans for position verification. The initial plan was created using Varian's Eclipse treatment planning software. Patients were treated with a median radiation dose of 45 Gy (range: 37.5 to 50 Gy) to the primary volume and 45 Gy (range: 45 to 64.8 Gy) to nodal structures. One IGRT scan per week was randomly selected from each patient's treatment course and re-planned on the Eclipse treatment planning station. CTVs were recreated by fusion on the IGRT image series, and the patient's treatment plan was applied to the new image set to calculate delivered dose. We evaluated the minimum, maximum, and 95% dose coverage for primary and nodal structures. Reconstructed primary tumor volumes were recreated within 4.7% of initial planning volume (0.9% to 8.6%), and reconstructed nodal volumes were recreated to within 2.9% of initial planning volume (0.01% to 5.5%). Results: Dosimetric parameters averaged less than 10% (range: 1% to 9%) of the original planned dose (45 Gy) for primary and nodal volumes on all patients (n = 10). For all patients, ≥99.3% of the primary tumor volume received ≥ 95% the prescribed dose (V95%) and the average minimum dose was 96.1% of the prescribed dose. In evaluating nodal CTV coverage, ≥ 99.8% of the volume received ≥ 95% the prescribed dose and the average minimum dose was 93%. In

  4. How precise is manual CT-MRI registration for cranial radiotherapy planning?

    International Nuclear Information System (INIS)

    Mosleh-Shirazi, M. A.; South, P. C.

    2005-01-01

    Manual fusion is a readily available image registration technique that does not require matching algorithms. The operator performs rigid-body transformations interactively. The precision of Manual fusion (as implemented on the Philips Pinnacle treatment planning system) was required for cranial CT-MR images used in radiotherapy planning for typical centrally located planning target volumes . Materials and Methods: A multi-stage Manual fusion procedure was developed which 11 observers followed to match the head contour, bones, soft tissues and contoured structures for 5 patient image-sets. Registration parameters were calculated by solving the transformation matrix following a consistent order of translations (T) and rotations (R). The mean position of centre of each planning target volumes averaged over all observers was used as the reference. The effect of mis registration on the planning target volumes co-ordinates and the volume increase resulting from application of a margin for registration uncertainty were calculated. Results: Mean intra- and inter-observer T/R SDs were 0.5 mm/ 0.4 d ig a nd 1.1 mm/ 1.0 d ig , respectively. Mean intra- and inter-observer registration error (3D distance of each planning target volumes centre from the mean position for all observers) was 0.7 ±0.3 mm (1 SD) and 1.6±0.7 mm respectively, the latter reducing to 1.4±0.6 mm excluding the 3 least experienced operators. A subsequent 2 mm margin for mis registration on average increased the planning target volume by 27%. Conclusion: Moderately trained operators produced clinically acceptable results while experienced operators improved the precision. Manual fusion still has an important role in the registration of cranial CT and MR images for radiotherapy planning especially for under-resourced centers

  5. Development, Verification and Validation of Parallel, Scalable Volume of Fluid CFD Program for Propulsion Applications

    Science.gov (United States)

    West, Jeff; Yang, H. Q.

    2014-01-01

    There are many instances involving liquid/gas interfaces and their dynamics in the design of liquid engine powered rockets such as the Space Launch System (SLS). Some examples of these applications are: Propellant tank draining and slosh, subcritical condition injector analysis for gas generators, preburners and thrust chambers, water deluge mitigation for launch induced environments and even solid rocket motor liquid slag dynamics. Commercially available CFD programs simulating gas/liquid interfaces using the Volume of Fluid approach are currently limited in their parallel scalability. In 2010 for instance, an internal NASA/MSFC review of three commercial tools revealed that parallel scalability was seriously compromised at 8 cpus and no additional speedup was possible after 32 cpus. Other non-interface CFD applications at the time were demonstrating useful parallel scalability up to 4,096 processors or more. Based on this review, NASA/MSFC initiated an effort to implement a Volume of Fluid implementation within the unstructured mesh, pressure-based algorithm CFD program, Loci-STREAM. After verification was achieved by comparing results to the commercial CFD program CFD-Ace+, and validation by direct comparison with data, Loci-STREAM-VoF is now the production CFD tool for propellant slosh force and slosh damping rate simulations at NASA/MSFC. On these applications, good parallel scalability has been demonstrated for problems sizes of tens of millions of cells and thousands of cpu cores. Ongoing efforts are focused on the application of Loci-STREAM-VoF to predict the transient flow patterns of water on the SLS Mobile Launch Platform in order to support the phasing of water for launch environment mitigation so that vehicle determinantal effects are not realized.

  6. Estimation of soil erosion for a sustainable land use planning: RUSLE model validation by remote sensing data utilization in the Kalikonto watershed

    Directory of Open Access Journals (Sweden)

    C. Andriyanto

    2015-10-01

    Full Text Available Technology of Geographic Information Systems (GIS and Remote Sensing (RS are increasingly used for planning and natural resources management. GIS and RS is based on pixels is used as a tool of spatial modeling for predicting the erosion. One of the methods developed for predicting the erosion is a Revised Universal Soil Loss Equation (RUSLE. RUSLE is the method used for predicting the erosion associated with runoff gained from five parameters, namely: rain erosivity (R, soil erodibility (K, length of slopes (L, slope (S, and land management (CP. The main constraint encountered in the process of operating the GIS is the calculation of the slope length factor (L.This study was designed to create a plan of sustainable land use and low erosion through the RULSE erosion modeling by utilizing the remote sensing data. With this approach, this study was divided into three activities, namely (1 the preparation and analysis of spatial data for the determination of the parameters and estimating the erosion by using RUSLE models, (2 the validation and calibration of the model of RUSLE by measuring soil erosion at the scale of plots on the field, and (3 Creating a plan of sustainable land use and low erosion with RUSLE. The validation erosion shows the value of R2 = 0.56 and r = 0.74. Results of this study showed that the RUSLE model could be used in the Kalikonto watershed. The erosions at the value of the actual estimation, spatial Plan (RTRW and land capability class in the Kalikonto watershed were 72t / ha / year, 62 t / ha / year and 58 t / ha / year, respectively.

  7. Relaxation volumes of self-interstitial-atoms and vacancies in metals

    International Nuclear Information System (INIS)

    Ehrhart, P.

    1983-01-01

    Experimental results for the relaxation volumes of self-interstitial-atoms and vacancies as obtained after low temperature irradiation of different metals are reviewed. For fcc metals the relaxation volumes of the SIA's are very similar: ΔVsup(rel) = 1.6 +- 0.3 atomic volumes. This value is valid as well for the pure fcc metals (Al, Cu, Ni) as for different alloys. Vacancy relaxation volumes are small and vary between: ΔVsup(rel) = -0.05 and -0.25 atomic volumes. For bcc metals (Fe, Mo) the relaxation volume of the SIA is significantly smaller: ΔVsup(rel) = 1.1 +- 0.2 atomic volumes. In spite of the obvious similarity of the close-packed fcc and hcp structures, the SIA parameters for hcp metals are much different: ΔVsup(rel) = 3.5 for Zn, ΔVsup(rel) = 1.5 for Co and ΔVsup(rel) = 0.6 at. vol. for Zr. Vacancy relaxation volumes seem to be small as in cubic metals. The influence of lattice nonharmonicity on the validity of an extrapolation of the values determined at 6 K to higher temperatures is discussed. (author)

  8. Guidelines for the verification and validation of expert system software and conventional software: Survey and documentation of expert system verification and validation methodologies. Volume 3

    International Nuclear Information System (INIS)

    Groundwater, E.H.; Miller, L.A.; Mirsky, S.M.

    1995-03-01

    This report is the third volume in the final report for the Expert System Verification and Validation (V ampersand V) project which was jointly sponsored by the Nuclear Regulatory Commission and the Electric Power Research Institute. The ultimate objective is the formulation of guidelines for the V ampersand V of expert systems for use in nuclear power applications. The purpose of this activity was to survey and document techniques presently in use for expert system V ampersand V. The survey effort included an extensive telephone interviewing program, site visits, and a thorough bibliographic search and compilation. The major finding was that V ampersand V of expert systems is not nearly as established or prevalent as V ampersand V of conventional software systems. When V ampersand V was used for expert systems, it was almost always at the system validation stage after full implementation and integration usually employing the non-systematic dynamic method of open-quotes ad hoc testing.close quotes There were few examples of employing V ampersand V in the early phases of development and only weak sporadic mention of the possibilities in the literature. There is, however, a very active research area concerning the development of methods and tools to detect problems with, particularly, rule-based expert systems. Four such static-testing methods were identified which were not discovered in a comprehensive review of conventional V ampersand V methods in an earlier task

  9. Validation of a computational method for assessing the impact of intra-fraction motion on helical tomotherapy plans

    Energy Technology Data Exchange (ETDEWEB)

    Ngwa, Wilfred; Meeks, Sanford L; Kupelian, Patrick A; Langen, Katja M [Department of Radiation Oncology, M D Anderson Cancer Center Orlando, 1400 South Orange Avenue, Orlando, FL 32806 (United States); Schnarr, Eric [TomoTherapy, Inc., 1240 Deming Way, Madison, WI 53717 (United States)], E-mail: wilfred.ngwa@orlandohealth.com

    2009-11-07

    In this work, a method for direct incorporation of patient motion into tomotherapy dose calculations is developed and validated. This computational method accounts for all treatment dynamics and can incorporate random as well as cyclical motion data. Hence, interplay effects between treatment dynamics and patient motion are taken into account during dose calculation. This allows for a realistic assessment of intra-fraction motion on the dose distribution. The specific approach entails modifying the position and velocity events in the tomotherapy delivery plan to accommodate any known motion. The computational method is verified through phantom and film measurements. Here, measured prostate motion and simulated respiratory motion tracks were incorporated in the dose calculation. The calculated motion-encoded dose profiles showed excellent agreement with the measurements. Gamma analysis using 3 mm and 3% tolerance criteria showed over 97% and 96% average of points passing for the prostate and breathing motion tracks, respectively. The profile and gamma analysis results validate the accuracy of this method for incorporating intra-fraction motion into the dose calculation engine for assessment of dosimetric effects on helical tomotherapy dose deliveries.

  10. 3-D conformal radiation therapy - Part I: Treatment planning

    International Nuclear Information System (INIS)

    Burman, Chandra M.; Mageras, Gikas S.

    1997-01-01

    Objective: In this presentation we will look into the basic components of 3-dimensional conformal treatment planning, and will discuss planning for some selected sites. We will also review some current and future trends in 3-D treatment planning. External beam radiation therapy is one of the arms of cancer treatment. In the recent years 3-D conformal therapy had significant impact on the practice of external beam radiation therapy. Conformal radiation therapy shapes the high-dose volume so as to conform to the target volume while minimizing the dose to the surrounding normal tissues. The advances that have been achieved in conformal therapy are in part due to the development of 3-D treatment planning, which in turn has capitalized on 3-D imaging for tumor and normal tissue localization, as well as on available computational power for the calculation of 3-D dose distributions, visualization of anatomical and dose volumes, and numerical evaluation of treatment plans. In this course we will give an overview of how 3-D conformal treatments are designed and transferred to the patient. Topics will include: 1) description of the major components of a 3-D treatment planning system, 2) techniques for designing treatments, 3) evaluation of treatment plans using dose distribution displays, dose-volume histograms and normal tissue complication probabilities, 4) implementation of treatments using shaped blocks and multileaf collimators, 5) verification of treatment delivery using portal films and electronic portal imaging devices. We will also discuss some current and future trends in 3-D treatment planning, such as field shaping with multileaf collimation, computerized treatment plan optimization, including the use of nonuniform beam profiles (intensity modulation), and incorporating treatment uncertainties due to patient positioning errors and organ motion into treatment planning process

  11. Long-range research plan. FY 1987-FY 1991. Volume 3

    International Nuclear Information System (INIS)

    1986-08-01

    The Long-Range Research Plan (LRRP) was prepared by the Office of Nuclear Regulatory Research (RES) to assist the NRC in coordinating its long-range research planning with the short-range budget cycles. The LRRP lays out programmatic approaches for research to help resolve regulatory issues. The plan will be updated annually. It covers: operating reactor inspection, maintenance, and repair; equipment qualification; seismic research; reactor operations and risk; thermal-hydraulic transients; severe accidents; radiation protection and health effects; and waste management

  12. Long-Range Research Plan, FY 1986-FY 1990. Volume 2

    International Nuclear Information System (INIS)

    1985-08-01

    The Long-Range Research Plan (LRRP) was prepared by the Office of Nuclear Regulatory Research (RES) to assist the NRC in coordinating its long-range research planning with the short-range budget cycles. The LRRP lays out programmatic approaches for research to help resolve regulatory issues. The plan will be updated annually. It covers: operating reactor inspection, maintenance, and repair; equipment qualification; seismic research; reactor operations and risk; thermal-hydraulic transients; severe accidents; radiation protection and health effects; and waste management

  13. An Ensemble Approach to Knowledge-Based Intensity-Modulated Radiation Therapy Planning

    Directory of Open Access Journals (Sweden)

    Jiahan Zhang

    2018-03-01

    Full Text Available Knowledge-based planning (KBP utilizes experienced planners’ knowledge embedded in prior plans to estimate optimal achievable dose volume histogram (DVH of new cases. In the regression-based KBP framework, previously planned patients’ anatomical features and DVHs are extracted, and prior knowledge is summarized as the regression coefficients that transform features to organ-at-risk DVH predictions. In our study, we find that in different settings, different regression methods work better. To improve the robustness of KBP models, we propose an ensemble method that combines the strengths of various linear regression models, including stepwise, lasso, elastic net, and ridge regression. In the ensemble approach, we first obtain individual model prediction metadata using in-training-set leave-one-out cross validation. A constrained optimization is subsequently performed to decide individual model weights. The metadata is also used to filter out impactful training set outliers. We evaluate our method on a fresh set of retrospectively retrieved anonymized prostate intensity-modulated radiation therapy (IMRT cases and head and neck IMRT cases. The proposed approach is more robust against small training set size, wrongly labeled cases, and dosimetric inferior plans, compared with other individual models. In summary, we believe the improved robustness makes the proposed method more suitable for clinical settings than individual models.

  14. Artificial Neural Network-Based System for PET Volume Segmentation

    Directory of Open Access Journals (Sweden)

    Mhd Saeed Sharif

    2010-01-01

    Full Text Available Tumour detection, classification, and quantification in positron emission tomography (PET imaging at early stage of disease are important issues for clinical diagnosis, assessment of response to treatment, and radiotherapy planning. Many techniques have been proposed for segmenting medical imaging data; however, some of the approaches have poor performance, large inaccuracy, and require substantial computation time for analysing large medical volumes. Artificial intelligence (AI approaches can provide improved accuracy and save decent amount of time. Artificial neural networks (ANNs, as one of the best AI techniques, have the capability to classify and quantify precisely lesions and model the clinical evaluation for a specific problem. This paper presents a novel application of ANNs in the wavelet domain for PET volume segmentation. ANN performance evaluation using different training algorithms in both spatial and wavelet domains with a different number of neurons in the hidden layer is also presented. The best number of neurons in the hidden layer is determined according to the experimental results, which is also stated Levenberg-Marquardt backpropagation training algorithm as the best training approach for the proposed application. The proposed intelligent system results are compared with those obtained using conventional techniques including thresholding and clustering based approaches. Experimental and Monte Carlo simulated PET phantom data sets and clinical PET volumes of nonsmall cell lung cancer patients were utilised to validate the proposed algorithm which has demonstrated promising results.

  15. Annual plan, December 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This annual plan is being provided as required under Section 'D' of the Alberta Energy and Utilities Board Information Letter IL 90-8. The objective is to provide the Board, NOVA Gas Transmission (NGTL) customers and other interested parties with a comprehensive overview of NOVA Gas Transmission's pipeline system expansion plans for the gas year 2000/ 2001, and the winter season of the 2001/2002 gas year. The plan includes descriptions of NGTL's design assumptions and criteria, as well as long term outlook for field deliverability, productive capability, gas deliveries, proposed facility additions, capital expenditures, revenue requirements and firm service demand rates. Major factors affecting the facility requirements for the period under consideration are a decrease in the maximum day delivery volume at the Empress border point, an increase in intra-Alberta maximum day delivery volumes and associated decline in productive capability. Chapter One of the Plan describes the the Annual Plan process itself; Chapter Two is devoted to a discussion of facilities design methodology; Chapter Three deals with economic assumptions; Chapter Four describes design flow, while Chapters Five and Six outline the mainline , meter stations, laterals, and lateral loops facility requirements. Chapter Seven provides and overview of the capital and financial forecasts. tabs., figs.

  16. Strategies for automatic online treatment plan reoptimization using clinical treatment planning system: A planning parameters study

    International Nuclear Information System (INIS)

    Li, Taoran; Wu, Qiuwen; Zhang, You; Vergalasova, Irina; Lee, W. Robert; Yin, Fang-Fang; Wu, Q. Jackie

    2013-01-01

    Purpose: Adaptive radiation therapy for prostate cancer using online reoptimization provides an improved control of interfractional anatomy variations. However, the clinical implementation of online reoptimization is currently limited by the low efficiency of current strategies and the difficulties associated with integration into the current treatment planning system. This study investigates the strategies for performing fast (∼2 min) automatic online reoptimization with a clinical fluence-map-based treatment planning system; and explores the performance with different input parameters settings: dose-volume histogram (DVH) objective settings, starting stage, and iteration number (in the context of real time planning).Methods: Simulated treatments of 10 patients were reoptimized daily for the first week of treatment (5 fractions) using 12 different combinations of optimization strategies. Options for objective settings included guideline-based RTOG objectives, patient-specific objectives based on anatomy on the planning CT, and daily-CBCT anatomy-based objectives adapted from planning CT objectives. Options for starting stages involved starting reoptimization with and without the original plan's fluence map. Options for iteration numbers were 50 and 100. The adapted plans were then analyzed by statistical modeling, and compared both in terms of dosimetry and delivery efficiency.Results: All online reoptimized plans were finished within ∼2 min with excellent coverage and conformity to the daily target. The three input parameters, i.e., DVH objectives, starting stage, and iteration number, contributed to the outcome of optimization nearly independently. Patient-specific objectives generally provided better OAR sparing compared to guideline-based objectives. The benefit in high-dose sparing from incorporating daily anatomy into objective settings was positively correlated with the relative change in OAR volumes from planning CT to daily CBCT. The use of the

  17. Volumetric-modulated arc therapy in postprostatectomy radiotherapy patients: A planning comparison study

    International Nuclear Information System (INIS)

    Forde, Elizabeth; Kneebone, Andrew; Bromley, Regina; Guo, Linxin; Hunt, Peter; Eade, Thomas

    2013-01-01

    The purpose of this study was to compare postprostatectomy planning for volumetric-modulated arc therapy (VMAT) with both single arc (SA) and double arcs (DA) against dynamic sliding window intensity-modulated radiotherapy (IMRT). Ten cases were planned with IMRT, SA VMAT, and DA VMAT. All cases were planned to achieve a minimum dose of 68 Gy to 95% of the planning target volume (PTV) and goals to limit rectal volume >40 Gy to 35% and >65 Gy to 17%, and bladder volumes >40 Gy to 50% and >65 Gy to 25%. Plans were averaged across the 10 patients and compared for mean dose, conformity, homogeneity, rectal and bladder doses, and monitor units. The mean dose to the clinical target volume and PTV was significantly higher (p<0.05) for SA compared with DA or IMRT. The homogeneity index was not significantly different: SA = 0.09; DA = 0.08; and IMRT = 0.07. The rectal V40 was lowest for the DA plan. The rectal V20 was significantly lower (p<0.05) for both the VMAT plans compared with IMRT. There were no significant differences for bladder V40 or rectal and bladder V65. The IMRT plans required 1400 MU compared with 745 for DA and 708 for SA. This study shows that for equivalent dose coverage, SA and DA VMAT plans result in higher mean doses to the clinical target volume and PTV. This greater dose heterogeneity is balanced by improved low-range rectal doses and halving of the monitor units

  18. Volumetric-modulated arc therapy in postprostatectomy radiotherapy patients: A planning comparison study

    Energy Technology Data Exchange (ETDEWEB)

    Forde, Elizabeth, E-mail: eforde@tcd.ie [Radiation Oncology Department, Northern Sydney Cancer Centre, St Leonards, New South Wales (Australia); Kneebone, Andrew [Radiation Oncology Department, Northern Sydney Cancer Centre, St Leonards, New South Wales (Australia); Northern Clinical School, University of Sydney, New South Wales (Australia); Bromley, Regina [Institute of Medical Physics, School of Physics, University of Sydney, New South Wales (Australia); Guo, Linxin; Hunt, Peter [Radiation Oncology Department, Northern Sydney Cancer Centre, St Leonards, New South Wales (Australia); Eade, Thomas [Radiation Oncology Department, Northern Sydney Cancer Centre, St Leonards, New South Wales (Australia); Northern Clinical School, University of Sydney, New South Wales (Australia)

    2013-10-01

    The purpose of this study was to compare postprostatectomy planning for volumetric-modulated arc therapy (VMAT) with both single arc (SA) and double arcs (DA) against dynamic sliding window intensity-modulated radiotherapy (IMRT). Ten cases were planned with IMRT, SA VMAT, and DA VMAT. All cases were planned to achieve a minimum dose of 68 Gy to 95% of the planning target volume (PTV) and goals to limit rectal volume >40 Gy to 35% and >65 Gy to 17%, and bladder volumes >40 Gy to 50% and >65 Gy to 25%. Plans were averaged across the 10 patients and compared for mean dose, conformity, homogeneity, rectal and bladder doses, and monitor units. The mean dose to the clinical target volume and PTV was significantly higher (p<0.05) for SA compared with DA or IMRT. The homogeneity index was not significantly different: SA = 0.09; DA = 0.08; and IMRT = 0.07. The rectal V40 was lowest for the DA plan. The rectal V20 was significantly lower (p<0.05) for both the VMAT plans compared with IMRT. There were no significant differences for bladder V40 or rectal and bladder V65. The IMRT plans required 1400 MU compared with 745 for DA and 708 for SA. This study shows that for equivalent dose coverage, SA and DA VMAT plans result in higher mean doses to the clinical target volume and PTV. This greater dose heterogeneity is balanced by improved low-range rectal doses and halving of the monitor units.

  19. Assessing Assessment Texts: Where Is Planning?

    Science.gov (United States)

    Fives, Helenrose; Barnes, Nicole; Dacey, Charity; Gillis, Anna

    2016-01-01

    We conducted a content analysis of 27 assessment textbooks to determine how assessment planning was framed in texts for preservice teachers. We identified eight assessment planning themes: alignment, assessment purpose and types, reliability and validity, writing goals and objectives, planning specific assessments, unpacking, overall assessment…

  20. Evaluation of a commercial biologically based IMRT treatment planning system

    International Nuclear Information System (INIS)

    Semenenko, Vladimir A.; Reitz, Bodo; Day, Ellen; Qi, X. Sharon; Miften, Moyed; Li, X. Allen

    2008-01-01

    A new inverse treatment planning system (TPS) for external beam radiation therapy with high energy photons is commercially available that utilizes both dose-volume-based cost functions and a selection of cost functions which are based on biological models. The purpose of this work is to evaluate quality of intensity-modulated radiation therapy (IMRT) plans resulting from the use of biological cost functions in comparison to plans designed using a traditional TPS employing dose-volume-based optimization. Treatment planning was performed independently at two institutions. For six cancer patients, including head and neck (one case from each institution), prostate, brain, liver, and rectal cases, segmental multileaf collimator IMRT plans were designed using biological cost functions and compared with clinically used dose-based plans for the same patients. Dose-volume histograms and dosimetric indices, such as minimum, maximum, and mean dose, were extracted and compared between the two types of treatment plans. Comparisons of the generalized equivalent uniform dose (EUD), a previously proposed plan quality index (fEUD), target conformity and heterogeneity indices, and the number of segments and monitor units were also performed. The most prominent feature of the biologically based plans was better sparing of organs at risk (OARs). When all plans from both institutions were combined, the biologically based plans resulted in smaller EUD values for 26 out of 33 OARs by an average of 5.6 Gy (range 0.24 to 15 Gy). Owing to more efficient beam segmentation and leaf sequencing tools implemented in the biologically based TPS compared to the dose-based TPS, an estimated treatment delivery time was shorter in most (five out of six) cases with some plans showing up to 50% reduction. The biologically based plans were generally characterized by a smaller conformity index, but greater heterogeneity index compared to the dose-based plans. Overall, compared to plans based on dose-volume

  1. Can volumetric modulated arc therapy with flattening filter free beams play a role in stereotactic body radiotherapy for liver lesions? A volume-based analysis

    International Nuclear Information System (INIS)

    Reggiori, Giacomo; Mancosu, Pietro; Castiglioni, Simona; Alongi, Filippo; Pellegrini, Chiara; Lobefalo, Francesca; Catalano, Maddalena; Fogliata, Antonella; Arcangeli, Stefano; Navarria, Piera; Cozzi, Luca; Scorsetti, Marta

    2012-01-01

    Purpose: To compare volumetric modulated arc therapy with flattening filter free (FFF) and flattening filter (FF) beams in patients with hepatic metastases subject to hypofractionated radiotherapy (RT). Methods: A planning study on 13 virtual lesions of increasing volume was performed. Two single arc plans were optimized with the RapidArc technique using either FFF or FF beams. A second planning study was performed on ten patients treated for liver metastases to validate conclusions. In all cases, a dose of 75 Gy in 3 fractions was prescribed to the planning target volume (PTV) and plans were evaluated in terms of coverage, homogeneity, conformity, mean dose to healthy liver and to healthy tissue. For each parameter, results were expressed in relative terms as the percentage ratio between FFF and FF data. Results: In terms of PTV coverage, conformity index favored FFF for targets of intermediate size while FF resulted more suitable for small ( 3 ) and large (>300 cm 3 ) targets. Plans optimized with FFF beams resulted in increased sparing of healthy tissue in ≅85% of cases. Despite the qualitative results, no statistically significant differences were found between FFF and FF results. Plans optimized with un-flattened beams resulted in higher average MU/Gy than plans with FF beams. A remarkable and significant difference was observed in the beam-on time (BOT) needed to deliver plans. The BOT for FF plans was 8.2 ± 1.0 min; for FFF plans BOT was 2.2 ± 0.2 min. Conclusions: RapidArc plans optimized using FFF were dosimetrically equivalent to those optimized using FF beams, showing the feasibility of SBRT treatments with FFF beams. Some improvement in healthy tissue sparing was observed when using the FFF modality due to the different beam's profile. The main advantage was a considerable reduction of beam-on time, relevant for SBRT techniques.

  2. Improvement to Airport Throughput Using Intelligent Arrival Scheduling and an Expanded Planning Horizon

    Science.gov (United States)

    Glaab, Patricia C.

    2012-01-01

    The first phase of this study investigated the amount of time a flight can be delayed or expedited within the Terminal Airspace using only speed changes. The Arrival Capacity Calculator analysis tool was used to predict the time adjustment envelope for standard descent arrivals and then for CDA arrivals. Results ranged from 0.77 to 5.38 minutes. STAR routes were configured for the ACES simulation, and a validation of the ACC results was conducted comparing the maximum predicted time adjustments to those seen in ACES. The final phase investigated full runway-to-runway trajectories using ACES. The radial distance used by the arrival scheduler was incrementally increased from 50 to 150 nautical miles (nmi). The increased Planning Horizon radii allowed the arrival scheduler to arrange, path stretch, and speed-adjust flights to more fully load the arrival stream. The average throughput for the high volume portion of the day increased from 30 aircraft per runway for the 50 nmi radius to 40 aircraft per runway for the 150 nmi radius for a traffic set representative of high volume 2018. The recommended radius for the arrival scheduler s Planning Horizon was found to be 130 nmi, which allowed more than 95% loading of the arrival stream.

  3. WECC Variable Generation Planning Reference Book: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Makarov, Yuri V.; Du, Pengwei; Etingov, Pavel V.; Ma, Jian; Vyakaranam, Bharat

    2013-05-13

    The document titled “WECC Variable Generation Planning Reference Book”. This book is divided into two volumes; one is the main document (volume 1)and the other is appendices (volume 2). The main document is a collection of the best practices and the information regarding the application and impact of variables generation on power system planning. This volume (appendices) has additional information on the following topics: Probabilistic load flow problems. 2. Additional useful indices. 3. high-impact low-frequency (HILF) events. 4. Examples of wide-area nomograms. 5. Transmission line ratings, types of dynamic rating methods. 6. Relative costs per MW-km of different electric power transmission technologies. 7. Ultra-high voltage (UHV) transmission. 8.High voltage direct current (VSC-HVDC). 9. HVDC. 10. Rewiring of existing transmission lines. 11. High-temperature low sag (HTLS) conductors. 12. The direct method and energy functions for transient stability analysis in power systems. 13.Blackouts caused by voltage instability. 14. Algorithm for parameter continuation predictor-corrector methods. 15. Approximation techniques available for security regions. 16. Impacts of wind power on power system small signals stability. 17. FIDVR. 18. FACTS. 19. European planning standard and practices. 20. International experience in wind and solar energy sources. 21. Western Renewable Energy Zones (WREZ). 22. various energy storage technologies. 23. demand response. 24. BA consolidation and cooperation options. 25. generator power management requirements and 26. European planning guidelines.

  4. Automatic liver contouring for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Li, Dengwang; Kapp, Daniel S; Xing, Lei; Liu, Li

    2015-01-01

    To develop automatic and efficient liver contouring software for planning 3D-CT and four-dimensional computed tomography (4D-CT) for application in clinical radiation therapy treatment planning systems.The algorithm comprises three steps for overcoming the challenge of similar intensities between the liver region and its surrounding tissues. First, the total variation model with the L1 norm (TV-L1), which has the characteristic of multi-scale decomposition and an edge-preserving property, is used for removing the surrounding muscles and tissues. Second, an improved level set model that contains both global and local energy functions is utilized to extract liver contour information sequentially. In the global energy function, the local correlation coefficient (LCC) is constructed based on the gray level co-occurrence matrix both of the initial liver region and the background region. The LCC can calculate the correlation of a pixel with the foreground and background regions, respectively. The LCC is combined with intensity distribution models to classify pixels during the evolutionary process of the level set based method. The obtained liver contour is used as the candidate liver region for the following step. In the third step, voxel-based texture characterization is employed for refining the liver region and obtaining the final liver contours.The proposed method was validated based on the planning CT images of a group of 25 patients undergoing radiation therapy treatment planning. These included ten lung cancer patients with normal appearing livers and ten patients with hepatocellular carcinoma or liver metastases. The method was also tested on abdominal 4D-CT images of a group of five patients with hepatocellular carcinoma or liver metastases. The false positive volume percentage, the false negative volume percentage, and the dice similarity coefficient between liver contours obtained by a developed algorithm and a current standard delineated by the expert group

  5. Illinois statewide gas utility plan, 1993-2002. Volume 1. Executive summary

    International Nuclear Information System (INIS)

    1992-12-01

    The second Illinois Statewide Natural Gas Utility Plan is a continuation of the Least-Cost Planning effort introduced by the Public Utilities Act of 1986. The purpose of the Plan, like its predecessor, is to provide a framework and a set of policies which will allow and encourage local distribution companies to develop least-cost plans consistent with the goals of the Act: to provide efficient, environmentally sound, reliable, and equitable public utility service at the least possible cost. The Plan assesses natural gas demand and supply under five scenarios for the period 1993-2002. Key issues related to the development of least-cost natural gas plans are identified, and policies for addressing the issues are developed. The rationale and potential for natural gas demand side management (DSM) programs and policies are explored, and recommendations made with respect to utility DSM capability-building and DSM cost-recovery

  6. National Energy Plan II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    This volume contains the Administration's second National Energy Plan, as required by section 801 of the Department of Energy Organization Act (Public Law 95-91). A second volume will contain an assessment of the environmental trends associated with the energy futures reported here. Detailed appendices to the Plan will be published separately. The eight chapters and their subtitles are: Crisis and Uncertainty in the World Energy Future (The Immediate Crisis and the Continuing Problem, The Emergence of the Energy Problem, The Uncertainties of the World Energy Future, World Oil Prices, Consequences for the U.S.); The U.S. Energy Future: The Implications for Policy (The Near-, Mid-, and Long-Term, The Strategy in Perspective); Conservation (Historical Changes in Energy Use, Post-Embargo Changes - In Detail, Conservation Policies and Programs, The Role of Conservation); Oil and Gas (Oil, Natural Gas); Coal and Nuclear (Coal, Nuclear, Policy for Coal and Nuclear Power); Solar and Other Inexhaustible Energy Sources (Solar Energy, Geothermal, Fusion, A Strategy for Inexhaustible Resources); Making Decisions Promptly and Fairly (Managing Future Energy Crises: Emergency Planning, Managing the Current Shortfall: The Iranian Response Plan, Managing the Long-Term Energy Problem: The Institutional Framework, Fairness in Energy Policy, Public Participation in the Development of Energy Policy); and NEP-II and the Future (The Second National Energy Plan and the Nation's Energy Future, The Second National Energy Plan and the Economy, Employment and Energy Policy, The Second National Energy Plan and Individuals, The Second National Energy Plan and Capital Markets, and The Second National Energy Plan and the Environment). (ERA citation 04:041097)

  7. Changes in Upper Airway Volume Following Orthognathic Surgery.

    Science.gov (United States)

    Marcussen, Lillian; Stokbro, Kasper; Aagaard, Esben; Torkov, Peter; Thygesen, Torben

    2017-01-01

    Reduced volume of the internal skeletal dimensions of the face is 1 of the main causes of obstructive sleep apnea, and attention to patients' airways is necessary when planning orthognathic treatment. This study aims to describe changes in upper airway volume following virtually planned orthognathic surgery.A retrospective pilot study was designed with 30 randomly selected patients (10 men and 20 women, aged 23.1 ± 6.8 years, molar-relations: 15 neutral, 8 distal, and 7 mesial). Cone-beam computed tomography scans were performed before surgery and 1 week following surgery. The authors did total upper airway volume measurements and obtained 1-mm slices at vertical levels in the velo-, oro-, and hypopharynx and at the smallest visible cross-section.Measurements before and after surgery were compared using Student t test.After orthognathic surgery, the minimum cross-sectional area at the vertical level increased from 83 mm ± 33 before surgery to 102 mm ± 36 after surgery (P = 0.019). In patients with neutral and distal occlusions, the minimum cross-sectional slice volume increased in 87% but in only 57% with mesial occlusion.The present findings suggest that orthognathic surgery increases upper airway volume parameters, but a few patients have continued impairment of the airways following orthognathic surgery. Further studies are needed to confirm an individual surgical planning approach that potentially could bring the minimum cross sectional area out of the risk zone.

  8. Ovarian volume throughout life

    DEFF Research Database (Denmark)

    Kelsey, Thomas W; Dodwell, Sarah K; Wilkinson, A Graham

    2013-01-01

    conception to 82 years of age. This model shows that 69% of the variation in ovarian volume is due to age alone. We have shown that in the average case ovarian volume rises from 0.7 mL (95% CI 0.4-1.1 mL) at 2 years of age to a peak of 7.7 mL (95% CI 6.5-9.2 mL) at 20 years of age with a subsequent decline...... to about 2.8 mL (95% CI 2.7-2.9 mL) at the menopause and smaller volumes thereafter. Our model allows us to generate normal values and ranges for ovarian volume throughout life. This is the first validated normative model of ovarian volume from conception to old age; it will be of use in the diagnosis......The measurement of ovarian volume has been shown to be a useful indirect indicator of the ovarian reserve in women of reproductive age, in the diagnosis and management of a number of disorders of puberty and adult reproductive function, and is under investigation as a screening tool for ovarian...

  9. Dosimetric consequences of the shift towards computed tomography guided target definition and planning for breast conserving radiotherapy

    Directory of Open Access Journals (Sweden)

    Korevaar Erik W

    2008-01-01

    Full Text Available Abstract Background The shift from conventional two-dimensional (2D to three-dimensional (3D-conformal target definition and dose-planning seems to have introduced volumetric as well as geometric changes. The purpose of this study was to compare coverage of computed tomography (CT-based breast and boost planning target volumes (PTV, absolute volumes irradiated, and dose delivered to the organs at risk with conventional 2D and 3D-conformal breast conserving radiotherapy. Methods Twenty-five patients with left-sided breast cancer were subject of CT-guided target definition and 3D-conformal dose-planning, and conventionally defined target volumes and treatment plans were reconstructed on the planning CT. Accumulated dose-distributions were calculated for the conventional and 3D-conformal dose-plans, taking into account a prescribed dose of 50 Gy for the breast plans and 16 Gy for the boost plans. Results With conventional treatment plans, CT-based breast and boost PTVs received the intended dose in 78% and 32% of the patients, respectively, and smaller volumes received the prescribed breast and boost doses compared with 3D-conformal dose-planning. The mean lung dose, the volume of the lungs receiving > 20 Gy, the mean heart dose, and volume of the heart receiving > 30 Gy were significantly less with conventional treatment plans. Specific areas within the breast and boost PTVs systematically received a lower than intended dose with conventional treatment plans. Conclusion The shift towards CT-guided target definition and planning as the golden standard for breast conserving radiotherapy has resulted in improved target coverage at the cost of larger irradiated volumes and an increased dose delivered to organs at risk. Tissue is now included into the breast and boost target volumes that was never explicitly defined or included with conventional treatment. Therefore, a coherent definition of the breast and boost target volumes is needed, based on

  10. Dosimetric consequences of the shift towards computed tomography guided target definition and planning for breast conserving radiotherapy

    International Nuclear Information System (INIS)

    Laan, Hans Paul van der; Dolsma, Wil V; Maduro, John H; Korevaar, Erik W; Langendijk, Johannes A

    2008-01-01

    The shift from conventional two-dimensional (2D) to three-dimensional (3D)-conformal target definition and dose-planning seems to have introduced volumetric as well as geometric changes. The purpose of this study was to compare coverage of computed tomography (CT)-based breast and boost planning target volumes (PTV), absolute volumes irradiated, and dose delivered to the organs at risk with conventional 2D and 3D-conformal breast conserving radiotherapy. Twenty-five patients with left-sided breast cancer were subject of CT-guided target definition and 3D-conformal dose-planning, and conventionally defined target volumes and treatment plans were reconstructed on the planning CT. Accumulated dose-distributions were calculated for the conventional and 3D-conformal dose-plans, taking into account a prescribed dose of 50 Gy for the breast plans and 16 Gy for the boost plans. With conventional treatment plans, CT-based breast and boost PTVs received the intended dose in 78% and 32% of the patients, respectively, and smaller volumes received the prescribed breast and boost doses compared with 3D-conformal dose-planning. The mean lung dose, the volume of the lungs receiving > 20 Gy, the mean heart dose, and volume of the heart receiving > 30 Gy were significantly less with conventional treatment plans. Specific areas within the breast and boost PTVs systematically received a lower than intended dose with conventional treatment plans. The shift towards CT-guided target definition and planning as the golden standard for breast conserving radiotherapy has resulted in improved target coverage at the cost of larger irradiated volumes and an increased dose delivered to organs at risk. Tissue is now included into the breast and boost target volumes that was never explicitly defined or included with conventional treatment. Therefore, a coherent definition of the breast and boost target volumes is needed, based on clinical data confirming tumour control probability and normal

  11. Experimental validation of hyperthermia SAR treatment planning using MR B1+ imaging

    International Nuclear Information System (INIS)

    Berg, Cornelis A T van den; Bartels, Lambertus W; Leeuw, Astrid A C De; Lagendijk, Jan J W; Kamer, Jeroen B Van de

    2004-01-01

    In this paper the concept of using B 1+ imaging as a means to validate SAR models for radiofrequency hyperthermia is presented. As in radiofrequency hyperthermia, in common clinical MR imaging which applies RF frequencies between 64 and 128 MHz, the RF field distribution inside a patient is largely determined by the dielectric distribution of the anatomy. Modern MR imaging techniques allow measurement of the RF magnetic field component B 1+ making it possible to measure at high resolution the dielectric interaction of the RF field with the patient. Given these considerations, we propose to use MR imaging to verify the validity of our dielectric patient model used for SAR models of radiofrequency hyperthermia. The aim of this study was to investigate the feasibility of this concept by performing B 1+ measurements and simulations on cylindrical split phantoms consisting of materials with dielectric properties similar to human tissue types. Important topics of investigation were the accuracy and sensitivity of B 1+ measurements and the validity of the electric model of the MR body coil. The measurements were performed on a clinical 1.5 T MR scanner with its quadrature body coil operating at 64 MHz. It was shown that even small B 1+ variations of 2 to 5% could be measured reliably in the phantom experiments. An electrical model of the transmit coil was implemented on our FDTD-based hyperthermia treatment planning platform and the RF field distributions were calculated assuming an idealized quadrature current distribution in the coil. A quantitatively good correlation between measurements and simulations was found for phantoms consisting of water and oil, while highly conductive phantoms show considerable deviations. However, assuming linear excitation for these conductive phantoms resulted in good correspondence. As an explanation it is suggested that the coil is being detuned due to the inductive nature of the conductive phantoms, breaking up the phase difference of

  12. Waste isolation in the U.S., technical programs and public education. Volume 2 - low level waste, volume reduction methodologies and economics. Vol. 2

    International Nuclear Information System (INIS)

    Post, R.G.

    1984-01-01

    This volume presents information regarding low-level waste, volume reduction methodologies and economics. Topics include: public education on nuclear waste; economics of low-level waste management systems; operating experience with advanced volume reduction techniques; solidification of waste; operating experience with advanced volume reduction techniques--incineration; regional plans for the disposal of low-level waste; radwaste system modifications at nuclear power plants; operating experience with advanced volume reduction techniques--operations and on-site storage issues; and economic impact of 10CFR61

  13. Procedural issues in the development of a production plan in the petroleum transport computerized system of plan projects

    Energy Technology Data Exchange (ETDEWEB)

    German, V T; Karlikov, Y P; Papeev, V M; Samorodkin, V D; Vasil' ev, Y I

    1980-01-01

    The process of planning petroleum transportation must be described by a model that may be used to vary the distribution of the volumes of oil transported and to organize the oil flows so as to satisfy users requiring a particular volume of unprocessed petroleum. By means of the studies performed here, a number of conclusions may be drawn: 1. Available algorithms make it possible to compute the detailed network-wide indicators for petroleum transportation in the annual planning model; determine the capacities needed for individual members of the network; and create the necessary list of output documents for compliation of the tenative plan of production for oil transport; 2. An implementation of the oil transport plan using the specified route method should be based on an heuristic approach (a route is specified by a specialist or the routes of the current year are used), thereby allowing us to obtain the necessary production plans.

  14. Brain volume measurement using three-dimensional magnetic resonance images

    International Nuclear Information System (INIS)

    Ishimaru, Yoshihiro

    1996-01-01

    This study was designed to validate accurate measurement method of human brain volume using three dimensional (3D) MRI data on a workstation, and to establish optimal correcting method of human brain volume on diagnosis of brain atrophy. 3D MRI data were acquired by fast SPGR sequence using 1.5 T MR imager. 3D MRI data were segmented by region growing method and 3D image was displayed by surface rendering method on the workstation. Brain volume was measured by the volume measurement function of the workstation. In order to validate the accurate measurement method, phantoms and a specimen of human brain were examined. Phantom volume was measured by changing the lower level of threshold value. At the appropriate threshold value, percentage of error of phantoms and the specimen were within 0.6% and 0.08%, respectively. To establish the optimal correcting method, 130 normal volunteers were examined. Brain volumes corrected with height weight, body surface area, and alternative skull volume were evaluated. Brain volume index, which is defined as dividing brain volume by alternative skull volume, had the best correlation with age (r=0.624, p<0.05). No gender differences was observed in brain volume index in contrast to in brain volume. The clinical usefulness of this correcting method for brain atrophy diagnosis was evaluated in 85 patients. Diagnosis by 2D spin echo MR images was compared with brain volume index. Diagnosis of brain atrophy by 2D MR image was concordant with the evaluation by brain volume index. These results indicated that this measurement method had high accuracy, and it was important to set the appropriate threshold value. Brain volume index was the appropriate indication for evaluation of human brain volume, and was considered to be useful for the diagnosis of brain atrophy. (author)

  15. Consideration of the volume dependence of tolerance doses

    International Nuclear Information System (INIS)

    Gremmel, H.; Wendhausen, H.

    1977-01-01

    A general formula for consideration of the dependence of tolerance doses upon volume is obtained by mathematical evaluation of known skin tolerance doses. The validity for different organs is verified using available data of literature. It is recommended to introduce the volume dependence into the Ellis-formula for tolerance doses. (orig.) [de

  16. Savannah River Site approved site treatment plan, 2000 annual update

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, B.

    2000-04-20

    The Compliance Plan Volume (Volume 1) identifies project activity schedule milestones for achieving compliance with Land Disposal Restrictions. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume 2) and is provided for information.

  17. Savannah River Site Approved Site Treatment Plan, 1998 Annual Update

    International Nuclear Information System (INIS)

    Lawrence, B.

    1999-01-01

    The Compliance Plan Volume (Volume I) identifies project activity schedule milestones for achieving compliance with Land Disposal Restrictions. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume II) and is provided for information

  18. Savannah River Site approved site treatment plan, 2000 annual update

    International Nuclear Information System (INIS)

    Lawrence, B.

    2000-01-01

    The Compliance Plan Volume (Volume 1) identifies project activity schedule milestones for achieving compliance with Land Disposal Restrictions. Information regarding the technical evaluation of treatment options for SRS mixed wastes is contained in the Background Volume (Volume 2) and is provided for information

  19. National Waste Terminal Storage Program: configuration management plan. Volume II. Plan description

    International Nuclear Information System (INIS)

    1977-05-01

    Purpose of the Configuration Management Plan is to provide the management discipline through which the integrity and continuity of program cost and schedule trade-off decisions which are made concerning the site selections and facilities performance, producibility, operability and supportability are recorded, communicated, and controlled by the Office of Waste Isolation

  20. NOTE: Optimal needle arrangement for intraoperative planning in permanent I-125 prostate implants

    Science.gov (United States)

    Thompson, S. A.; Fung, A. Y. C.; Zaider, M.

    2002-08-01

    One limitation of intraoperative planning of permanent prostate implants is that needles must already be in the gland before planning images are acquired. Improperly placed needles often restrict the capability of generating optimal seed placement. We developed guiding principles for the proper layout of needles within the treatment volume. The Memorial Sloan-Kettering Cancer Center planning system employs a genetic algorithm to find the optimal seed implantation pattern consistent with pre-assigned constraints (needle geometry, uniformity, conformity and the avoidance of high doses to urethra and rectum). Ultrasound volumes for twelve patients with I-125 implants were used to generate six plans per patient (total 72 plans) with different needle arrangements. The plans were evaluated in terms of V100 (percentage prostate volume receiving at least the prescription dose), U135 (percentage urethra volume receiving at least 135% of prescription dose), and CI (conformity index, the ratio of treatment volume to prescription dose volume.) The method termed POSTCTR, in which needles were placed on the periphery of the largest ultrasound slice and posterior central needles were placed as needed, consistently gave superior results for all prostate sizes. Another arrangement, labelled POSTLAT, where the needles were placed peripherally with additional needles in the posterior lateral lobes, also gave satisfactory results. We advocate two needle arrangements, POSTCTR and POSTLAT, with the former giving better results.

  1. Dosimetric impact of prostate volume change between CT-based HDR brachytherapy fractions

    International Nuclear Information System (INIS)

    Kim, Yongbok; Hsu, I-C.; Lessard, Etienne; Vujic, Jasmina; Pouliot, Jean

    2004-01-01

    Purpose: The objective is to evaluate the prostate volume change and its dosimetric consequences after the insertion of catheters for high-dose-rate brachytherapy. Methods and Materials: For 13 consecutive patients, a spiral CT scan was acquired before each of the 2 fractions, separated on average by 20 hours. The coordinates of the catheters were obtained on 3 axial CT slices corresponding to apex, mid portion, and base portion of the prostate. A mathematical expansion model was used to evaluate the change of prostate volumes between the 2 fractions. It is based on the difference in the cube of the average distance between the centroid and catheter positions. The variation of implant dose-volume histograms between fractions was computed for plans produced by either inverse planning based on simulated annealing or geometric optimization. Results: The average magnitude of either increase or reduction in prostate volume was 7.8% (range, 2-17%). This volume change corresponds to an average prostate radius change of only 2.5% (range, 0.7-5.4%). For 5 patients, the prostate volume increased on average by 9% (range, 2-17%), whereas a reduction was observed for 8 patients by an average of 7% (range, 2-13%). More variation was observed at the prostate base than at mid or apex gland. The comparison of implant dose-volume histograms showed a small reduction of V100 receiving the prescription dose, with an average of 3.5% (range, 0.5-12%) and 2.2% (range, 1-6%) for inverse planning based on our simulated annealing and geometric optimization plans, respectively. Conclusion: Small volume change was observed between treatment fractions. This translates into small changes in dose delivered to the prostate volume

  2. A knowledge-based approach to improving and homogenizing intensity modulated radiation therapy planning quality among treatment centers: an example application to prostate cancer planning.

    Science.gov (United States)

    Good, David; Lo, Joseph; Lee, W Robert; Wu, Q Jackie; Yin, Fang-Fang; Das, Shiva K

    2013-09-01

    Intensity modulated radiation therapy (IMRT) treatment planning can have wide variation among different treatment centers. We propose a system to leverage the IMRT planning experience of larger institutions to automatically create high-quality plans for outside clinics. We explore feasibility by generating plans for patient datasets from an outside institution by adapting plans from our institution. A knowledge database was created from 132 IMRT treatment plans for prostate cancer at our institution. The outside institution, a community hospital, provided the datasets for 55 prostate cancer cases, including their original treatment plans. For each "query" case from the outside institution, a similar "match" case was identified in the knowledge database, and the match case's plan parameters were then adapted and optimized to the query case by use of a semiautomated approach that required no expert planning knowledge. The plans generated with this knowledge-based approach were compared with the original treatment plans at several dose cutpoints. Compared with the original plan, the knowledge-based plan had a significantly more homogeneous dose to the planning target volume and a significantly lower maximum dose. The volumes of the rectum, bladder, and femoral heads above all cutpoints were nominally lower for the knowledge-based plan; the reductions were significantly lower for the rectum. In 40% of cases, the knowledge-based plan had overall superior (lower) dose-volume histograms for rectum and bladder; in 54% of cases, the comparison was equivocal; in 6% of cases, the knowledge-based plan was inferior for both bladder and rectum. Knowledge-based planning was superior or equivalent to the original plan in 95% of cases. The knowledge-based approach shows promise for homogenizing plan quality by transferring planning expertise from more experienced to less experienced institutions. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Business plan: Supplemental draft environmental impact statement. Volume 2. Appendices

    International Nuclear Information System (INIS)

    1995-02-01

    This document contains the appendices for the Bonneville Power Administration (BPA) Business Plan: Supplemental Draft Environmental Impact Statement. Included are: BPA products and services; Rate design; Methodology and assumptions for numerical analysis; Retail utility operations; Comments and responses to the draft business plan EIS

  4. Business Plan : Supplemental Draft Environmental Impact Statement, Volume 2, Appendices.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1995-02-01

    This document contains the appendices for the Bonneville Power Administration (BPA) Business Plan: Supplemental Draft Environmental Impact Statement. Included are: BPA products and services; Rate design; Methodology and assumptions for numerical analysis; Retail utility operations; Comments and responses to the draft business plan EIS.

  5. Plan Validation Using DES and Agent-based Simulation

    National Research Council Canada - National Science Library

    Wong, Teck H; Ong, Kim S

    2008-01-01

    .... This thesis explores the possibility of using a multi-agent system (MAS) to generate the aggressor's air strike plans, which could be coupled with a low resolution Discrete Event Simulation (DES...

  6. Special nuclear material inventory sampling plans

    International Nuclear Information System (INIS)

    Vaccaro, H.S.; Goldman, A.S.

    1987-01-01

    This paper presents improved procedures for obtaining statistically valid sampling plans for nuclear facilities. The double sampling concept and methods for developing optimal double sampling plans are described. An algorithm is described that is satisfactory for finding optimal double sampling plans and choosing appropriate detection and false alarm probabilities

  7. Prediction of resource volumes at untested locations using simple local prediction models

    Science.gov (United States)

    Attanasi, E.D.; Coburn, T.C.; Freeman, P.A.

    2006-01-01

    This paper shows how local spatial nonparametric prediction models can be applied to estimate volumes of recoverable gas resources at individual undrilled sites, at multiple sites on a regional scale, and to compute confidence bounds for regional volumes based on the distribution of those estimates. An approach that combines cross-validation, the jackknife, and bootstrap procedures is used to accomplish this task. Simulation experiments show that cross-validation can be applied beneficially to select an appropriate prediction model. The cross-validation procedure worked well for a wide range of different states of nature and levels of information. Jackknife procedures are used to compute individual prediction estimation errors at undrilled locations. The jackknife replicates also are used with a bootstrap resampling procedure to compute confidence bounds for the total volume. The method was applied to data (partitioned into a training set and target set) from the Devonian Antrim Shale continuous-type gas play in the Michigan Basin in Otsego County, Michigan. The analysis showed that the model estimate of total recoverable volumes at prediction sites is within 4 percent of the total observed volume. The model predictions also provide frequency distributions of the cell volumes at the production unit scale. Such distributions are the basis for subsequent economic analyses. ?? Springer Science+Business Media, LLC 2007.

  8. A case study of IMRT planning (Plan B) subsequent to a previously treated IMRT plan (Plan A)

    International Nuclear Information System (INIS)

    2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" data-affiliation=" (Department of Medical Physics and 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" >Cao, F; 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" data-affiliation=" (Department of Medical Physics and 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" >Leong, C; 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" data-affiliation=" (Department of Medical Physics and 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" >Schroeder, J; 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" data-affiliation=" (Department of Medical Physics and 2Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada))" >Lee, B

    2014-01-01

    Background and purpose: Treatment of the contralateral neck after previous ipsilateral intensity modulated radiation therapy (IMRT) for head and neck cancer is a challenging problem. We have developed a technique that limits the cumulative dose to the spinal cord and brainstem while maximizing coverage of a planning target volume (PTV) in the contralateral neck. Our case involves a patient with right tonsil carcinoma who was given ipsilateral IMRT with 70Gy in 35 fractions (Plan A). A left neck recurrence was detected 14 months later. The patient underwent a neck dissection followed by postoperative left neck radiation to a dose of 66 Gy in 33 fractions (Plan B). Materials and Methods: The spinal cord-brainstem margin (SCBM) was defined as the spinal cord and brainstem with a 1.0 cm margin. Plan A was recalculated on the postoperative CT scan but the fluence outside of SCBM was deleted. A further modification of Plan A resulted in a base plan that was summed with Plan B to evaluate the cumulative dose received by the spinal cord and brainstem. Plan B alone was used to evaluate for coverage of the contralateral neck PTV. Results: The maximum cumulative doses to the spinal cord with 0.5cm margin and brainstem with 0.5cm margin were 51.96 Gy and 45.60 Gy respectively. For Plan B, 100% of the prescribed dose covered 95% of PTVb1. Conclusion: The use of a modified ipsilateral IMRT plan as a base plan is an effective way to limit the cumulative dose to the spinal cord and brainstem while enabling coverage of a PTV in the contralateral neck.

  9. SU-E-T-357: Semi-Automated Knowledge-Based Radiation Therapy (KBRT) Planning for Head-And-Neck Cancer (HNC): Can KBRT Plans Achieve Better Results Than Manual Planning?

    International Nuclear Information System (INIS)

    Lutzky, C; Grzetic, S; Lo, J; Das, S

    2014-01-01

    Purpose: Knowledge Based Radiation Therapy Treatment (KBRT) planning can be used to semi-automatically generate IMRT plans for new patients using constraints derived from previously manually-planned, geometrically similar patients. We investigate whether KBRT plans can achieve greater dose sparing than manual plans using optimized, organspecific constraint weighting factors. Methods: KBRT planning of HNC radiotherapy cases geometrically matched each new (query) case to one of the 105 clinically approved plans in our database. The dose distribution of the planned match was morphed to fit the querys geometry. Dose-volume constraints extracted from the morphed dose distribution were used to run the IMRT optimization with no user input. In the first version, all constraints were multiplied by a weighting factor of 0.7. The weighting factors were then systematically optimized (in order of OARs with increasing separation from the target) to maximize sparing to each OAR without compromising other OARs. The optimized, second version plans were compared against the first version plans and the clinically approved plans for 45 unilateral/bilateral target cases using the dose metrics: mean, median and maximum (brainstem and cord) doses. Results: Compared to the first version, the second version significantly reduced mean/median contralateral parotid doses (>2Gy) for bilateral cases. Other changes between the two versions were not clinically meaningful. Compared to the original clinical plans, both bilateral and unilateral plans in the second version had lower average dose metrics for 5 of the 6 OARs. Compared to the original plans, the second version achieved dose sparing that was at least as good for all OARs and better for the ipsilateral parotid (bilateral) and oral cavity (bilateral/unilateral). Differences in planning target volume coverage metrics were not clinically significant. Conclusion: HNC-KBRT planning generated IMRT plans with at least equivalent dose sparing to

  10. SU-E-T-357: Semi-Automated Knowledge-Based Radiation Therapy (KBRT) Planning for Head-And-Neck Cancer (HNC): Can KBRT Plans Achieve Better Results Than Manual Planning?

    Energy Technology Data Exchange (ETDEWEB)

    Lutzky, C; Grzetic, S; Lo, J; Das, S [Duke University Medical Center, Durham, NC (United States)

    2014-06-01

    Purpose: Knowledge Based Radiation Therapy Treatment (KBRT) planning can be used to semi-automatically generate IMRT plans for new patients using constraints derived from previously manually-planned, geometrically similar patients. We investigate whether KBRT plans can achieve greater dose sparing than manual plans using optimized, organspecific constraint weighting factors. Methods: KBRT planning of HNC radiotherapy cases geometrically matched each new (query) case to one of the 105 clinically approved plans in our database. The dose distribution of the planned match was morphed to fit the querys geometry. Dose-volume constraints extracted from the morphed dose distribution were used to run the IMRT optimization with no user input. In the first version, all constraints were multiplied by a weighting factor of 0.7. The weighting factors were then systematically optimized (in order of OARs with increasing separation from the target) to maximize sparing to each OAR without compromising other OARs. The optimized, second version plans were compared against the first version plans and the clinically approved plans for 45 unilateral/bilateral target cases using the dose metrics: mean, median and maximum (brainstem and cord) doses. Results: Compared to the first version, the second version significantly reduced mean/median contralateral parotid doses (>2Gy) for bilateral cases. Other changes between the two versions were not clinically meaningful. Compared to the original clinical plans, both bilateral and unilateral plans in the second version had lower average dose metrics for 5 of the 6 OARs. Compared to the original plans, the second version achieved dose sparing that was at least as good for all OARs and better for the ipsilateral parotid (bilateral) and oral cavity (bilateral/unilateral). Differences in planning target volume coverage metrics were not clinically significant. Conclusion: HNC-KBRT planning generated IMRT plans with at least equivalent dose sparing to

  11. Multi-institutional Comparison of Intensity Modulated Radiation Therapy (IMRT) Planning Strategies and Planning Results for Nasopharyngeal Cancer

    Science.gov (United States)

    Park, Sung Ho; Park, Suk Won; Oh, Do Hoon; Choi, Youngmin; Kim, Jeung Kee; Ahn, Yong Chan; Park, Won; Suh, Hyun Sook; Lee, Rena; Bae, Hoonsik

    2009-01-01

    The intensity-modulated radiation therapy (IMRT) planning strategies for nasopharyngeal cancer among Korean radiation oncology facilities were investigated. Five institutions with IMRT planning capacity using the same planning system were invited to participate in this study. The institutions were requested to produce the best plan possible for 2 cases that would deliver 70 Gy to the planning target volume of gross tumor (PTV1), 59.4 Gy to the PTV2, and 51.5 Gy to the PTV3 in which elective irradiation was required. The advised fractionation number was 33. The planning parameters, resultant dose distributions, and biological indices were compared. We found 2-3-fold variations in the volume of treatment targets. Similar degree of variation was found in the delineation of normal tissue. The physician-related factors in IMRT planning had more influence on the plan quality. The inhomogeneity index of PTV dose ranged from 4 to 49% in Case 1, and from 5 to 46% in Case 2. Variation in tumor control probabilities for the primary lesion and involved LNs was less marked. Normal tissue complication probabilities for parotid glands and skin showed marked variation. Results from this study suggest that greater efforts in providing training and continuing education in terms of IMRT planning parameters usually set by physician are necessary for the successful implementation of IMRT. PMID:19399266

  12. Measurement of liver volume by emission computed tomography

    International Nuclear Information System (INIS)

    Kan, M.K.; Hopkins, G.B.

    1979-01-01

    In 22 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography (ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-mean-square error of less than 6% between duplicate measurements in 15 individuals. The volume measurements were validated by the use of phantoms

  13. Effect of carboxymethylcellulose on the rheological and filtration properties of bentonite clay samples determined by experimental planning and statistical analysis

    Directory of Open Access Journals (Sweden)

    B. M. A. Brito

    Full Text Available Abstract Over the past few years, considerable research has been conducted using the techniques of mixture delineation and statistical modeling. Through this methodology, applications in various technological fields have been found/optimized, especially in clay technology, leading to greater efficiency and reliability. This work studied the influence of carboxymethylcellulose on the rheological and filtration properties of bentonite dispersions to be applied in water-based drilling fluids using experimental planning and statistical analysis for clay mixtures. The dispersions were prepared according to Petrobras standard EP-1EP-00011-A, which deals with the testing of water-based drilling fluid viscosifiers for oil prospecting. The clay mixtures were transformed into sodic compounds, and carboxymethylcellulose additives of high and low molar mass were added, in order to improve their rheology and filtrate volume. Experimental planning and statistical analysis were used to verify the effect. The regression models were calculated for the relation between the compositions and the following rheological properties: apparent viscosity, plastic viscosity, and filtrate volume. The significance and validity of the models were confirmed. The results showed that the 3D response surfaces of the compositions with high molecular weight carboxymethylcellulose added were the ones that most contributed to the rise in apparent viscosity and plastic viscosity, and that those with low molecular weight were the ones that most helped in the reduction of the filtrate volume. Another important observation is that the experimental planning and statistical analysis can be used as an important auxiliary tool to optimize the rheological properties and filtrate volume of bentonite clay dispersions for use in drilling fluids when carboxymethylcellulose is added.

  14. High integrity software for nuclear power plants: Candidate guidelines, technical basis and research needs. Main report, Volume 2

    International Nuclear Information System (INIS)

    Seth, S.; Bail, W.; Cleaves, D.; Cohen, H.; Hybertson, D.; Schaefer, C.; Stark, G.; Ta, A.; Ulery, B.

    1995-06-01

    The work documented in this report was performed in support of the US Nuclear Regulatory Commission to examine the technical basis for candidate guidelines that could be considered in reviewing and evaluating high integrity computer e following software development and assurance activities: Requirements specification; design; coding; verification and validation, inclukding static analysis and dynamic testing; safety analysis; operation and maintenance; configuration management; quality assurance; and planning and management. Each activity (framework element) was subdivided into technical areas (framework subelements). The report describes the development of approximately 200 candidate guidelines that span the entire ran e identification, categorization and prioritization of technical basis for those candidate guidelines; and the identification, categorization and prioritization of research needs for improving the technical basis. The report has two volumes: Volume 1, Executive Summary includes an overview of the framwork and of each framework element, the complete set of candidate guidelines, the results of the assessment of the technical basis for each candidate guideline, and a discussion of research needs that support the regulatory function; this document, Volume 2, is the main report

  15. High integrity software for nuclear power plants: Candidate guidelines, technical basis and research needs. Main report, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Seth, S.; Bail, W.; Cleaves, D.; Cohen, H.; Hybertson, D.; Schaefer, C.; Stark, G.; Ta, A.; Ulery, B. [Mitre Corp., McLean, VA (United States)

    1995-06-01

    The work documented in this report was performed in support of the US Nuclear Regulatory Commission to examine the technical basis for candidate guidelines that could be considered in reviewing and evaluating high integrity computer e following software development and assurance activities: Requirements specification; design; coding; verification and validation, inclukding static analysis and dynamic testing; safety analysis; operation and maintenance; configuration management; quality assurance; and planning and management. Each activity (framework element) was subdivided into technical areas (framework subelements). The report describes the development of approximately 200 candidate guidelines that span the entire ran e identification, categorization and prioritization of technical basis for those candidate guidelines; and the identification, categorization and prioritization of research needs for improving the technical basis. The report has two volumes: Volume 1, Executive Summary includes an overview of the framwork and of each framework element, the complete set of candidate guidelines, the results of the assessment of the technical basis for each candidate guideline, and a discussion of research needs that support the regulatory function; this document, Volume 2, is the main report.

  16. Cone Beam CT Imaging Analysis of Interfractional Variations in Bladder Volume and Position During Radiotherapy for Bladder Cancer

    International Nuclear Information System (INIS)

    Yee, Don; Parliament, Matthew; Rathee, Satyapal; Ghosh, Sunita; Ko, Lawrence; Murray, Brad

    2010-01-01

    Purpose: To quantify daily bladder size and position variations during bladder cancer radiotherapy. Methods and Materials: Ten bladder cancer patients underwent daily cone beam CT (CBCT) imaging of the bladder during radiotherapy. Bladder and planning target volumes (bladder/PTV) from CBCT and planning CT scans were compared with respect to bladder center-of-mass shifts in the x (lateral), y (anterior-posterior), and z (superior-inferior) coordinates, bladder/PTV size, bladder/PTV margin positions, overlapping areas, and mutually exclusive regions. Results: A total of 262 CBCT images were obtained from 10 bladder cancer patients. Bladder center of mass shifted most in the y coordinate (mean, -0.32 cm). The anterior bladder wall shifted the most (mean, -0.58 cm). Mean ratios of CBCT-derived bladder and PTV volumes to planning CT-derived counterparts were 0.83 and 0.88. The mean CBCT-derived bladder volume (± standard deviation [SD]) outside the planning CT counterpart was 29.24 cm 3 (SD, 29.71 cm 3 ). The mean planning CT-derived bladder volume outside the CBCT counterpart was 47.74 cm 3 (SD, 21.64 cm 3 ). The mean CBCT PTV outside the planning CT-derived PTV was 47.35 cm 3 (SD, 36.51 cm 3 ). The mean planning CT-derived PTV outside the CBCT-derived PTV was 93.16 cm 3 (SD, 50.21). The mean CBCT-derived bladder volume outside the planning PTV was 2.41 cm 3 (SD, 3.97 cm 3 ). CBCT bladder/ PTV volumes significantly differed from planning CT counterparts (p = 0.047). Conclusions: Significant variations in bladder and PTV volume and position occurred in patients in this trial.

  17. Ongoing development of digital radiotherapy plan review tools

    International Nuclear Information System (INIS)

    Ebert, M.A.; Hatton, J.; Cornes, D.

    2011-01-01

    Full text: To describe ongoing development of software to support the review of radiotherapy treatment planning system (TPS) data. The 'SWAN' software program was conceived in 2000 and initially developed for the RADAR (TROG 03.04) prostate radiotherapy trial. Validation of the SWAN program has been occurring via implementation by TROG in support of multiple clinical trials. Development has continued and the SWAN software program is now supported by modular components which comprise the 'SW AN system'. This provides a comprehensive set of tools for the review, analysis and archive of TPS exports. The SWAN system has now been used in support of over 20 radiotherapy trials and to review the plans of over 2,000 trial participants. The use of the system for the RADAR trial is now culminating in the derivation of dose-outcomes indices for prostate treatment toxicity. Newly developed SWAN tools include enhanced remote data archive/retrieval, display of dose in both relative and absolute modes, and interfacing to a Matlab-based add-on ('VAST') that allows quantitative analysis of delineated volumes including regional overlap statistics for multi-observer studies. Efforts are continuing to develop the SWAN system in the context of international collaboration aimed at harmonising the quality-assurance activities of collaborative trials groups. Tools such as the SWAN system are essential for ensuring the collection of accurate and reliable evidence to guide future radiotherapy treatments. One of the principal challenges of developing such a tool is establishing a development path that will ensure its validity and applicability well into the future.

  18. Geometrical Comparison Measures for Tumor Delineation, what do they mean for the Actual Dosis Plan?

    DEFF Research Database (Denmark)

    Hollensen, Christian; Persson, G.; Højgaard, L.

    2012-01-01

    Purpose/Objective: Gross tumour volume (GTV) delineation is central for radiotherapy planning. It provides the basis of the clinical target volume and finally the planning target volume (PTV) which is used for dose optimization. GTV delineations are prone to intermethod and inter......observer variation. In clinical studies this variation is commonly represented by geometrical volume comparison measures (GVCMs) as volume assessment, centre of mass and overlap. The correlation between these measures and the radiotherapy plan are however unclear. The aim of the present study is to investigate...... the correlation between GVCMs and the radiotherapy plans of patients with peripheral lung tumours. Materials and Methods: Peripheral lung tumours of 10 patients referred for stereotactic body radiotherapy in 2008 were delineated by 3 radiologists and 3 oncologists. From these GTV delineations 6 different...

  19. Using face validity to recognize empirical community observations.

    Science.gov (United States)

    Gaber, John; Gaber, Sharon L

    2010-05-01

    There is a growing interest among international planning scholars to explore community participation in the plan making process from a qualitative research approach. In this paper the research assessment tool "face validity" is discussed as one way to help planners decipher when the community is sharing empirically grounded observations that can advance the applicability of the plan making process. Face validity provides a common sense assessment of research conclusions. It allows the assessor to look at an entire research project and ask: "on the face of things, does this research make sense?" With planners listening to citizen comments with an ear for face validity observations, holds open the opportunity for government to empirically learn from the community to see if they "got it right." And if not, to chart out a course on how they can get it right. Copyright 2009 Elsevier Ltd. All rights reserved.

  20. A spreadsheet to determine the volume ratio for target and breast in partial breast irradiation

    International Nuclear Information System (INIS)

    Kron, T.; Willis, D.; Miller, J.; Hubbard, P.; Oliver, M.; Chua, B.

    2009-01-01

    Full text: The technical feasibility of Partial Breast Irradiation (PBI) using external beam radiotherapy depends on the ratio between the evaluation planning target volume (PTV e val) and the whole breast volume (PBI volume ratio = PVR). We aimed to develop a simple method to determine PVR using measurements performed at the time of the planning CT scan. A PVR calculation tool was developed using a Microsoft Excel spreadsheet to determine the PTV from three orthogonal dimensions of the seroma cavity and a given margin on the CT scans. The breast volume is estimated from the separation and breast height in five equally spaced CT slices. The PTV e val and whole breast volume were determined for 29 patients from two centres using the spreadsheet calculation tool and compared to volumes delineated on computerised treatment planning systems. Both the PTV e val and whole breast volumes were underestimated by approximately 25% using the spreadsheet. The resulting PVRs were 1.05 +/- 0.35 (mean +/- 1 S D) times larger than the ones determined from planning. Estimations of the PVR using the calculation tool were achievable in around 5 minutes at the time of CT scanning and allow a prompt decision on the suitability of the patients for PBI.

  1. White Rose development plan amendment production volume increase

    International Nuclear Information System (INIS)

    2006-09-01

    In January 2001, Husky Oil Operations Limited (Husky), in joint-venture with Petro-Canada, submitted a Benefits Plan for the White Rose Development to the Canada- Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB). This revised document provided the case for requesting an increase in the facility maximum daily production rate and the average annual production rate for the White Rose field from 100,000 barrels per day (bpd) as stated in the approved White Rose Development Plan to 140,000 bpd. In order to determine the potential for increasing oil production through the Floating Production, Storage and Offloading (FPSO) vessel, two things were considered, namely the proper reservoir management of the White Rose field to ensure optimum resource recovery, and the capacity of the FPSO topsides processing system and supporting utilities to accommodate increased production. This document presented a detailed review of all the implications of increased production on the South White Rose Reservoir. In addition, the results from FPSO performance testing were reviewed, including a study of options for de-bottlenecking the process plant on the topsides and capacity testing of selected process streams and support systems. Vibration analysis was conducted before and during performance testing in July 2006 and a small number of areas addressed. The document also addressed flow metering, resource management, certifying authority review, safety plan revisions, environmental effects, as well as benefits to Canada and Newfoundland. 21 tabs., 60 refs

  2. Sandia software guidelines, Volume 4: Configuration management

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-01

    This volume is one in a series of Sandia Software Guidelines for use in producing quality software within Sandia National Laboratories. This volume is based on the IEEE standard and guide for software configuration management. The basic concepts and detailed guidance on implementation of these concepts are discussed for several software project types. Example planning documents for both projects and organizations are included.

  3. Fully automatic guidance and control for rotorcraft nap-of-the-Earth flight following planned profiles. Volume 1: Real-time piloted simulation

    Science.gov (United States)

    Clement, Warren F.; Gorder, Peter J.; Jewell, Wayne F.

    1991-01-01

    Developing a single-pilot, all-weather nap-of-the-earth (NOE) capability requires fully automatic NOE (ANOE) navigation and flight control. Innovative guidance and control concepts are investigated in a four-fold research effort that: (1) organizes the on-board computer-based storage and real-time updating of NOE terrain profiles and obstacles in course-oriented coordinates indexed to the mission flight plan; (2) defines a class of automatic anticipative pursuit guidance algorithms and necessary data preview requirements to follow the vertical, lateral, and longitudinal guidance commands dictated by the updated flight profiles; (3) automates a decision-making process for unexpected obstacle avoidance; and (4) provides several rapid response maneuvers. Acquired knowledge from the sensed environment is correlated with the forehand knowledge of the recorded environment (terrain, cultural features, threats, and targets), which is then used to determine an appropriate evasive maneuver if a nonconformity of the sensed and recorded environments is observed. This four-fold research effort was evaluated in both fixed-based and moving-based real-time piloted simulations, thereby, providing a practical demonstration for evaluating pilot acceptance of the automated concepts, supervisory override, manual operation, and re-engagement of the automatic system. Volume one describes the major components of the guidance and control laws as well as the results of the piloted simulations. Volume two describes the complete mathematical model of the fully automatic guidance system for rotorcraft NOE flight following planned flight profiles.

  4. Impact of Different CT Slice Thickness on Clinical Target Volume for 3D Conformal Radiation Therapy

    International Nuclear Information System (INIS)

    Prabhakar, Ramachandran; Ganesh, Tharmar; Rath, Goura K.; Julka, Pramod K.; Sridhar, Pappiah S.; Joshi, Rakesh C.; Thulkar, Sanjay

    2009-01-01

    The purpose of this study was to present the variation of clinical target volume (CTV) with different computed tomography (CT) slice thicknesses and the impact of CT slice thickness on 3-dimensional (3D) conformal radiotherapy treatment planning. Fifty patients with brain tumors were selected and CT scans with 2.5-, 5-, and 10-mm slice thicknesses were performed with non-ionic contrast enhancement. The patients were selected with tumor volume ranging from 2.54 cc to 222 cc. Three-dimensional treatment planning was performed for all three CT datasets. The target coverage and the isocenter shift between the treatment plans for different slice thickness were correlated with the tumor volume. An important observation from our study revealed that for volume 25 cc, the target underdosage was less than 6.7% for 5-mm slice thickness and 8% for 10-mm slice thickness. For 3D conformal radiotherapy treatment planning (3DCRT), a CT slice thickness of 2.5 mm is optimum for tumor volume 25 cc

  5. Dependence of Achievable Plan Quality on Treatment Technique and Planning Goal Refinement: A Head-and-Neck Intensity Modulated Radiation Therapy Application

    International Nuclear Information System (INIS)

    Qi, X. Sharon; Ruan, Dan; Lee, Steve P.; Pham, Andrew; Kupelian, Patrick; Low, Daniel A.; Steinberg, Michael; Demarco, John

    2015-01-01

    Purpose: To develop a practical workflow for retrospectively analyzing target and normal tissue dose–volume endpoints for various intensity modulated radiation therapy (IMRT) delivery techniques; to develop technique-specific planning goals to improve plan consistency and quality when feasible. Methods and Materials: A total of 165 consecutive head-and-neck patients from our patient registry were selected and retrospectively analyzed. All IMRT plans were generated using the same dose–volume guidelines for TomoTherapy (Tomo, Accuray), TrueBeam (TB, Varian) using fixed-field IMRT (TB-IMRT) or RAPIDARC (TB-RAPIDARC), or Siemens Oncor (Siemens-IMRT, Siemens). A MATLAB-based dose–volume extraction and analysis tool was developed to export dosimetric endpoints for each patient. With a fair stratification of patient cohort, the variation of achieved dosimetric endpoints was analyzed among different treatment techniques. Upon identification of statistically significant variations, technique-specific planning goals were derived from dynamically accumulated institutional data. Results: Retrospective analysis showed that although all techniques yielded comparable target coverage, the doses to the critical structures differed. The maximum cord doses were 34.1 ± 2.6, 42.7 ± 2.1, 43.3 ± 2.0, and 45.1 ± 1.6 Gy for Tomo, TB-IMRT, TB-RAPIDARC, and Siemens-IMRT plans, respectively. Analyses of variance showed significant differences for the maximum cord doses but no significant differences for other selected structures among the investigated IMRT delivery techniques. Subsequently, a refined technique-specific dose–volume guideline for maximum cord dose was derived at a confidence level of 95%. The dosimetric plans that failed the refined technique-specific planning goals were reoptimized according to the refined constraints. We observed better cord sparing with minimal variations for the target coverage and other organ at risk sparing for the Tomo cases, and higher

  6. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-08-01

    Full Text Available Wei Wang, Jianbin Li, Yingjie Zhang, Qian Shao, Min Xu, Tingyong Fan, Jinzhi Wang Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Shandong, People’s Republic of China Background and purpose: To investigate the definition of planning target volumes (PTVs based on four-dimensional computed tomography (4DCT compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. Materials and methods: Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathing. The motions of primary tumors located in the proximal (group A, middle (group B, and distal (group C thoracic esophagus were obtained from the 4DCT scans. PTV3D was defined on 3DCT using the tumor motion measured based on 4DCT, PTV conventional (PTVconv was defined on 3DCT by adding a 1.0 cm margin to the clinical target volume, and PTV4D was defined as the union of the target volumes contoured on the ten phases of the 4DCT images. The centroid positions, volumetric differences, and dice similarity coefficients were evaluated for all PTVs. Results: The median centroid shifts between PTV3D and PTV4D and between PTVconv and PTV4D in all three dimensions were <0.3 cm for the three groups. The median size ratios of PTV4D to PTV3D were 0.80, 0.88, and 0.71, and PTV4D to PTVconv were 0.67, 0.73, and 0.76 (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The dice similarity coefficients were 0.87, 0.90, and 0.81 between PTV4D and PTV3D and 0.80, 0.84, and 0.83 between PTV4D and PTVconv (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The difference between the degree of inclusion of PTV4D in PTV3D and that of PTV4D in PTVconv was <2% for all groups. Compared with PTVconv, the amount of irradiated normal tissue

  7. Feasibility of dose planning using CBCT images combined with MSCT images for adaptive radiotherapy

    International Nuclear Information System (INIS)

    Usui, Keisuke; Kunieda, Etsuo; Ogawa, Koichi

    2013-01-01

    If a kilo-voltage cone-beam computed tomography (CBCT) system mounted on a linear accelerator becomes available for dose calculation, we can confirm the dose distribution of treatment in each day by referring it to the initially planned dose distribution. In this paper, we verified the validity of the calculation method using CBCT images combined with multi-slice CT images. To evaluate the accuracy of calculated dose distribution, γ analysis, distance-to-agreement analysis and dose-volume-histogram analysis were used as the conventional dose calculation methods using CBCT images. The results showed that the dose distribution calculated by our proposed method agreed with the initial treatment plan better compared with the other methods. In addition, our method was so stable that the calculated dose distribution was insensitive to variations in clinical conditions. We demonstrated the feasibility of our proposed method for adaptive radiotherapy. (author)

  8. New South Wales coal strategy. Volume 1 - strategic plan. Volume 2 - industry review

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    The committee has concluded that while the outlook for coal demand growth is less optimistic than it was in 1981, nonetheless significant additional opportunities will arise in the medium term and that proper planning will place New South Wales in a strong position to take advantage of them.

  9. SU-E-J-52: Validation of 3D Structure Projection Onto 2D DRR in Commercial Treatment Planning Systems.

    Science.gov (United States)

    Zhang, L; Court, L; Balter, P; Dong, L

    2012-06-01

    The use of structure overlay on setup DRRs can aid the image alignment procedure for daily image-guided setup procedures. However, the accuracy of a 3D region-of-interest (ROI) projected on a 2D digitally reconstructed radiograph (DRR) has rarely been evaluated quantitatively. The goal of this study is to test the accuracy of two commercial treatment planning systems (TPS) in producing overlay structures on setup DRRs. We designed a novel method to identify landmarks which were on the boundary of the projected ROI on a DRR. The 3D ROIvolume is composed of a stack of 2D curves. We first mathematically project each 2D curve onto a beams-eye-view (BEV) plane. Next, we detectthe boundary points of the projected curves. Those boundary points serve aslandmarks. Finally, we project the binary mask of the 3D ROI volume using ray tracing method onto the BEV plane. This projected binary mask is used to exclude the false landmarks. Once those landmarks are detected, wecompute the distance between the landmarks and ROI outlines from the TPS. We applied our validation method to 13 ROIs from a lung patient and 4 simulated ROIs on 2 BEV DRRs for two different TPS (Eclipse and Pinnacle). Average distance between the landmarks and ROIoutlines was 0.5mm for both Eclipse and Pinnacle approaches, which is close to the pixel resolution of the DRR. The maximum distance andaverage maximum distance was 2mm and 1 mm, respectively, for both TPS.The maximum distance occurred at points where the ROI curve has a sharpchange between slices. The accuracy of Eclipse and Pinnacle ROI projection method seems to be acceptable to within 1mm althoughprojection error can be as large as 2mm when structure shape has a sharp variation from one slice to the next. © 2012 American Association of Physicists in Medicine.

  10. Planning of elimination of emergency consequences

    Directory of Open Access Journals (Sweden)

    S. Kovalenko

    2015-05-01

    Full Text Available Introduction. The volume of useful information in the planning of elimination of emergency consequences process is reasonable to assess with calculatory problems and mathematical models. Materials and methods. The expert survey method is used to calculate quantitative values of probability and to determine the optimal solution before the information in condition is received. Results. It is determined that the quality of the solution of elimination emergency consequences depends primarily on the number of factors that are taken into account in particular circumstances of the situation; on the level of information readiness of control bodies to take decision to eliminate emergency consequences as soon as possible and to consider several options for achieving reasonableness and concreteness of a particular decision. The ratio between volume of useful information collected and processed during operation planning which is required for identifying optimal solution is calculated. This ratio allows to construct a graph of probability of identifying a solution in existing environment and probability value of identifying optimal solution before information in P*condition is obtained. This graph also shows the ratio volume of useful information collected and processed during operation planning and necessary volume of information for identifying optimal solution. Conclusion. The results of this research can be used for improving control bodies decisions to ensure safe working conditions for employees of food industry.

  11. 1995 Solid Waste 30-year volume summary

    International Nuclear Information System (INIS)

    Valero, O.J.; DeForest, T.J.; Templeton, K.J.

    1995-06-01

    This document, prepared by Pacific Northwest Laboratory (PNL) under the direction of Westinghouse Hanford Company (WHC), provides a description of the annual low-level mixed waste (LLMW) and transuranic/transuranic mixed solid waste (TRU-TRUM) volumes expected to be managed by Hanford's Solid Waste Central Waste Complex (CWC) over the next 30 years. The waste generation sources and waste categories are also described. This document is intended to be used as a reference for short- and long-term planning of the Hanford treatment, storage, and disposal (TSD) activities over the next several decades. By estimating the waste volumes that will be generated in the future, facility planners can determine the timing of key waste management activities, evaluate alternative treatment strategies, and plan storage and disposal capacities. In addition, this document can be used by other waste sites and the general public to gain a better understanding of the types and volumes of waste that will be managed at Hanford

  12. 1995 Solid Waste 30-year volume summary

    Energy Technology Data Exchange (ETDEWEB)

    Valero, O.J. [Westinghouse Hanford Co., Richland, WA (United States); DeForest, T.J.; Templeton, K.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-06-01

    This document, prepared by Pacific Northwest Laboratory (PNL) under the direction of Westinghouse Hanford Company (WHC), provides a description of the annual low-level mixed waste (LLMW) and transuranic/transuranic mixed solid waste (TRU-TRUM) volumes expected to be managed by Hanford`s Solid Waste Central Waste Complex (CWC) over the next 30 years. The waste generation sources and waste categories are also described. This document is intended to be used as a reference for short- and long-term planning of the Hanford treatment, storage, and disposal (TSD) activities over the next several decades. By estimating the waste volumes that will be generated in the future, facility planners can determine the timing of key waste management activities, evaluate alternative treatment strategies, and plan storage and disposal capacities. In addition, this document can be used by other waste sites and the general public to gain a better understanding of the types and volumes of waste that will be managed at Hanford.

  13. Magnetic Resonance Imaging and conformal radiotherapy: Characterization of MRI alone simulation for conformal radiotherapy. Development and evaluation of an automatic volumes of interest segmentation tool for prostate cancer radiotherapy

    International Nuclear Information System (INIS)

    Pasquier, David

    2006-01-01

    Radiotherapy is a curative treatment of malignant tumours. Radiotherapy techniques considerably evolved last years with the increasing integration of medical images in conformal radiotherapy. This technique makes it possible to elaborate a complex ballistics conforming to target volume and sparing healthy tissues. The examination currently used to delineate volumes of interest is Computed Tomography (CT), on account of its geometrical precision and the information that it provides on electronic densities needed to dose calculation. Magnetic Resonance Imaging (MRI) ensures a more precise delineation of target volumes in many locations, such as pelvis and brain. For pelvic tumours, the use of MRI needs image registration, which complicates treatment planning and poses the problem of the lack of in vivo standard method of validation. The obstacles in the use of MRI alone in treatment planning were evaluated. Neither geometrical distortion linked with the system and the patient nor the lack of information on electronic densities represent stumbling obstacles. Distortion remained low even in edge of large field of view on modern machines. The assignment of electronic densities to bone structures and soft tissues in MR images permitted to obtain equivalent dosimetry to that carried out on the original CT, with a good reproducibility and homogeneous distribution within target volume. The assignment of electronic densities could not be carried out using 20 MV photons and suitable ballistics. The development of Image Guided Radiotherapy could facilitate the use of MRI alone in treatment planning. Target volumes and organ at risk delineation is a time consuming task in radiotherapy planning. We took part in the development and evaluated a method of automatic and semi automatic delineation of volumes of interest from MRI images for prostate cancer radiotherapy. For prostate and organ at risk automatic delineation an organ model-based method and a seeded region growing method

  14. Data Management and Preservation Planning for Big Science

    Directory of Open Access Journals (Sweden)

    Juan Bicarregui

    2013-06-01

    Full Text Available ‘Big Science’ - that is, science which involves large collaborations with dedicated facilities, and involving large data volumes and multinational investments – is often seen as different when it comes to data management and preservation planning. Big Science handles its data differently from other disciplines and has data management problems that are qualitatively different from other disciplines. In part, these differences arise from the quantities of data involved, but possibly more importantly from the cultural, organisational and technical distinctiveness of these academic cultures. Consequently, the data management systems are typically and rationally bespoke, but this means that the planning for data management and preservation (DMP must also be bespoke.These differences are such that ‘just read and implement the OAIS specification’ is reasonable Data Management and Preservation (DMP advice, but this bald prescription can and should be usefully supported by a methodological ‘toolkit’, including overviews, case-studies and costing models to provide guidance on developing best practice in DMP policy and infrastructure for these projects, as well as considering OAIS validation, audit and cost modelling.In this paper, we build on previous work with the LIGO collaboration to consider the role of DMP planning within these big science scenarios, and discuss how to apply current best practice. We discuss the result of the MaRDI-Gross project (Managing Research Data Infrastructures – Big Science, which has been developing a toolkit to provide guidelines on the application of best practice in DMP planning within big science projects. This is targeted primarily at projects’ engineering managers, but intending also to help funders collaborate on DMP plans which satisfy the requirements imposed on them.

  15. Evaluation of Peritumoral Edema in the Delineation of Radiotherapy Clinical Target Volumes for Glioblastoma

    International Nuclear Information System (INIS)

    Chang, Eric L.; Akyurek, Serap; Avalos, Tedde C; Rebueno, Neal C; Spicer, Chris C; Garcia, John C; Famiglietti, Robin; Allen, Pamela K.; Chao, K.S. Clifford; Mahajan, Anita; Woo, Shiao Y.; Maor, Moshe H.

    2007-01-01

    Purpose: To evaluate the spatial relationship between peritumoral edema and recurrence pattern in patients with glioblastoma (GBM). Methods and Materials: Forty-eight primary GBM patients received three-dimensional conformal radiotherapy that did not intentionally include peritumoral edema within the clinical target volume between July 2000 and June 2001. All 48 patients have subsequently recurred, and their original treatment planning parameters were used for this study. New theoretical radiation treatment plans were created for the same 48 patients, based on Radiation Therapy Oncology Group (RTOG) target delineation guidelines that specify inclusion of peritumoral edema. Target volume and recurrent tumor coverage, as well as percent volume of normal brain irradiated, were assessed for both methods of target delineation using dose-volume histograms. Results: A comparison between the location of recurrent tumor and peritumoral edema volumes from all 48 cases failed to show correlation by linear regression modeling (r 2 0.0007; p = 0.3). For patients with edema >75 cm 3 , the percent volume of brain irradiated to 46 Gy was significantly greater in treatment plans that intentionally included peritumoral edema compared with those that did not (38% vs. 31%; p = 0.003). The pattern of failure was identical between the two sets of plans (40 central, 3 in-field, 3 marginal, and 2 distant recurrence). Conclusion: Clinical target volume delineation based on a 2-cm margin rather than on peritumoral edema did not seem to alter the central pattern of failure for patients with GBM. For patients with peritumoral edema >75 cm 3 , using a constant 2-cm margin resulted in a smaller median percent volume of brain being irradiated to 30 Gy, 46 Gy, and 50 Gy compared with corresponding theoretical RTOG plans that deliberately included peritumoral edema

  16. Functional image-based radiotherapy planning for non-small cell lung cancer: A simulation study

    International Nuclear Information System (INIS)

    Bates, Emma L.; Bragg, Christopher M.; Wild, Jim M.; Hatton, Matthew Q.F.; Ireland, Rob H.

    2009-01-01

    Background and purpose: To investigate the incorporation of data from single-photon emission computed tomography (SPECT) or hyperpolarized helium-3 magnetic resonance imaging ( 3 He-MRI) into intensity-modulated radiotherapy (IMRT) planning for non-small cell lung cancer (NSCLC). Material and methods: Seven scenarios were simulated that represent cases of NSCLC with significant functional lung defects. Two independent IMRT plans were produced for each scenario; one to minimise total lung volume receiving ≥20 Gy (V 20 ), and the other to minimise only the functional lung volume receiving ≥20 Gy (FV 20 ). Dose-volume characteristics and a plan quality index related to planning target volume coverage by the 95% isodose (V PTV95 /FV 20 ) were compared between anatomical and functional plans using the Wilcoxon signed ranks test. Results: Compared to anatomical IMRT plans, functional planning reduced FV 20 (median 2.7%, range 0.6-3.5%, p = 0.02), and total lung V 20 (median 1.5%, 0.5-2.7%, p = 0.02), with a small reduction in mean functional lung dose (median 0.4 Gy, 0-0.7 Gy, p = 0.03). There were no significant differences in target volume coverage or organ-at-risk doses. Plan quality index was improved for functional plans (median increase 1.4, range 0-11.8, p = 0.02). Conclusions: Statistically significant reductions in FV 20 , V 20 and mean functional lung dose are possible when IMRT planning is supplemented by functional information derived from SPECT or 3 He-MRI.

  17. An investigation into positron emission tomography contouring methods across two treatment planning systems

    International Nuclear Information System (INIS)

    Young, Tony; Som, Seu; Sathiakumar, Chithradevi; Holloway, Lois

    2013-01-01

    Positron emission tomography (PET) imaging has been used to provide additional information regarding patient tumor location, size, and staging for radiotherapy treatment planning purposes. This additional information reduces interobserver variability and produces more consistent contouring. It is well recognized that different contouring methodology for PET data results in different contoured volumes. The goal of this study was to compare the difference in PET contouring methods for 2 different treatment planning systems using a phantom dataset and a series of patient datasets. Contouring methodology was compared on the ADAC Pinnacle Treatment Planning System and the CMS XiO Treatment Planning System. Contours were completed on the phantom and patient datasets using a number of PET contouring methods—the standardized uptake value 2.5 method, 30%, 40%, and 50% of the maximum uptake method and the signal to background ratio method. Differences of >15% were observed for PET-contoured volumes between the different treatment planning systems for the same data and the same PET contouring methodology. Contoured volume differences between treatment planning systems were caused by differences in data formatting and display and the different contouring tools available. Differences in treatment planning system as well as contouring methodology should be considered carefully in dose-volume contouring and reporting, especially between centers that may use different treatment planning systems or those that have several different treatment planning systems

  18. SU-E-J-88: Margin Reduction of Level II/III Planning Target Volume for Image-Guided Simultaneous Integrated Boost Head-And-Neck Treatment

    International Nuclear Information System (INIS)

    Can, S; Neylon, J; Qi, S; Santhanam, A; Low, D

    2014-01-01

    Purpose: To investigate the feasibility of improved normal tissue sparing for head-and-neck (H'N) image-guided radiotherapy (IGRT) by employing tighter CTV-to-PTV margins for target level II/III though a GPU-based deformable image registration and dose accumulation framework. Methods: Ten H'N simultaneous integrated boost cases treated on TomoTherapy were retrospectively analyzed. Weekly kVCT scans in addition to daily MVCT scans were acquired for each patient. Reduced margin plans were generated with 0- mm margin for level II and III PTV (while 3-5 mm margin for PTV1) and compared with the standard margin plan using 3-5mm margin to all CTV1-3 (reference plan). An in-house developed GPU-based 3D image deformation tool was used to register and deform the weekly KVCTs with the planning CT and determine the delivered mean/minimum/maximum dose, dose volume histograms (DVHs), etc. Results: Compared with the reference plans, the averaged cord maximum, the right and left parotid doses reduced by 22.7 %, 16.5 %, and 9 % respectively in the reduced margin plans. The V95 for PTV2 and PTV3 were found within 2 and 5% between the reference and tighter margin plans. For the reduced margin plans, the averaged cumulative mean doses were consistent with the planned dose for PTV1, PTV2 and PTV3 within 1.5%, 1.7% and 1.4%. Similar dose variations of the delivered dose were seen for the reference and tighter margin plans. The delivered maximum and mean doses for the cord were 3.55 % and 2.37% higher than the planned doses; a 5 % higher cumulative mean dose for the parotids was also observed for the delivered dose than the planned doses in both plans. Conclusion: By imposing tighter CTV-to-PTV margins for level II and III targets for H'N irradiation, acceptable cumulative doses were achievable when coupled with weekly kVCT guidance while improving normal structure sparing

  19. Dosimetric Comparison of Real-Time MRI-Guided Tri-Cobalt-60 Versus Linear Accelerator-Based Stereotactic Body Radiation Therapy Lung Cancer Plans.

    Science.gov (United States)

    Wojcieszynski, Andrzej P; Hill, Patrick M; Rosenberg, Stephen A; Hullett, Craig R; Labby, Zacariah E; Paliwal, Bhudatt; Geurts, Mark W; Bayliss, R Adam; Bayouth, John E; Harari, Paul M; Bassetti, Michael F; Baschnagel, Andrew M

    2017-06-01

    Magnetic resonance imaging-guided radiation therapy has entered clinical practice at several major treatment centers. Treatment of early-stage non-small cell lung cancer with stereotactic body radiation therapy is one potential application of this modality, as some form of respiratory motion management is important to address. We hypothesize that magnetic resonance imaging-guided tri-cobalt-60 radiation therapy can be used to generate clinically acceptable stereotactic body radiation therapy treatment plans. Here, we report on a dosimetric comparison between magnetic resonance imaging-guided radiation therapy plans and internal target volume-based plans utilizing volumetric-modulated arc therapy. Ten patients with early-stage non-small cell lung cancer who underwent radiation therapy planning and treatment were studied. Following 4-dimensional computed tomography, patient images were used to generate clinically deliverable plans. For volumetric-modulated arc therapy plans, the planning tumor volume was defined as an internal target volume + 0.5 cm. For magnetic resonance imaging-guided plans, a single mid-inspiratory cycle was used to define a gross tumor volume, then expanded 0.3 cm to the planning tumor volume. Treatment plan parameters were compared. Planning tumor volumes trended larger for volumetric-modulated arc therapy-based plans, with a mean planning tumor volume of 47.4 mL versus 24.8 mL for magnetic resonance imaging-guided plans ( P = .08). Clinically acceptable plans were achievable via both methods, with bilateral lung V20, 3.9% versus 4.8% ( P = .62). The volume of chest wall receiving greater than 30 Gy was also similar, 22.1 versus 19.8 mL ( P = .78), as were all other parameters commonly used for lung stereotactic body radiation therapy. The ratio of the 50% isodose volume to planning tumor volume was lower in volumetric-modulated arc therapy plans, 4.19 versus 10.0 ( P guided tri-cobalt-60 radiation therapy is capable of delivering lung high

  20. Automated gamma knife radiosurgery treatment planning with image registration, data-mining, and Nelder-Mead simplex optimization

    International Nuclear Information System (INIS)

    Lee, Kuan J.; Barber, David C.; Walton, Lee

    2006-01-01

    Gamma knife treatments are usually planned manually, requiring much expertise and time. We describe a new, fully automatic method of treatment planning. The treatment volume to be planned is first compared with a database of past treatments to find volumes closely matching in size and shape. The treatment parameters of the closest matches are used as starting points for the new treatment plan. Further optimization is performed with the Nelder-Mead simplex method: the coordinates and weight of the isocenters are allowed to vary until a maximally conformal plan specific to the new treatment volume is found. The method was tested on a randomly selected set of 10 acoustic neuromas and 10 meningiomas. Typically, matching a new volume took under 30 seconds. The time for simplex optimization, on a 3 GHz Xeon processor, ranged from under a minute for small volumes ( 30 000 cubic mm,>20 isocenters). In 8/10 acoustic neuromas and 8/10 meningiomas, the automatic method found plans with conformation number equal or better than that of the manual plan. In 4/10 acoustic neuromas and 5/10 meningiomas, both overtreatment and undertreatment ratios were equal or better in automated plans. In conclusion, data-mining of past treatments can be used to derive starting parameters for treatment planning. These parameters can then be computer optimized to give good plans automatically