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Sample records for carlo treatment planning

  1. Monte Carlo Treatment Planning for Advanced Radiotherapy

    DEFF Research Database (Denmark)

    Cronholm, Rickard

    This Ph.d. project describes the development of a workflow for Monte Carlo Treatment Planning for clinical radiotherapy plans. The workflow may be utilized to perform an independent dose verification of treatment plans. Modern radiotherapy treatment delivery is often conducted by dynamically...... modulating the intensity of the field during the irradiation. The workflow described has the potential to fully model the dynamic delivery, including gantry rotation during irradiation, of modern radiotherapy. Three corner stones of Monte Carlo Treatment Planning are identified: Building, commissioning...

  2. DEVELOPMENT OF A MULTIMODAL MONTE CARLO BASED TREATMENT PLANNING SYSTEM.

    Science.gov (United States)

    Kumada, Hiroaki; Takada, Kenta; Sakurai, Yoshinori; Suzuki, Minoru; Takata, Takushi; Sakurai, Hideyuki; Matsumura, Akira; Sakae, Takeji

    2017-10-26

    To establish boron neutron capture therapy (BNCT), the University of Tsukuba is developing a treatment device and peripheral devices required in BNCT, such as a treatment planning system. We are developing a new multimodal Monte Carlo based treatment planning system (developing code: Tsukuba Plan). Tsukuba Plan allows for dose estimation in proton therapy, X-ray therapy and heavy ion therapy in addition to BNCT because the system employs PHITS as the Monte Carlo dose calculation engine. Regarding BNCT, several verifications of the system are being carried out for its practical usage. The verification results demonstrate that Tsukuba Plan allows for accurate estimation of thermal neutron flux and gamma-ray dose as fundamental radiations of dosimetry in BNCT. In addition to the practical use of Tsukuba Plan in BNCT, we are investigating its application to other radiation therapies. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Monte Carlo systems used for treatment planning and dose verification

    Energy Technology Data Exchange (ETDEWEB)

    Brualla, Lorenzo [Universitaetsklinikum Essen, NCTeam, Strahlenklinik, Essen (Germany); Rodriguez, Miguel [Centro Medico Paitilla, Balboa (Panama); Lallena, Antonio M. [Universidad de Granada, Departamento de Fisica Atomica, Molecular y Nuclear, Granada (Spain)

    2017-04-15

    General-purpose radiation transport Monte Carlo codes have been used for estimation of the absorbed dose distribution in external photon and electron beam radiotherapy patients since several decades. Results obtained with these codes are usually more accurate than those provided by treatment planning systems based on non-stochastic methods. Traditionally, absorbed dose computations based on general-purpose Monte Carlo codes have been used only for research, owing to the difficulties associated with setting up a simulation and the long computation time required. To take advantage of radiation transport Monte Carlo codes applied to routine clinical practice, researchers and private companies have developed treatment planning and dose verification systems that are partly or fully based on fast Monte Carlo algorithms. This review presents a comprehensive list of the currently existing Monte Carlo systems that can be used to calculate or verify an external photon and electron beam radiotherapy treatment plan. Particular attention is given to those systems that are distributed, either freely or commercially, and that do not require programming tasks from the end user. These systems are compared in terms of features and the simulation time required to compute a set of benchmark calculations. (orig.) [German] Seit mehreren Jahrzehnten werden allgemein anwendbare Monte-Carlo-Codes zur Simulation des Strahlungstransports benutzt, um die Verteilung der absorbierten Dosis in der perkutanen Strahlentherapie mit Photonen und Elektronen zu evaluieren. Die damit erzielten Ergebnisse sind meist akkurater als solche, die mit nichtstochastischen Methoden herkoemmlicher Bestrahlungsplanungssysteme erzielt werden koennen. Wegen des damit verbundenen Arbeitsaufwands und der langen Dauer der Berechnungen wurden Monte-Carlo-Simulationen von Dosisverteilungen in der konventionellen Strahlentherapie in der Vergangenheit im Wesentlichen in der Forschung eingesetzt. Im Bemuehen, Monte-Carlo

  4. 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

  5. Monte Carlo conformal treatment planning as an independent assessment

    International Nuclear Information System (INIS)

    Rincon, M.; Leal, A.; Perucha, M.; Carrasco, E.; Sanchez-Doblado, F.; Hospital Univ. Virgen Macarena, Sevilla; Arrans, R.; Sanchez-Calzado, J.A.; Errazquin, L.; Medrano, J.C.

    2001-01-01

    The wide range of possibilities available in Radiotherapy with conformal fields cannot be covered experimentally. For this reason, dosimetrical and planning procedures are based on approximate algorithms or systematic measurements. Dose distribution calculations based on Monte Carlo (MC) simulations can be used to check results. In this work, two examples of conformal field treatments are shown: A prostate carcinoma and an ocular lymphoma. The dose distributions obtained with a conventional Planning System and with MC have been compared. Some significant differences have been found. (orig.)

  6. Treatment planning in radiosurgery: parallel Monte Carlo simulation software

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, G. [Galliera Hospitals, Genova (Italy). Dept. of Hospital Physics; Grillo Ruggieri, F. [Galliera Hospitals, Genova (Italy) Dept. for Radiation Therapy; Modesti, M.; Felici, R. [Electronic Data System, Rome (Italy); Surridge, M. [University of South Hampton (United Kingdom). Parallel Apllication Centre

    1995-12-01

    The main objective of this research was to evaluate the possibility of direct Monte Carlo simulation for accurate dosimetry with short computation time. We made us of: graphics workstation, linear accelerator, water, PMMA and anthropomorphic phantoms, for validation purposes; ionometric, film and thermo-luminescent techniques, for dosimetry; treatment planning system for comparison. Benchmarking results suggest that short computing times can be obtained with use of the parallel version of EGS4 that was developed. Parallelism was obtained assigning simulation incident photons to separate processors, and the development of a parallel random number generator was necessary. Validation consisted in: phantom irradiation, comparison of predicted and measured values good agreement in PDD and dose profiles. Experiments on anthropomorphic phantoms (with inhomogeneities) were carried out, and these values are being compared with results obtained with the conventional treatment planning system.

  7. Efficient sampling algorithms for Monte Carlo based treatment planning

    International Nuclear Information System (INIS)

    DeMarco, J.J.; Solberg, T.D.; Chetty, I.; Smathers, J.B.

    1998-01-01

    Efficient sampling algorithms are necessary for producing a fast Monte Carlo based treatment planning code. This study evaluates several aspects of a photon-based tracking scheme and the effect of optimal sampling algorithms on the efficiency of the code. Four areas were tested: pseudo-random number generation, generalized sampling of a discrete distribution, sampling from the exponential distribution, and delta scattering as applied to photon transport through a heterogeneous simulation geometry. Generalized sampling of a discrete distribution using the cutpoint method can produce speedup gains of one order of magnitude versus conventional sequential sampling. Photon transport modifications based upon the delta scattering method were implemented and compared with a conventional boundary and collision checking algorithm. The delta scattering algorithm is faster by a factor of six versus the conventional algorithm for a boundary size of 5 mm within a heterogeneous geometry. A comparison of portable pseudo-random number algorithms and exponential sampling techniques is also discussed

  8. Vega library for processing DICOM data required in Monte Carlo verification of radiotherapy treatment plans

    International Nuclear Information System (INIS)

    Locke, C.; Zavgorodni, S.; British Columbia Cancer Agency, Vancouver Island Center, Victoria BC

    2008-01-01

    Monte Carlo (MC) methods provide the most accurate to-date dose calculations in heterogeneous media and complex geometries, and this spawns increasing interest in incorporating MC calculations into treatment planning quality assurance process. This involves MC dose calculations for clinically produced treatment plans. To perform these calculations, a number of treatment plan parameters specifying radiation beam

  9. Monte Carlo treatment planning with modulated electron radiotherapy: framework development and application

    Science.gov (United States)

    Alexander, Andrew William

    Within the field of medical physics, Monte Carlo radiation transport simulations are considered to be the most accurate method for the determination of dose distributions in patients. The McGill Monte Carlo treatment planning system (MMCTP), provides a flexible software environment to integrate Monte Carlo simulations with current and new treatment modalities. A developing treatment modality called energy and intensity modulated electron radiotherapy (MERT) is a promising modality, which has the fundamental capabilities to enhance the dosimetry of superficial targets. An objective of this work is to advance the research and development of MERT with the end goal of clinical use. To this end, we present the MMCTP system with an integrated toolkit for MERT planning and delivery of MERT fields. Delivery is achieved using an automated "few leaf electron collimator" (FLEC) and a controller. Aside from the MERT planning toolkit, the MMCTP system required numerous add-ons to perform the complex task of large-scale autonomous Monte Carlo simulations. The first was a DICOM import filter, followed by the implementation of DOSXYZnrc as a dose calculation engine and by logic methods for submitting and updating the status of Monte Carlo simulations. Within this work we validated the MMCTP system with a head and neck Monte Carlo recalculation study performed by a medical dosimetrist. The impact of MMCTP lies in the fact that it allows for systematic and platform independent large-scale Monte Carlo dose calculations for different treatment sites and treatment modalities. In addition to the MERT planning tools, various optimization algorithms were created external to MMCTP. The algorithms produced MERT treatment plans based on dose volume constraints that employ Monte Carlo pre-generated patient-specific kernels. The Monte Carlo kernels are generated from patient-specific Monte Carlo dose distributions within MMCTP. The structure of the MERT planning toolkit software and

  10. Clinical treatment planning for stereotactic radiotherapy, evaluation by Monte Carlo simulation

    International Nuclear Information System (INIS)

    Kairn, T.; Aland, T.; Kenny, J.; Knight, R.T.; Crowe, S.B.; Langton, C.M.; Franich, R.D.; Johnston, P.N.

    2010-01-01

    Full text: This study uses re-evaluates the doses delivered by a series of clinical stereotactic radiotherapy treatments, to test the accuracy of treatment planning predictions for very small radiation fields. Stereotactic radiotherapy treatment plans for meningiomas near the petrous temporal bone and the foramen magnum (incorp rating fields smaller than I c m2) were examined using Monte Carlo simulations. Important differences between treatment planning predictions and Monte Carlo calculations of doses delivered to stereotactic radiotherapy patients are apparent. For example, in one case the Monte Carlo calculation shows that the delivery a planned meningioma treatment would spare the patient's critical structures (eyes, brainstem) more effectively than the treatment plan predicted, and therefore suggests that this patient could safely receive an increased dose to their tumour. Monte Carlo simulations can be used to test the dose predictions made by a conventional treatment planning system, for dosimetrically challenging small fields, and can thereby suggest valuable modifications to clinical treatment plans. This research was funded by the Wesley Research Institute, Australia. The authors wish to thank Andrew Fielding and David Schlect for valuable discussions of aspects of this work. The authors are also grateful to Muhammad Kakakhel, for assisting with the design and calibration of our linear accelerator model, and to the stereotactic radiation therapy team at Premion, who designed the treatment plans. Computational resources and services used in this work were provided by the HPC and Research Support Unit, QUT, Brisbane, Australia. (author)

  11. Application of OMEGA Monte Carlo codes for radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Ayyangar, Komanduri M.; Jiang, Steve B.

    1998-01-01

    The accuracy of conventional dose algorithms for radiosurgery treatment planning is limited, due to the inadequate consideration of the lateral radiation transport and the difficulty of acquiring accurate dosimetric data for very small beams. In the present paper, some initial work on the application of Monte Carlo method in radiation treatment planning in general, and in radiosurgery treatment planning in particular, has been presented. Two OMEGA Monte Carlo codes, BEAM and DOSXYZ, are used. The BEAM code is used to simulate the transport of particles in the linac treatment head and radiosurgery collimator. A phase space file is obtained from the BEAM simulation for each collimator size. The DOSXYZ code is used to calculate the dose distribution in the patient's body reconstructed from CT slices using the phase space file as input. The accuracy of OMEGA Monte Carlo simulation for radiosurgery dose calculation is verified by comparing the calculated and measured basic dosimetric data for several radiosurgery beams and a 4 x 4 cm 2 conventional beam. The dose distributions for three clinical cases are calculated using OMEGA codes as the dose engine for an in-house developed radiosurgery treatment planning system. The verification using basic dosimetric data and the dose calculation for clinical cases demonstrate the feasibility of applying OMEGA Monte Carlo code system to radiosurgery treatment planning. (author)

  12. IMRT head and neck treatment planning with a commercially available Monte Carlo based planning system

    International Nuclear Information System (INIS)

    Boudreau, C; Heath, E; Seuntjens, J; Ballivy, O; Parker, W

    2005-01-01

    The PEREGRINE Monte Carlo dose-calculation system (North American Scientific, Cranberry Township, PA) is the first commercially available Monte Carlo dose-calculation code intended specifically for intensity modulated radiotherapy (IMRT) treatment planning and quality assurance. In order to assess the impact of Monte Carlo based dose calculations for IMRT clinical cases, dose distributions for 11 head and neck patients were evaluated using both PEREGRINE and the CORVUS (North American Scientific, Cranberry Township, PA) finite size pencil beam (FSPB) algorithm with equivalent path-length (EPL) inhomogeneity correction. For the target volumes, PEREGRINE calculations predict, on average, a less than 2% difference in the calculated mean and maximum doses to the gross tumour volume (GTV) and clinical target volume (CTV). An average 16% ± 4% and 12% ± 2% reduction in the volume covered by the prescription isodose line was observed for the GTV and CTV, respectively. Overall, no significant differences were noted in the doses to the mandible and spinal cord. For the parotid glands, PEREGRINE predicted a 6% ± 1% increase in the volume of tissue receiving a dose greater than 25 Gy and an increase of 4% ± 1% in the mean dose. Similar results were noted for the brainstem where PEREGRINE predicted a 6% ± 2% increase in the mean dose. The observed differences between the PEREGRINE and CORVUS calculated dose distributions are attributed to secondary electron fluence perturbations, which are not modelled by the EPL correction, issues of organ outlining, particularly in the vicinity of air cavities, and differences in dose reporting (dose to water versus dose to tissue type)

  13. MMCTP: a radiotherapy research environment for Monte Carlo and patient-specific treatment planning

    International Nuclear Information System (INIS)

    Alexander, A; DeBlois, F; Stroian, G; Al-Yahya, K; Heath, E; Seuntjens, J

    2007-01-01

    Radiotherapy research lacks a flexible computational research environment for Monte Carlo (MC) and patient-specific treatment planning. The purpose of this study was to develop a flexible software package on low-cost hardware with the aim of integrating new patient-specific treatment planning with MC dose calculations suitable for large-scale prospective and retrospective treatment planning studies. We designed the software package 'McGill Monte Carlo treatment planning' (MMCTP) for the research development of MC and patient-specific treatment planning. The MMCTP design consists of a graphical user interface (GUI), which runs on a simple workstation connected through standard secure-shell protocol to a cluster for lengthy MC calculations. Treatment planning information (e.g., images, structures, beam geometry properties and dose distributions) is converted into a convenient MMCTP local file storage format designated, the McGill RT format. MMCTP features include (a) DICOM R T, RTOG and CADPlan CART format imports; (b) 2D and 3D visualization views for images, structure contours, and dose distributions; (c) contouring tools; (d) DVH analysis, and dose matrix comparison tools; (e) external beam editing; (f) MC transport calculation from beam source to patient geometry for photon and electron beams. The MC input files, which are prepared from the beam geometry properties and patient information (e.g., images and structure contours), are uploaded and run on a cluster using shell commands controlled from the MMCTP GUI. The visualization, dose matrix operation and DVH tools offer extensive options for plan analysis and comparison between MC plans and plans imported from commercial treatment planning systems. The MMCTP GUI provides a flexible research platform for the development of patient-specific MC treatment planning for photon and electron external beam radiation therapy. The impact of this tool lies in the fact that it allows for systematic, platform

  14. Monte Carlo based dosimetry and treatment planning for neutron capture therapy of brain tumors

    International Nuclear Information System (INIS)

    Zamenhof, R.G.; Clement, S.D.; Harling, O.K.; Brenner, J.F.; Wazer, D.E.; Madoc-Jones, H.; Yanch, J.C.

    1990-01-01

    Monte Carlo based dosimetry and computer-aided treatment planning for neutron capture therapy have been developed to provide the necessary link between physical dosimetric measurements performed on the MITR-II epithermal-neutron beams and the need of the radiation oncologist to synthesize large amounts of dosimetric data into a clinically meaningful treatment plan for each individual patient. Monte Carlo simulation has been employed to characterize the spatial dose distributions within a skull/brain model irradiated by an epithermal-neutron beam designed for neutron capture therapy applications. The geometry and elemental composition employed for the mathematical skull/brain model and the neutron and photon fluence-to-dose conversion formalism are presented. A treatment planning program, NCTPLAN, developed specifically for neutron capture therapy, is described. Examples are presented illustrating both one and two-dimensional dose distributions obtainable within the brain with an experimental epithermal-neutron beam, together with beam quality and treatment plan efficacy criteria which have been formulated for neutron capture therapy. The incorporation of three-dimensional computed tomographic image data into the treatment planning procedure is illustrated. The experimental epithermal-neutron beam has a maximum usable circular diameter of 20 cm, and with 30 ppm of B-10 in tumor and 3 ppm of B-10 in blood, it produces a beam-axis advantage depth of 7.4 cm, a beam-axis advantage ratio of 1.83, a global advantage ratio of 1.70, and an advantage depth RBE-dose rate to tumor of 20.6 RBE-cGy/min (cJ/kg-min). These characteristics make this beam well suited for clinical applications, enabling an RBE-dose of 2,000 RBE-cGy/min (cJ/kg-min) to be delivered to tumor at brain midline in six fractions with a treatment time of approximately 16 minutes per fraction

  15. Monte Carlo evaluation of a photon pencil kernel algorithm applied to fast neutron therapy treatment planning

    Science.gov (United States)

    Söderberg, Jonas; Alm Carlsson, Gudrun; Ahnesjö, Anders

    2003-10-01

    When dedicated software is lacking, treatment planning for fast neutron therapy is sometimes performed using dose calculation algorithms designed for photon beam therapy. In this work Monte Carlo derived neutron pencil kernels in water were parametrized using the photon dose algorithm implemented in the Nucletron TMS (treatment management system) treatment planning system. A rectangular fast-neutron fluence spectrum with energies 0-40 MeV (resembling a polyethylene filtered p(41)+ Be spectrum) was used. Central axis depth doses and lateral dose distributions were calculated and compared with the corresponding dose distributions from Monte Carlo calculations for homogeneous water and heterogeneous slab phantoms. All absorbed doses were normalized to the reference dose at 10 cm depth for a field of radius 5.6 cm in a 30 × 40 × 20 cm3 water test phantom. Agreement to within 7% was found in both the lateral and the depth dose distributions. The deviations could be explained as due to differences in size between the test phantom and that used in deriving the pencil kernel (radius 200 cm, thickness 50 cm). In the heterogeneous phantom, the TMS, with a directly applied neutron pencil kernel, and Monte Carlo calculated absorbed doses agree approximately for muscle but show large deviations for media such as adipose or bone. For the latter media, agreement was substantially improved by correcting the absorbed doses calculated in TMS with the neutron kerma factor ratio and the stopping power ratio between tissue and water. The multipurpose Monte Carlo code FLUKA was used both in calculating the pencil kernel and in direct calculations of absorbed dose in the phantom.

  16. A Monte Carlo-based treatment-planning tool for ion beam therapy

    CERN Document Server

    Böhlen, T T; Dosanjh, M; Ferrari, A; Haberer, T; Parodi, K; Patera, V; Mairan, A

    2013-01-01

    Ion beam therapy, as an emerging radiation therapy modality, requires continuous efforts to develop and improve tools for patient treatment planning (TP) and research applications. Dose and fluence computation algorithms using the Monte Carlo (MC) technique have served for decades as reference tools for accurate dose computations for radiotherapy. In this work, a novel MC-based treatment-planning (MCTP) tool for ion beam therapy using the pencil beam scanning technique is presented. It allows single-field and simultaneous multiple-fields optimization for realistic patient treatment conditions and for dosimetric quality assurance for irradiation conditions at state-of-the-art ion beam therapy facilities. It employs iterative procedures that allow for the optimization of absorbed dose and relative biological effectiveness (RBE)-weighted dose using radiobiological input tables generated by external RBE models. Using a re-implementation of the local effect model (LEM), theMCTP tool is able to perform TP studies u...

  17. EDITORIAL: International Workshop on Current Topics in Monte Carlo Treatment Planning

    Science.gov (United States)

    Verhaegen, Frank; Seuntjens, Jan

    2005-03-01

    The use of Monte Carlo particle transport simulations in radiotherapy was pioneered in the early nineteen-seventies, but it was not until the eighties that they gained recognition as an essential research tool for radiation dosimetry, health physics and later on for radiation therapy treatment planning. Since the mid-nineties, there has been a boom in the number of workers using MC techniques in radiotherapy, and the quantity of papers published on the subject. Research and applications of MC techniques in radiotherapy span a very wide range from fundamental studies of cross sections and development of particle transport algorithms, to clinical evaluation of treatment plans for a variety of radiotherapy modalities. The International Workshop on Current Topics in Monte Carlo Treatment Planning took place at Montreal General Hospital, which is part of McGill University, halfway up Mount Royal on Montreal Island. It was held from 3-5 May, 2004, right after the freezing winter has lost its grip on Canada. About 120 workers attended the Workshop, representing 18 countries. Most of the pioneers in the field were present but also a large group of young scientists. In a very full programme, 41 long papers were presented (of which 12 were invited) and 20 posters were on display during the whole meeting. The topics covered included the latest developments in MC algorithms, statistical issues, source modelling and MC treatment planning for photon, electron and proton treatments. The final day was entirely devoted to clinical implementation issues. Monte Carlo radiotherapy treatment planning has only now made a slow entrée in the clinical environment, taking considerably longer than envisaged ten years ago. Of the twenty-five papers in this dedicated special issue, about a quarter deal with this topic, with probably many more studies to follow in the near future. If anything, we hope the Workshop served as an accelerator for more clinical evaluation of MC applications. The

  18. An Approach in Radiation Therapy Treatment Planning: A Fast, GPU-Based Monte Carlo Method.

    Science.gov (United States)

    Karbalaee, Mojtaba; Shahbazi-Gahrouei, Daryoush; Tavakoli, Mohammad B

    2017-01-01

    An accurate and fast radiation dose calculation is essential for successful radiation radiotherapy. The aim of this study was to implement a new graphic processing unit (GPU) based radiation therapy treatment planning for accurate and fast dose calculation in radiotherapy centers. A program was written for parallel running based on GPU. The code validation was performed by EGSnrc/DOSXYZnrc. Moreover, a semi-automatic, rotary, asymmetric phantom was designed and produced using a bone, the lung, and the soft tissue equivalent materials. All measurements were performed using a Mapcheck dosimeter. The accuracy of the code was validated using the experimental data, which was obtained from the anthropomorphic phantom as the gold standard. The findings showed that, compared with those of DOSXYZnrc in the virtual phantom and for most of the voxels (>95%), GPU-based Monte Carlo method in dose calculation may be useful in routine radiation therapy centers as the core and main component of a treatment planning verification system.

  19. Implementation of random set-up errors in Monte Carlo calculated dynamic IMRT treatment plans

    International Nuclear Information System (INIS)

    Stapleton, S; Zavgorodni, S; Popescu, I A; Beckham, W A

    2005-01-01

    The fluence-convolution method for incorporating random set-up errors (RSE) into the Monte Carlo treatment planning dose calculations was previously proposed by Beckham et al, and it was validated for open field radiotherapy treatments. This study confirms the applicability of the fluence-convolution method for dynamic intensity modulated radiotherapy (IMRT) dose calculations and evaluates the impact of set-up uncertainties on a clinical IMRT dose distribution. BEAMnrc and DOSXYZnrc codes were used for Monte Carlo calculations. A sliding window IMRT delivery was simulated using a dynamic multi-leaf collimator (DMLC) transport model developed by Keall et al. The dose distributions were benchmarked for dynamic IMRT fields using extended dose range (EDR) film, accumulating the dose from 16 subsequent fractions shifted randomly. Agreement of calculated and measured relative dose values was well within statistical uncertainty. A clinical seven field sliding window IMRT head and neck treatment was then simulated and the effects of random set-up errors (standard deviation of 2 mm) were evaluated. The dose-volume histograms calculated in the PTV with and without corrections for RSE showed only small differences indicating a reduction of the volume of high dose region due to set-up errors. As well, it showed that adequate coverage of the PTV was maintained when RSE was incorporated. Slice-by-slice comparison of the dose distributions revealed differences of up to 5.6%. The incorporation of set-up errors altered the position of the hot spot in the plan. This work demonstrated validity of implementation of the fluence-convolution method to dynamic IMRT Monte Carlo dose calculations. It also showed that accounting for the set-up errors could be essential for correct identification of the value and position of the hot spot

  20. Implementation of random set-up errors in Monte Carlo calculated dynamic IMRT treatment plans

    Science.gov (United States)

    Stapleton, S.; Zavgorodni, S.; Popescu, I. A.; Beckham, W. A.

    2005-02-01

    The fluence-convolution method for incorporating random set-up errors (RSE) into the Monte Carlo treatment planning dose calculations was previously proposed by Beckham et al, and it was validated for open field radiotherapy treatments. This study confirms the applicability of the fluence-convolution method for dynamic intensity modulated radiotherapy (IMRT) dose calculations and evaluates the impact of set-up uncertainties on a clinical IMRT dose distribution. BEAMnrc and DOSXYZnrc codes were used for Monte Carlo calculations. A sliding window IMRT delivery was simulated using a dynamic multi-leaf collimator (DMLC) transport model developed by Keall et al. The dose distributions were benchmarked for dynamic IMRT fields using extended dose range (EDR) film, accumulating the dose from 16 subsequent fractions shifted randomly. Agreement of calculated and measured relative dose values was well within statistical uncertainty. A clinical seven field sliding window IMRT head and neck treatment was then simulated and the effects of random set-up errors (standard deviation of 2 mm) were evaluated. The dose-volume histograms calculated in the PTV with and without corrections for RSE showed only small differences indicating a reduction of the volume of high dose region due to set-up errors. As well, it showed that adequate coverage of the PTV was maintained when RSE was incorporated. Slice-by-slice comparison of the dose distributions revealed differences of up to 5.6%. The incorporation of set-up errors altered the position of the hot spot in the plan. This work demonstrated validity of implementation of the fluence-convolution method to dynamic IMRT Monte Carlo dose calculations. It also showed that accounting for the set-up errors could be essential for correct identification of the value and position of the hot spot.

  1. Monte Carlo based treatment planning systems for Boron Neutron Capture Therapy in Petten, The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Nievaart, V A; Daquino, G G; Moss, R L [JRC European Commission, PO Box 2, 1755ZG Petten (Netherlands)

    2007-06-15

    Boron Neutron Capture Therapy (BNCT) is a bimodal form of radiotherapy for the treatment of tumour lesions. Since the cancer cells in the treatment volume are targeted with {sup 10}B, a higher dose is given to these cancer cells due to the {sup 10}B(n,{alpha}){sup 7}Li reaction, in comparison with the surrounding healthy cells. In Petten (The Netherlands), at the High Flux Reactor, a specially tailored neutron beam has been designed and installed. Over 30 patients have been treated with BNCT in 2 clinical protocols: a phase I study for the treatment of glioblastoma multiforme and a phase II study on the treatment of malignant melanoma. Furthermore, activities concerning the extra-corporal treatment of metastasis in the liver (from colorectal cancer) are in progress. The irradiation beam at the HFR contains both neutrons and gammas that, together with the complex geometries of both patient and beam set-up, demands for very detailed treatment planning calculations. A well designed Treatment Planning System (TPS) should obey the following general scheme: (1) a pre-processing phase (CT and/or MRI scans to create the geometric solid model, cross-section files for neutrons and/or gammas); (2) calculations (3D radiation transport, estimation of neutron and gamma fluences, macroscopic and microscopic dose); (3) post-processing phase (displaying of the results, iso-doses and -fluences). Treatment planning in BNCT is performed making use of Monte Carlo codes incorporated in a framework, which includes also the pre- and post-processing phases. In particular, the glioblastoma multiforme protocol used BNCT{sub r}tpe, while the melanoma metastases protocol uses NCTPlan. In addition, an ad hoc Positron Emission Tomography (PET) based treatment planning system (BDTPS) has been implemented in order to integrate the real macroscopic boron distribution obtained from PET scanning. BDTPS is patented and uses MCNP as the calculation engine. The precision obtained by the Monte Carlo

  2. Monte Carlo fluence simulation for prospective evaluation of interstitial photodynamic therapy treatment plans

    Science.gov (United States)

    Cassidy, Jeffrey; Betz, Vaughn; Lilge, Lothar

    2015-03-01

    Photodynamic therapy (PDT) delivers a localized cytotoxic dose that is a function of tissue oxygen availability, photosensitive drug concentration, and light fluence. Providing safe and effective PDT requires an understanding of all three elements and the physiological response to the radicals generated. Interstitial PDT (IPDT) for solid tumours poses particular challenges due to complex organ geometries and the associated limitations for diffusion theory based fluence rate prediction, in addition to restricted access for light delivery and dose monitoring. As a first step towards enabling a complete prospective IPDT treatment-planning platform, we demonstrate use of our previously developed FullMonte tetrahedral Monte Carlo simulation engine for modeling of the interstitial fluence field due to intravesicular insertion of brief light sources. The goal is to enable a complete treatment planning and monitoring work flow analogous to that used in ionizing radiation therapy, including plan evaluation through dose-volume histograms and algorithmic treatment plan optimization. FullMonte is to our knowledge the fastest open-source tetrahedral MC light propagation software. Using custom hardware acceleration, we achieve 4x faster computing with 67x better power efficiency for limited-size meshes compared to the software. Ongoing work will improve the performance advantage to 16x with unlimited mesh size, enabling algorithmic plan optimization in reasonable time. Using FullMonte, we demonstrate significant new plan-evaluation capabilities including fluence field visualization, generation of organ dose-volume histograms, and rendering of isofluence surfaces for a representative bladder cancer mesh from a real patient. We also discuss the advantages of MC simulations for dose-volume histogram generation and the need for online personalized fluence-rate monitoring.

  3. A fast - Monte Carlo toolkit on GPU for treatment plan dose recalculation in proton therapy

    Science.gov (United States)

    Senzacqua, M.; Schiavi, A.; Patera, V.; Pioli, S.; Battistoni, G.; Ciocca, M.; Mairani, A.; Magro, G.; Molinelli, S.

    2017-10-01

    In the context of the particle therapy a crucial role is played by Treatment Planning Systems (TPSs), tools aimed to compute and optimize the tratment plan. Nowadays one of the major issues related to the TPS in particle therapy is the large CPU time needed. We developed a software toolkit (FRED) for reducing dose recalculation time by exploiting Graphics Processing Units (GPU) hardware. Thanks to their high parallelization capability, GPUs significantly reduce the computation time, up to factor 100 respect to a standard CPU running software. The transport of proton beams in the patient is accurately described through Monte Carlo methods. Physical processes reproduced are: Multiple Coulomb Scattering, energy straggling and nuclear interactions of protons with the main nuclei composing the biological tissues. FRED toolkit does not rely on the water equivalent translation of tissues, but exploits the Computed Tomography anatomical information by reconstructing and simulating the atomic composition of each crossed tissue. FRED can be used as an efficient tool for dose recalculation, on the day of the treatment. In fact it can provide in about one minute on standard hardware the dose map obtained combining the treatment plan, earlier computed by the TPS, and the current patient anatomic arrangement.

  4. CT-Based Brachytherapy Treatment Planning using Monte Carlo Simulation Aided by an Interface Software

    Directory of Open Access Journals (Sweden)

    Vahid Moslemi

    2011-03-01

    Full Text Available Introduction: In brachytherapy, radioactive sources are placed close to the tumor, therefore, small changes in their positions can cause large changes in the dose distribution. This emphasizes the need for computerized treatment planning. The usual method for treatment planning of cervix brachytherapy uses conventional radiographs in the Manchester system. Nowadays, because of their advantages in locating the source positions and the surrounding tissues, CT and MRI images are replacing conventional radiographs. In this study, we used CT images in Monte Carlo based dose calculation for brachytherapy treatment planning, using an interface software to create the geometry file required in the MCNP code. The aim of using the interface software is to facilitate and speed up the geometry set-up for simulations based on the patient’s anatomy. This paper examines the feasibility of this method in cervix brachytherapy and assesses its accuracy and speed. Material and Methods: For dosimetric measurements regarding the treatment plan, a pelvic phantom was made from polyethylene in which the treatment applicators could be placed. For simulations using CT images, the phantom was scanned at 120 kVp. Using an interface software written in MATLAB, the CT images were converted into MCNP input file and the simulation was then performed. Results: Using the interface software, preparation time for the simulations of the applicator and surrounding structures was approximately 3 minutes; the corresponding time needed in the conventional MCNP geometry entry being approximately 1 hour. The discrepancy in the simulated and measured doses to point A was 1.7% of the prescribed dose.  The corresponding dose differences between the two methods in rectum and bladder were 3.0% and 3.7% of the prescribed dose, respectively. Comparing the results of simulation using the interface software with those of simulation using the standard MCNP geometry entry showed a less than 1

  5. Reporting and analyzing statistical uncertainties in Monte Carlo-based treatment planning

    International Nuclear Information System (INIS)

    Chetty, Indrin J.; Rosu, Mihaela; Kessler, Marc L.; Fraass, Benedick A.; Haken, Randall K. ten; Kong, Feng-Ming; McShan, Daniel L.

    2006-01-01

    Purpose: To investigate methods of reporting and analyzing statistical uncertainties in doses to targets and normal tissues in Monte Carlo (MC)-based treatment planning. Methods and Materials: Methods for quantifying statistical uncertainties in dose, such as uncertainty specification to specific dose points, or to volume-based regions, were analyzed in MC-based treatment planning for 5 lung cancer patients. The effect of statistical uncertainties on target and normal tissue dose indices was evaluated. The concept of uncertainty volume histograms for targets and organs at risk was examined, along with its utility, in conjunction with dose volume histograms, in assessing the acceptability of the statistical precision in dose distributions. The uncertainty evaluation tools were extended to four-dimensional planning for application on multiple instances of the patient geometry. All calculations were performed using the Dose Planning Method MC code. Results: For targets, generalized equivalent uniform doses and mean target doses converged at 150 million simulated histories, corresponding to relative uncertainties of less than 2% in the mean target doses. For the normal lung tissue (a volume-effect organ), mean lung dose and normal tissue complication probability converged at 150 million histories despite the large range in the relative organ uncertainty volume histograms. For 'serial' normal tissues such as the spinal cord, large fluctuations exist in point dose relative uncertainties. Conclusions: The tools presented here provide useful means for evaluating statistical precision in MC-based dose distributions. Tradeoffs between uncertainties in doses to targets, volume-effect organs, and 'serial' normal tissues must be considered carefully in determining acceptable levels of statistical precision in MC-computed dose distributions

  6. A new Monte Carlo-based treatment plan optimization approach for intensity modulated radiation therapy.

    Science.gov (United States)

    Li, Yongbao; Tian, Zhen; Shi, Feng; Song, Ting; Wu, Zhaoxia; Liu, Yaqiang; Jiang, Steve; Jia, Xun

    2015-04-07

    Intensity-modulated radiation treatment (IMRT) plan optimization needs beamlet dose distributions. Pencil-beam or superposition/convolution type algorithms are typically used because of their high computational speed. However, inaccurate beamlet dose distributions may mislead the optimization process and hinder the resulting plan quality. To solve this problem, the Monte Carlo (MC) simulation method has been used to compute all beamlet doses prior to the optimization step. The conventional approach samples the same number of particles from each beamlet. Yet this is not the optimal use of MC in this problem. In fact, there are beamlets that have very small intensities after solving the plan optimization problem. For those beamlets, it may be possible to use fewer particles in dose calculations to increase efficiency. Based on this idea, we have developed a new MC-based IMRT plan optimization framework that iteratively performs MC dose calculation and plan optimization. At each dose calculation step, the particle numbers for beamlets were adjusted based on the beamlet intensities obtained through solving the plan optimization problem in the last iteration step. We modified a GPU-based MC dose engine to allow simultaneous computations of a large number of beamlet doses. To test the accuracy of our modified dose engine, we compared the dose from a broad beam and the summed beamlet doses in this beam in an inhomogeneous phantom. Agreement within 1% for the maximum difference and 0.55% for the average difference was observed. We then validated the proposed MC-based optimization schemes in one lung IMRT case. It was found that the conventional scheme required 10(6) particles from each beamlet to achieve an optimization result that was 3% difference in fluence map and 1% difference in dose from the ground truth. In contrast, the proposed scheme achieved the same level of accuracy with on average 1.2 × 10(5) particles per beamlet. Correspondingly, the computation

  7. Dosimetric evaluation of a Monte Carlo IMRT treatment planning system incorporating the MIMiC

    International Nuclear Information System (INIS)

    Rassiah-Szegedi, P; Fuss, M; Sheikh-Bagheri, D; Szegedi, M; Stathakis, S; Lancaster, J; Papanikolaou, N; Salter, B

    2007-01-01

    The high dose per fraction delivered to lung lesions in stereotactic body radiation therapy (SBRT) demands high dose calculation and delivery accuracy. The inhomogeneous density in the thoracic region along with the small fields used typically in intensity-modulated radiation therapy (IMRT) treatments poses a challenge in the accuracy of dose calculation. In this study we dosimetrically evaluated a pre-release version of a Monte Carlo planning system (PEREGRINE 1.6b, NOMOS Corp., Cranberry Township, PA), which incorporates the modeling of serial tomotherapy IMRT treatments with the binary multileaf intensity modulating collimator (MIMiC). The aim of this study is to show the validation process of PEREGRINE 1.6b since it was used as a benchmark to investigate the accuracy of doses calculated by a finite size pencil beam (FSPB) algorithm for lung lesions treated on the SBRT dose regime via serial tomotherapy in our previous study. Doses calculated by PEREGRINE were compared against measurements in homogeneous and inhomogeneous materials carried out on a Varian 600C with a 6 MV photon beam. Phantom studies simulating various sized lesions were also carried out to explain some of the large dose discrepancies seen in the dose calculations with small lesions. Doses calculated by PEREGRINE agreed to within 2% in water and up to 3% for measurements in an inhomogeneous phantom containing lung, bone and unit density tissue

  8. Status of Monte Carlo dose planning

    International Nuclear Information System (INIS)

    Mackie, T.R.

    1995-01-01

    Monte Carlo simulation will become increasing important for treatment planning for radiotherapy. The EGS4 Monte Carlo system, a general particle transport system, has been used most often for simulation tasks in radiotherapy although ETRAN/ITS and MCNP have also been used. Monte Carlo treatment planning requires that the beam characteristics such as the energy spectrum and angular distribution of particles emerging from clinical accelerators be accurately represented. An EGS4 Monte Carlo code, called BEAM, was developed by the OMEGA Project (a collaboration between the University of Wisconsin and the National Research Council of Canada) to transport particles through linear accelerator heads. This information was used as input to simulate the passage of particles through CT-based representations of phantoms or patients using both an EGS4 code (DOSXYZ) and the macro Monte Carlo (MMC) method. Monte Carlo computed 3-D electron beam dose distributions compare well to measurements obtained in simple and complex heterogeneous phantoms. The present drawback with most Monte Carlo codes is that simulation times are slower than most non-stochastic dose computation algorithms. This is especially true for photon dose planning. In the future dedicated Monte Carlo treatment planning systems like Peregrine (from Lawrence Livermore National Laboratory), which will be capable of computing the dose from all beam types, or the Macro Monte Carlo (MMC) system, which is an order of magnitude faster than other algorithms, may dominate the field

  9. Commissioning of a Monte Carlo treatment planning system for clinical use in radiation therapy; Evaluacion de un sistema de planificacion Monte Carlo de uso clinico para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Zucca Aparcio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrila, J.

    2016-10-01

    The commissioning procedures of a Monte Carlo treatment planning system (MC) for photon beams from a dedicated stereotactic body radiosurgery (SBRT) unit has been reported in this document. XVMC has been the MC Code available in the treatment planning system evaluated (BrainLAB iPlan RT Dose) which is based on Virtual Source Models that simulate the primary and scattered radiation, besides the electronic contamination, using gaussian components for whose modelling are required measurements of dose profiles, percentage depth dose and output factors, performed both in water and in air. The dosimetric accuracy of the particle transport simulation has been analyzed by validating the calculations in homogeneous and heterogeneous media versus measurements made under the same conditions as the dose calculation, and checking the stochastic behaviour of Monte Carlo calculations when using different statistical variances. Likewise, it has been verified how the planning system performs the conversion from dose to medium to dose to water, applying the stopping power ratio water to medium, in the presence of heterogeneities where this phenomenon is relevant, such as high density media (cortical bone). (Author)

  10. EDITORIAL: Special section: Selected papers from the Second European Workshop on Monte Carlo Treatment Planning (MCTP2009) Special section: Selected papers from the Second European Workshop on Monte Carlo Treatment Planning (MCTP2009)

    Science.gov (United States)

    Spezi, Emiliano

    2010-08-01

    Sixty years after the paper 'The Monte Carlo method' by N Metropolis and S Ulam in The Journal of the American Statistical Association (Metropolis and Ulam 1949), use of the most accurate algorithm for computer modelling of radiotherapy linear accelerators, radiation detectors and three dimensional patient dose was discussed in Wales (UK). The Second European Workshop on Monte Carlo Treatment Planning (MCTP2009) was held at the National Museum of Wales in Cardiff. The event, organized by Velindre NHS Trust, Cardiff University and Cancer Research Wales, lasted two and a half days, during which leading experts and contributing authors presented and discussed the latest advances in the field of Monte Carlo treatment planning (MCTP). MCTP2009 was highly successful, judging from the number of participants which was in excess of 140. Of the attendees, 24% came from the UK, 46% from the rest of Europe, 12% from North America and 18% from the rest of the World. Fifty-three oral presentations and 24 posters were delivered in a total of 12 scientific sessions. MCTP2009 follows the success of previous similar initiatives (Verhaegen and Seuntjens 2005, Reynaert 2007, Verhaegen and Seuntjens 2008), and confirms the high level of interest in Monte Carlo technology for radiotherapy treatment planning. The 13 articles selected for this special section (following Physics in Medicine and Biology's usual rigorous peer-review procedure) give a good picture of the high quality of the work presented at MCTP2009. The book of abstracts can be downloaded from http://www.mctp2009.org. I wish to thank the IOP Medical Physics and Computational Physics Groups for their financial support, Elekta Ltd and Dosisoft for sponsoring MCTP2009, and leading manufacturers such as BrainLab, Nucletron and Varian for showcasing their latest MC-based radiotherapy solutions during a dedicated technical session. I am also very grateful to the eight invited speakers who kindly accepted to give keynote

  11. Photon energy-modulated radiotherapy: Monte Carlo simulation and treatment planning study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Min; Kim, Jung-in; Heon Choi, Chang; Chie, Eui Kyu; Kim, Il Han; Ye, Sung-Joon [Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744, Korea and Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of) and Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of); Interdiciplinary Program in Radiation Applied Life Science, Seoul National University, Seoul, 110-744 (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul, 110-744 (Korea, Republic of) and Department of Intelligent Convergence Systems, Seoul National University, Seoul, 151-742 (Korea, Republic of)

    2012-03-15

    Purpose: To demonstrate the feasibility of photon energy-modulated radiotherapy during beam-on time. Methods: A cylindrical device made of aluminum was conceptually proposed as an energy modulator. The frame of the device was connected with 20 tubes through which mercury could be injected or drained to adjust the thickness of mercury along the beam axis. In Monte Carlo (MC) simulations, a flattening filter of 6 or 10 MV linac was replaced with the device. The thickness of mercury inside the device varied from 0 to 40 mm at the field sizes of 5 x 5 cm{sup 2} (FS5), 10 x 10 cm{sup 2} (FS10), and 20 x 20 cm{sup 2} (FS20). At least 5 billion histories were followed for each simulation to create phase space files at 100 cm source to surface distance (SSD). In-water beam data were acquired by additional MC simulations using the above phase space files. A treatment planning system (TPS) was commissioned to generate a virtual machine using the MC-generated beam data. Intensity modulated radiation therapy (IMRT) plans for six clinical cases were generated using conventional 6 MV, 6 MV flattening filter free, and energy-modulated photon beams of the virtual machine. Results: As increasing the thickness of mercury, Percentage depth doses (PDD) of modulated 6 and 10 MV after the depth of dose maximum were continuously increased. The amount of PDD increase at the depth of 10 and 20 cm for modulated 6 MV was 4.8% and 5.2% at FS5, 3.9% and 5.0% at FS10 and 3.2%-4.9% at FS20 as increasing the thickness of mercury from 0 to 20 mm. The same for modulated 10 MV was 4.5% and 5.0% at FS5, 3.8% and 4.7% at FS10 and 4.1% and 4.8% at FS20 as increasing the thickness of mercury from 0 to 25 mm. The outputs of modulated 6 MV with 20 mm mercury and of modulated 10 MV with 25 mm mercury were reduced into 30%, and 56% of conventional linac, respectively. The energy-modulated IMRT plans had less integral doses than 6 MV IMRT or 6 MV flattening filter free plans for tumors located in the

  12. The use of computed tomography images in Monte Carlo treatment planning

    Science.gov (United States)

    Bazalova, Magdalena

    Monte Carlo (MC) dose calculations cannot accurately assess the dose delivered to the patient during radiotherapy unless the patient anatomy is well known. This thesis focuses on the conversion of patient computed tomography (CT) images into MC geometry files. Metal streaking artifacts and their effect on MC dose calculations are first studied. A correction algorithm is applied to artifact-corrupted images and dose errors due to density and tissue mis-assignment are quantified in a phantom and a patient study. The correction algorithm and MC dose calculations for various treatment beams are also investigated using phantoms with real hip prostheses. As a result of this study, we suggest that a metal artifact correction algorithm should be a part of any MC treatment planning. By means of MC simulations, scatter is proven to be a major cause of metal artifacts. The use of dual-energy CT (DECT) for a novel tissue segmentation scheme is thoroughly investigated. First, MC simulations are used to determine the optimal beam filtration for an accurate DECT material extraction. DECT is then tested on a CT scanner with a phantom and a good agreement in the extraction of two material properties, the relative electron density rhoe and the effective atomic number Z is found. Compared to the conventional tissue segmentation based on rhoe-differences, the novel tissue segmentation scheme uses differences in both rhoe and Z. The phantom study demonstrates that the novel method based on rhoe and Z information works well and makes MC dose calculations more accurate. This thesis demonstrates that DECT suppresses streaking artifacts from brachytherapy seeds. Brachytherapy MC dose calculations using single-energy CT images with artifacts and DECT images with suppressed artifacts are performed and the effect of artifact reduction is investigated. The patient and canine DECT studies also show that image noise and object motion are very important factors in DECT. A solution for reduction

  13. Evaluation of an electron Monte Carlo dose calculation algorithm for treatment planning.

    Science.gov (United States)

    Chamberland, Eve; Beaulieu, Luc; Lachance, Bernard

    2015-05-08

    The purpose of this study is to evaluate the accuracy of the electron Monte Carlo (eMC) dose calculation algorithm included in a commercial treatment planning system and compare its performance against an electron pencil beam algorithm. Several tests were performed to explore the system's behavior in simple geometries and in configurations encountered in clinical practice. The first series of tests were executed in a homogeneous water phantom, where experimental measurements and eMC-calculated dose distributions were compared for various combinations of energy and applicator. More specifically, we compared beam profiles and depth-dose curves at different source-to-surface distances (SSDs) and gantry angles, by using dose difference and distance to agreement. Also, we compared output factors, we studied the effects of algorithm input parameters, which are the random number generator seed, as well as the calculation grid size, and we performed a calculation time evaluation. Three different inhomogeneous solid phantoms were built, using high- and low-density materials inserts, to clinically simulate relevant heterogeneity conditions: a small air cylinder within a homogeneous phantom, a lung phantom, and a chest wall phantom. We also used an anthropomorphic phantom to perform comparison of eMC calculations to measurements. Finally, we proceeded with an evaluation of the eMC algorithm on a clinical case of nose cancer. In all mentioned cases, measurements, carried out by means of XV-2 films, radiographic films or EBT2 Gafchromic films. were used to compare eMC calculations with dose distributions obtained from an electron pencil beam algorithm. eMC calculations in the water phantom were accurate. Discrepancies for depth-dose curves and beam profiles were under 2.5% and 2 mm. Dose calculations with eMC for the small air cylinder and the lung phantom agreed within 2% and 4%, respectively. eMC calculations for the chest wall phantom and the anthropomorphic phantom also

  14. Experimental verification of lung dose with radiochromic film: comparison with Monte Carlo simulations and commercially available treatment planning systems

    Science.gov (United States)

    Paelinck, L.; Reynaert, N.; Thierens, H.; DeNeve, W.; DeWagter, C.

    2005-05-01

    The purpose of this study was to assess the absorbed dose in and around lung tissue by performing radiochromic film measurements, Monte Carlo simulations and calculations with superposition convolution algorithms. We considered a layered polystyrene phantom of 12 × 12 × 12 cm3 containing a central cavity of 6 × 6 × 6 cm3 filled with Gammex RMI lung-equivalent material. Two field configurations were investigated, a small 1 × 10 cm2 field and a larger 10 × 10 cm2 field. First, we performed Monte Carlo simulations to investigate the influence of radiochromic film itself on the measured dose distribution when the film intersects a lung-equivalent region and is oriented parallel to the central beam axis. To that end, the film and the lung-equivalent materials were modelled in detail, taking into account their specific composition. Next, measurements were performed with the film oriented both parallel and perpendicular to the central beam axis to verify the results of our Monte Carlo simulations. Finally, we digitized the phantom in two commercially available treatment planning systems, Helax-TMS version 6.1A and Pinnacle version 6.2b, and calculated the absorbed dose in the phantom with their incorporated superposition convolution algorithms to compare with the Monte Carlo simulations. Comparing Monte Carlo simulations with measurements reveals that radiochromic film is a reliable dosimeter in and around lung-equivalent regions when the film is positioned perpendicular to the central beam axis. Radiochromic film is also able to predict the absorbed dose accurately when the film is positioned parallel to the central beam axis through the lung-equivalent region. However, attention must be paid when the film is not positioned along the central beam axis, in which case the film gradually attenuates the beam and decreases the dose measured behind the cavity. This underdosage disappears by offsetting the film a few centimetres. We find deviations of about 3.6% between

  15. Monte Carlo-based treatment planning system calculation engine for microbeam radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Rovira, I.; Sempau, J.; Prezado, Y. [Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, Barcelona E-08028 (Spain) and ID17 Biomedical Beamline, European Synchrotron Radiation Facility (ESRF), 6 rue Jules Horowitz B.P. 220, F-38043 Grenoble Cedex (France); Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, Barcelona E-08028 (Spain); Laboratoire Imagerie et modelisation en neurobiologie et cancerologie, UMR8165, Centre National de la Recherche Scientifique (CNRS), Universites Paris 7 et Paris 11, Bat 440., 15 rue Georges Clemenceau, F-91406 Orsay Cedex (France)

    2012-05-15

    Purpose: Microbeam radiation therapy (MRT) is a synchrotron radiotherapy technique that explores the limits of the dose-volume effect. Preclinical studies have shown that MRT irradiations (arrays of 25-75-{mu}m-wide microbeams spaced by 200-400 {mu}m) are able to eradicate highly aggressive animal tumor models while healthy tissue is preserved. These promising results have provided the basis for the forthcoming clinical trials at the ID17 Biomedical Beamline of the European Synchrotron Radiation Facility (ESRF). The first step includes irradiation of pets (cats and dogs) as a milestone before treatment of human patients. Within this context, accurate dose calculations are required. The distinct features of both beam generation and irradiation geometry in MRT with respect to conventional techniques require the development of a specific MRT treatment planning system (TPS). In particular, a Monte Carlo (MC)-based calculation engine for the MRT TPS has been developed in this work. Experimental verification in heterogeneous phantoms and optimization of the computation time have also been performed. Methods: The penelope/penEasy MC code was used to compute dose distributions from a realistic beam source model. Experimental verification was carried out by means of radiochromic films placed within heterogeneous slab-phantoms. Once validation was completed, dose computations in a virtual model of a patient, reconstructed from computed tomography (CT) images, were performed. To this end, decoupling of the CT image voxel grid (a few cubic millimeter volume) to the dose bin grid, which has micrometer dimensions in the transversal direction of the microbeams, was performed. Optimization of the simulation parameters, the use of variance-reduction (VR) techniques, and other methods, such as the parallelization of the simulations, were applied in order to speed up the dose computation. Results: Good agreement between MC simulations and experimental results was achieved, even at

  16. Full Monte Carlo-Based Biologic Treatment Plan Optimization System for Intensity Modulated Carbon Ion Therapy on Graphics Processing Unit.

    Science.gov (United States)

    Qin, Nan; Shen, Chenyang; Tsai, Min-Yu; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B; Parodi, Katia; Jia, Xun

    2018-01-01

    One of the major benefits of carbon ion therapy is enhanced biological effectiveness at the Bragg peak region. For intensity modulated carbon ion therapy (IMCT), it is desirable to use Monte Carlo (MC) methods to compute the properties of each pencil beam spot for treatment planning, because of their accuracy in modeling physics processes and estimating biological effects. We previously developed goCMC, a graphics processing unit (GPU)-oriented MC engine for carbon ion therapy. The purpose of the present study was to build a biological treatment plan optimization system using goCMC. The repair-misrepair-fixation model was implemented to compute the spatial distribution of linear-quadratic model parameters for each spot. A treatment plan optimization module was developed to minimize the difference between the prescribed and actual biological effect. We used a gradient-based algorithm to solve the optimization problem. The system was embedded in the Varian Eclipse treatment planning system under a client-server architecture to achieve a user-friendly planning environment. We tested the system with a 1-dimensional homogeneous water case and 3 3-dimensional patient cases. Our system generated treatment plans with biological spread-out Bragg peaks covering the targeted regions and sparing critical structures. Using 4 NVidia GTX 1080 GPUs, the total computation time, including spot simulation, optimization, and final dose calculation, was 0.6 hour for the prostate case (8282 spots), 0.2 hour for the pancreas case (3795 spots), and 0.3 hour for the brain case (6724 spots). The computation time was dominated by MC spot simulation. We built a biological treatment plan optimization system for IMCT that performs simulations using a fast MC engine, goCMC. To the best of our knowledge, this is the first time that full MC-based IMCT inverse planning has been achieved in a clinically viable time frame. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Dosimetric study of prostate brachytherapy using techniques of Monte-Carlo simulation, experimental measurements and comparison with a treatment plan

    International Nuclear Information System (INIS)

    Teles, Pedro; Barros, Silvia; Vaz, Pedro; Goncalves, Isabel; Facure, Alessandro; Rosa, Luiz da; Santos, Maira; Pereira Junior, Pedro Paulo; Zankl, Maria

    2013-01-01

    Prostate Brachytherapy is a radiotherapy technique, which consists in inserting a number of radioactive seeds (containing, usually, the following radionuclides 125 l, 241 Am or 103 Pd ) surrounding or in the vicinity of, prostate tumor tissue . The main objective of this technique is to maximize the radiation dose to the tumor and minimize it in other tissues and organs healthy, in order to reduce its morbidity. The absorbed dose distribution in the prostate, using this technique is usually non-homogeneous and time dependent. Various parameters such as the type of seed, the attenuation interactions between them, their geometrical arrangement within the prostate, the actual geometry of the seeds,and further swelling of the prostate gland after implantation greatly influence the course of absorbed dose in the prostate and surrounding areas. Quantification of these parameters is therefore extremely important for dose optimization and improvement of their plans conventional treatment, which in many cases not fully take into account. The Monte Carlo techniques allow to study these parameters quickly and effectively. In this work, we use the program MCNPX and generic voxel phantom (GOLEM) where simulated different geometric arrangements of seeds containing 125 I, Amersham Health model of type 6711 in prostates of different sizes, in order to try to quantify some of the parameters. The computational model was validated using a phantom prostate cubic RW3 type , consisting of tissue equivalent, and thermoluminescent dosimeters. Finally, to have a term of comparison with a treatment real plan it was simulate a treatment plan used in a hospital of Rio de Janeiro, with exactly the same parameters, and our computational model. The results obtained in our study seem to indicate that the parameters described above may be a source of uncertainty in the correct evaluation of the dose required for actual treatment plans. The use of Monte Carlo techniques can serve as a complementary

  18. Dosimetric evaluation of the clinical implementation of the first commercial IMRT Monte Carlo treatment planning system at 6 MV

    International Nuclear Information System (INIS)

    Heath, Emily; Seuntjens, Jan; Sheikh-Bagheri, Daryoush

    2004-01-01

    In this work we dosimetrically evaluated the clinical implementation of a commercial Monte Carlo treatment planning software (PEREGRINE, North American Scientific, Cranberry Township, PA) intended for quality assurance (QA) of intensity modulated radiation therapy treatment plans. Dose profiles calculated in homogeneous and heterogeneous phantoms using this system were compared to both measurements and simulations using the EGSnrc Monte Carlo code for the 6 MV beam of a Varian CL21EX linear accelerator. For simple jaw-defined fields, calculations agree within 2% of the dose at d max with measurements in homogeneous phantoms with the exception of the buildup region where the calculations overestimate the dose by up to 8%. In heterogeneous lung and bone phantoms the agreement is within 3%, on average, up to 5% for a 1x1 cm 2 field. We tested two consecutive implementations of the MLC model. After matching the calculated and measured MLC leakage, simulations of static and dynamic MLC-defined fields using the most recent MLC model agreed to within 2% with measurements

  19. EDITORIAL: Special section: Selected papers from the Third European Workshop on Monte Carlo Treatment Planning (MCTP2012) Special section: Selected papers from the Third European Workshop on Monte Carlo Treatment Planning (MCTP2012)

    Science.gov (United States)

    Spezi, Emiliano; Leal, Antonio

    2013-04-01

    The Third European Workshop on Monte Carlo Treatment Planning (MCTP2012) was held from 15-18 May, 2012 in Seville, Spain. The event was organized by the Universidad de Sevilla with the support of the European Workgroup on Monte Carlo Treatment Planning (EWG-MCTP). MCTP2012 followed two successful meetings, one held in Ghent (Belgium) in 2006 (Reynaert 2007) and one in Cardiff (UK) in 2009 (Spezi 2010). The recurrence of these workshops together with successful events held in parallel by McGill University in Montreal (Seuntjens et al 2012), show consolidated interest from the scientific community in Monte Carlo (MC) treatment planning. The workshop was attended by a total of 90 participants, mainly coming from a medical physics background. A total of 48 oral presentations and 15 posters were delivered in specific scientific sessions including dosimetry, code development, imaging, modelling of photon and electron radiation transport, external beam radiation therapy, nuclear medicine, brachitherapy and hadrontherapy. A copy of the programme is available on the workshop's website (www.mctp2012.com). In this special section of Physics in Medicine and Biology we report six papers that were selected following the journal's rigorous peer review procedure. These papers actually provide a good cross section of the areas of application of MC in treatment planning that were discussed at MCTP2012. Czarnecki and Zink (2013) and Wagner et al (2013) present the results of their work in small field dosimetry. Czarnecki and Zink (2013) studied field size and detector dependent correction factors for diodes and ion chambers within a clinical 6MV photon beam generated by a Siemens linear accelerator. Their modelling work based on the BEAMnrc/EGSnrc codes and experimental measurements revealed that unshielded diodes were the best choice for small field dosimetry because of their independence from the electron beam spot size and correction factor close to unity. Wagner et al (2013

  20. Implementation of the DPM Monte Carlo code on a parallel architecture for treatment planning applications.

    Science.gov (United States)

    Tyagi, Neelam; Bose, Abhijit; Chetty, Indrin J

    2004-09-01

    We have parallelized the Dose Planning Method (DPM), a Monte Carlo code optimized for radiotherapy class problems, on distributed-memory processor architectures using the Message Passing Interface (MPI). Parallelization has been investigated on a variety of parallel computing architectures at the University of Michigan-Center for Advanced Computing, with respect to efficiency and speedup as a function of the number of processors. We have integrated the parallel pseudo random number generator from the Scalable Parallel Pseudo-Random Number Generator (SPRNG) library to run with the parallel DPM. The Intel cluster consisting of 800 MHz Intel Pentium III processor shows an almost linear speedup up to 32 processors for simulating 1 x 10(8) or more particles. The speedup results are nearly linear on an Athlon cluster (up to 24 processors based on availability) which consists of 1.8 GHz+ Advanced Micro Devices (AMD) Athlon processors on increasing the problem size up to 8 x 10(8) histories. For a smaller number of histories (1 x 10(8)) the reduction of efficiency with the Athlon cluster (down to 83.9% with 24 processors) occurs because the processing time required to simulate 1 x 10(8) histories is less than the time associated with interprocessor communication. A similar trend was seen with the Opteron Cluster (consisting of 1400 MHz, 64-bit AMD Opteron processors) on increasing the problem size. Because of the 64-bit architecture Opteron processors are capable of storing and processing instructions at a faster rate and hence are faster as compared to the 32-bit Athlon processors. We have validated our implementation with an in-phantom dose calculation study using a parallel pencil monoenergetic electron beam of 20 MeV energy. The phantom consists of layers of water, lung, bone, aluminum, and titanium. The agreement in the central axis depth dose curves and profiles at different depths shows that the serial and parallel codes are equivalent in accuracy.

  1. Implementation of the DPM Monte Carlo code on a parallel architecture for treatment planning applications

    International Nuclear Information System (INIS)

    Tyagi, Neelam; Bose, Abhijit; Chetty, Indrin J.

    2004-01-01

    We have parallelized the Dose Planning Method (DPM), a Monte Carlo code optimized for radiotherapy class problems, on distributed-memory processor architectures using the Message Passing Interface (MPI). Parallelization has been investigated on a variety of parallel computing architectures at the University of Michigan-Center for Advanced Computing, with respect to efficiency and speedup as a function of the number of processors. We have integrated the parallel pseudo random number generator from the Scalable Parallel Pseudo-Random Number Generator (SPRNG) library to run with the parallel DPM. The Intel cluster consisting of 800 MHz Intel Pentium III processor shows an almost linear speedup up to 32 processors for simulating 1x10 8 or more particles. The speedup results are nearly linear on an Athlon cluster (up to 24 processors based on availability) which consists of 1.8 GHz+ Advanced Micro Devices (AMD) Athlon processors on increasing the problem size up to 8x10 8 histories. For a smaller number of histories (1x10 8 ) the reduction of efficiency with the Athlon cluster (down to 83.9% with 24 processors) occurs because the processing time required to simulate 1x10 8 histories is less than the time associated with interprocessor communication. A similar trend was seen with the Opteron Cluster (consisting of 1400 MHz, 64-bit AMD Opteron processors) on increasing the problem size. Because of the 64-bit architecture Opteron processors are capable of storing and processing instructions at a faster rate and hence are faster as compared to the 32-bit Athlon processors. We have validated our implementation with an in-phantom dose calculation study using a parallel pencil monoenergetic electron beam of 20 MeV energy. The phantom consists of layers of water, lung, bone, aluminum, and titanium. The agreement in the central axis depth dose curves and profiles at different depths shows that the serial and parallel codes are equivalent in accuracy

  2. Sensitivity studies in Monte Carlo treatment planning for neutron brachytherapy of cervical cancer : role of boron augmentation

    International Nuclear Information System (INIS)

    Ralston, A.; Wallace, S.A.; Allen, B.J.

    1996-01-01

    Cervical cancer is the most common malignancy of women in the world and in the third world often presents in an advanced state. While photo radiation therapy is an established form of treatment, neutron brachytherapy with Cf-252 has proven to give superior local control in advanced cases without serious complications. This advantage arises from the reduction in radio-resistance, ascribed to hypoxia in bulky tumours, which occurs with high LET radiation. A further improvement is being sought by dose augmentation with boron neutron capture therapy. The Los Alamos Monte Carlo Neutron Photon radiation transport code MCNP is being used to investigate the effects of fat, muscle, bone and voids in the fast and thermal dose distributions. Whereas the fast neutron dose determines normal tissue tolerance, the boron neutron capture dose rate is determined by the thermal flux distribution. The neutron spectrum is sensitive to changes in hydrogen density, as occurs with muscle, fat and bone. The implications of this sensitivity are examined to determine whether detailed individual Monte Carlo calculations are required for patient clinical treatment plans. (author)

  3. Feasibility assessment of the interactive use of a Monte Carlo algorithm in treatment planning for intraoperative electron radiation therapy

    International Nuclear Information System (INIS)

    Guerra, Pedro; Ledesma-Carbayo, María J; Santos, Andrés; Udías, José M; Herranz, Elena; Herraiz, Joaquín L; Santos-Miranda, Juan Antonio; Calvo, Felipe A; Valdivieso, Manlio F; Rodríguez, Raúl; Illana, Carlos; Calama, Juan A; Pascau, Javier

    2014-01-01

    This work analysed the feasibility of using a fast, customized Monte Carlo (MC) method to perform accurate computation of dose distributions during pre- and intraplanning of intraoperative electron radiation therapy (IOERT) procedures. The MC method that was implemented, which has been integrated into a specific innovative simulation and planning tool, is able to simulate the fate of thousands of particles per second, and it was the aim of this work to determine the level of interactivity that could be achieved. The planning workflow enabled calibration of the imaging and treatment equipment, as well as manipulation of the surgical frame and insertion of the protection shields around the organs at risk and other beam modifiers. In this way, the multidisciplinary team involved in IOERT has all the tools necessary to perform complex MC dosage simulations adapted to their equipment in an efficient and transparent way. To assess the accuracy and reliability of this MC technique, dose distributions for a monoenergetic source were compared with those obtained using a general-purpose software package used widely in medical physics applications. Once accuracy of the underlying simulator was confirmed, a clinical accelerator was modelled and experimental measurements in water were conducted. A comparison was made with the output from the simulator to identify the conditions under which accurate dose estimations could be obtained in less than 3 min, which is the threshold imposed to allow for interactive use of the tool in treatment planning. Finally, a clinically relevant scenario, namely early-stage breast cancer treatment, was simulated with pre- and intraoperative volumes to verify that it was feasible to use the MC tool intraoperatively and to adjust dose delivery based on the simulation output, without compromising accuracy. The workflow provided a satisfactory model of the treatment head and the imaging system, enabling proper configuration of the treatment planning

  4. Fred: a GPU-accelerated fast-Monte Carlo code for rapid treatment plan recalculation in ion beam therapy

    Science.gov (United States)

    Schiavi, A.; Senzacqua, M.; Pioli, S.; Mairani, A.; Magro, G.; Molinelli, S.; Ciocca, M.; Battistoni, G.; Patera, V.

    2017-09-01

    Ion beam therapy is a rapidly growing technique for tumor radiation therapy. Ions allow for a high dose deposition in the tumor region, while sparing the surrounding healthy tissue. For this reason, the highest possible accuracy in the calculation of dose and its spatial distribution is required in treatment planning. On one hand, commonly used treatment planning software solutions adopt a simplified beam-body interaction model by remapping pre-calculated dose distributions into a 3D water-equivalent representation of the patient morphology. On the other hand, Monte Carlo (MC) simulations, which explicitly take into account all the details in the interaction of particles with human tissues, are considered to be the most reliable tool to address the complexity of mixed field irradiation in a heterogeneous environment. However, full MC calculations are not routinely used in clinical practice because they typically demand substantial computational resources. Therefore MC simulations are usually only used to check treatment plans for a restricted number of difficult cases. The advent of general-purpose programming GPU cards prompted the development of trimmed-down MC-based dose engines which can significantly reduce the time needed to recalculate a treatment plan with respect to standard MC codes in CPU hardware. In this work, we report on the development of fred, a new MC simulation platform for treatment planning in ion beam therapy. The code can transport particles through a 3D voxel grid using a class II MC algorithm. Both primary and secondary particles are tracked and their energy deposition is scored along the trajectory. Effective models for particle-medium interaction have been implemented, balancing accuracy in dose deposition with computational cost. Currently, the most refined module is the transport of proton beams in water: single pencil beam dose-depth distributions obtained with fred agree with those produced by standard MC codes within 1-2% of the

  5. The use of Monte-Carlo codes for treatment planning in external-beam radiotherapy

    International Nuclear Information System (INIS)

    Alan, E.; Nahum, PhD.

    2003-01-01

    Monte Carlo simulation of radiation transport is a very powerful technique. There are basically no exact solutions to the Boltzmann transport equation. Even, the 'straightforward' situation (in radiotherapy) of an electron beam depth-dose distribution in water proves to be too difficult for analytical methods without making gross approximations such as ignoring energy-loss straggling, large-angle single scattering and Bremsstrahlung production. monte Carlo is essential when radiation is transport from one medium into another. As the particle (be it a neutron, photon, electron, proton) crosses the boundary then a new set of interaction cross-sections is simply read in and the simulation continues as though the new medium were infinite until the next boundary is encountered. Radiotherapy involves directing a beam of megavoltage x rays or electrons (occasionally protons) at a very complex object, the human body. Monte Carlo simulation has proved in valuable at many stages of the process of accurately determining the distribution of absorbed dose in the patient. Some of these applications will be reviewed here. (Rogers and al 1990; Andreo 1991; Mackie 1990). (N.C.)

  6. 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.

  7. SU-E-T-222: Computational Optimization of Monte Carlo Simulation On 4D Treatment Planning Using the Cloud Computing Technology

    International Nuclear Information System (INIS)

    Chow, J

    2015-01-01

    Purpose: This study evaluated the efficiency of 4D lung radiation treatment planning using Monte Carlo simulation on the cloud. The EGSnrc Monte Carlo code was used in dose calculation on the 4D-CT image set. Methods: 4D lung radiation treatment plan was created by the DOSCTP linked to the cloud, based on the Amazon elastic compute cloud platform. Dose calculation was carried out by Monte Carlo simulation on the 4D-CT image set on the cloud, and results were sent to the FFD4D image deformation program for dose reconstruction. The dependence of computing time for treatment plan on the number of compute node was optimized with variations of the number of CT image set in the breathing cycle and dose reconstruction time of the FFD4D. Results: It is found that the dependence of computing time on the number of compute node was affected by the diminishing return of the number of node used in Monte Carlo simulation. Moreover, the performance of the 4D treatment planning could be optimized by using smaller than 10 compute nodes on the cloud. The effects of the number of image set and dose reconstruction time on the dependence of computing time on the number of node were not significant, as more than 15 compute nodes were used in Monte Carlo simulations. Conclusion: The issue of long computing time in 4D treatment plan, requiring Monte Carlo dose calculations in all CT image sets in the breathing cycle, can be solved using the cloud computing technology. It is concluded that the optimized number of compute node selected in simulation should be between 5 and 15, as the dependence of computing time on the number of node is significant

  8. A Monte Carlo pencil beam scanning model for proton treatment plan simulation using GATE/GEANT4

    Energy Technology Data Exchange (ETDEWEB)

    Grevillot, L; Freud, N; Sarrut, D [Universite de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Universite Lyon 1, Centre Leon Berard, Lyon (France); Bertrand, D; Dessy, F, E-mail: loic.grevillot@creatis.insa-lyon.fr [IBA, B-1348, Louvain-la Neuve (Belgium)

    2011-08-21

    This work proposes a generic method for modeling scanned ion beam delivery systems, without simulation of the treatment nozzle and based exclusively on beam data library (BDL) measurements required for treatment planning systems (TPS). To this aim, new tools dedicated to treatment plan simulation were implemented in the Gate Monte Carlo platform. The method was applied to a dedicated nozzle from IBA for proton pencil beam scanning delivery. Optical and energy parameters of the system were modeled using a set of proton depth-dose profiles and spot sizes measured at 27 therapeutic energies. For further validation of the beam model, specific 2D and 3D plans were produced and then measured with appropriate dosimetric tools. Dose contributions from secondary particles produced by nuclear interactions were also investigated using field size factor experiments. Pristine Bragg peaks were reproduced with 0.7 mm range and 0.2 mm spot size accuracy. A 32 cm range spread-out Bragg peak with 10 cm modulation was reproduced with 0.8 mm range accuracy and a maximum point-to-point dose difference of less than 2%. A 2D test pattern consisting of a combination of homogeneous and high-gradient dose regions passed a 2%/2 mm gamma index comparison for 97% of the points. In conclusion, the generic modeling method proposed for scanned ion beam delivery systems was applicable to an IBA proton therapy system. The key advantage of the method is that it only requires BDL measurements of the system. The validation tests performed so far demonstrated that the beam model achieves clinical performance, paving the way for further studies toward TPS benchmarking. The method involves new sources that are available in the new Gate release V6.1 and could be further applied to other particle therapy systems delivering protons or other types of ions like carbon.

  9. A Monte Carlo pencil beam scanning model for proton treatment plan simulation using GATE/GEANT4.

    Science.gov (United States)

    Grevillot, L; Bertrand, D; Dessy, F; Freud, N; Sarrut, D

    2011-08-21

    This work proposes a generic method for modeling scanned ion beam delivery systems, without simulation of the treatment nozzle and based exclusively on beam data library (BDL) measurements required for treatment planning systems (TPS). To this aim, new tools dedicated to treatment plan simulation were implemented in the Gate Monte Carlo platform. The method was applied to a dedicated nozzle from IBA for proton pencil beam scanning delivery. Optical and energy parameters of the system were modeled using a set of proton depth-dose profiles and spot sizes measured at 27 therapeutic energies. For further validation of the beam model, specific 2D and 3D plans were produced and then measured with appropriate dosimetric tools. Dose contributions from secondary particles produced by nuclear interactions were also investigated using field size factor experiments. Pristine Bragg peaks were reproduced with 0.7 mm range and 0.2 mm spot size accuracy. A 32 cm range spread-out Bragg peak with 10 cm modulation was reproduced with 0.8 mm range accuracy and a maximum point-to-point dose difference of less than 2%. A 2D test pattern consisting of a combination of homogeneous and high-gradient dose regions passed a 2%/2 mm gamma index comparison for 97% of the points. In conclusion, the generic modeling method proposed for scanned ion beam delivery systems was applicable to an IBA proton therapy system. The key advantage of the method is that it only requires BDL measurements of the system. The validation tests performed so far demonstrated that the beam model achieves clinical performance, paving the way for further studies toward TPS benchmarking. The method involves new sources that are available in the new Gate release V6.1 and could be further applied to other particle therapy systems delivering protons or other types of ions like carbon.

  10. Quality control of the treatment planning systems dose calculations in external radiation therapy using the Penelope Monte Carlo code; Controle qualite des systemes de planification dosimetrique des traitements en radiotherapie externe au moyen du code Monte-Carlo Penelope

    Energy Technology Data Exchange (ETDEWEB)

    Blazy-Aubignac, L

    2007-09-15

    The treatment planning systems (T.P.S.) occupy a key position in the radiotherapy service: they realize the projected calculation of the dose distribution and the treatment duration. Traditionally, the quality control of the calculated distribution doses relies on their comparisons with dose distributions measured under the device of treatment. This thesis proposes to substitute these dosimetry measures to the profile of reference dosimetry calculations got by the Penelope Monte-Carlo code. The Monte-Carlo simulations give a broad choice of test configurations and allow to envisage a quality control of dosimetry aspects of T.P.S. without monopolizing the treatment devices. This quality control, based on the Monte-Carlo simulations has been tested on a clinical T.P.S. and has allowed to simplify the quality procedures of the T.P.S.. This quality control, in depth, more precise and simpler to implement could be generalized to every center of radiotherapy. (N.C.)

  11. Clinical implementation of a GPU-based simplified Monte Carlo method for a treatment planning system of proton beam therapy.

    Science.gov (United States)

    Kohno, R; Hotta, K; Nishioka, S; Matsubara, K; Tansho, R; Suzuki, T

    2011-11-21

    We implemented the simplified Monte Carlo (SMC) method on graphics processing unit (GPU) architecture under the computer-unified device architecture platform developed by NVIDIA. The GPU-based SMC was clinically applied for four patients with head and neck, lung, or prostate cancer. The results were compared to those obtained by a traditional CPU-based SMC with respect to the computation time and discrepancy. In the CPU- and GPU-based SMC calculations, the estimated mean statistical errors of the calculated doses in the planning target volume region were within 0.5% rms. The dose distributions calculated by the GPU- and CPU-based SMCs were similar, within statistical errors. The GPU-based SMC showed 12.30-16.00 times faster performance than the CPU-based SMC. The computation time per beam arrangement using the GPU-based SMC for the clinical cases ranged 9-67 s. The results demonstrate the successful application of the GPU-based SMC to a clinical proton treatment planning.

  12. Analysis of Various Multi-Objective Optimization Evolutionary Algorithms for Monte Carlo Treatment Planning System

    CERN Document Server

    Tydrichova, Magdalena

    2017-01-01

    In this project, various available multi-objective optimization evolutionary algorithms were compared considering their performance and distribution of solutions. The main goal was to select the most suitable algorithms for applications in cancer hadron therapy planning. For our purposes, a complex testing and analysis software was developed. Also, many conclusions and hypothesis have been done for the further research.

  13. A new approach to integrate GPU-based Monte Carlo simulation into inverse treatment plan optimization for proton therapy.

    Science.gov (United States)

    Li, Yongbao; Tian, Zhen; Song, Ting; Wu, Zhaoxia; Liu, Yaqiang; Jiang, Steve; Jia, Xun

    2017-01-07

    Monte Carlo (MC)-based spot dose calculation is highly desired for inverse treatment planning in proton therapy because of its accuracy. Recent studies on biological optimization have also indicated the use of MC methods to compute relevant quantities of interest, e.g. linear energy transfer. Although GPU-based MC engines have been developed to address inverse optimization problems, their efficiency still needs to be improved. Also, the use of a large number of GPUs in MC calculation is not favorable for clinical applications. The previously proposed adaptive particle sampling (APS) method can improve the efficiency of MC-based inverse optimization by using the computationally expensive MC simulation more effectively. This method is more efficient than the conventional approach that performs spot dose calculation and optimization in two sequential steps. In this paper, we propose a computational library to perform MC-based spot dose calculation on GPU with the APS scheme. The implemented APS method performs a non-uniform sampling of the particles from pencil beam spots during the optimization process, favoring those from the high intensity spots. The library also conducts two computationally intensive matrix-vector operations frequently used when solving an optimization problem. This library design allows a streamlined integration of the MC-based spot dose calculation into an existing proton therapy inverse planning process. We tested the developed library in a typical inverse optimization system with four patient cases. The library achieved the targeted functions by supporting inverse planning in various proton therapy schemes, e.g. single field uniform dose, 3D intensity modulated proton therapy, and distal edge tracking. The efficiency was 41.6  ±  15.3% higher than the use of a GPU-based MC package in a conventional calculation scheme. The total computation time ranged between 2 and 50 min on a single GPU card depending on the problem size.

  14. SU-E-T-587: Monte Carlo Versus Ray-Tracing for Treatment Planning Involving CNS Tumors On the MultiPlan System for CyberKnife Radiosurgery

    International Nuclear Information System (INIS)

    Forbang, R Teboh

    2014-01-01

    Purpose: MultiPlan, the treatment planning system for the CyberKnife Robotic Radiosurgery system offers two approaches to dose computation, namely Ray-Tracing (RT), the default technique and Monte Carlo (MC), an option. RT is deterministic, however it accounts for primary heterogeneity only. MC on the other hand has an uncertainty associated with the calculation results. The advantage is that in addition, it accounts for heterogeneity effects on the scattered dose. Not all sites will benefit from MC. The goal of this work was to focus on central nervous system (CNS) tumors and compare dosimetrically, treatment plans computed with RT versus MC. Methods: Treatment plans were computed using both RT and MC for sites covering (a) the brain (b) C-spine (c) upper T-spine (d) lower T-spine (e) L-spine and (f) sacrum. RT was first used to compute clinically valid treatment plans. Then the same treatment parameters, monitor units, beam weights, etc., were used in the MC algorithm to compute the dose distribution. The plans were then compared for tumor coverage to illustrate the difference if any. All MC calculations were performed at a 1% uncertainty. Results: Using the RT technique, the tumor coverage for the brain, C-spine (C3–C7), upper T-spine (T4–T6), lower T-spine (T10), Lspine (L2) and sacrum were 96.8%, 93.1%, 97.2%, 87.3%, 91.1%, and 95.3%. The corresponding tumor coverage based on the MC approach was 98.2%, 95.3%, 87.55%, 88.2%, 92.5%, and 95.3%. It should be noted that the acceptable planning target coverage for our clinical practice is >95%. The coverage can be compromised for spine tumors to spare normal tissues such as the spinal cord. Conclusion: For treatment planning involving the CNS, RT and MC appear to be similar for most sites but for the T-spine area where most of the beams traverse lung tissue. In this case, MC is highly recommended

  15. Treatment plan evaluation for interstitial photodynamic therapy in a mouse model by Monte Carlo simulation with FullMonte

    Directory of Open Access Journals (Sweden)

    Jeffrey eCassidy

    2015-02-01

    Full Text Available Monte Carlo (MC simulation is recognized as the gold standard for biophotonic simulation, capturing all relevant physics and material properties at the perceived cost of high computing demands. Tetrahedral-mesh-based MC simulations particularly are attractive due to the ability to refine the mesh at will to conform to complicated geometries or user-defined resolution requirements. Since no approximations of material or light-source properties are required, MC methods are applicable to the broadest set of biophotonic simulation problems. MC methods also have other implementation features including inherent parallelism, and permit a continuously-variable quality-runtime tradeoff. We demonstrate here a complete MC-based prospective fluence dose evaluation system for interstitial PDT to generate dose-volume histograms on a tetrahedral mesh geometry description. To our knowledge, this is the first such system for general interstitial photodynamic therapy employing MC methods and is therefore applicable to a very broad cross-section of anatomy and material properties. We demonstrate that evaluation of dose-volume histograms is an effective variance-reduction scheme in its own right which greatly reduces the number of packets required and hence runtime required to achieve acceptable result confidence. We conclude that MC methods are feasible for general PDT treatment evaluation and planning, and considerably less costly than widely believed.

  16. Monte Carlo evaluation of the AAA treatment planning algorithm in a heterogeneous multilayer phantom and IMRT clinical treatments for an Elekta SL25 linear accelerator

    International Nuclear Information System (INIS)

    Sterpin, E.; Tomsej, M.; Smedt, B. de; Reynaert, N.; Vynckier, S.

    2007-01-01

    The Anisotropic Analytical Algorithm (AAA) is a new pencil beam convolution/superposition algorithm proposed by Varian for photon dose calculations. The configuration of AAA depends on linear accelerator design and specifications. The purpose of this study was to investigate the accuracy of AAA for an Elekta SL25 linear accelerator for small fields and intensity modulated radiation therapy (IMRT) treatments in inhomogeneous media. The accuracy of AAA was evaluated in two studies. First, AAA was compared both with Monte Carlo (MC) and the measurements in an inhomogeneous phantom simulating lung equivalent tissues and bone ribs. The algorithm was tested under lateral electronic disequilibrium conditions, using small fields (2x2 cm 2 ). Good agreement was generally achieved for depth dose and profiles, with deviations generally below 3% in lung inhomogeneities and below 5% at interfaces. However, the effects of attenuation and scattering close to the bone ribs were not fully taken into account by AAA, and small inhomogeneities may lead to planning errors. Second, AAA and MC were compared for IMRT plans in clinical conditions, i.e., dose calculations in a computed tomography scan of a patient. One ethmoid tumor, one orophaxynx and two lung tumors are presented in this paper. Small differences were found between the dose volume histograms. For instance, a 1.7% difference for the mean planning target volume dose was obtained for the ethmoid case. Since better agreement was achieved for the same plans but in homogeneous conditions, these differences must be attributed to the handling of inhomogeneities by AAA. Therefore, inherent assumptions of the algorithm, principally the assumption of independent depth and lateral directions in the scaling of the kernels, were slightly influencing AAA's validity in inhomogeneities. However, AAA showed a good accuracy overall and a great ability to handle small fields in inhomogeneous media compared to other pencil beam convolution

  17. OEDIPE, a software for personalized Monte Carlo dosimetry and treatment planning optimization in nuclear medicine: absorbed dose and biologically effective dose considerations

    International Nuclear Information System (INIS)

    Petitguillaume, A.; Broggio, D.; Franck, D.; Desbree, A.; Bernardini, M.; Labriolle Vaylet, C. de

    2014-01-01

    For targeted radionuclide therapies, treatment planning usually consists of the administration of standard activities without accounting for the patient-specific activity distribution, pharmacokinetics and dosimetry to organs at risk. The OEDIPE software is a user-friendly interface which has an automation level suitable for performing personalized Monte Carlo 3D dosimetry for diagnostic and therapeutic radionuclide administrations. Mean absorbed doses to regions of interest (ROIs), isodose curves superimposed on a personalized anatomical model of the patient and dose-volume histograms can be extracted from the absorbed dose 3D distribution. Moreover, to account for the differences in radiosensitivity between tumoral and healthy tissues, additional functionalities have been implemented to calculate the 3D distribution of the biologically effective dose (BED), mean BEDs to ROIs, isoBED curves and BED-volume histograms along with the Equivalent Uniform Biologically Effective Dose (EUD) to ROIs. Finally, optimization tools are available for treatment planning optimization using either the absorbed dose or BED distributions. These tools enable one to calculate the maximal injectable activity which meets tolerance criteria to organs at risk for a chosen fractionation protocol. This paper describes the functionalities available in the latest version of the OEDIPE software to perform personalized Monte Carlo dosimetry and treatment planning optimization in targeted radionuclide therapies. (authors)

  18. Retinoblastoma external beam photon irradiation with a special ‘D’-shaped collimator: a comparison between measurements, Monte Carlo simulation and a treatment planning system calculation

    Science.gov (United States)

    Brualla, L.; Mayorga, P. A.; Flühs, A.; Lallena, A. M.; Sempau, J.; Sauerwein, W.

    2012-11-01

    Retinoblastoma is the most common eye tumour in childhood. According to the available long-term data, the best outcome regarding tumour control and visual function has been reached by external beam radiotherapy. The benefits of the treatment are, however, jeopardized by a high incidence of radiation-induced secondary malignancies and the fact that irradiated bones grow asymmetrically. In order to better exploit the advantages of external beam radiotherapy, it is necessary to improve current techniques by reducing the irradiated volume and minimizing the dose to the facial bones. To this end, dose measurements and simulated data in a water phantom are essential. A Varian Clinac 2100 C/D operating at 6 MV is used in conjunction with a dedicated collimator for the retinoblastoma treatment. This collimator conforms a ‘D’-shaped off-axis field whose irradiated area can be either 5.2 or 3.1 cm2. Depth dose distributions and lateral profiles were experimentally measured. Experimental results were compared with Monte Carlo simulations’ run with the penelope code and with calculations performed with the analytical anisotropic algorithm implemented in the Eclipse treatment planning system using the gamma test. penelope simulations agree reasonably well with the experimental data with discrepancies in the dose profiles less than 3 mm of distance to agreement and 3% of dose. Discrepancies between the results found with the analytical anisotropic algorithm and the experimental data reach 3 mm and 6%. Although the discrepancies between the results obtained with the analytical anisotropic algorithm and the experimental data are notable, it is possible to consider this algorithm for routine treatment planning of retinoblastoma patients, provided the limitations of the algorithm are known and taken into account by the medical physicist and the clinician. Monte Carlo simulation is essential for knowing these limitations. Monte Carlo simulation is required for optimizing the

  19. The Adjoint Method for The Optimization of Brachytherapy and Radiotherapy Patient Treatment Planning Procedures Using Monte Carlo Calculations

    International Nuclear Information System (INIS)

    Henderson, D.L.; Yoo, S.; Kowalok, M.; Mackie, T.R.; Thomadsen, B.R.

    2001-01-01

    The goal of this project is to investigate the use of the adjoint method, commonly used in the reactor physics community, for the optimization of radiation therapy patient treatment plans. Two different types of radiation therapy are being examined, interstitial brachytherapy and radiotherapy. In brachytherapy radioactive sources are surgically implanted within the diseased organ such as the prostate to treat the cancerous tissue. With radiotherapy, the x-ray source is usually located at a distance of about 1-meter from the patient and focused on the treatment area. For brachytherapy the optimization phase of the treatment plan consists of determining the optimal placement of the radioactive sources, which delivers the prescribed dose to the disease tissue while simultaneously sparing (reducing) the dose to sensitive tissue and organs. For external beam radiation therapy the optimization phase of the treatment plan consists of determining the optimal direction and intensity of beam, which provides complete coverage of the tumor region with the prescribed dose while simultaneously avoiding sensitive tissue areas. For both therapy methods, the optimal treatment plan is one in which the diseased tissue has been treated with the prescribed dose and dose to the sensitive tissue and organs has been kept to a minimum

  20. The Adjoint Method for The Optimization of Brachytherapy and Radiotherapy Patient Treatment Planning Procedures Using Monte Carlo Calculations

    Energy Technology Data Exchange (ETDEWEB)

    D.L. Henderson; S. Yoo; M. Kowalok; T.R. Mackie; B.R. Thomadsen

    2001-10-30

    The goal of this project is to investigate the use of the adjoint method, commonly used in the reactor physics community, for the optimization of radiation therapy patient treatment plans. Two different types of radiation therapy are being examined, interstitial brachytherapy and radiotherapy. In brachytherapy radioactive sources are surgically implanted within the diseased organ such as the prostate to treat the cancerous tissue. With radiotherapy, the x-ray source is usually located at a distance of about 1-metere from the patient and focused on the treatment area. For brachytherapy the optimization phase of the treatment plan consists of determining the optimal placement of the radioactive sources, which delivers the prescribed dose to the disease tissue while simultaneously sparing (reducing) the dose to sensitive tissue and organs. For external beam radiation therapy the optimization phase of the treatment plan consists of determining the optimal direction and intensity of beam, which provides complete coverage of the tumor region with the prescribed dose while simultaneously avoiding sensitive tissue areas. For both therapy methods, the optimal treatment plan is one in which the diseased tissue has been treated with the prescribed dose and dose to the sensitive tissue and organs has been kept to a minimum.

  1. TU-EF-304-07: Monte Carlo-Based Inverse Treatment Plan Optimization for Intensity Modulated Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y [Tsinghua University, Beijing, Beijing (China); UT Southwestern Medical Center, Dallas, TX (United States); Tian, Z; Jiang, S; Jia, X [UT Southwestern Medical Center, Dallas, TX (United States); Song, T [Southern Medical University, Guangzhou, Guangdong (China); UT Southwestern Medical Center, Dallas, TX (United States); Wu, Z; Liu, Y [Tsinghua University, Beijing, Beijing (China)

    2015-06-15

    Purpose: Intensity-modulated proton therapy (IMPT) is increasingly used in proton therapy. For IMPT optimization, Monte Carlo (MC) is desired for spots dose calculations because of its high accuracy, especially in cases with a high level of heterogeneity. It is also preferred in biological optimization problems due to the capability of computing quantities related to biological effects. However, MC simulation is typically too slow to be used for this purpose. Although GPU-based MC engines have become available, the achieved efficiency is still not ideal. The purpose of this work is to develop a new optimization scheme to include GPU-based MC into IMPT. Methods: A conventional approach using MC in IMPT simply calls the MC dose engine repeatedly for each spot dose calculations. However, this is not the optimal approach, because of the unnecessary computations on some spots that turned out to have very small weights after solving the optimization problem. GPU-memory writing conflict occurring at a small beam size also reduces computational efficiency. To solve these problems, we developed a new framework that iteratively performs MC dose calculations and plan optimizations. At each dose calculation step, the particles were sampled from different spots altogether with Metropolis algorithm, such that the particle number is proportional to the latest optimized spot intensity. Simultaneously transporting particles from multiple spots also mitigated the memory writing conflict problem. Results: We have validated the proposed MC-based optimization schemes in one prostate case. The total computation time of our method was ∼5–6 min on one NVIDIA GPU card, including both spot dose calculation and plan optimization, whereas a conventional method naively using the same GPU-based MC engine were ∼3 times slower. Conclusion: A fast GPU-based MC dose calculation method along with a novel optimization workflow is developed. The high efficiency makes it attractive for clinical

  2. TU-EF-304-07: Monte Carlo-Based Inverse Treatment Plan Optimization for Intensity Modulated Proton Therapy

    International Nuclear Information System (INIS)

    Li, Y; Tian, Z; Jiang, S; Jia, X; Song, T; Wu, Z; Liu, Y

    2015-01-01

    Purpose: Intensity-modulated proton therapy (IMPT) is increasingly used in proton therapy. For IMPT optimization, Monte Carlo (MC) is desired for spots dose calculations because of its high accuracy, especially in cases with a high level of heterogeneity. It is also preferred in biological optimization problems due to the capability of computing quantities related to biological effects. However, MC simulation is typically too slow to be used for this purpose. Although GPU-based MC engines have become available, the achieved efficiency is still not ideal. The purpose of this work is to develop a new optimization scheme to include GPU-based MC into IMPT. Methods: A conventional approach using MC in IMPT simply calls the MC dose engine repeatedly for each spot dose calculations. However, this is not the optimal approach, because of the unnecessary computations on some spots that turned out to have very small weights after solving the optimization problem. GPU-memory writing conflict occurring at a small beam size also reduces computational efficiency. To solve these problems, we developed a new framework that iteratively performs MC dose calculations and plan optimizations. At each dose calculation step, the particles were sampled from different spots altogether with Metropolis algorithm, such that the particle number is proportional to the latest optimized spot intensity. Simultaneously transporting particles from multiple spots also mitigated the memory writing conflict problem. Results: We have validated the proposed MC-based optimization schemes in one prostate case. The total computation time of our method was ∼5–6 min on one NVIDIA GPU card, including both spot dose calculation and plan optimization, whereas a conventional method naively using the same GPU-based MC engine were ∼3 times slower. Conclusion: A fast GPU-based MC dose calculation method along with a novel optimization workflow is developed. The high efficiency makes it attractive for clinical

  3. Dosimetric verification in water of a Monte Carlo treatment planning tool for proton, helium, carbon and oxygen ion beams at the Heidelberg Ion Beam Therapy Center

    Science.gov (United States)

    Tessonnier, T.; Böhlen, T. T.; Ceruti, F.; Ferrari, A.; Sala, P.; Brons, S.; Haberer, T.; Debus, J.; Parodi, K.; Mairani, A.

    2017-08-01

    The introduction of ‘new’ ion species in particle therapy needs to be supported by a thorough assessment of their dosimetric properties and by treatment planning comparisons with clinically used proton and carbon ion beams. In addition to the latter two ions, helium and oxygen ion beams are foreseen at the Heidelberg Ion Beam Therapy Center (HIT) as potential assets for improving clinical outcomes in the near future. We present in this study a dosimetric validation of a FLUKA-based Monte Carlo treatment planning tool (MCTP) for protons, helium, carbon and oxygen ions for spread-out Bragg peaks in water. The comparisons between the ions show the dosimetric advantages of helium and heavier ion beams in terms of their distal and lateral fall-offs with respect to protons, reducing the lateral size of the region receiving 50% of the planned dose up to 12 mm. However, carbon and oxygen ions showed significant doses beyond the target due to the higher fragmentation tail compared to lighter ions (p and He), up to 25%. The Monte Carlo predictions were found to be in excellent geometrical agreement with the measurements, with deviations below 1 mm for all parameters investigated such as target and lateral size as well as distal fall-offs. Measured and simulated absolute dose values agreed within about 2.5% on the overall dose distributions. The MCTP tool, which supports the usage of multiple state-of-the-art relative biological effectiveness models, will provide a solid engine for treatment planning comparisons at HIT.

  4. Dosimetric verification in water of a Monte Carlo treatment planning tool for proton, helium, carbon and oxygen ion beams at the Heidelberg Ion Beam Therapy Center.

    Science.gov (United States)

    Tessonnier, T; Böhlen, T T; Ceruti, F; Ferrari, A; Sala, P; Brons, S; Haberer, T; Debus, J; Parodi, K; Mairani, A

    2017-07-31

    The introduction of 'new' ion species in particle therapy needs to be supported by a thorough assessment of their dosimetric properties and by treatment planning comparisons with clinically used proton and carbon ion beams. In addition to the latter two ions, helium and oxygen ion beams are foreseen at the Heidelberg Ion Beam Therapy Center (HIT) as potential assets for improving clinical outcomes in the near future. We present in this study a dosimetric validation of a FLUKA-based Monte Carlo treatment planning tool (MCTP) for protons, helium, carbon and oxygen ions for spread-out Bragg peaks in water. The comparisons between the ions show the dosimetric advantages of helium and heavier ion beams in terms of their distal and lateral fall-offs with respect to protons, reducing the lateral size of the region receiving 50% of the planned dose up to 12 mm. However, carbon and oxygen ions showed significant doses beyond the target due to the higher fragmentation tail compared to lighter ions (p and He), up to 25%. The Monte Carlo predictions were found to be in excellent geometrical agreement with the measurements, with deviations below 1 mm for all parameters investigated such as target and lateral size as well as distal fall-offs. Measured and simulated absolute dose values agreed within about 2.5% on the overall dose distributions. The MCTP tool, which supports the usage of multiple state-of-the-art relative biological effectiveness models, will provide a solid engine for treatment planning comparisons at HIT.

  5. Report of the AAPM Task Group No. 105: Issues associated with clinical implementation of Monte Carlo-based photon and electron external beam treatment planning

    International Nuclear Information System (INIS)

    Chetty, Indrin J.; Curran, Bruce; Cygler, Joanna E.; DeMarco, John J.; Ezzell, Gary; Faddegon, Bruce A.; Kawrakow, Iwan; Keall, Paul J.; Liu, Helen; Ma, C.-M. Charlie; Rogers, D. W. O.; Seuntjens, Jan; Sheikh-Bagheri, Daryoush; Siebers, Jeffrey V.

    2007-01-01

    The Monte Carlo (MC) method has been shown through many research studies to calculate accurate dose distributions for clinical radiotherapy, particularly in heterogeneous patient tissues where the effects of electron transport cannot be accurately handled with conventional, deterministic dose algorithms. Despite its proven accuracy and the potential for improved dose distributions to influence treatment outcomes, the long calculation times previously associated with MC simulation rendered this method impractical for routine clinical treatment planning. However, the development of faster codes optimized for radiotherapy calculations and improvements in computer processor technology have substantially reduced calculation times to, in some instances, within minutes on a single processor. These advances have motivated several major treatment planning system vendors to embark upon the path of MC techniques. Several commercial vendors have already released or are currently in the process of releasing MC algorithms for photon and/or electron beam treatment planning. Consequently, the accessibility and use of MC treatment planning algorithms may well become widespread in the radiotherapy community. With MC simulation, dose is computed stochastically using first principles; this method is therefore quite different from conventional dose algorithms. Issues such as statistical uncertainties, the use of variance reduction techniques, the ability to account for geometric details in the accelerator treatment head simulation, and other features, are all unique components of a MC treatment planning algorithm. Successful implementation by the clinical physicist of such a system will require an understanding of the basic principles of MC techniques. The purpose of this report, while providing education and review on the use of MC simulation in radiotherapy planning, is to set out, for both users and developers, the salient issues associated with clinical implementation and

  6. Clinical introduction of Monte Carlo treatment planning: A different prescription dose for non-small cell lung cancer according to tumor location and size

    International Nuclear Information System (INIS)

    Voort van Zyp, Noelle C. van der; Hoogeman, Mischa S.; Water, Steven van de; Levendag, Peter C.; Holt, Bronno van der; Heijmen, Ben J.M.; Nuyttens, Joost J.

    2010-01-01

    Purpose: To provide a prescription dose for Monte Carlo (MC) treatment planning in patients with non-small-cell lung cancer according to tumor size and location. Methods: Fifty-three stereotactic radiotherapy plans designed using the equivalent path-length (EPL) algorithm were re-calculated using MC. Plans were compared by the minimum dose to 95% of the PTV (D95), the heterogeneity index (HI) and the mean dose to organs at risk (OARs). Based on changes in D95, the prescription dose was converted from EPL to MC. Based on changes in HI, we examined the feasibility of MC prescription to plans re-calculated but not re-optimized with MC. Results: The MC fraction dose for peripheral tumors is 16-18 Gy depending on tumor size. For central tumors the MC dose was reduced less than for peripheral tumors. The HI decreased on average by 4-9% in peripheral tumors and 3-5% in central tumors. The mean dose to OARs was lower for MC than EPL, and correlated strongly (R 2 = 0.98-0.99). Conclusion: For the conversion from EPL to MC we recommend a separate prescription dose according to tumor size. MC optimization is not required if a HI ≥ 70% is accepted. Dose constraints to OARs can be easily converted due to the high EPL-MC correlation.

  7. 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...

  8. MO-A-BRD-10: A Fast and Accurate GPU-Based Proton Transport Monte Carlo Simulation for Validating Proton Therapy Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Wan Chan Tseung, H; Ma, J; Beltran, C [Mayo Clinic, Rochester, MN (United States)

    2014-06-15

    Purpose: To build a GPU-based Monte Carlo (MC) simulation of proton transport with detailed modeling of elastic and non-elastic (NE) protonnucleus interactions, for use in a very fast and cost-effective proton therapy treatment plan verification system. Methods: Using the CUDA framework, we implemented kernels for the following tasks: (1) Simulation of beam spots from our possible scanning nozzle configurations, (2) Proton propagation through CT geometry, taking into account nuclear elastic and multiple scattering, as well as energy straggling, (3) Bertini-style modeling of the intranuclear cascade stage of NE interactions, and (4) Simulation of nuclear evaporation. To validate our MC, we performed: (1) Secondary particle yield calculations in NE collisions with therapeutically-relevant nuclei, (2) Pencil-beam dose calculations in homogeneous phantoms, (3) A large number of treatment plan dose recalculations, and compared with Geant4.9.6p2/TOPAS. A workflow was devised for calculating plans from a commercially available treatment planning system, with scripts for reading DICOM files and generating inputs for our MC. Results: Yields, energy and angular distributions of secondaries from NE collisions on various nuclei are in good agreement with the Geant4.9.6p2 Bertini and Binary cascade models. The 3D-gamma pass rate at 2%–2mm for 70–230 MeV pencil-beam dose distributions in water, soft tissue, bone and Ti phantoms is 100%. The pass rate at 2%–2mm for treatment plan calculations is typically above 98%. The net computational time on a NVIDIA GTX680 card, including all CPU-GPU data transfers, is around 20s for 1×10{sup 7} proton histories. Conclusion: Our GPU-based proton transport MC is the first of its kind to include a detailed nuclear model to handle NE interactions on any nucleus. Dosimetric calculations demonstrate very good agreement with Geant4.9.6p2/TOPAS. Our MC is being integrated into a framework to perform fast routine clinical QA of pencil

  9. Determining the distribution of the absorbed dose for a body exposed to Cs-137 using the Monte Carlo method and application in a brachytherapy treatment planning

    International Nuclear Information System (INIS)

    Randriantsizafy, R.D.

    2014-01-01

    Brachytherapy is a means of precise and effective cancer treatment. This is due to the nearby sources of ionizing radiation. The precision and efficiency requires a good dosimetry and a good knowledge of the dose distribution in the patient. The aim is to give the right dose of ionizing radiation to destroy the tumor while reducing the dose to sensitive organs such as the bladder , liver, .... The Monte Carlo is a recognized model method for the distribution of radiation in the material. It is used in this work to determine the doses to organs during treatment planning for Cesium -137 brachytherapy. The programming language used is Python . Library outcome of this work is used in a web application BrachyPy, we designed to replace the manual processing in the Cs-137 brachytherapy planning. Model validation is done by comparing the isodose curves of the model with the isodose curves abacus NUCLETRON and the last report of the American Association of Medical Physics (AAPM) on the amendment to the algorithm TG43. [fr

  10. Estimating statistical uncertainty of Monte Carlo efficiency-gain in the context of a correlated sampling Monte Carlo code for brachytherapy treatment planning with non-normal dose distribution

    Czech Academy of Sciences Publication Activity Database

    Mukhopadhyay, N. D.; Sampson, A. J.; Deniz, D.; Carlsson, G. A.; Williamson, J.; Malušek, Alexandr

    2012-01-01

    Roč. 70, č. 1 (2012), s. 315-323 ISSN 0969-8043 Institutional research plan: CEZ:AV0Z10480505 Keywords : Monte Carlo * correlated sampling * efficiency * uncertainty * bootstrap Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.179, year: 2012 http://www.sciencedirect.com/science/article/pii/S0969804311004775

  11. SU-E-T-157: CARMEN: A MatLab-Based Research Platform for Monte Carlo Treatment Planning (MCTP) and Customized System for Planning Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Baeza, J.A.; Ureba, A.; Jimenez-Ortega, E.; Barbeiro, A.R.; Plaza, A. Leal [Universidad de Sevilla, Departamento de Fisiologia Medica y Biofisica, Seville (Spain); Lagares, J.I. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Madrid (Spain)

    2015-06-15

    Purpose: Although there exist several radiotherapy research platforms, such as: CERR, the most widely used and referenced; SlicerRT, which allows treatment plan comparison from various sources; and MMCTP, a full MCTP system; it is still needed a full MCTP toolset that provides users complete control of calculation grids, interpolation methods and filters in order to “fairly” compare results from different TPSs, supporting verification with experimental measurements. Methods: This work presents CARMEN, a MatLab-based platform including multicore and GPGPU accelerated functions for loading RT data; designing treatment plans; and evaluating dose matrices and experimental data.CARMEN supports anatomic and functional imaging in DICOM format, as well as RTSTRUCT, RTPLAN and RTDOSE. Besides, it contains numerous tools to accomplish the MCTP process, managing egs4phant and phase space files.CARMEN planning mode assist in designing IMRT, VMAT and MERT treatments via both inverse and direct optimization. The evaluation mode contains a comprehensive toolset (e.g. 2D/3D gamma evaluation, difference matrices, profiles, DVH, etc.) to compare datasets from commercial TPS, MC simulations (i.e. 3ddose) and radiochromic film in a user-controlled manner. Results: CARMEN has been validated against commercial RTPs and well-established evaluation tools, showing coherent behavior of its multiple algorithms. Furthermore, CARMEN platform has been used to generate competitive complex treatment that has been published in comparative studies. Conclusion: A new research oriented MCTP platform with a customized validation toolset has been presented. Despite of being coded with a high-level programming language, CARMEN is agile due to the use of parallel algorithms. The wide-spread use of MatLab provides straightforward access to CARMEN’s algorithms to most researchers. Similarly, our platform can benefit from the MatLab community scientific developments as filters, registration algorithms

  12. MATLAB platform for Monte Carlo planning and dosimetry experimental evaluation

    International Nuclear Information System (INIS)

    Baeza, J. A.; Ureba, A.; Jimenez-Ortega, E.; Pereira-Barbeiro, A. R.; Leal, A.

    2013-01-01

    A new platform for the full Monte Carlo planning and an independent experimental evaluation that it can be integrated into clinical practice. The tool has proved its usefulness and efficiency and now forms part of the flow of work of our research group, the tool used for the generation of results, which are to be suitably revised and are being published. This software is an effort of integration of numerous algorithms of image processing, along with planning optimization algorithms, allowing the process of MCTP planning from a single interface. In addition, becomes a flexible and accurate tool for the evaluation of experimental dosimetric data for the quality control of actual treatments. (Author)

  13. Dosimetric quality control of treatment planning systems in external radiation therapy using Digital Test Objects calculated by PENELOPE Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Ben Hdech, Yassine

    2011-01-01

    To ensure the required accuracy and prevent from mis-administration, cancer treatments, by external radiation therapy are simulated on Treatment Planning System or TPS before radiation delivery in order to ensure that the prescription is achieved both in terms of target volumes coverage and healthy tissues protection. The TPS calculates the patient dose distribution and the treatment time per beam required to deliver the prescribed dose. TPS is a key system in the decision process of treatment by radiation therapy. It is therefore essential that the TPS be subject to a thorough check of its performance (quality control or QC) and in particular its ability to accurately compute dose distributions for patients in all clinical situations that be met. The 'traditional' methods recommended to carry out dosimetric CQ of algorithms implemented in the TPS are based on comparisons between dose distributions calculated with the TPS and dose measured in physical test objects (PTO) using the treatment machine. In this thesis we propose to substitute the reference dosimetric measurements performed in OTP by benchmark dose calculations in Digital Test Objects using PENELOPE Monte-Carlo code. This method has three advantages: (i) it allows simulation in situations close to the clinic and often too complex to be experimentally feasible; (ii) due to the digital form of reference data the QC process may be automated; (iii) it allows a comprehensive TPS CQ without hindering the use of an equipment devoted primarily to patients treatments. This new method of CQ has been tested successfully on the Eclipse TPS from Varian Medical Systems Company. (author) [fr

  14. Personalized Monte Carlo dosimetry for the planning and evaluation of internal radiotherapy treatments: development and application to selective internal radiotherapy (SIRT)

    International Nuclear Information System (INIS)

    Petitguillaume, Alice

    2014-01-01

    Medical techniques in full expansion arousing high therapeutic expectations, targeted radionuclide therapies (TRT) consist of administering a radiopharmaceutical to selectively treat tumors. Nowadays, the activity injected to the patient is generally standardized. However, in order to establish robust dose-effect relationships and to optimize treatments while sparing healthy tissues at best, a personalized dosimetry must be performed, just like actual clinical practice in external beam radiotherapy. In that context, this PhD main objective was to develop, using the OEDIPE software, a methodology for personalized dosimetry based on direct Monte Carlo calculations. The developed method enables to calculate the tridimensional distribution of absorbed doses depending on the patient anatomy, defined from CT or MRI data, and on the patient-specific activity biodistribution, defined from SPECT or PET data. Radiobiological aspects, such as differences in radiosensitivities and repair time constants between tumoral and healthy tissues, have also been integrated through the linear-quadratic model. This methodology has been applied to the selective internal radiation therapy (SIRT) which consists in the injection of 90 Y-microspheres to selectively treat unresectable hepatic cancers. Distributions of absorbed doses and biologically effective doses (BED) along with the equivalent uniform biologically effective doses (EUD) to hepatic lesions have been calculated from 99m Tc-MAA activity distributions obtained during the evaluation step for 18 patients treated at Hopital Europeen Georges Pompidou. Those results have been compared to classical methods used in clinics and the interest of accurate and personalized dosimetry for treatment planning has been investigated. On the one hand, the possibility to increase the activity in a personalized way has been highlighted with the calculation of the maximal activity that could be injected to the patient while meeting tolerance criteria

  15. A Monte Carlo program converting activity distribution to absorbed dose distributions in a radionuclide treatment planning system

    International Nuclear Information System (INIS)

    Tagesson, M.; Ljungberg, M.; Strand, S.E.

    1996-01-01

    In systemic radiation therapy, the absorbed dose distribution must be calculated from the individual activity distribution. A computer code has been developed for the conversion of an arbitrary activity distribution to a 3-D absorbed dose distribution. The activity distribution can be described either analytically or as a voxel based distribution, which comes from a SPECT acquisition. Decay points are sampled according to the activity map, and particles (photons and electrons) from the decay are followed through the tissue until they either escape the patient or drop below a cut off energy. To verify the calculated results, the mathematically defined MIRD phantom and unity density spheres have been included in the code. Also other published dosimetry data were used for verification. Absorbed fraction and S-values were calculated. A comparison with simulated data from the code with MIRD data shows good agreement. The S values are within 10-20% of published MIRD S values for most organs. Absorbed fractions for photons and electrons in spheres (masses between 1 g and 200 kg) are within 10-15% of those published. Radial absorbed dose distributions in a necrotic tumor show good agreement with published data. The application of the code in a radionuclide therapy dose planning system, based on quantitative SPECT, is discussed. (orig.)

  16. SBRT of lung tumours: Monte Carlo simulation with PENELOPE of dose distributions including respiratory motion and comparison with different treatment planning systems

    Science.gov (United States)

    Panettieri, Vanessa; Wennberg, Berit; Gagliardi, Giovanna; Amor Duch, Maria; Ginjaume, Mercè; Lax, Ingmar

    2007-07-01

    The purpose of this work was to simulate with the Monte Carlo (MC) code PENELOPE the dose distribution in lung tumours including breathing motion in stereotactic body radiation therapy (SBRT). Two phantoms were modelled to simulate a pentagonal cross section with chestwall (unit density), lung (density 0.3 g cm-3) and two spherical tumours (unit density) of diameters respectively of 2 cm and 5 cm. The phase-space files (PSF) of four different SBRT field sizes of 6 MV from a Varian accelerator were calculated and used as beam sources to obtain both dose profiles and dose-volume histograms (DVHs) in different volumes of interest. Dose distributions were simulated for five beams impinging on the phantom. The simulations were conducted both for the static case and including the influence of respiratory motion. To reproduce the effect of breathing motion different simulations were performed keeping the beam fixed and displacing the phantom geometry in chosen positions in the cranial and caudal and left-right directions. The final result was obtained by combining the different position with two motion patterns. The MC results were compared with those obtained with three commercial treatment planning systems (TPSs), two based on the pencil beam (PB) algorithm, the TMS-HELAX (Nucletron, Sweden) and Eclipse (Varian Medical System, Palo Alto, CA), and one based on the collapsed cone algorithm (CC), Pinnacle3 (Philips). Some calculations were also carried out with the analytical anisotropic algorithm (AAA) in the Eclipse system. All calculations with the TPSs were performed without simulated breathing motion, according to clinical practice. In order to compare all the TPSs and MC an absolute dose calibration in Gy/MU was performed. The analysis shows that the dose (Gy/MU) in the central part of the gross tumour volume (GTV) is calculated for both tumour sizes with an accuracy of 2-3% with PB and CC algorithms, compared to MC. At the periphery of the GTV the TPSs overestimate

  17. MATLAB platform for Monte Carlo planning and dosimetry experimental evaluation; Plataforma Matlab para planificacion Monte Carlo y evaluacion dosimetrica experimental

    Energy Technology Data Exchange (ETDEWEB)

    Baeza, J. A.; Ureba, A.; Jimenez-Ortega, E.; Pereira-Barbeiro, A. R.; Leal, A.

    2013-07-01

    A new platform for the full Monte Carlo planning and an independent experimental evaluation that it can be integrated into clinical practice. The tool has proved its usefulness and efficiency and now forms part of the flow of work of our research group, the tool used for the generation of results, which are to be suitably revised and are being published. This software is an effort of integration of numerous algorithms of image processing, along with planning optimization algorithms, allowing the process of MCTP planning from a single interface. In addition, becomes a flexible and accurate tool for the evaluation of experimental dosimetric data for the quality control of actual treatments. (Author)

  18. GPU-Monte Carlo based fast IMRT plan optimization

    Directory of Open Access Journals (Sweden)

    Yongbao Li

    2014-03-01

    Full Text Available Purpose: Intensity-modulated radiation treatment (IMRT plan optimization needs pre-calculated beamlet dose distribution. Pencil-beam or superposition/convolution type algorithms are typically used because of high computation speed. However, inaccurate beamlet dose distributions, particularly in cases with high levels of inhomogeneity, may mislead optimization, hindering the resulting plan quality. It is desire to use Monte Carlo (MC methods for beamlet dose calculations. Yet, the long computational time from repeated dose calculations for a number of beamlets prevents this application. It is our objective to integrate a GPU-based MC dose engine in lung IMRT optimization using a novel two-steps workflow.Methods: A GPU-based MC code gDPM is used. Each particle is tagged with an index of a beamlet where the source particle is from. Deposit dose are stored separately for beamlets based on the index. Due to limited GPU memory size, a pyramid space is allocated for each beamlet, and dose outside the space is neglected. A two-steps optimization workflow is proposed for fast MC-based optimization. At first step, a rough dose calculation is conducted with only a few number of particle per beamlet. Plan optimization is followed to get an approximated fluence map. In the second step, more accurate beamlet doses are calculated, where sampled number of particles for a beamlet is proportional to the intensity determined previously. A second-round optimization is conducted, yielding the final result.Results: For a lung case with 5317 beamlets, 105 particles per beamlet in the first round, and 108 particles per beam in the second round are enough to get a good plan quality. The total simulation time is 96.4 sec.Conclusion: A fast GPU-based MC dose calculation method along with a novel two-step optimization workflow are developed. The high efficiency allows the use of MC for IMRT optimizations.--------------------------------Cite this article as: Li Y, Tian Z

  19. Monte Carlo calculations supporting patient plan verification in proton therapy

    Directory of Open Access Journals (Sweden)

    Thiago Viana Miranda Lima

    2016-03-01

    Full Text Available Patient’s treatment plan verification covers substantial amount of the quality assurance (QA resources, this is especially true for Intensity Modulated Proton Therapy (IMPT. The use of Monte Carlo (MC simulations in supporting QA has been widely discussed and several methods have been proposed. In this paper we studied an alternative approach from the one being currently applied clinically at Centro Nazionale di Adroterapia Oncologica (CNAO. We reanalysed the previously published data (Molinelli et al. 2013, where 9 patient plans were investigated in which the warning QA threshold of 3% mean dose deviation was crossed. The possibility that these differences between measurement and calculated dose were related to dose modelling (Treatment Planning Systems (TPS vs MC, limitations on dose delivery system or detectors mispositioning was originally explored but other factors such as the geometric description of the detectors were not ruled out. For the purpose of this work we compared ionisation-chambers measurements with different MC simulations results. It was also studied some physical effects introduced by this new approach for example inter detector interference and the delta ray thresholds. The simulations accounting for a detailed geometry typically are superior (statistical difference - p-value around 0.01 to most of the MC simulations used at CNAO (only inferior to the shift approach used. No real improvement were observed in reducing the current delta-ray threshold used (100 keV and no significant interference between ion chambers in the phantom were detected (p-value 0.81. In conclusion, it was observed that the detailed geometrical description improves the agreement between measurement and MC calculations in some cases. But in other cases position uncertainty represents the dominant uncertainty. The inter chamber disturbance was not detected for the therapeutic protons energies and the results from the current delta threshold are

  20. Dosimetric study of prostate brachytherapy using techniques of Monte-Carlo simulation, experimental measurements and comparison with a treatment plan; Estudo dosimetrico de braquiterapia da prostata utilizando tecnicas de simulacao de Monte-Carlo, medidas experimentais, e comparacao com um procedimento de plano de tratamento

    Energy Technology Data Exchange (ETDEWEB)

    Teles, Pedro; Barros, Silvia; Vaz, Pedro; Goncalves, Isabel [Instituto Tecnologico e Nuclear, Sacavem (Portugal). Instituto Superior Tecnico; Cardoso, Simone [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Facure, Alessandro [Comissao Nacional de Energia Nuclear, Rio de Janeiro, RJ (Brazil); Rosa, Luiz da; Santos, Maira [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Pereira Junior, Pedro Paulo [Dosimetrika (Brazil); Zankl, Maria [German Research Centre for Environmental Health, Munchen (Germany). Helmholtz Zentrum Munchen

    2013-10-01

    Prostate Brachytherapy is a radiotherapy technique, which consists in inserting a number of radioactive seeds (containing, usually, the following radionuclides {sup 125} l, {sup 241}Am or {sup 103}Pd ) surrounding or in the vicinity of, prostate tumor tissue . The main objective of this technique is to maximize the radiation dose to the tumor and minimize it in other tissues and organs healthy, in order to reduce its morbidity. The absorbed dose distribution in the prostate, using this technique is usually non-homogeneous and time dependent. Various parameters such as the type of seed, the attenuation interactions between them, their geometrical arrangement within the prostate, the actual geometry of the seeds,and further swelling of the prostate gland after implantation greatly influence the course of absorbed dose in the prostate and surrounding areas. Quantification of these parameters is therefore extremely important for dose optimization and improvement of their plans conventional treatment, which in many cases not fully take into account. The Monte Carlo techniques allow to study these parameters quickly and effectively. In this work, we use the program MCNPX and generic voxel phantom (GOLEM) where simulated different geometric arrangements of seeds containing {sup 125}I, Amersham Health model of type 6711 in prostates of different sizes, in order to try to quantify some of the parameters. The computational model was validated using a phantom prostate cubic RW3 type , consisting of tissue equivalent, and thermoluminescent dosimeters. Finally, to have a term of comparison with a treatment real plan it was simulate a treatment plan used in a hospital of Rio de Janeiro, with exactly the same parameters, and our computational model. The results obtained in our study seem to indicate that the parameters described above may be a source of uncertainty in the correct evaluation of the dose required for actual treatment plans. The use of Monte Carlo techniques can

  1. Nuclear data treatment for SAM-CE Monte Carlo calculations

    International Nuclear Information System (INIS)

    Lichtenstein, H.; Troubetzkoy, E.S.; Beer, M.

    1980-01-01

    The treatment of nuclear data by the SAM-CE Monte Carlo code system is presented. The retrieval of neutron, gamma production, and photon data from the ENDF/B fils is described. Integral cross sections as well as differential data are utilized in the Monte Carlo calculations, and the processing procedures for the requisite data are summarized

  2. Concepts of radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Mackie, R.T.

    2000-01-01

    Full text: Radiotherapy treatment planning (RTP) relies heavily on medical imaging. Until recently, the most important planning tool was the treatment simulator. The kilovoltage radiographic capabilities in a treatment simulator enabled the boundaries of treatment fields to be visualized with respect to bony anatomic landmarks. Perhaps the most important advance in treatment planning in recent years is the ability to visualize the passage of the beams with respect to a more accurate geometrical representation of the tumor and other soft tissue structures. This 'virtual simulation' uses a computer-based representation of a patient to determine the extent of the disease and the location of radiation sensitive normal tissue. Computer tomographic (CT) imaging produces a high-resolution three-dimensional representation of anatomy that can be correlated with other image sets such as magnetic resonance images (MRI) of function. Positron emission tomographic (PET) imaging is beginning to be used to determine tumor proliferation and the presence of distant disease. It is likely that accurate RTP in conjunction with CT simulators will eliminate traditional treatment simulators in the future. Traditionally, patient dose calculation algorithms have been based on correcting measured dose in water phantoms to take into account beam modifiers, patient surface contours and internal tissue inhomogeneities. Recently, model-based algorithms have been computing the dose directly in the patient representation using the CT to obtain a voxel-by-voxel density map. The convolution/superposition method, which uses a Monte Carlo-derived transport kernel, is the current state-of-the-art algorithm for dose computation. Soon direct Monte Carlo simulation will be used in model-based dose computation. Model-based dose computations enable a simpler monitor unit calculation formulation. The other major breakthrough in RTP is computer-based optimization. The goals of the treatment are specified as

  3. Computerized radiation treatment planning

    International Nuclear Information System (INIS)

    Laarse, R. van der.

    1981-01-01

    Following a general introduction, a chain consisting of three computer programs which has been developed for treatment planning of external beam radiotherapy without manual intervention is described. New score functions used for determination of optimal incidence directions are presented and the calculation of the position of the isocentre for each optimum combination of incidence directions is explained. A description of how a set of applicators, covering fields with dimensions of 4 to 20 cm, for the 6 to 20 MeV electron beams of a MEL SL75-20 linear accelerator was developed, is given. A computer program for three dimensional electron beam treatment planning is presented. A microprocessor based treatment planning system for the Selectron remote controlled afterloading system for intracavitary radiotherapy is described. The main differences in treatment planning procedures for external beam therapy with neutrons instead of photons is discussed. A microprocessor based densitometer for plotting isodensity lines in film dosimetry is described. A computer program for dose planning of brachytherapy is presented. Finally a general discussion about the different aspects of computerized treatment planning as presented in this thesis is given. (Auth.)

  4. The evolution of brachytherapy treatment planning

    International Nuclear Information System (INIS)

    Rivard, Mark J.; Venselaar, Jack L. M.; Beaulieu, Luc

    2009-01-01

    Brachytherapy is a mature treatment modality that has benefited from technological advances. Treatment planning has advanced from simple lookup tables to complex, computer-based dose-calculation algorithms. The current approach is based on the AAPM TG-43 formalism with recent advances in acquiring single-source dose distributions. However, this formalism has clinically relevant limitations for calculating patient dose. Dose-calculation algorithms are being developed based on Monte Carlo methods, collapsed cone, and solving the linear Boltzmann transport equation. In addition to improved dose-calculation tools, planning systems and brachytherapy treatment planning will account for material heterogeneities, scatter conditions, radiobiology, and image guidance. The AAPM, ESTRO, and other professional societies are working to coordinate clinical integration of these advancements. This Vision 20/20 article provides insight into these endeavors.

  5. RapidArc treatment verification in 3D using polymer gel dosimetry and Monte Carlo simulation

    DEFF Research Database (Denmark)

    Ceberg, Sofie; Gagne, Isabel; Gustafsson, Helen

    2010-01-01

    The aim of this study was to verify the advanced inhomogeneous dose distribution produced by a volumetric arc therapy technique (RapidArc™) using 3D gel measurements and Monte Carlo (MC) simulations. The TPS (treatment planning system)-calculated dose distribution was compared with gel measurements...... and MC simulations, thus investigating any discrepancy between the planned dose delivery and the actual delivery. Additionally, the reproducibility of the delivery was investigated using repeated gel measurements. A prostate treatment plan was delivered to a 1.3 liter nPAG gel phantom using one single...... surface (VOI90), for the TPS versus gel and TPS versus MC. The differences between the verification methods, MC versus gel, and between two repeated gel measurements were investigated in the same way. For all volume comparisons, the mean value was within 1% and the standard deviation of the differences...

  6. Integral multidisciplinary rehabilitation treatment planning

    NARCIS (Netherlands)

    Braaksma, Aleida; Kortbeek, Nikky; Post, Gerhard F.; Nollet, F.

    2014-01-01

    This paper presents a methodology to plan treatments for rehabilitation outpatients. These patients require a series of treatments by therapists from various disciplines. In current practice, when treatments are planned, a lack of coordination between the different disciplines, along with a failure

  7. Integral multidisciplinary rehabilitation treatment planning

    NARCIS (Netherlands)

    Braaksma, Aleida; Kortbeek, Nikky; Post, Gerhard F.; Nollet, Frans

    This paper presents a methodology to plan treatments for rehabilitation outpatients. These patients require a series of treatments by therapists from various disciplines. In current practice, when treatments are planned, a lack of coordination between the different disciplines, along with a failure

  8. Acceptance and implementation of a system of planning computerized based on Monte Carlo

    International Nuclear Information System (INIS)

    Lopez-Tarjuelo, J.; Garcia-Molla, R.; Suan-Senabre, X. J.; Quiros-Higueras, J. Q.; Santos-Serra, A.; Marco-Blancas, N.; Calzada-Feliu, S.

    2013-01-01

    It has been done the acceptance for use clinical Monaco computerized planning system, based on an on a virtual model of the energy yield of the head of the linear electron Accelerator and that performs the calculation of the dose with an algorithm of x-rays (XVMC) based on Monte Carlo algorithm. (Author)

  9. Monte Carlo Planning Method Estimates Planning Horizons during Interactive Social Exchange

    Science.gov (United States)

    Hula, Andreas; Montague, P. Read; Dayan, Peter

    2015-01-01

    Reciprocating interactions represent a central feature of all human exchanges. They have been the target of various recent experiments, with healthy participants and psychiatric populations engaging as dyads in multi-round exchanges such as a repeated trust task. Behaviour in such exchanges involves complexities related to each agent’s preference for equity with their partner, beliefs about the partner’s appetite for equity, beliefs about the partner’s model of their partner, and so on. Agents may also plan different numbers of steps into the future. Providing a computationally precise account of the behaviour is an essential step towards understanding what underlies choices. A natural framework for this is that of an interactive partially observable Markov decision process (IPOMDP). However, the various complexities make IPOMDPs inordinately computationally challenging. Here, we show how to approximate the solution for the multi-round trust task using a variant of the Monte-Carlo tree search algorithm. We demonstrate that the algorithm is efficient and effective, and therefore can be used to invert observations of behavioural choices. We use generated behaviour to elucidate the richness and sophistication of interactive inference. PMID:26053429

  10. Monte Carlo Planning Method Estimates Planning Horizons during Interactive Social Exchange.

    Directory of Open Access Journals (Sweden)

    Andreas Hula

    2015-06-01

    Full Text Available Reciprocating interactions represent a central feature of all human exchanges. They have been the target of various recent experiments, with healthy participants and psychiatric populations engaging as dyads in multi-round exchanges such as a repeated trust task. Behaviour in such exchanges involves complexities related to each agent's preference for equity with their partner, beliefs about the partner's appetite for equity, beliefs about the partner's model of their partner, and so on. Agents may also plan different numbers of steps into the future. Providing a computationally precise account of the behaviour is an essential step towards understanding what underlies choices. A natural framework for this is that of an interactive partially observable Markov decision process (IPOMDP. However, the various complexities make IPOMDPs inordinately computationally challenging. Here, we show how to approximate the solution for the multi-round trust task using a variant of the Monte-Carlo tree search algorithm. We demonstrate that the algorithm is efficient and effective, and therefore can be used to invert observations of behavioural choices. We use generated behaviour to elucidate the richness and sophistication of interactive inference.

  11. Concepts and Plans towards fast large scale Monte Carlo production for the ATLAS Experiment

    CERN Document Server

    Chapman, J; Duehrssen, M; Elsing, M; Froidevaux, D; Harrington, R; Jansky, R; Langenberg, R; Mandrysch, R; Marshall, Z; Ritsch, E; Salzburger, A

    2014-01-01

    The huge success of the physics program of the ATLAS experiment at the Large Hadron Collider (LHC) during run I relies upon a great number of simulated Monte Carlo events. This Monte Carlo production takes the biggest part of the computing resources being in use by ATLAS as of now. In this document we describe the plans to overcome the computing resource limitations for large scale Monte Carlo production in the ATLAS Experiment for run II, and beyond. A number of fast detector simulation, digitization and reconstruction techniques and are being discussed, based upon a new flexible detector simulation framework. To optimally benefit from these developments, a redesigned ATLAS MC production chain is presented at the end of this document.

  12. Interactively exploring optimized treatment plans.

    Science.gov (United States)

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

    2005-02-01

    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. 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. 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 for the minimum PTV dose. Based on the root

  13. SU-C-BRC-03: Development of a Novel Strategy for On-Demand Monte Carlo and Deterministic Dose Calculation Treatment Planning and Optimization for External Beam Photon and Particle Therapy

    International Nuclear Information System (INIS)

    Yang, Y M; Bush, K; Han, B; Xing, L

    2016-01-01

    Purpose: Accurate and fast dose calculation is a prerequisite of precision radiation therapy in modern photon and particle therapy. While Monte Carlo (MC) dose calculation provides high dosimetric accuracy, the drastically increased computational time hinders its routine use. Deterministic dose calculation methods are fast, but problematic in the presence of tissue density inhomogeneity. We leverage the useful features of deterministic methods and MC to develop a hybrid dose calculation platform with autonomous utilization of MC and deterministic calculation depending on the local geometry, for optimal accuracy and speed. Methods: Our platform utilizes a Geant4 based “localized Monte Carlo” (LMC) method that isolates MC dose calculations only to volumes that have potential for dosimetric inaccuracy. In our approach, additional structures are created encompassing heterogeneous volumes. Deterministic methods calculate dose and energy fluence up to the volume surfaces, where the energy fluence distribution is sampled into discrete histories and transported using MC. Histories exiting the volume are converted back into energy fluence, and transported deterministically. By matching boundary conditions at both interfaces, deterministic dose calculation account for dose perturbations “downstream” of localized heterogeneities. Hybrid dose calculation was performed for water and anthropomorphic phantoms. Results: We achieved <1% agreement between deterministic and MC calculations in the water benchmark for photon and proton beams, and dose differences of 2%–15% could be observed in heterogeneous phantoms. The saving in computational time (a factor ∼4–7 compared to a full Monte Carlo dose calculation) was found to be approximately proportional to the volume of the heterogeneous region. Conclusion: Our hybrid dose calculation approach takes advantage of the computational efficiency of deterministic method and accuracy of MC, providing a practical tool for high

  14. Treatment planning for restorative implantology.

    Science.gov (United States)

    Boyce, Ricardo A; Klemons, Gary

    2015-04-01

    In this article, current literature on fixed and removable prosthodontics is reviewed along with evidence-based systematic reviews, including advice from those in the dental profession with years of experience, which help restorative dentists manage and treat their cases successfully. Treatment planning for restorative implantology should be looked at in 4 sections: (1) review of past medical history, (2) oral examination and occlusion, (3) dental imaging (ie, cone-beam computed tomography), and (4) fixed versus removable prosthodontics. These 4 concepts of treatment planning, along with proper surgical placements of the implant(s), result in successful cases. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Acceptance and implementation of a system of planning computerized based on Monte Carlo; Aceptacion y puesta en marcha de un sistema de planificacion comutarizada basado en Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Tarjuelo, J.; Garcia-Molla, R.; Suan-Senabre, X. J.; Quiros-Higueras, J. Q.; Santos-Serra, A.; Marco-Blancas, N.; Calzada-Feliu, S.

    2013-07-01

    It has been done the acceptance for use clinical Monaco computerized planning system, based on an on a virtual model of the energy yield of the head of the linear electron Accelerator and that performs the calculation of the dose with an algorithm of x-rays (XVMC) based on Monte Carlo algorithm. (Author)

  16. Optimizing portal dose calculation for an amorphous silicon detector using Swiss Monte Carlo Plan

    International Nuclear Information System (INIS)

    Frauchiger, D; Fix, M K; Frei, D; Volken, W; Mini, R; Manser, P

    2007-01-01

    Purpose: Modern treatment planning systems (TPS) are able to calculate doses within the patient for numerous delivery techniques as e. g. intensity modulated radiation therapy (IMRT). Even dose predictions to an electronic portal image device (EPID) are available in some TPS, but with limitations in accuracy. With the steadily increasing number of facilities using EPIDs for pre-treatment and treatment verification, the desire of calculating accurate EPID dose distributions is growing. A solution for this problem is the use of Monte Carlo (MC) methods. Aims of this study were firstly to implement geometries of an amorphous silicon based EPID with varying levels of geometry complexity. Secondly to analyze the differences between simulation results and measurements for each geometry. Thirdly, to compare different transport algorithms within all EPID geometries in a flexible C++ MC environment. Materials and Methods: In this work three geometry sets, representing the EPID, are implemented and investigated. To gain flexibility in the MC environment geometry and particle transport code are independent. That allows the user to select between the transport algorithms EGSnrc, VMC++ and PIN (an in-house developed transport code) while using one of the implemented geometries of the EPID. For all implemented EPID geometries dose distributions were calculated for 6 MV and 15 MV beams using different transport algorithms and are then compared with measurements. Results: A very simple geometry, consisting of a water slab, is not capable to reproduce measurements, whereas 8 material layers perform well. The more layers with different materials are used, the longer last the calculations. EGSnrc and VMC++ lead to dosimetrically equal results. Gamma analysis between calculated and measured EPID dose distributions, using a dose difference criterion of ± 3% and a distance to agreement criterion of ± 3 mm, revealed a gamma value < 1 within more than 95% of all pixels, that have a

  17. Monte Carlo calculations and measurements of absorbed dose per monitor unit for the treatment of uveal melanoma with proton therapy

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Nicholas; Newhauser, Wayne D; Titt, Uwe; Starkschall, George [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); Gombos, Dan [Section of Ophthalmology, Department of Head and Neck Surgery MDACC Unit 441 (United States); Coombes, Kevin [Graduate School of Biomedical Sciences, University of Texas Health Science Center, 6767 Bertner Avenue, Houston, TX 77030 (United States)], E-mail: kochn@musc.edu

    2008-03-21

    The treatment of uveal melanoma with proton radiotherapy has provided excellent clinical outcomes. However, contemporary treatment planning systems use simplistic dose algorithms that limit the accuracy of relative dose distributions. Further, absolute predictions of absorbed dose per monitor unit are not yet available in these systems. The purpose of this study was to determine if Monte Carlo methods could predict dose per monitor unit (D/MU) value at the center of a proton spread-out Bragg peak (SOBP) to within 1% on measured values for a variety of treatment fields relevant to ocular proton therapy. The MCNPX Monte Carlo transport code, in combination with realistic models for the ocular beam delivery apparatus and a water phantom, was used to calculate dose distributions and D/MU values, which were verified by the measurements. Measured proton beam data included central-axis depth dose profiles, relative cross-field profiles and absolute D/MU measurements under several combinations of beam penetration ranges and range-modulation widths. The Monte Carlo method predicted D/MU values that agreed with measurement to within 1% and dose profiles that agreed with measurement to within 3% of peak dose or within 0.5 mm distance-to-agreement. Lastly, a demonstration of the clinical utility of this technique included calculations of dose distributions and D/MU values in a realistic model of the human eye. It is possible to predict D/MU values accurately for clinical relevant range-modulated proton beams for ocular therapy using the Monte Carlo method. It is thus feasible to use the Monte Carlo method as a routine absolute dose algorithm for ocular proton therapy.

  18. Automatic planning of head and neck treatment plans

    DEFF Research Database (Denmark)

    Hazell, Irene; Bzdusek, Karl; Kumar, Prashant

    2016-01-01

    radiation dose planning (dosimetrist) and potentially improve the overall plan quality. This study evaluates the performance of the Auto-Planning module that has recently become clinically available in the Pinnacle3 radiation therapy treatment planning system. Twenty-six clinically delivered head and neck...... as the previously delivered clinical plans. For all patients, the Auto-Planning tool produced clinically acceptable head and neck treatment plans without any manual intervention, except for the initial target and OAR delineations. The main benefit of the method is the likely improvement in the overall treatment......Treatment planning is time-consuming and the outcome depends on the person performing the optimization. A system that automates treatment planning could potentially reduce the manual time required for optimization and could also pro-vide a method to reduce the variation between persons performing...

  19. A Monte Carlo tool for evaluating VMAT and DIMRT treatment deliveries including planar detectors

    International Nuclear Information System (INIS)

    Asuni, G; Van Beek, T A; Venkataraman, S; McCurdy, B M C; Popescu, I A

    2013-01-01

    The aim of this work is to describe and validate a new general research tool that performs Monte Carlo (MC) simulations for volumetric modulated arc therapy (VMAT) and dynamic intensity modulated radiation therapy (DIMRT), simultaneously tracking dose deposition in both the patient CT geometry and an arbitrary planar detector system. The tool is generalized to handle either entrance or exit detectors and provides the simulated dose for the individual control-points of the time-dependent VMAT and DIMRT deliveries. The MC simulation tool was developed with the EGSnrc radiation transport. For the individual control point simulation, we rotate the patient/phantom volume only (i.e. independent of the gantry and planar detector geometries) using the gantry angle in the treatment planning system (TPS) DICOM RP file such that each control point has its own unique phantom file. After MC simulation, we obtained the total dose to the phantom by summing dose contributions for all control points. Scored dose to the sensitive layer of the planar detector is available for each control point. To validate the tool, three clinical treatment plans were used including VMAT plans for a prostate case and a head-and-neck case, and a DIMRT plan for a head-and-neck case. An electronic portal imaging device operated in ‘movie’ mode was used with the VMAT plans delivered to cylindrical and anthropomorphic phantoms to validate the code using an exit detector. The DIMRT plan was delivered to a novel transmission detector, to validate the code using an entrance detector. The total MC 3D absolute doses in patient/phantom were compared with the TPS doses, while 2D MC doses were compared with planar detector doses for all individual control points, using the gamma evaluation test with 3%/3 mm criteria. The MC 3D absolute doses demonstrated excellent agreement with the TPS doses for all the tested plans, with about 95% of voxels having γ 90% of percentage pixels with γ <1. We found that over

  20. Computational Dosimetry and Treatment Planning Considerations for Neutron Capture Therapy

    International Nuclear Information System (INIS)

    Nigg, David Waler

    2003-01-01

    Specialized treatment planning software systems are generally required for neutron capture therapy (NCT) research and clinical applications. The standard simplifying approximations that work well for treatment planning computations in the case of many other modalities are usually not appropriate for application to neutron transport. One generally must obtain an explicit three-dimensional numerical solution of the governing transport equation, with energy-dependent neutron scattering completely taken into account. Treatment planning systems that have been successfully introduced for NCT applications over the past 15 years rely on the Monte Carlo stochastic simulation method for the necessary computations, primarily because of the geometric complexity of human anatomy. However, historically, there has also been interest in the application of deterministic methods, and there have been some practical developments in this area. Most recently, interest has turned toward the creation of treatment planning software that is not limited to any specific therapy modality, with NCT as only one of several applications. A key issue with NCT treatment planning has to do with boron quantification, and whether improved information concerning the spatial biodistribution of boron can be effectively used to improve the treatment planning process. Validation and benchmarking of computations for NCT are also of current developmental interest. Various institutions have their own procedures, but standard validation models are not yet in wide use

  1. Treatment planning optimization for linear accelerator radiosurgery

    International Nuclear Information System (INIS)

    Meeks, Sanford L.; Buatti, John M.; Bova, Francis J.; Friedman, William A.; Mendenhall, William M.

    1998-01-01

    Purpose: Linear accelerator radiosurgery uses multiple arcs delivered through circular collimators to produce a nominally spherical dose distribution. Production of dose distributions that conform to irregular lesions or conformally avoid critical neural structures requires a detailed understanding of the available treatment planning parameters. Methods and Materials: Treatment planning parameters that may be manipulated within a single isocenter to provide conformal avoidance and dose conformation to ellipsoidal lesions include differential arc weighting and gantry start/stop angles. More irregular lesions require the use of multiple isocenters. Iterative manipulation of treatment planning variables can be difficult and computationally expensive, especially if the effects of these manipulations are not well defined. Effects of treatment parameter manipulation are explained and illustrated. This is followed by description of the University of Florida Stereotactic Radiosurgery Treatment Planning Algorithm. This algorithm organizes the manipulations into a practical approach for radiosurgery treatment planning. Results: Iterative treatment planning parameters may be efficiently manipulated to achieve optimal treatment plans by following the University of Florida Treatment Planning Algorithm. The ability to produce conformal stereotactic treatment plans using the algorithm is demonstrated for a variety of clinical presentations. Conclusion: The standard dose distribution produced in linear accelerator radiosurgery is spherical, but manipulation of available treatment planning parameters may result in optimal dose conformation. The University of Florida Treatment Planning Algorithm organizes available treatment parameters to efficiently produce conformal radiosurgery treatment plans

  2. Planning, optimisation and evaluation of hyperthermia treatments

    NARCIS (Netherlands)

    Kok, H. P.; Kotte, A. N. T. J.; Crezee, J.

    2017-01-01

    Background: Hyperthermia treatment planning using dedicated simulations of power and temperature distributions is very useful to assist in hyperthermia applications. This paper describes an advanced treatment planning software package for a wide variety of applications. Methods: The in-house

  3. Treatment planning with ion beams

    International Nuclear Information System (INIS)

    Foss, M.H.

    1985-01-01

    Ions have higher linear energy transfer (LET) near the end of their range and lower LET away from the end of their range. Mixing radiations of different LET complicates treatment planning because radiation kills cells in two statistically independent ways. In some cases, cells are killed by a single-particle, which causes a linear decrease in log survival at low dosage. When the linear decrease is subtracted from the log survival curve, the remaining curve has zero slope at zero dosage. This curve is the log survival curve for cells that are killed only by two or more particles. These two mechanisms are statistically independent. To calculate survival, these two kinds of doses must be accumulated separately. The effect of each accumulated dosage must be read from its survival curve, and the logarithms of the two effects added to get the log survival. Treatment plans for doses of protons, He 3 ions, and He 4 ions suggest that these ions will be useful therapeutic modalities

  4. Treatment Plans for Antiproton Beams

    DEFF Research Database (Denmark)

    Holzscheiter, Michael; Bassler, Niels; Herrmann, Rochus

    from these measurements were used to benchmark the FLUKA Monte Carlo code, which then has been used for calculations of physical dose inside and outside of the primary antiproton beam. From clonogenic survival studies on the different cell lines mentioned above we have determined biological effective...

  5. Multi-period multi-objective electricity generation expansion planning problem with Monte-Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Tekiner, Hatice [Industrial Engineering, College of Engineering and Natural Sciences, Istanbul Sehir University, 2 Ahmet Bayman Rd, Istanbul (Turkey); Coit, David W. [Department of Industrial and Systems Engineering, Rutgers University, 96 Frelinghuysen Rd., Piscataway, NJ (United States); Felder, Frank A. [Edward J. Bloustein School of Planning and Public Policy, Rutgers University, Piscataway, NJ (United States)

    2010-12-15

    A new approach to the electricity generation expansion problem is proposed to minimize simultaneously multiple objectives, such as cost and air emissions, including CO{sub 2} and NO{sub x}, over a long term planning horizon. In this problem, system expansion decisions are made to select the type of power generation, such as coal, nuclear, wind, etc., where the new generation asset should be located, and at which time period expansion should take place. We are able to find a Pareto front for the multi-objective generation expansion planning problem that explicitly considers availability of the system components over the planning horizon and operational dispatching decisions. Monte-Carlo simulation is used to generate numerous scenarios based on the component availabilities and anticipated demand for energy. The problem is then formulated as a mixed integer linear program, and optimal solutions are found based on the simulated scenarios with a combined objective function considering the multiple problem objectives. The different objectives are combined using dimensionless weights and a Pareto front can be determined by varying these weights. The mathematical model is demonstrated on an example problem with interesting results indicating how expansion decisions vary depending on whether minimizing cost or minimizing greenhouse gas emissions or pollutants is given higher priority. (author)

  6. 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

  7. Model unspecific search in CMS. Treatment of insufficient Monte Carlo statistics

    Energy Technology Data Exchange (ETDEWEB)

    Lieb, Jonas; Albert, Andreas; Duchardt, Deborah; Hebbeker, Thomas; Knutzen, Simon; Meyer, Arnd; Pook, Tobias; Roemer, Jonas [III. Physikalisches Institut A, RWTH Aachen University (Germany)

    2016-07-01

    In 2015, the CMS detector recorded proton-proton collisions at an unprecedented center of mass energy of √(s)=13 TeV. The Model Unspecific Search in CMS (MUSiC) offers an analysis approach of these data which is complementary to dedicated analyses: By taking all produced final states into consideration, MUSiC is sensitive to indicators of new physics appearing in final states that are usually not investigated. In a two step process, MUSiC first classifies events according to their physics content and then searches kinematic distributions for the most significant deviations between Monte Carlo simulations and observed data. Such a general approach introduces its own set of challenges. One of them is the treatment of situations with insufficient Monte Carlo statistics. Complementing introductory presentations on the MUSiC event selection and classification, this talk will present a method of dealing with the issue of low Monte Carlo statistics.

  8. Treatment Planning for Ion Beam Therapy

    Science.gov (United States)

    Jäkel, Oliver

    The special aspects of treatment planning for ion beams are outlined in this chapter, starting with positioning and immobilization of the patient, describing imaging and segmentation, definition of treatment parameters, dose calculation and optimization, and, finally, plan assessment, verification, and quality assurance.

  9. Probability-neighbor method of accelerating geometry treatment in reactor Monte Carlo code RMC

    International Nuclear Information System (INIS)

    She, Ding; Li, Zeguang; Xu, Qi; Wang, Kan; Yu, Ganglin

    2011-01-01

    Probability neighbor method (PNM) is proposed in this paper to accelerate geometry treatment of Monte Carlo (MC) simulation and validated in self-developed reactor Monte Carlo code RMC. During MC simulation by either ray-tracking or delta-tracking method, large amounts of time are spent in finding out which cell one particle is located in. The traditional way is to search cells one by one with certain sequence defined previously. However, this procedure becomes very time-consuming when the system contains a large number of cells. Considering that particles have different probability to enter different cells, PNM method optimizes the searching sequence, i.e., the cells with larger probability are searched preferentially. The PNM method is implemented in RMC code and the numerical results show that the considerable time of geometry treatment in MC calculation for complicated systems is saved, especially effective in delta-tracking simulation. (author)

  10. Conformal three dimensional radiotherapy treatment planning in Lund

    International Nuclear Information System (INIS)

    Knoos, T.; Nilsson, P.; Anders, A.

    1995-01-01

    The use of conformal therapy is based on 3-dimensional treatment planning as well as on methods and routines for 3-dimensional patient mapping, 3-dimensional virtual simulation and others. The management of patients at the Radiotherapy Department at the University Hospital in Lund (Sweden) is discussed. About 2100 new patients are annually treated with external radiotherapy using seven linear accelerators. Three of the accelerators have dual photon energies and electron treatment facilities. A multi-leaf collimator as well as an electronic portal imaging device are available on one machine. Two simulators and an in-house CT-scanner are used for treatment planning. From 1988 to 1992 Scandiplan (Umplan) was used. Since 1992, the treatment planning system is TMS (HELAX AB, Sweden), which is based on the pencil beam algorithm of Ahnesjo. The calculations use patient modulated accelerator specific energy fluence spectra which are compiled with pencil beams from Monte Carlo generated energy absorption kernels. Heterogeneity corrections are performed with results close to conventional algorithms. Irregular fields, either from standard or individual blocks and from multi-leaf collimators are handled by the treatment planning system. The field shape is determined conveniently using the beam's eye view. The final field shape is exported electronically to either the block cutting machine or the multileaf collimator control computer. All patient fields are checked against the beam's eye view during simulation using manual methods. Treatment verification is performed by portal films and in vivo dosimetry with silicon diodes or TL-dosimetry. Up to now, approximately 4400 patients have received a highly individualized 3-dimensional conformal treatment

  11. Conformal three dimensional radiotherapy treatment planning in Lund

    Energy Technology Data Exchange (ETDEWEB)

    Knoos, T.; Nilsson, P. [Lund Univ. (Sweden). Dept. of Radiation Physics; Anders, A. [Lund Univ. (Sweden). Dept. of Oncology

    1995-12-01

    The use of conformal therapy is based on 3-dimensional treatment planning as well as on methods and routines for 3-dimensional patient mapping, 3-dimensional virtual simulation and others. The management of patients at the Radiotherapy Department at the University Hospital in Lund (Sweden) is discussed. About 2100 new patients are annually treated with external radiotherapy using seven linear accelerators. Three of the accelerators have dual photon energies and electron treatment facilities. A multi-leaf collimator as well as an electronic portal imaging device are available on one machine. Two simulators and an in-house CT-scanner are used for treatment planning. From 1988 to 1992 Scandiplan (Umplan) was used. Since 1992, the treatment planning system is TMS (HELAX AB, Sweden), which is based on the pencil beam algorithm of Ahnesjo. The calculations use patient modulated accelerator specific energy fluence spectra which are compiled with pencil beams from Monte Carlo generated energy absorption kernels. Heterogeneity corrections are performed with results close to conventional algorithms. Irregular fields, either from standard or individual blocks and from multi-leaf collimators are handled by the treatment planning system. The field shape is determined conveniently using the beam`s eye view. The final field shape is exported electronically to either the block cutting machine or the multileaf collimator control computer. All patient fields are checked against the beam`s eye view during simulation using manual methods. Treatment verification is performed by portal films and in vivo dosimetry with silicon diodes or TL-dosimetry. Up to now, approximately 4400 patients have received a highly individualized 3-dimensional conformal treatment.

  12. Concepts and Plans towards fast large scale Monte Carlo production for the ATLAS Experiment

    CERN Document Server

    Chapman, J; The ATLAS collaboration; Duehrssen, M; Elsing, M; Froidevaux, D; Harrington, R; Jansky, R; Langenberg, R; Mandrysch, R; Marshall, Z; Ritsch, E; Salzburger, A

    2013-01-01

    The huge success of Run 1 of the LHC for particle physics would not have been possible without detailed detector simulation of the experiments. However, the outstanding performance of the accelerator with a delivered luminosity of $L = 25 fb^{1}$ has created an unprecedented demand for Monte Carlo statistics. This has stretched the possibilities of the experiments due to the constraint of their computing infrastructure and available resources. Ensuring high quality Monte Carlo simulation samples with sufficient statistics became one the major focus points of experimental high energy physics and first analyses saw the advent of limitations in sensitivity or precision due to the lack of available Monte Carlo samples. Modern, concurrent computing techniques optimized for new processor hardware are being exploit to boost future computing resources, but even most optimistic scenarios predict that additional action needs to be taken to guarantee sufficient Monte Carlo production for high quality physics results dur...

  13. Computerized treatment planning systems for external photon beam radiotherapy

    International Nuclear Information System (INIS)

    Evans, M.D.C.

    2005-01-01

    simple 2-D models through 3-D models to 3-D Monte Carlo techniques, and increased computing power continues to increase calculation speed. Traditional forward based treatment planning, which is based on a trial and error approach by experienced professionals, is giving way to inverse planning, which makes use of dose optimization techniques to satisfy the user specified criteria for the dose to the target and critical structures. Dose optimization is possible by making use of dose-volume histograms (DVHs) based on CT, magnetic resonance imaging (MRI) or other digital imaging techniques. These optimized plans make use of intensity modulated radiotherapy (IMRT) to deliver the required dose to the target organ while respecting dose constraint criteria for critical organs. Computerized treatment planning is a rapidly evolving modality, relying heavily on both hardware and software. Thus it is necessary for related professionals to develop a workable quality assurance programme that reflects the use of the TPS in the clinic and that is sufficiently broad in scope to ensure proper treatment delivery

  14. Implant treatment planning: endodontic considerations.

    Science.gov (United States)

    Simonian, Krikor; Frydman, Alon; Verdugo, Fernando; Roges, Rafael; Kar, Kian

    2014-12-01

    Implants are a predictable and effective method for replacing missing teeth. Some clinicians have advocated extraction and replacement of compromised but treatable teeth on the assumption that implants will outperform endodontically and/or periodontally treated teeth. However, evidence shows that conventional therapy is as effective as implant treatment. With data on implants developing complications long term and a lack of predictable treatment for peri-implantitis, retaining and restoring the natural dentition should be the first choice when possible.

  15. Training Psychotherapists in Hierarchical Treatment Planning

    OpenAIRE

    MAKOVER, RICHARD B.

    1992-01-01

    Treatment planning is a central and persistent challenge in psychotherapy. This paper outlines a four-level planning hierarchy that encourages the therapist to conceptualize a desired overall outcome (the "aim") that can be realized through subsidiary objectives (the "goals"). The "strategies" by which goals are pursued and the "tactics" that carry out those strategies are subordinate and instrumental elements of the treatment process. Greater emphasis on this type of ...

  16. Pediatric radiotherapy planning and treatment

    CERN Document Server

    Olch, Arthur J

    2013-01-01

    "This is a very well-written and -organized book covering the planning and delivery aspects unique to pediatric radiotherapy. The author is a respected and well-known medical physicist with extensive pediatric radiotherapy experience. … a very useful book for any clinical physicist treating pediatric cases and seeking contextual and historical perspective. … a great reference for medical physicists who may not see many pediatric cases and can look to this text as a one-stop shop for not only a comprehensive overview, but detailed explanation for specific pediatric disease sites. Overall, it is a great addition to the reference library of any radiation therapy physicist."-Medical Physics, April 2014.

  17. When does treatment plan optimization require inverse planning?

    International Nuclear Information System (INIS)

    Sherouse, George W.

    1995-01-01

    Increasing maturity of image-based computer-aided design of three-dimensional conformal radiotherapy has recently sparked a great deal of work in the area of treatment plan optimization. Optimization of a conformal photon beam treatment plan is that exercise through which a set of intensity-modulated static beams or arcs is specified such that, when the plan is executed, 1) a region of homogeneous dose is produced in the patient with a shape which geometrically conforms (within a specified tolerance) to the three-dimensional shape of a designated target volume and 2) acceptably low incidental dose is delivered to non-target tissues. Interest in conformal radiotherapy arise from a fundamental assumption that there is significant value to be gained from aggressive customization of the treatment for each individual patient In our efforts to design optimal treatments, however, it is important to remember that, given the biological and economic realities of clinical radiotherapy, mathematical optimization of dose distribution metrics with respect to some minimal constraint set is not a necessary or even sufficient condition for design of a clinically optimal treatment. There is wide variation in the complexity of the clinical situations encountered in practice and there are a number of non-physical criteria to be considered in planning. There is also a complementary variety of computational and engineering means for achieving optimization. To date, the scientific dialogue regarding these techniques has concentrated on development of solutions to worst-case scenarios, largely in the absence of consideration of appropriate matching of solution complexity to problem complexity. It is the aim of this presentation to propose a provisional stratification of treatment planning problems, stratified by relative complexity, and to identify a corresponding stratification of necessary treatment planning techniques. It is asserted that the subset of clinical radiotherapy cases for

  18. Design and evaluation of a Monte Carlo based model of an orthovoltage treatment system

    International Nuclear Information System (INIS)

    Penchev, Petar; Maeder, Ulf; Fiebich, Martin; Zink, Klemens; University Hospital Marburg

    2015-01-01

    The aim of this study was to develop a flexible framework of an orthovoltage treatment system capable of calculating and visualizing dose distributions in different phantoms and CT datasets. The framework provides a complete set of various filters, applicators and X-ray energies and therefore can be adapted to varying studies or be used for educational purposes. A dedicated user friendly graphical interface was developed allowing for easy setup of the simulation parameters and visualization of the results. For the Monte Carlo simulations the EGSnrc Monte Carlo code package was used. Building the geometry was accomplished with the help of the EGSnrc C++ class library. The deposited dose was calculated according to the KERMA approximation using the track-length estimator. The validation against measurements showed a good agreement within 4-5% deviation, down to depths of 20% of the depth dose maximum. Furthermore, to show its capabilities, the validated model was used to calculate the dose distribution on two CT datasets. Typical Monte Carlo calculation time for these simulations was about 10 minutes achieving an average statistical uncertainty of 2% on a standard PC. However, this calculation time depends strongly on the used CT dataset, tube potential, filter material/thickness and applicator size.

  19. Monte Carlo techniques in radiation therapy

    CERN Document Server

    Verhaegen, Frank

    2013-01-01

    Modern cancer treatment relies on Monte Carlo simulations to help radiotherapists and clinical physicists better understand and compute radiation dose from imaging devices as well as exploit four-dimensional imaging data. With Monte Carlo-based treatment planning tools now available from commercial vendors, a complete transition to Monte Carlo-based dose calculation methods in radiotherapy could likely take place in the next decade. Monte Carlo Techniques in Radiation Therapy explores the use of Monte Carlo methods for modeling various features of internal and external radiation sources, including light ion beams. The book-the first of its kind-addresses applications of the Monte Carlo particle transport simulation technique in radiation therapy, mainly focusing on external beam radiotherapy and brachytherapy. It presents the mathematical and technical aspects of the methods in particle transport simulations. The book also discusses the modeling of medical linacs and other irradiation devices; issues specific...

  20. A new approach for radiosynoviorthesis: A dose-optimized planning method based on Monte Carlo simulation and synovial measurement using 3D slicer and MRI.

    Science.gov (United States)

    Torres Berdeguez, Mirta Bárbara; Thomas, Sylvia; Rafful, Patricia; Arruda Sanchez, Tiago; Medeiros Oliveira Ramos, Susie; Souza Albernaz, Marta; Vasconcellos de Sá, Lidia; Lopes de Souza, Sergio Augusto; Mas Milian, Felix; Silva, Ademir Xavier da

    2017-07-01

    Recently, there has been a growing interest in a methodology for dose planning in radiosynoviorthesis to substitute fixed activity. Clinical practice based on fixed activity frequently does not embrace radiopharmaceutical dose optimization in patients. The aim of this paper is to propose and discuss a dose planning methodology considering the radiological findings of interest obtained by three-dimensional magnetic resonance imaging combined with Monte Carlo simulation in radiosynoviorthesis treatment applied to hemophilic arthropathy. The parameters analyzed were: surface area of the synovial membrane (synovial size), synovial thickness and joint effusion obtained by 3D MRI of nine knees from nine patients on a SIEMENS AVANTO 1.5 T scanner using a knee coil. The 3D Slicer software performed both the semiautomatic segmentation and quantitation of these radiological findings. A Lucite phantom 3D MRI validated the quantitation methodology. The study used Monte Carlo N-Particle eXtended code version 2.6 for calculating the S-values required to set up the injected activity to deliver a 100 Gy absorbed dose at a determined synovial thickness. The radionuclides assessed were: 90Y, 32P, 188Re, 186Re, 153Sm, and 177Lu, and the present study shows their effective treatment ranges. The quantitation methodology was successfully tested, with an error below 5% for different materials. S-values calculated could provide data on the activity to be injected into the joint, considering no extra-articular leakage from joint cavity. Calculation of effective treatment range could assist with the therapeutic decision, with an optimized protocol for dose prescription in RSO. Using 3D Slicer software, this study focused on segmentation and quantitation of radiological features such as joint effusion, synovial size, and thickness, all obtained by 3D MRI in patients' knees with hemophilic arthropathy. The combination of synovial size and thickness with the parameters obtained by Monte Carlo

  1. Method of radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Hodes, L.

    1976-01-01

    A technique of radiation therapy treatment planning designed to allow the assignment of dosage limits directly to chosen points in the computer-displayed cross-section of the patient. These dosage limits are used as constraints in a linear programming attempt to solve for beam strengths, minimizing integral dosage. If a feasible plan exists, the optimized plan will be displayed for approval as an isodose pattern. If there is no feasible plan, the operator/therapist can designate some of the point dosage constraints as ''relaxed.'' Linear programming will then optimize for minimum deviation at the relaxed points. This process can be iterated and new points selected until an acceptable plan is realized. In this manner the plan is optimized for uniformity as well as overall low dosage. 6 claims, 6 drawing figures

  2. Emergency Planning for Municipal Wastewater Treatment Facilities.

    Science.gov (United States)

    Lemon, R. A.; And Others

    This manual for the development of emergency operating plans for municipal wastewater treatment systems was compiled using information provided by over two hundred municipal treatment systems. It covers emergencies caused by natural disasters, civil disorders and strikes, faulty maintenance, negligent operation, and accidents. The effects of such…

  3. A comparison of forward and inverse treatment planning for intensity-modulated radiotherapy of head and neck cancer

    International Nuclear Information System (INIS)

    Baer, Werner; Schwarz, Marco; Alber, Markus; Bos, Luc J.; Mijnheer, Ben J.; Rasch, Coen; Schneider, Christoph; Nuesslin, Fridtjof; Damen, Eugene M.F.

    2003-01-01

    Background and purpose: To compare intensity-modulated treatment plans of patients with head and neck cancer generated by forward and inverse planning. Materials and methods: Ten intensity-modulated treatment plans, planned and treated with a step and shoot technique using a forward planning approach, were retrospectively re-planned with an inverse planning algorithm. For this purpose, two strategies were applied. First, inverse planning was performed with the same beam directions as forward planning. In addition, nine equidistant, coplanar incidences were used. The main objective of the optimisation process was the sparing of the parotid glands beside an adequate treatment of the planning target volume (PTV). Inverse planning was performed both with pencil beam and Monte Carlo dose computation to investigate the influence of dose computation on the result of the optimisation. Results: In most cases, both inverse planning strategies managed to improve the treatment plans distinctly due to a better target coverage, a better sparing of the parotid glands or both. A reduction of the mean dose by 3-11 Gy for at least one of the parotid glands could be achieved for most of the patients. For three patients, inverse planning allowed to spare a parotid gland that had to be sacrificed by forward planning. Inverse planning increased the number of segments compared to forward planning by a factor of about 3; from 9-15 to 27-46. No significant differences for PTV and parotid glands between both inverse planning approaches were found. Also, the use of Monte Carlo instead of pencil beam dose computation did not influence the results significantly. Conclusion: The results demonstrate the potential of inverse planning to improve intensity-modulated treatment plans for head and neck cases compared to forward planning while retaining clinical utility in terms of treatment time and quality assurance

  4. [Planning guidelines for prosthodontic treatment].

    Science.gov (United States)

    Shiga, Hiroshi; Terada, Yoshihiro; Shinya, Akiyoshi; Ikebe, Kazunori; Tamazawa, Yoshinori; Nagadome, Hatsumi; Akagawa, Yasumasa

    2008-01-01

    In recent years "practice guidelines" based on EBM techniques have even been attracting attention at a societal level, and guidelines modeled after the procedure for preparing practice guideline (described at http://www.niph.go.jp/glgl-4.3rev.htm) have begun to be drafted and made public. With the aim of ensuring the quality and presenting the basic concepts of prosthodontic therapy, the Japan Prosthodontic Society, which bears a great obligation and responsibility toward society and the Japanese public, has decided to undertake the formulation of guidelines related to prosthodontic therapy, and decided to first undertake the formulation of "Practice guideline for denture relining and rebasing", and to prepare a guideline model. We tried to prepare the guidelines according to the "Procedure for preparing practice guidelines", but because of the scientific uniqueness of prosthodontic treatment and dentistry, research to elucidate the basis of treatment has been insufficient, and we ultimately reconfirmed the current state of affairs in which it is difficult to perform. We therefore prepared the guidelines based on the limited evidence obtained in a search of the scientific literature and on the consensus of experts. The Japan Prosthodontic Society has investigated and prepared a Society guideline "model" to the extent possible at the present time, and it has prepared "Guidelines for adhesion bridge" and "Practice guidelines for denture prosthodontics" based on it. Nevertheless, the fact of the matter is that we are faced with numerous problems, and we think that in the future new bases and clinical knowledge will be accumulated by promoting scientific clinical research, and that the guidelines should be revised regularly based on them.

  5. Monte-Carlo treatment of nonlinear collisional effects in charged-particle transport

    International Nuclear Information System (INIS)

    Weiss, D.L.; Witte, K.H.; Sheppard, M.G.; Oliphant, T.A.

    1985-01-01

    The effects of two-body coulomb collisions of the simulation particles against a background material are often treated by a Monte-Carlo collisional process in which the collision probability is determined by a Fokker-Planck treatment. This procedure is nonlinear if the properties of the background material are allowed to change as a result of the scattering of the simulation particles. A more completely, nonlinear problem is obtained if the simulation particles themselves form all or part of the background distribution. A new method is presented here for doing this, and examples will be discussed that illustrate the power of the technique

  6. Tolerance doses for treatment planning

    International Nuclear Information System (INIS)

    Lyman, J.T.

    1985-10-01

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD 5 ) or 50% (TD 50 ) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs

  7. Tolerance doses for treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Lyman, J.T.

    1985-10-01

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD/sub 5/) or 50% (TD/sub 50/) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs.

  8. Improving treatment plan evaluation with automation

    Science.gov (United States)

    Covington, Elizabeth L.; Chen, Xiaoping; Younge, Kelly C.; Lee, Choonik; Matuszak, Martha M.; Kessler, Marc L.; Keranen, Wayne; Acosta, Eduardo; Dougherty, Ashley M.; Filpansick, Stephanie E.

    2016-01-01

    The goal of this work is to evaluate the effectiveness of Plan‐Checker Tool (PCT) which was created to improve first‐time plan quality, reduce patient delays, increase the efficiency of our electronic workflow, and standardize and automate the physics plan review in the treatment planning system (TPS). PCT uses an application programming interface to check and compare data from the TPS and treatment management system (TMS). PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user as part of a plan readiness check for treatment. Prior to and during PCT development, errors identified during the physics review and causes of patient treatment start delays were tracked to prioritize which checks should be automated. Nineteen of 33 checklist items were automated, with data extracted with PCT. There was a 60% reduction in the number of patient delays in the six months after PCT release. PCT was successfully implemented for use on all external beam treatment plans in our clinic. While the number of errors found during the physics check did not decrease, automation of checks increased visibility of errors during the physics check, which led to decreased patient delays. The methods used here can be applied to any TMS and TPS that allows queries of the database. PACS number(s): 87.55.‐x, 87.55.N‐, 87.55.Qr, 87.55.tm, 89.20.Bb PMID:27929478

  9. Fuzzy logic guided inverse treatment planning

    International Nuclear Information System (INIS)

    Yan Hui; Yin Fangfang; Guan Huaiqun; Kim, Jae Ho

    2003-01-01

    A fuzzy logic technique was applied to optimize the weighting factors in the objective function of an inverse treatment planning system for intensity-modulated radiation therapy (IMRT). Based on this technique, the optimization of weighting factors is guided by the fuzzy rules while the intensity spectrum is optimized by a fast-monotonic-descent method. The resultant fuzzy logic guided inverse planning system is capable of finding the optimal combination of weighting factors for different anatomical structures involved in treatment planning. This system was tested using one simulated (but clinically relevant) case and one clinical case. The results indicate that the optimal balance between the target dose and the critical organ dose is achieved by a refined combination of weighting factors. With the help of fuzzy inference, the efficiency and effectiveness of inverse planning for IMRT are substantially improved

  10. Three-dimensional teletherapy treatment planning

    International Nuclear Information System (INIS)

    Panthaleon van Eck, R.B. van.

    1986-01-01

    This thesis deals with physical/mathematical backgrounds of computerized teletherapy treatment planning. The subjects discussed in this thesis can be subdivided into three main categories: a) Three-dimensional treatment planning. A method is evaluated which can be used for the purpose of simulation and optimization of dose distributions in three dimensions. b) The use of Computed Tomography. The use of patient information obtained from Computed Tomography for the purpose of dose computations is evaluated. c) Dose computational models for photon- and electron beams. Models are evaluated which provide information regarding the way in which the radiation dose is distributed in the patient (viz. is absorbed and/or dispersed). (Auth.)

  11. Comparison of absorbed dose in the cervix carcinoma therapy by brachytherapy of high dose rate using the conventional planning and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Silva, Aneli Oliveira da

    2010-01-01

    This study aims to compare the doses received for patients submitted to brachytherapy High Dose Rate (HDR) brachytherapy, a method of treatment of the cervix carcinoma, performed in the planning system PLATO BPS with the doses obtained by Monte Carlo simulation using the radiation transport code MCNP 5 and one female anthropomorphic phantom based on voxel, the FAX. The implementation of HDR brachytherapy treatment for the cervix carcinoma consists of the insertion of an intrauterine probe and an intravaginal probe (ring or ovoid) and then two radiographs are obtained, anteroposterior (AP) and lateral (LAT) to confirm the position of the applicators in the patient and to allow the treatment planning and the determination of the absorbed dose at points of interest: rectum, bladder, sigmoid and point A, which corresponds anatomically to the crossings of the uterine arteries with ureters The absorbed doses obtained with the code MCNP 5, with the exception of the absorbed dose in the rectum and sigmoid for the simulation considering a point source of 192 Ir, are lower than the absorbed doses from PLATO BPS calculations because the MCNP 5 considers the chemical compositions and densities of FAX body, not considering the medium as water. When considering the Monte Carlo simulation for a source with dimensions equal to that used in the brachytherapy irradiator used in this study, the values of calculated absorbed dose to the bladder, to the rectum, to the right point A and to the left point A were respectively lower than those determined by the treatment planning system in 33.29, 5.01, 22.93 and 19.04%. These values are almost all larger than the maximum acceptable deviation between patient planned and administered doses (5 %). With regard to the rectum and bladder, which are organs that must be protected, the present results are in favor of the radiological protection of patients. The point A, that is on the isodose of 100%, used to tumor treatment, the results indicate

  12. SU-D-BRD-01: Cloud-Based Radiation Treatment Planning: Performance Evaluation of Dose Calculation and Plan Optimization

    International Nuclear Information System (INIS)

    Na, Y; Kapp, D; Kim, Y; Xing, L; Suh, T

    2014-01-01

    Purpose: To report the first experience on the development of a cloud-based treatment planning system and investigate the performance improvement of dose calculation and treatment plan optimization of the cloud computing platform. Methods: A cloud computing-based radiation treatment planning system (cc-TPS) was developed for clinical treatment planning. Three de-identified clinical head and neck, lung, and prostate cases were used to evaluate the cloud computing platform. The de-identified clinical data were encrypted with 256-bit Advanced Encryption Standard (AES) algorithm. VMAT and IMRT plans were generated for the three de-identified clinical cases to determine the quality of the treatment plans and computational efficiency. All plans generated from the cc-TPS were compared to those obtained with the PC-based TPS (pc-TPS). The performance evaluation of the cc-TPS was quantified as the speedup factors for Monte Carlo (MC) dose calculations and large-scale plan optimizations, as well as the performance ratios (PRs) of the amount of performance improvement compared to the pc-TPS. Results: Speedup factors were improved up to 14.0-fold dependent on the clinical cases and plan types. The computation times for VMAT and IMRT plans with the cc-TPS were reduced by 91.1% and 89.4%, respectively, on average of the clinical cases compared to those with pc-TPS. The PRs were mostly better for VMAT plans (1.0 ≤ PRs ≤ 10.6 for the head and neck case, 1.2 ≤ PRs ≤ 13.3 for lung case, and 1.0 ≤ PRs ≤ 10.3 for prostate cancer cases) than for IMRT plans. The isodose curves of plans on both cc-TPS and pc-TPS were identical for each of the clinical cases. Conclusion: A cloud-based treatment planning has been setup and our results demonstrate the computation efficiency of treatment planning with the cc-TPS can be dramatically improved while maintaining the same plan quality to that obtained with the pc-TPS. This work was supported in part by the National Cancer Institute (1

  13. Radiotherapy treatment planning linear-quadratic radiobiology

    CERN Document Server

    Chapman, J Donald

    2015-01-01

    Understand Quantitative Radiobiology from a Radiation Biophysics PerspectiveIn the field of radiobiology, the linear-quadratic (LQ) equation has become the standard for defining radiation-induced cell killing. Radiotherapy Treatment Planning: Linear-Quadratic Radiobiology describes tumor cell inactivation from a radiation physics perspective and offers appropriate LQ parameters for modeling tumor and normal tissue responses.Explore the Latest Cell Killing Numbers for Defining Iso-Effective Cancer TreatmentsThe book compil

  14. Dosimetry treatment planning with uncertainty evaluation

    International Nuclear Information System (INIS)

    Henriquez, Francisco Cutanda; Castrillyn, Silvia Vargas

    2010-01-01

    Treatment planning results can be presented as a dosimetry report, consisting of a number of images, curves, indices, etc. and in a prescription for the delivery of the planned treatment. A complex decision process is needed in order to decide which the optimal plan is. Since this decision is based on dose computations with their associated uncertainty, a modern treatment planning process has to deal with the effects of uncertainty to achieve maximum accuracy. Several tools are presented allowing the user to work with uncertainty. Modified dose volume histograms can help evaluate competing plans so that a proper hierarchy can be established amongst different goals. Material/Methods: A central estimate of a dose volume histogram curve and two limit curves define an 'indifference' band in the dose volume plane. Every plan within this band can be considered not better than the initial one, because uncertainty does not allow telling them apart. If a DVH goal is met within the indifference band, the user can aim to improve a different goal. Results: The methods proposed in this work are easily introduced in clinical practice. They are compatible with an iterative optimization process adding few steps to the computation. Conclusion: Accuracy requirements in radiation therapy keep on increasing, while accuracy in dose measurement or modeling is only moderately improving. Although it is a minor part in the overall uncertainty budget for the treatment, computation uncertainty affects decision making. Our method help make decisions with a maximum of information. This novel method can also provide quantitative measures of the probability of achieving the goals.(Author)

  15. Optimal caliper width for propensity score matching of three treatment groups: a Monte Carlo study.

    Science.gov (United States)

    Wang, Yongji; Cai, Hongwei; Li, Chanjuan; Jiang, Zhiwei; Wang, Ling; Song, Jiugang; Xia, Jielai

    2013-01-01

    Propensity score matching is a method to reduce bias in non-randomized and observational studies. Propensity score matching is mainly applied to two treatment groups rather than multiple treatment groups, because some key issues affecting its application to multiple treatment groups remain unsolved, such as the matching distance, the assessment of balance in baseline variables, and the choice of optimal caliper width. The primary objective of this study was to compare propensity score matching methods using different calipers and to choose the optimal caliper width for use with three treatment groups. The authors used caliper widths from 0.1 to 0.8 of the pooled standard deviation of the logit of the propensity score, in increments of 0.1. The balance in baseline variables was assessed by standardized difference. The matching ratio, relative bias, and mean squared error (MSE) of the estimate between groups in different propensity score-matched samples were also reported. The results of Monte Carlo simulations indicate that matching using a caliper width of 0.2 of the pooled standard deviation of the logit of the propensity score affords superior performance in the estimation of treatment effects. This study provides practical solutions for the application of propensity score matching of three treatment groups.

  16. Automated radiotherapy treatment plan integrity verification

    International Nuclear Information System (INIS)

    Yang Deshan; Moore, Kevin L.

    2012-01-01

    Purpose: In our clinic, physicists spend from 15 to 60 min to verify the physical and dosimetric integrity of radiotherapy plans before presentation to radiation oncology physicians for approval. The purpose of this study was to design and implement a framework to automate as many elements of this quality control (QC) step as possible. Methods: A comprehensive computer application was developed to carry out a majority of these verification tasks in the Philips PINNACLE treatment planning system (TPS). This QC tool functions based on both PINNACLE scripting elements and PERL sub-routines. The core of this technique is the method of dynamic scripting, which involves a PERL programming module that is flexible and powerful for treatment plan data handling. Run-time plan data are collected, saved into temporary files, and analyzed against standard values and predefined logical rules. The results were summarized in a hypertext markup language (HTML) report that is displayed to the user. Results: This tool has been in clinical use for over a year. The occurrence frequency of technical problems, which would cause delays and suboptimal plans, has been reduced since clinical implementation. Conclusions: In addition to drastically reducing the set of human-driven logical comparisons, this QC tool also accomplished some tasks that are otherwise either quite laborious or impractical for humans to verify, e.g., identifying conflicts amongst IMRT optimization objectives.

  17. Automatic treatment planning facilitates fast generation of high-quality treatment plans for esophageal cancer.

    Science.gov (United States)

    Hansen, Christian Rønn; Nielsen, Morten; Bertelsen, Anders Smedegaard; Hazell, Irene; Holtved, Eva; Zukauskaite, Ruta; Bjerregaard, Jon Kroll; Brink, Carsten; Bernchou, Uffe

    2017-11-01

    The quality of radiotherapy planning has improved substantially in the last decade with the introduction of intensity modulated radiotherapy. The purpose of this study was to analyze the plan quality and efficacy of automatically (AU) generated VMAT plans for inoperable esophageal cancer patients. Thirty-two consecutive inoperable patients with esophageal cancer originally treated with manually (MA) generated volumetric modulated arc therapy (VMAT) plans were retrospectively replanned using an auto-planning engine. All plans were optimized with one full 6MV VMAT arc giving 60 Gy to the primary target and 50 Gy to the elective target. The planning techniques were blinded before clinical evaluation by three specialized oncologists. To supplement the clinical evaluation, the optimization time for the AU plan was recorded along with DVH parameters for all plans. Upon clinical evaluation, the AU plan was preferred for 31/32 patients, and for one patient, there was no difference in the plans. In terms of DVH parameters, similar target coverage was obtained between the two planning methods. The mean dose for the spinal cord increased by 1.8 Gy using AU (p = .002), whereas the mean lung dose decreased by 1.9 Gy (p plans were more modulated as seen by the increase of 12% in mean MUs (p = .001). The median optimization time for AU plans was 117 min. The AU plans were in general preferred and showed a lower mean dose to the lungs. The automation of the planning process generated esophageal cancer treatment plans quickly and with high quality.

  18. SU-F-T-377: Monte Carlo Re-Evaluation of Volumetric-Modulated Arc Plans of Advanced Stage Nasopharygeal Cancers Optimized with Convolution-Superposition Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K; Leung, R; Law, G; Wong, M; Lee, V; Tung, S; Cheung, S; Chan, M [Tuen Mun Hospital, Hong Kong (Hong Kong)

    2016-06-15

    Background: Commercial treatment planning system Pinnacle3 (Philips, Fitchburg, WI, USA) employs a convolution-superposition algorithm for volumetric-modulated arc radiotherapy (VMAT) optimization and dose calculation. Study of Monte Carlo (MC) dose recalculation of VMAT plans for advanced-stage nasopharyngeal cancers (NPC) is currently limited. Methods: Twenty-nine VMAT prescribed 70Gy, 60Gy, and 54Gy to the planning target volumes (PTVs) were included. These clinical plans achieved with a CS dose engine on Pinnacle3 v9.0 were recalculated by the Monaco TPS v5.0 (Elekta, Maryland Heights, MO, USA) with a XVMC-based MC dose engine. The MC virtual source model was built using the same measurement beam dataset as for the Pinnacle beam model. All MC recalculation were based on absorbed dose to medium in medium (Dm,m). Differences in dose constraint parameters per our institution protocol (Supplementary Table 1) were analyzed. Results: Only differences in maximum dose to left brachial plexus, left temporal lobe and PTV54Gy were found to be statistically insignificant (p> 0.05). Dosimetric differences of other tumor targets and normal organs are found in supplementary Table 1. Generally, doses outside the PTV in the normal organs are lower with MC than with CS. This is also true in the PTV54-70Gy doses but higher dose in the nasal cavity near the bone interfaces is consistently predicted by MC, possibly due to the increased backscattering of short-range scattered photons and the secondary electrons that is not properly modeled by the CS. The straight shoulders of the PTV dose volume histograms (DVH) initially resulted from the CS optimization are merely preserved after MC recalculation. Conclusion: Significant dosimetric differences in VMAT NPC plans were observed between CS and MC calculations. Adjustments of the planning dose constraints to incorporate the physics differences from conventional CS algorithm should be made when VMAT optimization is carried out directly

  19. Knowledge-based treatment planning and its potential role in the transition between treatment planning systems.

    Science.gov (United States)

    Masi, Kathryn; Archer, Paul; Jackson, William; Sun, Yilun; Schipper, Matthew; Hamstra, Daniel; Matuszak, Martha

    2017-11-22

    Commissioning a new treatment planning system (TPS) involves many time-consuming tasks. We investigated the role that knowledge-based planning (KBP) can play in aiding a clinic's transition to a new TPS. Sixty clinically treated prostate/prostate bed intensity-modulated radiation therapy (IMRT) plans were exported from an in-house TPS and were used to create a KBP model in a newly implemented commercial application. To determine the benefit that KBP may have in a TPS transition, the model was tested on 2 groups of patients. Group 1 consisted of the first 10 prostate/prostate bed patients treated in the commercial TPS after the transition from the in-house TPS. Group 2 consisted of 10 patients planned in the commercial TPS after 8 months of clinical use. The KBP-generated plan was compared with the clinically used plan in terms of plan quality (ability to meet planning objectives and overall dose metrics) and planning efficiency (time required to generate clinically acceptable plans). The KBP-generated plans provided a significantly improved target coverage (p = 0.01) compared with the clinically used plans for Group 1, but yielded plans of comparable target coverage to the clinically used plans for Group 2. For the organs at risk, the KBP-generated plans produced lower doses, on average, for every normal-tissue objective except for the maximum dose to 0.1 cc of rectum. The time needed for the KBP-generated plans ranged from 6 to 15 minutes compared to 30 to 150 and 15 to 60 minutes for manual planning in Groups 1 and 2, respectively. KBP is a promising tool to aid in the transition to a new TPS. Our study indicates that high-quality treatment plans could have been generated in the newly implemented TPS more efficiently compared with not using KBP. Even after 8 months of the clinical use, KBP still showed an increase in plan quality and planning efficiency compared with manual planning. Copyright © 2017 American Association of Medical Dosimetrists. Published

  20. Collision detection and avoidance during treatment planning

    International Nuclear Information System (INIS)

    Humm, John L.; Pizzuto, Domenico; Fleischman, Eric; Mohan, Radhe

    1995-01-01

    Purpose: To develop computer software that assists the planner avoid potential gantry collisions with the patient or patient support assembly during the treatment planning process. Methods and Materials: The approach uses a simulation of the therapy room with a scale model of the treatment machine. Because the dimensions of the machine and patient are known, one can calculate a priori whether any desired therapy field is possible or will result in a collision. To assist the planner, we have developed a graphical interface enabling the accurate visualization of each treatment field configuration with a 'room's eye view' treatment planning window. This enables the planner to be aware of, and alleviate any potential collision hazards. To circumvent blind spots in the graphic representation, an analytical software module precomputes whether each update of the gantry or turntable position is safe. Results: If a collision is detected, the module alerts the planner and suggests collision evasive actions such as either an extended distance treatment or the gantry angle of closest approach. Conclusions: The model enables the planner to experiment with unconventional noncoplanar treatment fields, and immediately test their feasibility

  1. Automatic liver contouring for radiotherapy treatment planning

    Science.gov (United States)

    Li, Dengwang; Liu, Li; Kapp, Daniel S.; Xing, Lei

    2015-09-01

    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

  2. Computer-assisted treatment planning and analysis.

    Science.gov (United States)

    Beers, A C; Choi, W; Pavlovskaia, E

    2003-01-01

    The Invisalign orthodontic system (Align Technology, Inc, Santa Clara, CA) is a series of clear removable appliances that is worn by a patient to correct malocclusions. Introduced in 1999, it has been applied to successfully correct an increasingly wide variety of malocclusions. Part of the success of the system is because of the innovative technologies inherent in the design of the appliances. During the development of the system, many challenges and issues needed to be overcome to realize the product. Many of these issues were not specific to Invisalign, and represented general problems in the area of computer-aided orthodontics. The general problems of developing a virtual model of a patient's dentition appropriate for use in orthodontics, performing a treatment plan on a virtual dentition model, and analyzing how accurately the virtual treatment plan executed in the patient's mouth are presented.

  3. Electron Density Calibration for Radiotherapy Treatment Planning

    International Nuclear Information System (INIS)

    Herrera-Martinez, F.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Ruiz-Trejo, C.; Celis-Lopez, M. A.; Larraga-Gutierrez, J. M.; Garcia-Garduno, A.

    2006-01-01

    Computed tomography (CT) images are used as basic input data for most modern radiosurgery treatment planning systems (TPS). CT data not only provide anatomic information to delineate target volumes, but also allow the introduction of corrections for tissue inhomogeneities into dose calculations during the treatment planning procedure. These corrections involve the determination of a relationship between tissue electron density (ρe) and their corresponding Hounsfield Units (HU). In this work, an elemental analysis of different commercial tissue equivalent materials using Scanning Electron Microscopy was carried out to characterize their chemical composition. The tissue equivalent materials were chosen to ensure a large range of ρe to be included in the CT scanner calibration. A phantom was designed and constructed with these materials to simulate the size of a human head

  4. The Monte Carlo srna code as the engine in istar proton dose planning software for the tesla accelerator installation

    Directory of Open Access Journals (Sweden)

    Ilić Radovan D.

    2004-01-01

    Full Text Available This paper describes the application of SRNA Monte Carlo package for proton transport simulations in complex geometry and different material composition. SRNA package was developed for 3D dose distribution calculation in proton therapy and dosimetry and it was based on the theory of multiple scattering. The compound nuclei decay was simulated by our own and the Russian MSDM models using ICRU 63 data. The developed package consists of two codes SRNA-2KG, which simulates proton transport in the combinatorial geometry and SRNA-VOX, which uses the voxelized geometry using the CT data and conversion of the Hounsfield’s data to tissue elemental composition. Transition probabilities for both codes are prepared by the SRNADAT code. The simulation of proton beam characterization by Multi-Layer Faraday Cup, spatial distribution of positron emitters obtained by SRNA-2KG code, and intercomparison of computational codes in radiation dosimetry, indicate the immediate application of the Monte Carlo techniques in clinical practice. In this paper, we briefly present the physical model implemented in SRNA pack age, the ISTAR proton dose planning software, as well as the results of the numerical experiments with proton beams to obtain 3D dose distribution in the eye and breast tumor.

  5. Clinical trial optimization: Monte Carlo simulation Markov model for planning clinical trials recruitment.

    Science.gov (United States)

    Abbas, Ismail; Rovira, Joan; Casanovas, Josep

    2007-05-01

    The patient recruitment process of clinical trials is an essential element which needs to be designed properly. In this paper we describe different simulation models under continuous and discrete time assumptions for the design of recruitment in clinical trials. The results of hypothetical examples of clinical trial recruitments are presented. The recruitment time is calculated and the number of recruited patients is quantified for a given time and probability of recruitment. The expected delay and the effective recruitment durations are estimated using both continuous and discrete time modeling. The proposed type of Monte Carlo simulation Markov models will enable optimization of the recruitment process and the estimation and the calibration of its parameters to aid the proposed clinical trials. A continuous time simulation may minimize the duration of the recruitment and, consequently, the total duration of the trial.

  6. Three-dimensional radiation treatment planning

    International Nuclear Information System (INIS)

    Mohan, R.

    1989-01-01

    A major aim of radiation therapy is to deliver sufficient dose to the tumour volume to kill the cancer cells while sparing the nearby health organs to prevent complications. With the introduction of devices such as CT and MR scanners, radiation therapy treatment planners have access to full three-dimensional anatomical information to define, simulate, and evaluate treatments. There are a limited number of prototype software systems that allow 3D treatment planning currently in use. In addition, there are more advanced tools under development or still in the planning stages. They require sophisticated graphics and computation equipment, complex physical and mathematical algorithms, and new radiation treatment machines that deliver dose very precisely under computer control. Components of these systems include programs for the identification and delineation of the anatomy and tumour, the definition of radiation beams, the calculation of dose distribution patterns, the display of dose on 2D images and as three dimensional surfaces, and the generation of computer images to verify proper patient positioning in treatment. Some of these functions can be performed more quickly and accurately if artificial intelligence or expert systems techniques are employed. 28 refs., figs

  7. Real-time interactive treatment planning

    International Nuclear Information System (INIS)

    Otto, Karl

    2014-01-01

    The goal of this work is to develop an interactive treatment planning platform that permits real-time manipulation of dose distributions including DVHs and other dose metrics. The hypothesis underlying the approach proposed here is that the process of evaluating potential dose distribution options and deciding on the best clinical trade-offs may be separated from the derivation of the actual delivery parameters used for the patient’s treatment. For this purpose a novel algorithm for deriving an Achievable Dose Estimate (ADE) was developed. The ADE algorithm is computationally efficient so as to update dose distributions in effectively real-time while accurately incorporating the limits of what can be achieved in practice. The resulting system is a software environment for interactive real-time manipulation of dose that permits the clinician to rapidly develop a fully customized 3D dose distribution. Graphical navigation of dose distributions is achieved by a sophisticated method of identifying contributing fluence elements, modifying those elements and re-computing the entire dose distribution. 3D dose distributions are calculated in ∼2–20 ms. Including graphics processing overhead, clinicians may visually interact with the dose distribution (e.g. ‘drag’ a DVH) and display updates of the dose distribution at a rate of more than 20 times per second. Preliminary testing on various sites shows that interactive planning may be completed in ∼1–5 min, depending on the complexity of the case (number of targets and OARs). Final DVHs are derived through a separate plan optimization step using a conventional VMAT planning system and were shown to be achievable within 2% and 4% in high and low dose regions respectively. With real-time interactive planning trade-offs between Target(s) and OARs may be evaluated efficiently providing a better understanding of the dosimetric options available to each patient in static or adaptive RT. (paper)

  8. Conventional treatment planning optimization using simulated annealing

    International Nuclear Information System (INIS)

    Morrill, S.M.; Langer, M.; Lane, R.G.

    1995-01-01

    Purpose: Simulated annealing (SA) allows for the implementation of realistic biological and clinical cost functions into treatment plan optimization. However, a drawback to the clinical implementation of SA optimization is that large numbers of beams appear in the final solution, some with insignificant weights, preventing the delivery of these optimized plans using conventional (limited to a few coplanar beams) radiation therapy. A preliminary study suggested two promising algorithms for restricting the number of beam weights. The purpose of this investigation was to compare these two algorithms using our current SA algorithm with the aim of producing a algorithm to allow clinically useful radiation therapy treatment planning optimization. Method: Our current SA algorithm, Variable Stepsize Generalized Simulated Annealing (VSGSA) was modified with two algorithms to restrict the number of beam weights in the final solution. The first algorithm selected combinations of a fixed number of beams from the complete solution space at each iterative step of the optimization process. The second reduced the allowed number of beams by a factor of two at periodic steps during the optimization process until only the specified number of beams remained. Results of optimization of beam weights and angles using these algorithms were compared using a standard cadre of abdominal cases. The solution space was defined as a set of 36 custom-shaped open and wedged-filtered fields at 10 deg. increments with a target constant target volume margin of 1.2 cm. For each case a clinically-accepted cost function, minimum tumor dose was maximized subject to a set of normal tissue binary dose-volume constraints. For this study, the optimized plan was restricted to four (4) fields suitable for delivery with conventional therapy equipment. Results: The table gives the mean value of the minimum target dose obtained for each algorithm averaged over 5 different runs and the comparable manual treatment

  9. Treatment planning optimisation in proton therapy

    Science.gov (United States)

    McGowan, S E; Burnet, N G; Lomax, A J

    2013-01-01

    ABSTRACT. The goal of radiotherapy is to achieve uniform target coverage while sparing normal tissue. In proton therapy, the same sources of geometric uncertainty are present as in conventional radiotherapy. However, an important and fundamental difference in proton therapy is that protons have a finite range, highly dependent on the electron density of the material they are traversing, resulting in a steep dose gradient at the distal edge of the Bragg peak. Therefore, an accurate knowledge of the sources and magnitudes of the uncertainties affecting the proton range is essential for producing plans which are robust to these uncertainties. This review describes the current knowledge of the geometric uncertainties and discusses their impact on proton dose plans. The need for patient-specific validation is essential and in cases of complex intensity-modulated proton therapy plans the use of a planning target volume (PTV) may fail to ensure coverage of the target. In cases where a PTV cannot be used, other methods of quantifying plan quality have been investigated. A promising option is to incorporate uncertainties directly into the optimisation algorithm. A further development is the inclusion of robustness into a multicriteria optimisation framework, allowing a multi-objective Pareto optimisation function to balance robustness and conformity. The question remains as to whether adaptive therapy can become an integral part of a proton therapy, to allow re-optimisation during the course of a patient's treatment. The challenge of ensuring that plans are robust to range uncertainties in proton therapy remains, although these methods can provide practical solutions. PMID:23255545

  10. Clinical treatment planning for subjects undergoing boron neutron capture therapy at Harvard-MIT

    International Nuclear Information System (INIS)

    Zamenhof, R.G.; Palmer, M.R.; Buse, P.M.

    2001-01-01

    Treatment planning is a crucial component of the Harvard-MIT boron neutron capture therapy (BNCT) clinical trials. Treatment planning can be divided into five stages: (1) pre-planning, based on CT and MRI scans obtained when the subject arrives at the hospital and on assumed boron-10 distribution parameters; (2) subject set-up, or simulation, in the MITR-II medical therapy room to determine the boundary conditions for possible set-up configurations; (3) re-planning, following the subject simulation; (4) final localization of the subject in the medical therapy room for BNCT; and (5) final post facto recalculation of the doses delivered based on firm knowledge of the blood boron-10 concentration profiles and the neutron flux histories from precise online monitoring. The computer-assisted treatment planning is done using a specially written BNCT treatment planning code called MacNCTPLAN. The code uses the Los Alamos National Laboratory's Monte Carlo n-particle radiation transport code MCNPv.4b as the dose calculation engine and advanced anatomical model simulation based on an automatic evaluation of CT scan data. Results are displayed as isodose contours and dose-volume histograms, the latter correlated precisely with corresponding anatomical CT or MRI image planes. Examples of typical treatment planning scenarios will be presented. (author)

  11. Ferromagnetism in diluted magnetic semiconductors: A comparision between AB INITIO mean-field, RPA, and Monte Carlo treatments

    Czech Academy of Sciences Publication Activity Database

    Bouzerar, G.; Kudrnovský, Josef; Bergqist, L.; Bruno, P.

    2003-01-01

    Roč. 68, č. 8 (2003), s. 081203-1 - 081203-4 ISSN 0163-1829 R&D Projects: GA AV ČR IAA1010203 Grant - others:RTN(XX) HPRN-CT-2000-00143 Institutional research plan: CEZ:AV0Z1010914 Keywords : Curie temperature * diluted magnetic semiconductors * mean-field * RPA * Monte-Carlo Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.962, year: 2003

  12. Strategic planning of treatment for hyperthyroid disease

    International Nuclear Information System (INIS)

    Hoeffer, R.

    1994-01-01

    Strategic planning of treatment of hyperthyroid disease must correspond to the pathophysiological mechanism of elevation of thyroid hormone serum concentration, i.e. excess stimulation, autonomous thyroid function, destruction induced hyperthyoroxinemia. In cases of excess stimulation one should go to extremes to save the essentially 'normal' thyroid gland and life-long antithyroid drug treatment confronts with total ablation of the thyroid gland in non remitting disease. Size and quantity of regions of autonomously functioning follicles/cells will be the determinant of therapeutic strategy in cases of autonomous thyroid function. Selective surgery confronts with radioiodine treatment aiming at 'restitutio ad integrum'. In destruction induced hyperthyroxinemia antiintlammatory and symptomatic measures may help to bridge the time to the return of normal hormone concentrations. Based on these considerations a detailed therapeutic strategy for hyperthyroid disease can be designed. (author)

  13. A feasibility study to calculate unshielded fetal doses to pregnant patients in 6-MV photon treatments using Monte Carlo methods and anatomically realistic phantoms

    International Nuclear Information System (INIS)

    Bednarz, Bryan; Xu, X. George

    2008-01-01

    A Monte Carlo-based procedure to assess fetal doses from 6-MV external photon beam radiation treatments has been developed to improve upon existing techniques that are based on AAPM Task Group Report 36 published in 1995 [M. Stovall et al., Med. Phys. 22, 63-82 (1995)]. Anatomically realistic models of the pregnant patient representing 3-, 6-, and 9-month gestational stages were implemented into the MCNPX code together with a detailed accelerator model that is capable of simulating scattered and leakage radiation from the accelerator head. Absorbed doses to the fetus were calculated for six different treatment plans for sites above the fetus and one treatment plan for fibrosarcoma in the knee. For treatment plans above the fetus, the fetal doses tended to increase with increasing stage of gestation. This was due to the decrease in distance between the fetal body and field edge with increasing stage of gestation. For the treatment field below the fetus, the absorbed doses tended to decrease with increasing gestational stage of the pregnant patient, due to the increasing size of the fetus and relative constant distance between the field edge and fetal body for each stage. The absorbed doses to the fetus for all treatment plans ranged from a maximum of 30.9 cGy to the 9-month fetus to 1.53 cGy to the 3-month fetus. The study demonstrates the feasibility to accurately determine the absorbed organ doses in the mother and fetus as part of the treatment planning and eventually in risk management

  14. 3-D CT for cardiovascular treatment planning

    International Nuclear Information System (INIS)

    Wildermuth, S.; Leschka, S.; Duru, F.; Alkadhi, H.

    2005-01-01

    The recently developed 64-slice CT scanner together with the use of 2-D and 3-D reconstructions can aid the cardiovascular surgeon and interventional radiologist in visualizing exact geometric relationships to plan and execute complex procedures via minimally invasive or standard approaches.Cardiac 64-slice CT considerably benefits from the high temporal and spatial resolution allowing the reliable depiction of small coronary segments. Similarly, abdominal vascular 64-slice CT became possible within short examination times and allowing an optimal arterial contrast bolus exploitation. We demonstrate four representative cardiac and abdominal examples using the new 64-slice CT technology which reveal the impact of the new scanner generation for cardiovascular treatment planning. (orig.)

  15. Intracavitary radiation treatment planning and dose evaluation

    International Nuclear Information System (INIS)

    Anderson, L.L.; Masterson, M.E.; Nori, D.

    1987-01-01

    Intracavitary radiation therapy with encapsulated radionuclide sources has generally involved, since the advent of afterloading techniques, inserting the sources in tubing previously positioned within a body cavity near the region to be treated. Because of the constraints on source locations relative to the target region, the functions of treatment planning and dose evaluation, usually clearly separable in interstitial brachytherapy, tend to merge in intracavitary therapy. Dose evaluation is typically performed for multiple source-strength configurations in the process of planning and thus may be regarded as complete when a particular configuration has been selected. The input data for each dose evaluation, of course, must include reliable dose distribution information for the source-applicator combinations used. Ultimately, the goal is to discover the source-strength configuration that results in the closest possible approach to the dose distribution desired

  16. Effect of gold nanoparticles on radiation doses in tumor treatment: a Monte Carlo study.

    Science.gov (United States)

    Al-Musywel, H A; Laref, A

    2017-12-01

    Radiotherapy is an extensively used treatment for most tumor types. However, ionizing radiation does not discriminate between cancerous and normal cells surrounding the tumor, which can be considered as a dose-limiting factor. This can lead to the reduction of the effectiveness of tumor cell eradication with this treatment. A potential solution to this problem is loading the tumor with high-Z materials prior to radiotherapy as this can induce higher toxicity in tumor cells compared to normal ones. New advances in nanotechnology have introduced the promising use of heavy metal nanoparticles to enhance tumor treatment. The primary studies showed that gold nanoparticles (GNPs) have unique characteristics as biocompatible radiosensitizers for tumor cells. This study aimed to quantify the dose enhancement effect and its radial dose distribution by Monte Carlo simulations utilizing the EGSnrc code for the water-gold phantom loaded with seven different concentrations of Au: 0, 7, 18, 30, 50, 75, and 100 mg-Au/g-water. The phantom was irradiated with two different radionuclide sources, Ir-192 and Cs-137, which are commonly used in brachytherapy, for all concentrations. The results exhibited that gold nanoparticle-aided radiotherapy (GNRT) increases the efficacy of radiotherapy with low-energy photon sources accompanied with high Au concentration loads of up to 30 mg-Au/g-water. Our finding conducts also to the detection of dose enhancement effects in a short average range of 650 μm outside the region loaded with Au. This can indicate that the location determination is highly important in this treatment method.

  17. Specialized Monte Carlo codes versus general-purpose Monte Carlo codes

    International Nuclear Information System (INIS)

    Moskvin, Vadim; DesRosiers, Colleen; Papiez, Lech; Lu, Xiaoyi

    2002-01-01

    The possibilities of Monte Carlo modeling for dose calculations and optimization treatment are quite limited in radiation oncology applications. The main reason is that the Monte Carlo technique for dose calculations is time consuming while treatment planning may require hundreds of possible cases of dose simulations to be evaluated for dose optimization. The second reason is that general-purpose codes widely used in practice, require an experienced user to customize them for calculations. This paper discusses the concept of Monte Carlo code design that can avoid the main problems that are preventing wide spread use of this simulation technique in medical physics. (authors)

  18. A Monte Carlo Examination of an MTMM Model with Planned Incomplete Data Structures.

    Science.gov (United States)

    Bunting, Brendan P.; Adamson, Gary; Mulhall, Peter K.

    2002-01-01

    Studied planned incomplete data designs for the purpose of substantially reducing the amount of data required for multitrait-multimethod models. Simulations studied the effectiveness of Listwise Deletion, Pairwise Deletion, and the expectation maximization (EM) algorithm. Results indicate that EM is generally precise and efficient. (SLD)

  19. Treatment Plan Adherence for Your Child With JA

    Science.gov (United States)

    ... or her treatment plan with the best of intentions. Anxious for their child with juvenile arthritis to ... or her treatment plan with the best of intentions. Anxious for their child with juvenile arthritis to ...

  20. Science-based strategic planning for hazardous fuel treatment.

    Science.gov (United States)

    D.L. Peterson; M.C. Johnson

    2007-01-01

    A scientific foundation coupled with technical support is needed to develop long-term strategic plans for fuel and vegetation treatments on public lands. These plans are developed at several spatial scales and are typically a component of fire management plans and other types of resource management plans. Such plans need to be compatible with national, regional, and...

  1. Energy planning of a hospital using Mathematical Programming and Monte Carlo simulation for dealing with uncertainty in the economic parameters

    Energy Technology Data Exchange (ETDEWEB)

    Mavrotas, George; Florios, Kostas; Vlachou, Dimitra [Laboratory of Industrial and Energy Economics, School of Chemical Engineering, National Technical University of Athens, Zographou Campus, 15780 Athens (Greece)

    2010-04-15

    For more than 40 years, Mathematical Programming is the traditional tool for energy planning at the national or regional level aiming at cost minimization subject to specific technological, political and demand satisfaction constraints. The liberalization of the energy market along with the ongoing technical progress increased the level of competition and forced energy consumers, even at the unit level, to make their choices among a large number of alternative or complementary energy technologies, fuels and/or suppliers. In the present work we develop a modelling framework for energy planning in units of the tertiary sector giving special emphasis to model reduction and to the uncertainty of the economic parameters. In the given case study, the energy rehabilitation of a hospital in Athens is examined and the installation of a cogeneration, absorption and compression unit is examined for the supply of the electricity, heating and cooling load. The basic innovation of the given energy model lies in the uncertainty modelling through the combined use of Mathematical Programming (namely, Mixed Integer Linear Programming, MILP) and Monte Carlo simulation that permits the risk management for the most volatile parameters of the objective function such as the fuel costs and the interest rate. The results come in the form of probability distributions that provide fruitful information to the decision maker. The effect of model reduction through appropriate data compression of the load data is also addressed. (author)

  2. 49: 3-D treatment planning. 3

    International Nuclear Information System (INIS)

    Fraass, B.A.; McShan, D.L.; Weeks, K.J.

    1987-01-01

    For practical 3-D treatment planning, one of the most important perspectives to be used is the 'beam's-eye-view' (BEV), since it displays the relationship of the target volume with the proposed radiation beams. Several BEV features comprise the 3-D planning system U-MPlan, including BEV displays which include contour and shaded solid surfaces of defined anatomy, block entry using joystick and digitizer tablet, automatic block and multi-leaf collimator design, output of block coordinates to hard copy devices, direct output to a computer-controlled block and compensator cutter, use of video digitized radiographs as a backdrop for the BEV graphics, image analysis of digitized films, complete image correlation between BEV-type imaging and CT, MR, PET, etc., and a photon dose calculation algorithm which makes accurate and fast calculations in BEV planes and under blocks. The correlation and use of radiographs and other BEV-type images with CT-type information allows a new degree of precision to be incorporated into radiation therapy planning. 9 refs.; 3 figs

  3. Recovery post treatment: plans, barriers and motivators

    Directory of Open Access Journals (Sweden)

    Duffy Paul

    2013-01-01

    Full Text Available Abstract Background The increasing focus on achieving a sustained recovery from substance use brings with it a need to better understand the factors (recovery capital that contribute to recovery following treatment. This work examined the factors those in recovery perceive to be barriers to (lack of capital or facilitators of (presence of capital sustained recovery post treatment. Methods A purposive sample of 45 participants was recruited from 11 drug treatment services in northern England. Semi-structured qualitative interviews lasting between 30 and 90 minutes were conducted one to three months after participants completed treatment. Interviews examined key themes identified through previous literature but focused on allowing participants to explore their unique recovery journey. Interviews were transcribed and analysed thematically using a combination of deductive and inductive approaches. Results Participants generally reported high levels of confidence in maintaining their recovery with most planning to remain abstinent. There were indications of high levels of recovery capital. Aftercare engagement was high, often through self referral, with non substance use related activity felt to be particularly positive. Supported housing was critical and concerns were raised about the ability to afford to live independently with financial stability and welfare availability a key concern in general. Employment, often in the substance use treatment field, was a desire. However, it was a long term goal, with substantial risks associated with pursuing this too early. Positive social support was almost exclusively from within the recovery community although the re-building of relationships with family (children in particular was a key motivator post treatment. Conclusions Addressing internal factors and underlying issues i.e. ‘human capital’, provided confidence for continued recovery whilst motivators focused on external factors such as family and

  4. Constrained treatment planning using sequential beam selection

    International Nuclear Information System (INIS)

    Woudstra, E.; Storchi, P.R.M.

    2000-01-01

    In this paper an algorithm is described for automated treatment plan generation. The algorithm aims at delivery of the prescribed dose to the target volume without violation of constraints for target, organs at risk and the surrounding normal tissue. Pre-calculated dose distributions for all candidate orientations are used as input. Treatment beams are selected in a sequential way. A score function designed for beam selection is used for the simultaneous selection of beam orientations and weights. In order to determine the optimum choice for the orientation and the corresponding weight of each new beam, the score function is first redefined to account for the dose distribution of the previously selected beams. Addition of more beams to the plan is stopped when the target dose is reached or when no additional dose can be delivered without violating a constraint. In the latter case the score function is modified by importance factor changes to enforce better sparing of the organ with the limiting constraint and the algorithm is run again. (author)

  5. Novel tracer for radiation treatment planning

    International Nuclear Information System (INIS)

    Schwarzenboeck, S.; Krause, B.J.; Herrmann, K.; Gaertner, F.; Souvatzoglou, M.; Klaesner, B.

    2011-01-01

    PET and PET/CT with innovative tracers gain increasing importance in diagnosis and therapy management, and radiation treatment planning in radio-oncology besides the widely established FDG. The introduction of [ 18 F]Fluorothymidine ([ 18 F]FLT) as marker of proliferation, [ 18 F]Fluoromisonidazole ([ 18 F]FMISO) and [ 18 F]Fluoroazomycin-Arabinoside ([ 18 F]FAZA) as tracer of hypoxia, [ 18 F]Fluoroethyltyrosine ([ 18 F]FET) and [ 11 C]Methionine for brain tumour imaging, [ 68 Ga]DOTATOC for somatostatin receptor imaging, [ 18 F]FDOPA for dopamine synthesis and radioactively labeled choline derivatives for imaging phospholipid metabolism have opened novel approaches to tumour imaging. Some of these tracers have already been implemented into radio-oncology: Amino acid PET and PET/CT have the potential to optimise radiation treatment planning of brain tumours through accurate delineation of tumour tissue from normal tissue, necrosis and edema. Hypoxia represents a major therapeutic problem in radiation therapy. Hypoxia imaging is very attractive as it may allow to increase the dose in hypoxic tumours potentially allowing for a better tumour control. Advances in hybrid imaging, i.e. the introduction of MR/PET, may also have an impact in radio-oncology through synergies related to the combination of molecular signals of PET and a high soft tissue contrast of MRI as well as functional MRI capabilities. (orig.)

  6. Oral diagnosis and treatment planning: part 6. Preventive and treatment planning for periodontal disease.

    Science.gov (United States)

    Corbet, E; Smales, R

    2012-09-01

    A high level of sustained personal plaque control is fundamental for successful treatment outcomes in patients with active periodontal disease and, hence, oral hygiene instructions are the cornerstone of periodontal treatment planning. Other risk factors for periodontal disease also should be identified and modified where possible. Many restorative dental treatments in particular require the establishment of healthy periodontal tissues for their clinical success. Failure by patients to control dental plaque because of inappropriate designs and materials for restorations and prostheses will result in the long-term failure of the restorations and the loss of supporting tissues. Periodontal treatment planning considerations are also very relevant to endodontic, orthodontic and osseointegrated dental implant conditions and proposed therapies.

  7. SU-F-T-444: Quality Improvement Review of Radiation Therapy Treatment Planning in the Presence of Dental Implants

    International Nuclear Information System (INIS)

    Parenica, H; Ford, J; Mavroidis, P; Li, Y; Stathakis, S; Papanikolaou, N

    2016-01-01

    Purpose: To quantify and compare the effect of metallic dental implants (MDI) on dose distributions calculated using Collapsed Cone Convolution Superposition (CCCS) algorithm or a Monte Carlo algorithm (with and without correcting for the density of the MDI). Methods: Seven previously treated patients to the head and neck region were included in this study. The MDI and the streaking artifacts on the CT images were carefully contoured. For each patient a plan was optimized and calculated using the Pinnacle3 treatment planning system (TPS). For each patient two dose calculations were performed, a) with the densities of the MDI and CT artifacts overridden (12 g/cc and 1 g/cc respectively) and b) without density overrides. The plans were then exported to the Monaco TPS and recalculated using Monte Carlo dose calculation algorithm. The changes in dose to PTVs and surrounding Regions of Interest (ROIs) were examined between all plans. Results: The Monte Carlo dose calculation indicated that PTVs received 6% lower dose than the CCCS algorithm predicted. In some cases, the Monte Carlo algorithm indicated that surrounding ROIs received higher dose (up to a factor of 2). Conclusion: Not properly accounting for dental implants can impact both the high dose regions (PTV) and the low dose regions (OAR). This study implies that if MDI and the artifacts are not appropriately contoured and given the correct density, there is potential significant impact on PTV coverage and OAR maximum doses.

  8. SU-F-T-444: Quality Improvement Review of Radiation Therapy Treatment Planning in the Presence of Dental Implants

    Energy Technology Data Exchange (ETDEWEB)

    Parenica, H; Ford, J [Texas A& M University, College Station, TX (United States); Mavroidis, P [University of North Carolina, Chapel Hill, NC, (United States); Li, Y; Stathakis, S [Cancer Therapy and Research Center, San Antonio, TX (United States); Papanikolaou, N [University of Texas Health Science Center at San Antonio, San Antonio, TX (United States)

    2016-06-15

    Purpose: To quantify and compare the effect of metallic dental implants (MDI) on dose distributions calculated using Collapsed Cone Convolution Superposition (CCCS) algorithm or a Monte Carlo algorithm (with and without correcting for the density of the MDI). Methods: Seven previously treated patients to the head and neck region were included in this study. The MDI and the streaking artifacts on the CT images were carefully contoured. For each patient a plan was optimized and calculated using the Pinnacle3 treatment planning system (TPS). For each patient two dose calculations were performed, a) with the densities of the MDI and CT artifacts overridden (12 g/cc and 1 g/cc respectively) and b) without density overrides. The plans were then exported to the Monaco TPS and recalculated using Monte Carlo dose calculation algorithm. The changes in dose to PTVs and surrounding Regions of Interest (ROIs) were examined between all plans. Results: The Monte Carlo dose calculation indicated that PTVs received 6% lower dose than the CCCS algorithm predicted. In some cases, the Monte Carlo algorithm indicated that surrounding ROIs received higher dose (up to a factor of 2). Conclusion: Not properly accounting for dental implants can impact both the high dose regions (PTV) and the low dose regions (OAR). This study implies that if MDI and the artifacts are not appropriately contoured and given the correct density, there is potential significant impact on PTV coverage and OAR maximum doses.

  9. Hexone Storage and Treatment Facility closure plan

    International Nuclear Information System (INIS)

    1992-11-01

    The HSTF is a storage and treatment unit subject to the requirements for the storage and treatment of dangerous waste. Closure is being conducted under interim status and will be completed pursuant to the requirements of Washington State Department of Ecology (Ecology) Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-610 and WAC 173-303-640. Because dangerous waste does not include the source, special nuclear, and by-product material components of mixed waste, radionuclides are not within the scope of WAC 173-303 or of this closure plan. The information on radionuclides is provided only for general knowledge where appropriate. The known hazardous/dangerous waste remaining at the site before commencing other closure activities consists of the still vessels, a tarry sludge in the storage tanks, and residual contamination in equipment, piping, filters, etc. The treatment and removal of waste at the HSTF are closure activities as defined in the Resource Conservation and Recovery Act (RCRA) of 1976 and WAC 173-303

  10. Radiation treatment planning using a microcomputer

    International Nuclear Information System (INIS)

    Lunsqui, A.R.; Calil, S.J.; Rocha, J.R.O.; Alexandre, A.C.

    1990-01-01

    The radiation treatment planning requires a lenght manipulation of data from isodose charts to obtain the best irradiation technique. Over the past 25 years this tedious operation has been replaced by computerized methods. These can reduce the working time by at least 20 times. It is being developed at the Biomedical Engineering Center a software to generate a polychromatic image of dose distribution. By means of a digitizing board, the patient contour and the beam data are transfered to the computer and stored as polinomial and Fourier series respectively. To calculate the dose distribution, the irradiated region is represented by a variable size bidimensional dot matrix. The dose at each point is calculated by correcting and adding the stored data for each beam. An algorithm for color definition according to the dose intensity was developed to display on a computer monitor the resultant matrix. A hard copy can be obtained be means of a six color plotter. (author)

  11. MO-B-BRB-00: Optimizing the Treatment Planning Process

    International Nuclear Information System (INIS)

    2015-01-01

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  12. MO-B-BRB-00: Optimizing the Treatment Planning Process

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  13. 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

  14. Development of reference problems for neutron capture therapy treatment planning systems

    International Nuclear Information System (INIS)

    Albritton, J.R.; Kiger, W.S. III

    2006-01-01

    Currently, 5 different treatment planning systems (TPSs) are or have been used in clinical trials of Neutron Capture Therapy (NCT): MacNCTPlan, NCTPlan, BNCT Rtpe, SERA, and JCDS. This paper describes work performed to comprehensively test and compare 4 of these NCT treatment planning systems in order to facilitate the pooling of patient data from the different clinical sites for analysis of the clinical results as well as to provide an important quality assurance tool for existing and future TPSs. Two different phantoms were used to evaluate the planning systems: the modified Snyder head phantom and a large water-filled box, similar to that used in the International Dosimetry Exchange for NCT. The comparison of the resulting dose profile, isodose contours, and dose volume histograms to reference calculations performed with the Monte Carlo radiation transport code MCNP5 yielded many interesting differences. Each of the planning systems deviated from the reference calculations, with the newer systems (i.e., SERA and NCTPlan) most often yielding better agreement than their predecessors (i.e., BNCT Rtpe and MacNCTPlan). The combination of simple phantoms and sources with more complicated and realistic planning conditions has produced a well-rounded and useful suite of test problems for NCT treatment planning system analysis. (author)

  15. Accuracy requirements in radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Buzdar, S. A.; Afzal, M.; Nazir, A.; Gadhi, M. A.

    2013-01-01

    Radiation therapy attempts to deliver ionizing radiation to the tumour and can improve the survival chances and/or quality of life of patients. There are chances of errors and uncertainties in the entire process of radiotherapy that may affect the accuracy and precision of treatment management and decrease degree of conformation. All expected inaccuracies, like radiation dose determination, volume calculation, complete evaluation of the full extent of the tumour, biological behaviour of specific tumour types, organ motion during radiotherapy, imaging, biological/molecular uncertainties, sub-clinical diseases, microscopic spread of the disease, uncertainty in normal tissue responses and radiation morbidity need sound appreciation. Conformity can be increased by reduction of such inaccuracies. With the yearly increase in computing speed and advancement in other technologies the future will provide the opportunity to optimize a greater number of variables and reduce the errors in the treatment planning process. In multi-disciplined task of radiotherapy, efforts are needed to overcome the errors and uncertainty, not only by the physicists but also by radiologists, pathologists and oncologists to reduce molecular and biological uncertainties. The radiation therapy physics is advancing towards an optimal goal that is definitely to improve accuracy where necessary and to reduce uncertainty where possible. (author)

  16. A treatment planning classification for oligodontia.

    Science.gov (United States)

    Singer, Steven L; Henry, Patrick J; Lander, Ian D

    2010-01-01

    The aim of this research was to provide a classification for patients with oligodontia that could act as an aid in treatment planning. Panoramic radiograph records of 70 patients with oligodontia were used to categorize the extent of the disability and treatment modality. Patients were classified into types 1 through 3 depending on the number of missing primary and permanent teeth, as well as in relation to their prosthodontic requirements. The radiographs were then assessed independently on two separate occasions by three experienced clinicians to validate the classification. There was a high level of intrarater consistency in allocating patients into the three different types with a Kappa (k) score of 0.77 for clinician 1, 0.87 for clinician 2, and 0.94 for clinician 3. There was also a strong interrater agreement (overall k score: 0.88). A k score greater then 0.6 is regarded as being good and greater than 0.8 as being very good. Oligodontia is a heterogeneous condition. Patients with oligodontia can be classified as having three different types according to the extent of their disability and the complexity of their prosthodontic requirements. This classification is a reliable diagnostic tool based on the positive outcome of the inter- and intrarater consistency.

  17. Volume visualization in radiation treatment planning.

    Science.gov (United States)

    Pelizzari, C A; Chen, G T

    2000-12-01

    Radiation treatment planning (RTP), historically an image-intensive discipline and one of the first areas in which 3D information from imaging was clinically applied, has become even more critically dependent on accurate 3D definition of target and non-target structures in recent years with the advent of conformal radiation therapy. In addition to the interactive display of wireframe or shaded surface models of anatomic objects, proposed radiation beams, beam modifying devices, and calculated dose distributions, recently significant use has been made of direct visualization of relevant anatomy from image data. Dedicated systems are commercially available for the purpose of geometrically optimizing beam placement, implementing in virtual reality the functionality of standard radiation therapy simulators. Such "CT simulation" systems rely heavily on 3D visualization and on reprojection of image data to produce simulated radiographs for comparison with either diagnostic-quality radiographs made on a simulator or megavoltage images made using the therapeutic beams themselves. Although calculation and analysis of dose distributions is an important component of radiation treatment design, geometric targeting with optimization based on 3D anatomic information is frequently performed as a separate step independent of dose calculations.

  18. Monte Carlo dose distributions for radiosurgery

    International Nuclear Information System (INIS)

    Perucha, M.; Leal, A.; Rincon, M.; Carrasco, E.

    2001-01-01

    The precision of Radiosurgery Treatment planning systems is limited by the approximations of their algorithms and by their dosimetrical input data. This fact is especially important in small fields. However, the Monte Carlo methods is an accurate alternative as it considers every aspect of particle transport. In this work an acoustic neurinoma is studied by comparing the dose distribution of both a planning system and Monte Carlo. Relative shifts have been measured and furthermore, Dose-Volume Histograms have been calculated for target and adjacent organs at risk. (orig.)

  19. Radiotherapy Treatment Planning for Testicular Seminoma

    International Nuclear Information System (INIS)

    Wilder, Richard B.; Buyyounouski, Mark K.; Efstathiou, Jason A.; Beard, Clair J.

    2012-01-01

    Virtually all patients with Stage I testicular seminoma are cured regardless of postorchiectomy management. For patients treated with adjuvant radiotherapy, late toxicity is a major concern. However, toxicity may be limited by radiotherapy techniques that minimize radiation exposure of healthy normal tissues. This article is an evidence-based review that provides radiotherapy treatment planning recommendations for testicular seminoma. The minority of Stage I patients who choose adjuvant treatment over surveillance may be considered for (1) para-aortic irradiation to 20 Gy in 10 fractions, or (2) carboplatin chemotherapy consisting of area under the curve, AUC = 7 × 1−2 cycles. Two-dimensional radiotherapy based on bony anatomy is a simple and effective treatment for Stage IIA or IIB testicular seminoma. Centers with expertise in vascular and nodal anatomy may consider use of anteroposterior–posteroanterior fields based on three-dimensional conformal radiotherapy instead. For modified dog-leg fields delivering 20 Gy in 10 fractions, clinical studies support placement of the inferior border at the top of the acetabulum. Clinical and nodal mapping studies support placement of the superior border of all radiotherapy fields at the top of the T12 vertebral body. For Stage IIA and IIB patients, an anteroposterior–posteroanterior boost is then delivered to the adenopathy with a 2-cm margin to the block edge. The boost dose consists of 10 Gy in 5 fractions for Stage IIA and 16 Gy in 8 fractions for Stage IIB. Alternatively, bleomycin, etoposide, and cisplatin chemotherapy for 3 cycles or etoposide and cisplatin chemotherapy for 4 cycles may be delivered to Stage IIA or IIB patients (e.g., if they have a horseshoe kidney, inflammatory bowel disease, or a history of radiotherapy).

  20. Implementation and verification of nuclear interactions in a Monte-Carlo code for the Procom-ProGam proton therapy planning system

    International Nuclear Information System (INIS)

    Kostyuchenko, V.I.; Makarova, A.S.; Ryazantsev, O.B.; Samarin, S.I.; Uglov, A.S.

    2013-01-01

    Proton interaction with an exposed object material needs to be modeled with account for three basic processes: electromagnetic stopping of protons in matter, multiple coulomb scattering and nuclear interactions. Just the last type of processes is the topic of this paper. Monte Carlo codes are often used to simulate high-energy particle interaction with matter. However, nuclear interaction models implemented in these codes are rather extensive and their use in treatment planning systems requires huge computational resources. We have selected the IThMC code for its ability to reproduce experiments which measure the distribution of the projected ranges of nuclear secondary particles generated by proton beams in a multi-layer Faraday cup. The multi-layer Faraday cup detectors measure charge rather than dose and allow distinguishing between electromagnetic and nuclear interactions. The event generator used in the IThMC code is faster, but less accurate than any other used in testing. Our model of nuclear reactions demonstrates quite good agreement with experiment in the context of their effect on the Bragg peak in therapeutic applications

  1. Head-and-neck IMRT treatments assessed with a Monte Carlo dose calculation engine

    International Nuclear Information System (INIS)

    Seco, J; Adams, E; Bidmead, M; Partridge, M; Verhaegen, F

    2005-01-01

    IMRT is frequently used in the head-and-neck region, which contains materials of widely differing densities (soft tissue, bone, air-cavities). Conventional methods of dose computation for these complex, inhomogeneous IMRT cases involve significant approximations. In the present work, a methodology for the development, commissioning and implementation of a Monte Carlo (MC) dose calculation engine for intensity modulated radiotherapy (MC-IMRT) is proposed which can be used by radiotherapy centres interested in developing MC-IMRT capabilities for research or clinical evaluations. The method proposes three levels for developing, commissioning and maintaining a MC-IMRT dose calculation engine: (a) development of a MC model of the linear accelerator, (b) validation of MC model for IMRT and (c) periodic quality assurance (QA) of the MC-IMRT system. The first step, level (a), in developing an MC-IMRT system is to build a model of the linac that correctly predicts standard open field measurements for percentage depth-dose and off-axis ratios. Validation of MC-IMRT, level (b), can be performed in a rando phantom and in a homogeneous water equivalent phantom. Ultimately, periodic quality assurance of the MC-IMRT system is needed to verify the MC-IMRT dose calculation system, level (c). Once the MC-IMRT dose calculation system is commissioned it can be applied to more complex clinical IMRT treatments. The MC-IMRT system implemented at the Royal Marsden Hospital was used for IMRT calculations for a patient undergoing treatment for primary disease with nodal involvement in the head-and-neck region (primary treated to 65 Gy and nodes to 54 Gy), while sparing the spinal cord, brain stem and parotid glands. Preliminary MC results predict a decrease of approximately 1-2 Gy in the median dose of both the primary tumour and nodal volumes (compared with both pencil beam and collapsed cone). This is possibly due to the large air-cavity (the larynx of the patient) situated in the centre

  2. SU-F-T-364: Monte Carlo-Dose Verification of Volumetric Modulated Arc Therapy Plans Using AAPM TG-119 Test Patterns

    International Nuclear Information System (INIS)

    Onizuka, R; Araki, F; Ohno, T; Nakaguchi, Y

    2016-01-01

    Purpose: To investigate the Monte Carlo (MC)-based dose verification for VMAT plans by a treatment planning system (TPS). Methods: The AAPM TG-119 test structure set was used for VMAT plans by the Pinnacle3 (convolution/superposition), using a Synergy radiation head of a 6 MV beam with the Agility MLC. The Synergy was simulated with the EGSnrc/BEAMnrc code, and VMAT dose distributions were calculated with the EGSnrc/DOSXYZnrc code by the same irradiation conditions as TPS. VMAT dose distributions of TPS and MC were compared with those of EBT3 film, by 2-D gamma analysis of ±3%/3 mm criteria with a threshold of 30% of prescribed doses. VMAT dose distributions between TPS and MC were also compared by DVHs and 3-D gamma analysis of ±3%/3 mm criteria with a threshold of 10%, and 3-D passing rates for PTVs and OARs were analyzed. Results: TPS dose distributions differed from those of film, especially for Head & neck. The dose difference between TPS and film results from calculation accuracy for complex motion of MLCs like tongue and groove effect. In contrast, MC dose distributions were in good agreement with those of film. This is because MC can model fully the MLC configuration and accurately reproduce the MLC motion between control points in VMAT plans. D95 of PTV for Prostate, Head & neck, C-shaped, and Multi Target was 97.2%, 98.1%, 101.6%, and 99.7% for TPS and 95.7%, 96.0%, 100.6%, and 99.1% for MC, respectively. Similarly, 3-D gamma passing rates of each PTV for TPS vs. MC were 100%, 89.5%, 99.7%, and 100%, respectively. 3-D passing rates of TPS reduced for complex VMAT fields like Head & neck because MLCs are not modeled completely for TPS. Conclusion: MC-calculated VMAT dose distributions is useful for the 3-D dose verification of VMAT plans by TPS.

  3. SU-F-T-364: Monte Carlo-Dose Verification of Volumetric Modulated Arc Therapy Plans Using AAPM TG-119 Test Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Onizuka, R [Graduate School of Health Sciences, Kumamoto University (Japan); Araki, F; Ohno, T [Faculty of Life Sciences, Kumamoto University (Japan); Nakaguchi, Y [Kumamoto University Hospital (Japan)

    2016-06-15

    Purpose: To investigate the Monte Carlo (MC)-based dose verification for VMAT plans by a treatment planning system (TPS). Methods: The AAPM TG-119 test structure set was used for VMAT plans by the Pinnacle3 (convolution/superposition), using a Synergy radiation head of a 6 MV beam with the Agility MLC. The Synergy was simulated with the EGSnrc/BEAMnrc code, and VMAT dose distributions were calculated with the EGSnrc/DOSXYZnrc code by the same irradiation conditions as TPS. VMAT dose distributions of TPS and MC were compared with those of EBT3 film, by 2-D gamma analysis of ±3%/3 mm criteria with a threshold of 30% of prescribed doses. VMAT dose distributions between TPS and MC were also compared by DVHs and 3-D gamma analysis of ±3%/3 mm criteria with a threshold of 10%, and 3-D passing rates for PTVs and OARs were analyzed. Results: TPS dose distributions differed from those of film, especially for Head & neck. The dose difference between TPS and film results from calculation accuracy for complex motion of MLCs like tongue and groove effect. In contrast, MC dose distributions were in good agreement with those of film. This is because MC can model fully the MLC configuration and accurately reproduce the MLC motion between control points in VMAT plans. D95 of PTV for Prostate, Head & neck, C-shaped, and Multi Target was 97.2%, 98.1%, 101.6%, and 99.7% for TPS and 95.7%, 96.0%, 100.6%, and 99.1% for MC, respectively. Similarly, 3-D gamma passing rates of each PTV for TPS vs. MC were 100%, 89.5%, 99.7%, and 100%, respectively. 3-D passing rates of TPS reduced for complex VMAT fields like Head & neck because MLCs are not modeled completely for TPS. Conclusion: MC-calculated VMAT dose distributions is useful for the 3-D dose verification of VMAT plans by TPS.

  4. Developing a treatment planning process and software for improved translation of photodynamic therapy

    Science.gov (United States)

    Cassidy, J.; Zheng, Z.; Xu, Y.; Betz, V.; Lilge, L.

    2017-04-01

    Background: The majority of de novo cancers are diagnosed in low and middle-income countries, which often lack the resources to provide adequate therapeutic options. None or minimally invasive therapies such as Photodynamic Therapy (PDT) or photothermal therapies could become part of the overall treatment options in these countries. However, widespread acceptance is hindered by the current empirical training of surgeons in these optical techniques and a lack of easily usable treatment optimizing tools. Methods: Based on image processing programs, ITK-SNAP, and the publicly available FullMonte light propagation software, a work plan is proposed that allows for personalized PDT treatment planning. Starting with, contoured clinical CT or MRI images, the generation of 3D tetrahedral models in silico, execution of the Monte Carlo simulation and presentation of the 3D fluence rate, Φ, [mWcm-2] distribution a treatment plan optimizing photon source placement is developed. Results: Permitting 1-2 days for the installation of the required programs, novices can generate their first fluence, H [Jcm-2] or Φ distribution in a matter of hours. This is reduced to 10th of minutes with some training. Executing the photon simulation calculations is rapid and not the performance limiting process. Largest sources of errors are uncertainties in the contouring and unknown tissue optical properties. Conclusions: The presented FullMonte simulation is the fastest tetrahedral based photon propagation program and provides the basis for PDT treatment planning processes, enabling a faster proliferation of low cost, minimal invasive personalized cancer therapies.

  5. Treatment of input uncertainty in hydrologic modeling: Doing hydrology backward with Markov chain Monte Carlo simulation

    NARCIS (Netherlands)

    Vrugt, J.A.; Braak, ter C.J.F.; Clark, M.P.; Hyman, J.M.; Robinson, B.A.

    2008-01-01

    There is increasing consensus in the hydrologic literature that an appropriate framework for streamflow forecasting and simulation should include explicit recognition of forcing and parameter and model structural error. This paper presents a novel Markov chain Monte Carlo (MCMC) sampler, entitled

  6. Optimization of rotational radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Tulovsky, Vladimir; Ringor, Michael; Papiez, Lech

    1995-01-01

    Purpose: Rotational therapy treatment planning for rotationally symmetric geometry of tumor and healthy tissue provides an important example of testing various approaches to optimizing dose distributions for therapeutic x-ray irradiations. In this article, dose distribution optimization is formulated as a variational problem. This problem is solved analytically and numerically. Methods and Materials: The classical Lagrange method is used to derive equations and inequalities that give necessary conditions for minimizing the mean-square deviation between the ideal dose distribution and the achievable dose distribution. The solution of the resulting integral equation with Cauchy kernel is used to derive analytical formulas for the minimizing irradiation intensity function. Results: The solutions are evaluated numerically and the graphs of the minimizing intensity functions and the corresponding dose distributions are presented. Conclusions: The optimal solutions obtained using the mean-square criterion lead to significant underdosage in some areas of the tumor volume. Possible solutions to this shortcoming are investigated and medically more appropriate criteria for optimization are proposed for future investigations

  7. Federal Facilities Compliance Act, Conceptual Site Treatment Plan. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-10-29

    This Conceptual Site Treatment Plan was prepared by Ames Laboratory to meet the requirements of the Federal Facilities Compliance Act. Topics discussed in this document include: general discussion of the plan, including the purpose and scope; technical aspects of preparing plans, including the rationale behind the treatability groupings and a discussion of characterization issues; treatment technology needs and treatment options for specific waste streams; low-level mixed waste options; TRU waste options; and future waste generation from restoration activities.

  8. Federal Facilities Compliance Act, Conceptual Site Treatment Plan. Part 1

    International Nuclear Information System (INIS)

    1993-01-01

    This Conceptual Site Treatment Plan was prepared by Ames Laboratory to meet the requirements of the Federal Facilities Compliance Act. Topics discussed in this document include: general discussion of the plan, including the purpose and scope; technical aspects of preparing plans, including the rationale behind the treatability groupings and a discussion of characterization issues; treatment technology needs and treatment options for specific waste streams; low-level mixed waste options; TRU waste options; and future waste generation from restoration activities

  9. 3-D conformal radiation therapy - Part I: Treatment planning

    International Nuclear Information System (INIS)

    Mageras, Gikas S.

    1996-01-01

    Conformal radiation therapy shapes the high-dose volume so as to conform to the target volume while minamizing the dose to surrounding normal tissues. The advances that have been achieved in conformal therapy are in part due to the development of 3-dimensional 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. The objective of this course is to 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 future trends in 3D treatment planning, such as 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 the treatment planning process

  10. Accounting for the fringe magnetic field from the bending magnet in a Monte Carlo accelerator treatment head simulation.

    Science.gov (United States)

    O'Shea, Tuathan P; Foley, Mark J; Faddegon, Bruce A

    2011-06-01

    Monte Carlo (MC) simulation can be used for accurate electron beam treatment planning and modeling. Measurement of large electron fields, with the applicator removed and secondary collimator wide open, has been shown to provide accurate simulation parameters, including asymmetry in the measured dose, for the full range of clinical field sizes and patient positions. Recently, disassembly of the treatment head of a linear accelerator has been used to refine the simulation of the electron beam, setting tightly measured constraints on source and geometry parameters used in simulation. The simulation did not explicitly include the known deflection of the electron beam by a fringe magnetic field from the bending magnet, which extended into the treatment head. Instead, the secondary scattering foil and monitor chamber were unrealistically laterally offset to account for the beam deflection. This work is focused on accounting for this fringe magnetic field in treatment head simulation. The magnetic field below the exit window of a Siemens Oncor linear accelerator was measured with a Tesla-meter from 0 to 12 cm from the exit window and 1-3 cm off-axis. Treatment head simulation was performed with the EGSnrc/BEAMnrc code, modified to incorporate the effect of the magnetic field on charged particle transport. Simulations were used to analyze the sensitivity of dose profiles to various sources of asymmetry in the treatment head. This included the lateral spot offset and beam angle at the exit window, the fringe magnetic field and independent lateral offsets of the secondary scattering foil and electron monitor chamber. Simulation parameters were selected within the limits imposed by measurement uncertainties. Calculated dose distributions were then compared with those measured in water. The magnetic field was a maximum at the exit window, increasing from 0.006 T at 6 MeV to 0.020 T at 21 MeV and dropping to approximately 5% of the maximum at the secondary scattering foil. It

  11. Photodynamic therapy in neurosurgery: a proof of concept of treatment planning system

    Science.gov (United States)

    Dupont, C.; Reyns, N.; Mordon, S.; Vermandel, M.

    2017-02-01

    Glioblastoma (GBM) is the most common primary brain tumor. PhotoDynamic Therapy (PDT) appears as an interesting research field to improve GBM treatment. Nevertheless, PDT cannot fit into the current therapeutic modalities according to several reasons: the lack of reliable and reproducible therapy schemes (devices, light delivery system), the lack of consensus on a photosensitizer and the absence of randomized and controlled multicenter clinical trial. The main objective of this study is to bring a common support for PDT planning. Here, we describe a proof of concept of Treatment Planning System (TPS) dedicated to interstitial PDT for GBM treatment. The TPS was developed with the integrated development environment C++ Builder XE8 and the environment ArtiMED, developed in our laboratory. This software enables stereotactic registration of DICOM images, light sources insertion and an accelerated CUDA GPU dosimetry modeling. Although, Monte-Carlo is more robust to describe light diffusion in biological tissue, analytical model accelerated by GPU remains relevant for dose preview or fast reverse planning processes. Finally, this preliminary work proposes a new tool to plan interstitial or intraoperative PDT treatment and might be included in the design of future clinical trials in order to deliver PDT straightforwardly and homogenously in investigator centers.

  12. 105: BIODOC - a combined biological treatment planning and treatment organization system

    International Nuclear Information System (INIS)

    Baier, K.

    1987-01-01

    With biological planning in radiotherapy not only planning with regard to the total dose but also the complete consideration of dose-time relationships is understood. A combined biological planning and treatment system based on a DEC PDP 11/23 minicomputer is reported. The main functions are: biological treatment planning, organization of general activities, documentation, archiving and research

  13. Feature-based plan adaptation for fast treatment planning in scanned ion beam therapy

    International Nuclear Information System (INIS)

    Chen Wenjing; Gemmel, Alexander; Rietzel, Eike

    2013-01-01

    We propose a plan adaptation method for fast treatment plan generation in scanned ion beam therapy. Analysis of optimized treatment plans with carbon ions indicates that the particle number modulation of consecutive rasterspots in depth shows little variation throughout target volumes with convex shape. Thus, we extract a depth-modulation curve (DMC) from existing reference plans and adapt it for creation of new plans in similar treatment situations. The proposed method is tested with seven CT serials of prostate patients and three digital phantom datasets generated with the MATLAB code. Plans are generated with a treatment planning software developed by GSI using single-field uniform dose optimization for all the CT datasets to serve as reference plans and ‘gold standard’. The adapted plans are generated based on the DMC derived from the reference plans of the same patient (intra-patient), different patient (inter-patient) and phantoms (phantom-patient). They are compared with the reference plans and a re-positioning strategy. Generally, in 1 min on a standard PC, either a physical plan or a biological plan can be generated with the adaptive method provided that the new target contour is available. In all the cases, the V95 values of the adapted plans can achieve 97% for either physical or biological plans. V107 is always 0 indicating no overdosage, and target dose homogeneity is above 0.98 in all cases. The dose received by the organs at risk is comparable to the optimized plans. The plan adaptation method has the potential for on-line adaptation to deal with inter-fractional motion, as well as fast off-line treatment planning, with either the prescribed physical dose or the RBE-weighted dose. (paper)

  14. A dose homogeneity and conformity evaluation between ViewRay and pinnacle-based linear accelerator IMRT treatment plans

    Directory of Open Access Journals (Sweden)

    Daniel L Saenz

    2014-01-01

    Full Text Available ViewRay, a novel technology providing soft-tissue imaging during radiotherapy is investigated for treatment planning capabilities assessing treatment plan dose homogeneity and conformity compared with linear accelerator plans. ViewRay offers both adaptive radiotherapy and image guidance. The combination of cobalt-60 (Co-60 with 0.35 Tesla magnetic resonance imaging (MRI allows for magnetic resonance (MR-guided intensity-modulated radiation therapy (IMRT delivery with multiple beams. This study investigated head and neck, lung, and prostate treatment plans to understand what is possible on ViewRay to narrow focus toward sites with optimal dosimetry. The goal is not to provide a rigorous assessment of planning capabilities, but rather a first order demonstration of ViewRay planning abilities. Images, structure sets, points, and dose from treatment plans created in Pinnacle for patients in our clinic were imported into ViewRay. The same objectives were used to assess plan quality and all critical structures were treated as similarly as possible. Homogeneity index (HI, conformity index (CI, and volume receiving <20% of prescription dose (DRx were calculated to assess the plans. The 95% confidence intervals were recorded for all measurements and presented with the associated bars in graphs. The homogeneity index (D5/D95 had a 1-5% inhomogeneity increase for head and neck, 3-8% for lung, and 4-16% for prostate. CI revealed a modest conformity increase for lung. The volume receiving 20% of the prescription dose increased 2-8% for head and neck and up to 4% for lung and prostate. Overall, for head and neck Co-60 ViewRay treatments planned with its Monte Carlo treatment planning software were comparable with 6 MV plans computed with convolution superposition algorithm on Pinnacle treatment planning system.

  15. Dosimetry audit of radiotherapy treatment planning systems.

    Science.gov (United States)

    Bulski, Wojciech; Chełmiński, Krzysztof; Rostkowska, Joanna

    2015-07-01

    In radiotherapy Treatment Planning Systems (TPS) various calculation algorithms are used. The accuracy of dose calculations has to be verified. Numerous phantom types, detectors and measurement methodologies are proposed to verify the TPS calculations with dosimetric measurements. A heterogeneous slab phantom has been designed within a Coordinated Research Project (CRP) of the IAEA. The heterogeneous phantom was developed in the frame of the IAEA CRP. The phantom consists of frame slabs made with polystyrene and exchangeable inhomogeneity slabs equivalent to bone or lung tissue. Special inserts allow to position thermoluminescent dosimeters (TLD) capsules within the polystyrene slabs below the bone or lung equivalent slabs and also within the lung equivalent material. Additionally, there are inserts that allow to position films or ionisation chamber in the phantom. Ten Polish radiotherapy centres (of 30 in total) were audited during on-site visits. Six different TPSs and five calculation algorithms were examined in the presence of inhomogeneities. Generally, most of the results from TLD were within 5 % tolerance. Differences between doses calculated by TPSs and measured with TLD did not exceed 4 % for bone and polystyrene equivalent materials. Under the lung equivalent material, on the beam axis the differences were lower than 5 %, whereas inside the lung equivalent material, off the beam axis, in some cases they were of around 7 %. The TLD results were confirmed with the ionisation chamber measurements. The comparison results of the calculations and the measurements allow to detect limitations of TPS calculation algorithms. The audits performed with the use of heterogeneous phantom and TLD seem to be an effective tool for detecting the limitations in the TPS performance or beam configuration errors at audited radiotherapy departments. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Comparison of dose calculation algorithms for treatment planning in external photon beam therapy for clinical situations

    Science.gov (United States)

    Knöös, Tommy; Wieslander, Elinore; Cozzi, Luca; Brink, Carsten; Fogliata, Antonella; Albers, Dirk; Nyström, Håkan; Lassen, Søren

    2006-11-01

    A study of the performance of five commercial radiotherapy treatment planning systems (TPSs) for common treatment sites regarding their ability to model heterogeneities and scattered photons has been performed. The comparison was based on CT information for prostate, head and neck, breast and lung cancer cases. The TPSs were installed locally at different institutions and commissioned for clinical use based on local procedures. For the evaluation, beam qualities as identical as possible were used: low energy (6 MV) and high energy (15 or 18 MV) x-rays. All relevant anatomical structures were outlined and simple treatment plans were set up. Images, structures and plans were exported, anonymized and distributed to the participating institutions using the DICOM protocol. The plans were then re-calculated locally and exported back for evaluation. The TPSs cover dose calculation techniques from correction-based equivalent path length algorithms to model-based algorithms. These were divided into two groups based on how changes in electron transport are accounted for ((a) not considered and (b) considered). Increasing the complexity from the relatively homogeneous pelvic region to the very inhomogeneous lung region resulted in less accurate dose distributions. Improvements in the calculated dose have been shown when models consider volume scatter and changes in electron transport, especially when the extension of the irradiated volume was limited and when low densities were present in or adjacent to the fields. A Monte Carlo calculated algorithm input data set and a benchmark set for a virtual linear accelerator have been produced which have facilitated the analysis and interpretation of the results. The more sophisticated models in the type b group exhibit changes in both absorbed dose and its distribution which are congruent with the simulations performed by Monte Carlo-based virtual accelerator.

  17. Tissue classifications in Monte Carlo simulations of patient dose for photon beam tumor treatments

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Mu-Han [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, 101 Sec. 2, Kung Fu Road, Hsinchu 30013, Taiwan (China); Chao, Tsi-Chian [Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Lee, Chung-Chi [Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Department of Radiation Oncology, Chang Gung Memorial Hospital, 5 Fu-Hsin Street, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Tung-Chieh Chang, Joseph [Department of Radiation Oncology, Chang Gung Memorial Hospital, 5 Fu-Hsin Street, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Tung, Chuan-Jong, E-mail: cjtung@mail.cgu.edu.t [Department of Medical Imaging and Radiological Sciences, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan (China)

    2010-07-21

    The purpose of this work was to study the calculated dose uncertainties induced by the material classification that determined the interaction cross-sections and the water-to-material stopping-power ratios. Calculations were made for a head- and neck-cancer patient treated with five intensity-modulated radiotherapy fields using 6 MV photon beams. The patient's CT images were reconstructed into two voxelized patient phantoms based on different CT-to-material classification schemes. Comparisons of the depth-dose curve of the anterior-to-posterior field and the dose-volume-histogram of the treatment plan were used to evaluate the dose uncertainties from such schemes. The results indicated that any misassignment of tissue materials could lead to a substantial dose difference, which would affect the treatment outcome. To assure an appropriate material assignment, it is desirable to have different conversion tables for various parts of the body. The assignment of stopping-power ratio should be based on the chemical composition and the density of the material.

  18. Tissue classifications in Monte Carlo simulations of patient dose for photon beam tumor treatments

    International Nuclear Information System (INIS)

    Lin, Mu-Han; Chao, Tsi-Chian; Lee, Chung-Chi; Tung-Chieh Chang, Joseph; Tung, Chuan-Jong

    2010-01-01

    The purpose of this work was to study the calculated dose uncertainties induced by the material classification that determined the interaction cross-sections and the water-to-material stopping-power ratios. Calculations were made for a head- and neck-cancer patient treated with five intensity-modulated radiotherapy fields using 6 MV photon beams. The patient's CT images were reconstructed into two voxelized patient phantoms based on different CT-to-material classification schemes. Comparisons of the depth-dose curve of the anterior-to-posterior field and the dose-volume-histogram of the treatment plan were used to evaluate the dose uncertainties from such schemes. The results indicated that any misassignment of tissue materials could lead to a substantial dose difference, which would affect the treatment outcome. To assure an appropriate material assignment, it is desirable to have different conversion tables for various parts of the body. The assignment of stopping-power ratio should be based on the chemical composition and the density of the material.

  19. Implant Dentistry in General Practice Part 2: Treatment Planning.

    Science.gov (United States)

    Nicholson, Ken

    2016-01-01

    This paper, the second of a series of two, provides an introduction to treatment planning in implant dentistry for the general dental practitioner. Clinical relevance: Appropriate training has made implant placement and restoration a routine treatment option in general practice.

  20. Energy modulated electron therapy: Design, implementation, and evaluation of a novel method of treatment planning and delivery

    Science.gov (United States)

    Al-Yahya, Khalid

    Energy modulated electron therapy (EMET) is a promising treatment modality that has the fundamental capabilities to enhance the treatment planning and delivery of superficially located targets. Although it offers advantages over x-ray intensity modulated radiation therapy (IMRT), EMET has not been widely implemented to the same level of accuracy, automation, and clinical routine as its x-ray counterpart. This lack of implementation is attributed to the absence of a remotely automated beam shaping system as well as the deficiency in dosimetric accuracy of clinical electron pencil beam algorithms in the presence of beam modifiers and tissue heterogeneities. In this study, we present a novel technique for treatment planning and delivery of EMET. The delivery is achieved using a prototype of an automated "few leaf electron collimator" (FLEC). It consists of four copper leaves driven by stepper motors which are synchronized with the x-ray jaws in order to form a series of collimated rectangular openings or "fieldlets". Based on Monte Carlo studies, the FLEC has been designed to serve as an accessory tool to the current accelerator equipment. The FLEC was constructed and its operation was fully automated and integrated with the accelerator through an in-house assembled control unit. The control unit is a portable computer system accompanied with customized software that delivers EMET plans after acquiring them from the optimization station. EMET plans are produced based on dose volume constraints that employ Monte Carlo pre-generated and patient-specific kernels which are utilized by an in-house developed optimization algorithm. The structure of the optimization software is demonstrated. Using Monte Carlo techniques to calculate dose allows for accurate modeling of the collimation system as well as the patient heterogeneous geometry and take into account their impact on optimization. The Monte Carlo calculations were validated by comparing them against output

  1. Matlab Tools: An Alternative to Planning Systems in Brachytherapy Treatments

    International Nuclear Information System (INIS)

    Herrera, Higmar; Rodriguez, Mercedes; Rodriguez, Miguel

    2006-01-01

    This work proposes the use of the Matlab environment to obtain the treatment dose based on the reported data by Krishnaswamy and Liu et al. The comparison with reported measurements is showed for the Amersham source model. For the 3M source model, measurements with TLDs and a Monte Carlo simulation are compared to the data obtained by Matlab. The difference for the Amersham model is well under the 15% recommended by the IAEA and for the 3M model, although the difference is greater, the results are consistent. The good agreement to the reported data allows the Matlab calculations to be used in daily brachytherapy treatments

  2. 2: Local area networks as a multiprocessor treatment planning system

    International Nuclear Information System (INIS)

    Neblett, D.L.; Hogan, S.E.

    1987-01-01

    The creation of a local area network (LAN) of interconnected computers provides an environment of multi computer processors that adds a new dimension to treatment planning. A LAN system provides the opportunity to have two or more computers working on the plan in parallel. With high speed interprocessor transfer, events such as the time consuming task of correcting several individual beams for contours and inhomogeneities can be performed simultaneously; thus, effectively creating a parallel multiprocessor treatment planning system

  3. Nitrate Waste Treatment Sampling and Analysis Plan

    Energy Technology Data Exchange (ETDEWEB)

    Vigil-Holterman, Luciana R. [Los Alamos National Laboratory; Martinez, Patrick Thomas [Los Alamos National Laboratory; Garcia, Terrence Kerwin [Los Alamos National Laboratory

    2017-07-05

    This plan is designed to outline the collection and analysis of nitrate salt-bearing waste samples required by the New Mexico Environment Department- Hazardous Waste Bureau in the Los Alamos National Laboratory (LANL) Hazardous Waste Facility Permit (Permit).

  4. Accuracy of computerized radiation treatment planning

    International Nuclear Information System (INIS)

    Vayrynen, T.; Kiviniitty, K.; Taskinen, P.J.

    1979-01-01

    The accuracy of computerized dose planning depends essentially on the computer program. The quickest and simplest way to assess the accuracy of a commercial program is to compare the results of the computer calculations with measured values. The present report deals with the accuracy of the RADPLAN dose planning in different situations easy to control. The test methods are also applicable to other corresponding systems. (Auth.)

  5. The Trimeric Model: A New Model of Periodontal Treatment Planning

    Science.gov (United States)

    Tarakji, Bassel

    2014-01-01

    Treatment of periodontal disease is a complex and multidisciplinary procedure, requiring periodontal, surgical, restorative, and orthodontic treatment modalities. Several authors attempted to formulate models for periodontal treatment that orders the treatment steps in a logical and easy to remember manner. In this article, we discuss two models of periodontal treatment planning from two of the most well-known textbook in the specialty of periodontics internationally. Then modify them to arrive at a new model of periodontal treatment planning, The Trimeric Model. Adding restorative and orthodontic interrelationships with periodontal treatment allows us to expand this model into the Extended Trimeric Model of periodontal treatment planning. These models will provide a logical framework and a clear order of the treatment of periodontal disease for general practitioners and periodontists alike. PMID:25177662

  6. 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.

  7. Automated construction of an intraoperative high-dose-rate treatment plan library for the Varian brachytherapy treatment planning system.

    Science.gov (United States)

    Deufel, Christopher L; Furutani, Keith M; Dahl, Robert A; Haddock, Michael G

    2016-01-01

    The ability to create treatment plans for intraoperative high-dose-rate (IOHDR) brachytherapy is limited by lack of imaging and time constraints. An automated method for creation of a library of high-dose-rate brachytherapy plans that can be used with standard planar applicators in the intraoperative setting is highly desirable. Nonnegative least squares algebraic methods were used to identify dwell time values for flat, rectangular planar applicators. The planar applicators ranged in length and width from 2 cm to 25 cm. Plans were optimized to deliver an absorbed dose of 10 Gy to three different depths from the patient surface: 0 cm, 0.5 cm, and 1.0 cm. Software was written to calculate the optimized dwell times and insert dwell times and positions into a .XML plan template that can be imported into the Varian brachytherapy treatment planning system. The user may import the .XML template into the treatment planning system in the intraoperative setting to match the patient applicator size and prescribed treatment depth. A total of 1587 library plans were created for IOHDR brachytherapy. Median plan generation time was approximately 1 minute per plan. Plan dose was typically 100% ± 1% (mean, standard deviation) of the prescribed dose over the entire length and width of the applicator. Plan uniformity was best for prescription depths of 0 cm and 0.5 cm from the patient surface. An IOHDR plan library may be created using automated methods. Thousands of plan templates may be optimized and prepared in a few hours to accommodate different applicator sizes and treatment depths and reduce treatment planning time. The automated method also enforces dwell time symmetry for symmetrical applicator geometries, which simplifies quality assurance. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. Virtual reality image applications for treatment planning in prosthodontic dentistry.

    Science.gov (United States)

    Ogawa, Takumi; Ikawa, Tomoko; Shigeta, Yuko; Kasama, Shintaro; Ando, Eriko; Fukushima, Shunji; Hattori, Asaki; Suzuki, Naoki

    2011-01-01

    For successful occlusal reconstruction, the prosthodontists must take several points into consideration, such as those involving issues with functional and morphological findings and aesthetics. They then must unify this information into a coherent treatment plan. In this present study we focused on prosthodontic treatment and investigated how treatment planning and simulation could be applied to two cases. The personal occlusion condition can be reproduced on the virtual articulator in VR space. In addition, various simulations can be performed that involve prosthetesis design.

  9. 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

  10. Manpower Planning for Wastewater Treatment Plants.

    Science.gov (United States)

    Davies, J. Kenneth; And Others

    This document discusses the components necessary in the development of a forecasting process by which manpower needs can be determined and the development of action programs by which the projected needs may be satisfied. The primary focus of this manual is directed at that person in a state agency who has the responsibility for planning the…

  11. Radiographic stents: integrating treatment planning and implant placement.

    Science.gov (United States)

    De Kok, Ingeborg J; Thalji, Ghadeer; Bryington, Matthew; Cooper, Lyndon F

    2014-01-01

    The pivotal point in treatment planning for dental implants occurs when the location of bone is viewed radiographically in the context of the planned prosthesis. Radiographic planning for dental implant therapy should be used only after a review of the patient's systemic health, imaging history, oral health, and local oral conditions. The radiological diagnostic and planning procedure for dental implants can only be fully achieved with the use of a well-designed and -constructed radiographic guide. This article reviews several methods for construction of radiographic guides and how they may be utilized for improving implant surgery planning and performance. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Photon beam modelling with Pinnacle3 Treatment Planning System for a Rokus M Co-60 Machine

    International Nuclear Information System (INIS)

    Dulcescu, Mihaela; Murgulet Cristian

    2008-01-01

    The basic relationships of the convolution/superposition dose calculation technique are reviewed, and a modelling technique that can be used for obtaining a satisfactory beam model for a commercially available convolution/superposition-based treatment planning system is described. A fluence energy spectrum for a Co-60 treatment machine obtained from a Monte Carlo simulation was used for modelling the fluence spectrum for a Rokus M machine. In order to achieve this model we measured the depth dose distribution and the dose profiles with a Wellhofer dosimetry system. The primary fluence was iteratively modelled by comparing the computed depth dose curves and beam profiles with the depth dose curves and crossbeam profiles measured in a water phantom. The objective of beam modelling is to build a model of the primary fluence that the patient is exposed to, which can then be used for the calculation of the dose deposited in the patient. (authors)

  13. Automated treatment planning engine for prostate seed implant brachytherapy

    International Nuclear Information System (INIS)

    Yu Yan; Zhang, J.B.Y.; Brasacchio, Ralph A.; Okunieff, Paul G.; Rubens, Deborah J.; Strang, John G.; Soni, Arvind; Messing, Edward M.

    1999-01-01

    Purpose: To develop a computer-intelligent planning engine for automated treatment planning and optimization of ultrasound- and template-guided prostate seed implants. Methods and Materials: The genetic algorithm was modified to reflect the 2D nature of the implantation template. A multi-objective decision scheme was used to rank competing solutions, taking into account dose uniformity and conformity to the planning target volume (PTV), dose-sparing of the urethra and the rectum, and the sensitivity of the resulting dosimetry to seed misplacement. Optimized treatment plans were evaluated using selected dosimetric quantifiers, dose-volume histogram (DVH), and sensitivity analysis based on simulated seed placement errors. These dosimetric planning components were integrated into the Prostate Implant Planning Engine for Radiotherapy (PIPER). Results: PIPER has been used to produce a variety of plans for prostate seed implants. In general, maximization of the minimum peripheral dose (mPD) for given implanted total source strength tended to produce peripherally weighted seed patterns. Minimization of the urethral dose further reduced the loading in the central region of the PTV. Isodose conformity to the PTV was achieved when the set of objectives did not reflect seed positioning uncertainties; the corresponding optimal plan generally required fewer seeds and higher source strength per seed compared to the manual planning experience. When seed placement uncertainties were introduced into the set of treatment planning objectives, the optimal plan tended to reach a compromise between the preplanned outcome and the likelihood of retaining the preferred outcome after implantation. The reduction in the volatility of such seed configurations optimized under uncertainty was verified by sensitivity studies. Conclusion: An automated treatment planning engine incorporating real-time sensitivity analysis was found to be a useful tool in dosimetric planning for prostate

  14. Automated treatment planning engine for prostate seed implant brachytherapy.

    Science.gov (United States)

    Yu, Y; Zhang, J B; Brasacchio, R A; Okunieff, P G; Rubens, D J; Strang, J G; Soni, A; Messing, E M

    1999-02-01

    To develop a computer-intelligent planning engine for automated treatment planning and optimization of ultrasound- and template-guided prostate seed implants. The genetic algorithm was modified to reflect the 2D nature of the implantation template. A multi-objective decision scheme was used to rank competing solutions, taking into account dose uniformity and conformity to the planning target volume (PTV), dose-sparing of the urethra and the rectum, and the sensitivity of the resulting dosimetry to seed misplacement. Optimized treatment plans were evaluated using selected dosimetric quantifiers, dose-volume histogram (DVH), and sensitivity analysis based on simulated seed placement errors. These dosimetric planning components were integrated into the Prostate Implant Planning Engine for Radiotherapy (PIPER). PIPER has been used to produce a variety of plans for prostate seed implants. In general, maximization of the minimum peripheral dose (mPD) for given implanted total source strength tended to produce peripherally weighted seed patterns. Minimization of the urethral dose further reduced the loading in the central region of the PTV. Isodose conformity to the PTV was achieved when the set of objectives did not reflect seed positioning uncertainties; the corresponding optimal plan generally required fewer seeds and higher source strength per seed compared to the manual planning experience. When seed placement uncertainties were introduced into the set of treatment planning objectives, the optimal plan tended to reach a compromise between the preplanned outcome and the likelihood of retaining the preferred outcome after implantation. The reduction in the volatility of such seed configurations optimized under uncertainty was verified by sensitivity studies. An automated treatment planning engine incorporating real-time sensitivity analysis was found to be a useful tool in dosimetric planning for prostate brachytherapy.

  15. Treatment plan complexity metrics for predicting IMRT pre-treatment quality assurance results.

    Science.gov (United States)

    Crowe, S B; Kairn, T; Kenny, J; Knight, R T; Hill, B; Langton, C M; Trapp, J V

    2014-09-01

    The planning of IMRT treatments requires a compromise between dose conformity (complexity) and deliverability. This study investigates established and novel treatment complexity metrics for 122 IMRT beams from prostate treatment plans. The Treatment and Dose Assessor software was used to extract the necessary data from exported treatment plan files and calculate the metrics. For most of the metrics, there was strong overlap between the calculated values for plans that passed and failed their quality assurance (QA) tests. However, statistically significant variation between plans that passed and failed QA measurements was found for the established modulation index and for a novel metric describing the proportion of small apertures in each beam. The 'small aperture score' provided threshold values which successfully distinguished deliverable treatment plans from plans that did not pass QA, with a low false negative rate.

  16. Inverse treatment planning based on MRI for HDR prostate brachytherapy

    International Nuclear Information System (INIS)

    Citrin, Deborah; Ning, Holly; Guion, Peter; Li Guang; Susil, Robert C.; Miller, Robert W.; Lessard, Etienne; Pouliot, Jean; Xie Huchen; Capala, Jacek; Coleman, C. Norman; Camphausen, Kevin; Menard, Cynthia

    2005-01-01

    Purpose: To develop and optimize a technique for inverse treatment planning based solely on magnetic resonance imaging (MRI) during high-dose-rate brachytherapy for prostate cancer. Methods and materials: Phantom studies were performed to verify the spatial integrity of treatment planning based on MRI. Data were evaluated from 10 patients with clinically localized prostate cancer who had undergone two high-dose-rate prostate brachytherapy boosts under MRI guidance before and after pelvic radiotherapy. Treatment planning MRI scans were systematically evaluated to derive a class solution for inverse planning constraints that would reproducibly result in acceptable target and normal tissue dosimetry. Results: We verified the spatial integrity of MRI for treatment planning. MRI anatomic evaluation revealed no significant displacement of the prostate in the left lateral decubitus position, a mean distance of 14.47 mm from the prostatic apex to the penile bulb, and clear demarcation of the neurovascular bundles on postcontrast imaging. Derivation of a class solution for inverse planning constraints resulted in a mean target volume receiving 100% of the prescribed dose of 95.69%, while maintaining a rectal volume receiving 75% of the prescribed dose of <5% (mean 1.36%) and urethral volume receiving 125% of the prescribed dose of <2% (mean 0.54%). Conclusion: Systematic evaluation of image spatial integrity, delineation uncertainty, and inverse planning constraints in our procedure reduced uncertainty in planning and treatment

  17. Comparison of absorbed dose in the cervix carcinoma therapy by brachytherapy of high dose rate using the conventional planning and Monte Carlo simulation; Comparacao da dose absorvida no tratamento do cancer ginecologico por braquiterapia de alta taxa de dose utilizando o planejamento convencional do tratamento e simulacao de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Aneli Oliveira da

    2010-07-01

    This study aims to compare the doses received for patients submitted to brachytherapy High Dose Rate (HDR) brachytherapy, a method of treatment of the cervix carcinoma, performed in the planning system PLATO BPS with the doses obtained by Monte Carlo simulation using the radiation transport code MCNP 5 and one female anthropomorphic phantom based on voxel, the FAX. The implementation of HDR brachytherapy treatment for the cervix carcinoma consists of the insertion of an intrauterine probe and an intravaginal probe (ring or ovoid) and then two radiographs are obtained, anteroposterior (AP) and lateral (LAT) to confirm the position of the applicators in the patient and to allow the treatment planning and the determination of the absorbed dose at points of interest: rectum, bladder, sigmoid and point A, which corresponds anatomically to the crossings of the uterine arteries with ureters The absorbed doses obtained with the code MCNP 5, with the exception of the absorbed dose in the rectum and sigmoid for the simulation considering a point source of {sup 192}Ir, are lower than the absorbed doses from PLATO BPS calculations because the MCNP 5 considers the chemical compositions and densities of FAX body, not considering the medium as water. When considering the Monte Carlo simulation for a source with dimensions equal to that used in the brachytherapy irradiator used in this study, the values of calculated absorbed dose to the bladder, to the rectum, to the right point A and to the left point A were respectively lower than those determined by the treatment planning system in 33.29, 5.01, 22.93 and 19.04%. These values are almost all larger than the maximum acceptable deviation between patient planned and administered doses (5 %). With regard to the rectum and bladder, which are organs that must be protected, the present results are in favor of the radiological protection of patients. The point A, that is on the isodose of 100%, used to tumor treatment, the results

  18. Proposed Site Treatment Plan (PSTP). STP reference document

    International Nuclear Information System (INIS)

    1995-01-01

    The Department of Energy (DOE) is required by Section 3021(b) of the Resource Conservation and Recovery Act (RCRA), as amended by the Federal Facility Compliance Act (FFCAct), to prepare a plan describing the development of treatment capacities and technologies for treating mixed waste (hazardous/radioactive waste). DOE decided to prepare its site treatment plan in a three phased approach. The first phase, called the Conceptual Site Treatment Plan (CSTP), was issued in October 1993. At the Savannah River Site (SRS) the CSTP described mixed waste streams generated at SRS and listed treatment scenarios for each waste stream utilizing an onsite, offsite DOE, and offsite or onsite commercial or vendor treatment option. The CSTP is followed by the Draft Site Treatment Plan (DSTP), due to be issued in August 1994. The DSTP, the current activity., will narrow the options discussed in the CSTP to a preferred treatment option, if possible, and will include waste streams proposed to be shipped to SRS from other DOE facilities as well as waste streams SRS may send offsite for treatment. The SRS DSTP process has been designed to address treatment options for each of the site's mixed waste streams. The SRS Proposed Site Treatment Plan (PSTP) is due to be issued in February 1995. The compliance order would be derived from the PSTP

  19. Treatment planning considerations in contrast-enhanced radiotherapy: energy and beam aperture optimization

    Energy Technology Data Exchange (ETDEWEB)

    Garnica-Garza, H M, E-mail: hgarnica@cinvestav.mx [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional Unidad Monterrey, Via del Conocimiento 201 Parque de Investigacion e Innovacion Tecnologica, Apodaca NL CP 66600 (Mexico)

    2011-01-21

    It has been shown that the use of kilovoltage x-rays in conjunction with a contrast agent incorporated into the tumor can lead to acceptable treatment plans with regard to the absorbed dose distribution produced in the target as well as in the tissue and organs at risk surrounding it. In this work, several key aspects related to the technology and irradiation techniques necessary to clinically implement this treatment modality are addressed by means of Monte Carlo simulation. The Zubal phantom was used to model a prostate radiotherapy treatment, a challenging site due to the depth of the prostate and the presence of bony structures that must be traversed by the x-ray beam on its way to the target. It is assumed that the concentration levels of the enhancing agent present in the tumor are at or below 10 mg per 1 g of tissue. The Monte Carlo code PENELOPE was used to model a commercial x-ray tube having a tungsten target. X-ray energy spectra for several combinations of peak electron energy and added filtration were obtained. For each energy spectrum, a treatment plan was calculated, with the PENELOPE Monte Carlo code, by modeling the irradiation of the patient as 72 independent conformal beams distributed at intervals of 5{sup 0} around the phantom in order to model a full x-ray source rotation. The Cimmino optimization algorithm was then used to find the optimum beam weight and energy for different treatment strategies. It is shown that for a target dose prescription of 72 Gy covering the whole tumor, the maximum rectal wall and bladder doses are kept below 52 Gy for the largest concentration of contrast agent of 10 mg per 1 g of tissue. It is also shown that concentrations of as little as 5 mg per 1 g of tissue also render dose distributions with excellent sparing of the organs at risk. A treatment strategy to address the presence of non-uniform distributions of the contrast agent in the target is also modeled and discussed.

  20. Monte Carlo dose calculations for BNCT treatment of diffuse human lung tumours

    International Nuclear Information System (INIS)

    Altieri, S.; Bortolussi, S.; Bruschi, P.

    2006-01-01

    In order to test the possibility to apply BNCT in the core of diffuse lung tumours, dose distribution calculations were made. The simulations were performed with the Monte Carlo code MCNP.4c2, using the male computational phantom Adam, version 07/94. Volumes of interest were voxelized for the tally requests, and results were obtained for tissues with and without Boron. Different collimated neutron sources were tested in order to establish the proper energies, as well as single and multiple beams to maximize neutron flux uniformity inside the target organs. Flux and dose distributions are reported. The use of two opposite epithermal neutron collimated beams insures good levels of dose homogeneity inside the lungs, with a substantially lower radiation dose delivered to surrounding structures. (author)

  1. Conversion of helical tomotherapy plans to step-and-shoot IMRT plans--Pareto front evaluation of plans from a new treatment planning system.

    Science.gov (United States)

    Petersson, Kristoffer; Ceberg, Crister; Engström, Per; Benedek, Hunor; Nilsson, Per; Knöös, Tommy

    2011-06-01

    The resulting plans from a new type of treatment planning system called SharePlan have been studied. This software allows for the conversion of treatment plans generated in a TomoTherapy system for helical delivery, into plans deliverable on C-arm linear accelerators (linacs), which is of particular interest for clinics with a single TomoTherapy unit. The purpose of this work was to evaluate and compare the plans generated in the SharePlan system with the original TomoTherapy plans and with plans produced in our clinical treatment planning system for intensity-modulated radiation therapy (IMRT) on C-arm linacs. In addition, we have analyzed how the agreement between SharePlan and TomoTherapy plans depends on the number of beams and the total number of segments used in the optimization. Optimized plans were generated for three prostate and three head-and-neck (H&N) cases in the TomoTherapy system, and in our clinical treatment planning systems (TPS) used for IMRT planning with step-and-shoot delivery. The TomoTherapy plans were converted into step-and-shoot IMRT plans in SharePlan. For each case, a large number of Pareto optimal plans were created to compare plans generated in SharePlan with plans generated in the Tomotherapy system and in the clinical TPS. In addition, plans were generated in SharePlan for the three head-and-neck cases to evaluate how the plan quality varied with the number of beams used. Plans were also generated with different number of beams and segments for other patient cases. This allowed for an evaluation of how to minimize the number of required segments in the converted IMRT plans without compromising the agreement between them and the original TomoTherapy plans. The plans made in SharePlan were as good as or better than plans from our clinical system, but they were not as good as the original TomoTherapy plans. This was true for both the head-and-neck and the prostate cases, although the differences between the plans for the latter were

  2. SU-E-T-56: Brain Metastasis Treatment Plans for Contrast-Enhanced Synchrotron Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Obeid, L; Adam, J [Grenoble Institut des Neurosciences, La Tronche, Rhone-Alpes (France); Tessier, A [Centre Hospitalier Universitaire, La Tronche, Rhone-Alpes (France); Vautrin, M; Benkebil, M [DOSIsoft, Cachan, Ile de France (France); Sihanath, R [Centre Hospitalier Universitaire, La Tronche, Rhone- Alpes (France)

    2014-06-01

    Purpose: Iodine-enhanced radiotherapy is an innovative treatment combining the selective accumulation of an iodinated contrast agent in brain tumors with irradiations using monochromatic medium energy x-rays. The aim of this study is to compare dynamic stereotactic arc-therapy and iodineenhanced SSRT. Methods: Five patients bearing brain metastasis received a standard helical 3D-scan without iodine. A second scan was acquired 13 min after an 80 g iodine infusion. Two SSRT treatment plans (with/without iodine) were performed for each patient using a dedicated Monte Carlo (MC) treatment planning system (TPS) based on the ISOgray TPS. Ten coplanar beams (6×6 cm2, shaped with collimator) were simulated. MC statistical error objective was less than 5% in the 50% isodose. The dynamic arc-therapy plan was achieved on the Iplan Brainlab TPS. The treatment plan validation criteria were fixed such that 100% of the prescribed dose is delivered at the beam isocentre and the 70% isodose contains the whole target volume. The comparison elements were the 70% isodose volume, the average and maximum doses delivered to organs at risk (OAR): brainstem, optical nerves, chiasma, eyes, skull bone and healthy brain parenchyma. Results: The stereotactic dynamic arc-therapy remains the best technique in terms of dose conformation. Iodine-enhanced SSRT presents similar performances to dynamic arc-therapy with increased brainstem and brain parenchyma sparing. One disadvantage of SSRT is the high dose to the skull bone. Iodine accumulation in metastasis may increase the dose by 20–30%, allowing a normal tissue sparing effect at constant prescribed dose. Treatment without any iodine enhancement (medium-energy stereotactic radiotherapy) is not relevant with degraded HDVs (brain, parenchyma and skull bone) comparing to stereotactic dynamic arc-therapy. Conclusion: Iodine-enhanced SSRT exhibits a good potential for brain metastasis treatment regarding the dose distribution and OAR criteria.

  3. Experimental and Monte Carlo-based determination of the beam quality specifier for TomoTherapyHD treatment units.

    Science.gov (United States)

    Howitz, S; Schwedas, M; Wiezorek, T; Zink, K

    2017-10-12

    Reference dosimetry by means of clinical linear accelerators in high-energy photon fields requires the determination of the beam quality specifier TPR 20,10 , which characterizes the relative particle flux density of the photon beam. The measurement of TPR 20,10 has to be performed in homogenous photon beams of size 10×10cm 2 with a focus-detector distance of 100cm. These requirements cannot be fulfilled by TomoTherapy treatment units from Accuray. The TomoTherapy unit provides a flattening-filter-free photon fan beam with a maximum field width of 40cm and field lengths of 1.0cm, 2.5cm and 5.0cm at a focus-isocenter distance of 85cm. For the determination of the beam quality specifier from measurements under nonstandard reference conditions Sauer and Palmans proposed experiment-based fit functions. Moreover, Sauer recommends considering the impact of the flattening-filter-free beam on the measured data. To verify these fit functions, in the present study a Monte Carlo based model of the treatment head of a TomoTherapyHD unit was designed and commissioned with existing beam data of our clinical TomoTherapy machine. Depth dose curves and dose profiles were in agreement within 1.5% between experimental and Monte Carlo-based data. Based on the fit functions from Sauer and Palmans the beam quality specifier TPR 20,10 was determined from field sizes 5×5cm 2 , 10×5cm 2 , 20×5cm 2 and 40×5cm 2 based on dosimetric measurements and Monte Carlo simulations. The mean value from all experimental values of TPR 20,10 resulted in TPR 20,10 ¯=0.635±0.4%. The impact of the non-homogenous field due to the flattening-filter-free beam was negligible for field sizes below 20×5cm 2 . The beam quality specifier calculated by Monte Carlo simulations was TPR 20,10 =0.628 and TPR 20,10 =0.631 for two different calculation methods. The stopping power ratio water-to-air s w,a Δ directly depends on the beam quality specifier. The value determined from all experimental TPR 20,10 data

  4. Planning for the radwaste treatment facility operation

    International Nuclear Information System (INIS)

    Park, H.H.; Han, K.W.; Kim, J.H.

    1985-04-01

    In accordance with treatment of radioactive wastes from normal operation of PIEF and nuclear fuel fabrication facilities, institutions using RI, of spent fuel from nuclear power plants, the operation of RWTF is requested. Therefore the objective is to treat the radioactive wastes safely by the treatment techniques accmulated through research experiences of many years, to minimize the effect to environments and inhabitants, to establish the operation program to perform the facilities management effectively and reasonably. (Author)

  5. A preliminary Monte Carlo study for the treatment head of a carbon-ion radiotherapy facility using TOPAS

    Science.gov (United States)

    Liu, Hongdong; Zhang, Lian; Chen, Zhi; Liu, Xinguo; Dai, Zhongying; Li, Qiang; Xu, Xie George

    2017-09-01

    In medical physics it is desirable to have a Monte Carlo code that is less complex, reliable yet flexible for dose verification, optimization, and component design. TOPAS is a newly developed Monte Carlo simulation tool which combines extensive radiation physics libraries available in Geant4 code, easyto-use geometry and support for visualization. Although TOPAS has been widely tested and verified in simulations of proton therapy, there has been no reported application for carbon ion therapy. To evaluate the feasibility and accuracy of TOPAS simulations for carbon ion therapy, a licensed TOPAS code (version 3_0_p1) was used to carry out a dosimetric study of therapeutic carbon ions. Results of depth dose profile based on different physics models have been obtained and compared with the measurements. It is found that the G4QMD model is at least as accurate as the TOPAS default BIC physics model for carbon ions, but when the energy is increased to relatively high levels such as 400 MeV/u, the G4QMD model shows preferable performance. Also, simulations of special components used in the treatment head at the Institute of Modern Physics facility was conducted to investigate the Spread-Out dose distribution in water. The physical dose in water of SOBP was found to be consistent with the aim of the 6 cm ridge filter.

  6. Towards biology-oriented treatment planning in hadrontherapy

    Czech Academy of Sciences Publication Activity Database

    Kundrát, Pavel

    2006-01-01

    Roč. 122, 1-4 (2006), s. 480-482 ISSN 0144-8420 R&D Projects: GA ČR GA202/05/2728 Institutional research plan: CEZ:AV0Z10100502 Keywords : treatment planning * hadron radiotherapy Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.446, year: 2006

  7. 300 Area waste acid treatment system closure plan. Revision 1

    International Nuclear Information System (INIS)

    1996-03-01

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan

  8. The influence of cephalometrics on orthodontic treatment planning

    NARCIS (Netherlands)

    Nijkamp, P.G.; Habets, L.L.M.H.; Aartman, I.H.A.; Zentner, A.

    2008-01-01

    SUMMARY Since its introduction, cephalometrics, i.e. cephalometric radiography and analysis, has been used for orthodontic treatment planning. However, the effectiveness of this diagnostic method remains questionable. A randomized crossover study was designed to assess the infl uence of

  9. 300 Area waste acid treatment system closure plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan.

  10. "SABER": A new software tool for radiotherapy treatment plan evaluation.

    Science.gov (United States)

    Zhao, Bo; Joiner, Michael C; Orton, Colin G; Burmeister, Jay

    2010-11-01

    Both spatial and biological information are necessary in order to perform true optimization of a treatment plan and for predicting clinical outcome. The goal of this work is to develop an enhanced treatment plan evaluation tool which incorporates biological parameters and retains spatial dose information. A software system is developed which provides biological plan evaluation with a novel combination of features. It incorporates hyper-radiosensitivity using the induced-repair model and applies the new concept of dose convolution filter (DCF) to simulate dose wash-out effects due to cell migration, bystander effect, and/or tissue motion during treatment. Further, the concept of spatial DVH (sDVH) is introduced to evaluate and potentially optimize the spatial dose distribution in the target volume. Finally, generalized equivalent uniform dose is derived from both the physical dose distribution (gEUD) and the distribution of equivalent dose in 2 Gy fractions (gEUD2) and the software provides three separate models for calculation of tumor control probability (TCP), normal tissue complication probability (NTCP), and probability of uncomplicated tumor control (P+). TCP, NTCP, and P+ are provided as a function of prescribed dose and multivariable TCP, NTCP, and P+ plots are provided to illustrate the dependence on individual parameters used to calculate these quantities. Ten plans from two clinical treatment sites are selected to test the three calculation models provided by this software. By retaining both spatial and biological information about the dose distribution, the software is able to distinguish features of radiotherapy treatment plans not discernible using commercial systems. Plans that have similar DVHs may have different spatial and biological characteristics and the application of novel tools such as sDVH and DCF within the software may substantially change the apparent plan quality or predicted plan metrics such as TCP and NTCP. For the cases examined

  11. Coordination systems for three-dimension radiation treatment planning

    International Nuclear Information System (INIS)

    Yang Dailun; Wu Zhangwen; Luo Zhengming

    2004-01-01

    This paper describes the coordination systems of a three dimension radiation treatment plan. The coordination systems refer to the body coordination, the isocenter coordination and the beam coordination. The authors have derived the analytical equations for coordination transforms, indicated the applications of the coordination systems, and provided corresponding treating means. With strict construction and perfect structure, the systems have an important significance for increasing the whole capability of a three dimension radiation treatment plan, and can be extensively and flexibly used. (authors)

  12. Monte Carlo simulation of gynecologic brachytherapy treatment of high rate considering the heterogeneity; Simulacion Monte Carlo de un tratamiento de braquiterapia ginecologica de alta tasa teniendo en cuenta las heterogeneidades

    Energy Technology Data Exchange (ETDEWEB)

    Berenguer Serrano, R.; Rivera Jimenez, M.; Nunez Quintanilla, A. T.; Vara Olivas, V. de la; Gutierrez Perez, M.; Sabater Martin, S.

    2011-07-01

    The objective of this study was to compare the dosimetric distribution of gynecological brachytherapy treatment with high dose rate Ir-192 source as does a conventional planner versus dosimetric distribution obtained by Monte Carlo simulation taking into account (addition to the geometry of the source), gynecologic vaginal applicator (tube and vaginal cylinder or dome) and the anatomy of the patient. In particular we assessed the effect of the presence of iodinated contrast in the bladder of the patient.

  13. The evolution of computerized treatment planning for brachytherapy: American contributions.

    Science.gov (United States)

    Aronowitz, Jesse N; Rivard, Mark J

    2014-06-01

    To outline the evolution of computerized brachytherapy treatment planning in the United States through a review of technological developments and clinical practice refinements. A literature review was performed and interviews were conducted with six participants in the development of computerized treatment planning for brachytherapy. Computerized brachytherapy treatment planning software was initially developed in the Physics Departments of New York's Memorial Hospital (by Nelson, Meurk and Balter), and Houston's M. D. Anderson Hospital (by Stovall and Shalek). These public-domain programs could be used by institutions with adequate computational resources; other clinics had access to them via Memorial's and Anderson's teletype-based computational services. Commercial brachytherapy treatment planning programs designed to run on smaller computers (Prowess, ROCS, MMS), were developed in the late 1980s and early 1990s. These systems brought interactive dosimetry into the clinic and surgical theatre. Brachytherapy treatment planning has evolved from systems of rigid implant rules to individualized pre- and intra-operative treatment plans, and post-operative dosimetric assessments. Brachytherapy dose distributions were initially calculated on public domain programs on large regionally located computers. With the progression of computer miniaturization and increase in processor speeds, proprietary software was commercially developed for microcomputers that offered increased functionality and integration with clinical practice.

  14. Photon penetration depth in human brain for light stimulation and treatment: A realistic Monte Carlo simulation study

    Directory of Open Access Journals (Sweden)

    Ting Li

    2017-09-01

    Full Text Available Light has been clinically utilized as a stimulation in medical treatment, such as Low-level laser therapy and photodynamic therapy, which has been more and more widely accepted in public. The penetration depth of the treatment light is important for precision treatment and safety control. The issue of light penetration has been highlighted in biomedical optics field for decades. However, quantitative research is sparse and even there are conflicts of view on the capability of near-infrared light penetration into brain tissue. This study attempts to quantitatively revisit this issue by innovative high-realistic 3D Monte Carlo modeling of stimulated light penetration within high-precision Visible Chinese human head. The properties of light, such as its wavelength, illumination profile and size are concern in this study. We made straightforward and quantitative comparisons among the effects by the light properties (i.e., wavelengths: 660, 810 and 980nm; beam types: Gaussian and flat beam; beam diameters: 0, 2, 4 and 6cm which are in the range of light treatment. The findings include about 3% of light dosage within brain tissue; the combination of Gaussian beam and 810nm light make the maximum light penetration (>5cm, which allows light to cross through gray matter into white mater. This study offered us, the first time as we know, quantitative guide for light stimulation parameter optimization in medical treatment.

  15. Image registration: An essential part of radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Rosenman, Julian G.; Miller, Elizabeth P.; Tracton, Gregg; Cullip, Tim J.

    1998-01-01

    Purpose: We believe that a three-dimensional (3D) registration of nonplanning (diagnostic) imaging data with the planning computed tomography (CT) offers a substantial improvement in tumor target identification for many radiation therapy patients. The purpose of this article is to review and discuss our experience to date. Methods and Materials: We reviewed the charts and treatment planning records of all patients that underwent 3D radiation treatment planning in our department from June 1994 to December 1995, to learn which patients had image registration performed and why it was thought they would benefit from this approach. We also measured how much error would have been introduced into the target definition if the nonplanning imaging data had not been available and only the planning CT had been used. Results: Between June 1994 and December 1995, 106 of 246 (43%) of patients undergoing 3D treatment planning had image registration. Four reasons for performing registration were identified. First, some tumor volumes have better definition on magnetic resonance imaging (MRI) than on CT. Second, a properly contrasted diagnostic CT sometimes can show the tumor target better than can the planning CT. Third, the diagnostic CT or MR may have been preoperative, with the postoperative planning CT no longer showing the tumor. Fourth, the patient may have undergone cytoreductive chemotherapy so that the postchemotherapy planning CT no longer showed the original tumor volume. In patients in whom the planning CT did not show the tumor volume well an analysis was done to determine how the treatment plan was changed with the addition of a better tumor-defining nonplanning CT or MR. We have found that the use of this additional imaging modality changed the tumor location in the treatment plan at least 1.5 cm for half of the patients, and up to 3.0 cm for ((1)/(4)) of the patients. Conclusions: Multimodality and/or sequential imaging can substantially aid in better tumor

  16. 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

  17. Modulated electron radiotherapy treatment planning using a photon multileaf collimator for post-mastectomized chest walls

    International Nuclear Information System (INIS)

    Salguero, Francisco Javier; Palma, Bianey; Arrans, Rafael; Rosello, Joan; Leal, Antonio

    2009-01-01

    Background and purpose: To evaluate the feasibility of using a photon MLC (xMLC) for modulated electron radiotherapy treatment (MERT) as an alternative to conventional post-mastectomy chest wall (CW) irradiation. A Monte Carlo (MC) based planning system was developed to overcome the inaccuracy of the 'pencil beam' algorithm. MC techniques are known to accurately calculate the dose distributions of electron beams, allowing the explicit simulation of electron interactions within the MLC. Materials and methods: Four real clinical CW cases were planned using MERT which were compared with the conventional electron treatments based on blocks and by a straightforward approach using the MLC, and not the blocks (as an intermediate step to MERT) to shape the same segments with SSD between 60 and 70 cm depending on PTV size. MC calculations were verified with an array of ionization chambers and radiochromic films in a solid water phantom. Results: Tests based on gamma analysis between MC dose distributions and radiochromic film measurements showed an excellent agreement. Differences in the absolute dose measured with a plane-parallel chamber at a reference point were below 3% for all cases. MERT solution showed a better PTV coverage and a significant reduction of the doses to the organs at risk (OARs). Conclusion: MERT can effectively improve the current electron treatments by obtaining a better PTV coverage and sparing healthy tissues. More directly, block-shaped treatments could be replaced by MLC-shaped non-modulated segments providing similar results.

  18. 300 Area waste acid treatment system closure plan

    Energy Technology Data Exchange (ETDEWEB)

    LUKE, S.N.

    1999-05-17

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999.

  19. 300 Area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    LUKE, S.N.

    1999-01-01

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999

  20. SBNCT plan: A 3-dimensional treatment planning system for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Reinstein, L.E.; Ramsay, E.B.; Gajewski, J.; Ramamoorthy, S.; Meek, A.G.

    1993-01-01

    The need for accurate and comprehensive 3-dimensional treatment planning for boron neutron capture therapy (BNCT) has been debated for the past several years. Although many argue against the need for elaborate and expensive treatment planning programs which mimic conventional radiotherapy planning systems, it is clear that in order to realize significant gains over conventional fractionated radiation therapy, patients must be treated to the edge of normal tissue tolerance. Just how close to this edge is dictated by the uncertainties in dosimetry. Hence the focus of BNCT planning is the determination of dose distribution throughout normal tissue volumes. Although precise geometric manipulation of the epithermal neutron beam is not achievable, the following variables play an important role in BNCT optimization: patient orientation, dose fractionation, number of fields, megawatt-minutes per fraction, use of surface bolus, and use of collimation. Other variables which are not as easily adjustable and would not, therefore, be part of treatment planning optimization, include external patient contour, internal patient heterogeneities, boron compound distributions, and RBE's. The boron neutron capture therapy planning system developed at SUNY Stony Brook (SBNCT-Plan) was designed as an interactive graphic tool to assist the radiation oncologist in generating the optimum plan for a neutron capture treatment

  1. Monte Carlo modelling of photodynamic therapy treatments comparing clustered three dimensional tumour structures with homogeneous tissue structures

    Science.gov (United States)

    Campbell, C. L.; Wood, K.; Brown, C. T. A.; Moseley, H.

    2016-07-01

    We explore the effects of three dimensional (3D) tumour structures on depth dependent fluence rates, photodynamic doses (PDD) and fluorescence images through Monte Carlo radiation transfer modelling of photodynamic therapy. The aim with this work was to compare the commonly used uniform tumour densities with non-uniform densities to determine the importance of including 3D models in theoretical investigations. It was found that fractal 3D models resulted in deeper penetration on average of therapeutic radiation and higher PDD. An increase in effective treatment depth of 1 mm was observed for one of the investigated fractal structures, when comparing to the equivalent smooth model. Wide field fluorescence images were simulated, revealing information about the relationship between tumour structure and the appearance of the fluorescence intensity. Our models indicate that the 3D tumour structure strongly affects the spatial distribution of therapeutic light, the PDD and the wide field appearance of surface fluorescence images.

  2. Sodium-Bearing Waste Treatment, Applied Technology Plan

    Energy Technology Data Exchange (ETDEWEB)

    Lance Lauerhass; Vince C. Maio; S. Kenneth Merrill; Arlin L. Olson; Keith J. Perry

    2003-06-01

    Settlement Agreement between the Department of Energy and the State of Idaho mandates treatment of sodium-bearing waste at the Idaho Nuclear Technology and Engineering Center within the Idaho National Engineering and Environmental Laboratory. One of the requirements of the Settlement Agreement is to complete treatment of sodium-bearing waste by December 31, 2012. Applied technology activities are required to provide the data necessary to complete conceptual design of four identified alternative processes and to select the preferred alternative. To provide a technically defensible path forward for the selection of a treatment process and for the collection of needed data, an applied technology plan is required. This document presents that plan, identifying key elements of the decision process and the steps necessary to obtain the required data in support of both the decision and the conceptual design. The Sodium-Bearing Waste Treatment Applied Technology Plan has been prepared to provide a description/roadmap of the treatment alternative selection process. The plan details the results of risk analyzes and the resulting prioritized uncertainties. It presents a high-level flow diagram governing the technology decision process, as well as detailed roadmaps for each technology. The roadmaps describe the technical steps necessary in obtaining data to quantify and reduce the technical uncertainties associated with each alternative treatment process. This plan also describes the final products that will be delivered to the Department of Energy Idaho Operations Office in support of the office's selection of the final treatment technology.

  3. Using Monte Carlo modelling in optimising treatment outcome in advanced head and neck cancers treated with chemoradiotherapy

    International Nuclear Information System (INIS)

    Marcu, L.G.; Bezak, E.

    2011-01-01

    Full text: Advanced head and neck cancers are highly aggressive therefore they require corresponding treatment. Alterations in radiotherapy fractionation are possible ways to improve tumour control. However, while radiotherapy alone has an impact on the short term prognosis, long-term benefits are only moderate. Chemotherapy, whether concurrent or neoadjuvant, offers a possible way to improve treatment outcome. A Monte Carlo model was developed to demonstrate the role of cisplatin in altered fractionation radiotherapy and to develop a less customary schedule for neoadjuvant chemotherapy. Cisplatin combined with conventional radiotherapy was shown to improve patient survival. A Monte Carlo model was developed to assess the effect of combined cisplatin-altered fractionation schedule on a virtual head and neck tumour. Radiotherapy was simulated using the linear-quadratic formalism, whereas the cisplatin model was based on experimental data. Various neoadjuvant schedules were designed for cisplatin to optimize therapeutic ratio without increasing normal tissue toxicity. Concurrent daily cisplatin + altered fractionated radiotherapy have a notable effect on repopulation: while a TCP of 97.9% is reached with 60 Gy accelerated radiotherapy, the same TCP is achieved with daily cisplatin + 26 Gy accelerated radiotherapy (43% of the dose). Neoadjuvant cisplatin administered every third day leads to the same cell kill as daily cisplatin but with lower tissue toxicity. Conclusions Cisplatin both concurrently and prior to radiation offer superior tumour control as compared to radiation alone. Whilst the model outcome is valid for a small tumour (5 x 106 cells) the results can be extrapolated to obtain equivalent data for a clinically detectable tumour.

  4. A comparison between anisotropic analytical and multigrid superposition dose calculation algorithms in radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Vincent W.C., E-mail: htvinwu@polyu.edu.hk [Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (Hong Kong); Tse, Teddy K.H.; Ho, Cola L.M.; Yeung, Eric C.Y. [Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR (Hong Kong)

    2013-07-01

    Monte Carlo (MC) simulation is currently the most accurate dose calculation algorithm in radiotherapy planning but requires relatively long processing time. Faster model-based algorithms such as the anisotropic analytical algorithm (AAA) by the Eclipse treatment planning system and multigrid superposition (MGS) by the XiO treatment planning system are 2 commonly used algorithms. This study compared AAA and MGS against MC, as the gold standard, on brain, nasopharynx, lung, and prostate cancer patients. Computed tomography of 6 patients of each cancer type was used. The same hypothetical treatment plan using the same machine and treatment prescription was computed for each case by each planning system using their respective dose calculation algorithm. The doses at reference points including (1) soft tissues only, (2) bones only, (3) air cavities only, (4) soft tissue-bone boundary (Soft/Bone), (5) soft tissue-air boundary (Soft/Air), and (6) bone-air boundary (Bone/Air), were measured and compared using the mean absolute percentage error (MAPE), which was a function of the percentage dose deviations from MC. Besides, the computation time of each treatment plan was recorded and compared. The MAPEs of MGS were significantly lower than AAA in all types of cancers (p<0.001). With regards to body density combinations, the MAPE of AAA ranged from 1.8% (soft tissue) to 4.9% (Bone/Air), whereas that of MGS from 1.6% (air cavities) to 2.9% (Soft/Bone). The MAPEs of MGS (2.6%±2.1) were significantly lower than that of AAA (3.7%±2.5) in all tissue density combinations (p<0.001). The mean computation time of AAA for all treatment plans was significantly lower than that of the MGS (p<0.001). Both AAA and MGS algorithms demonstrated dose deviations of less than 4.0% in most clinical cases and their performance was better in homogeneous tissues than at tissue boundaries. In general, MGS demonstrated relatively smaller dose deviations than AAA but required longer computation time.

  5. A comparison between anisotropic analytical and multigrid superposition dose calculation algorithms in radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Wu, Vincent W.C.; Tse, Teddy K.H.; Ho, Cola L.M.; Yeung, Eric C.Y.

    2013-01-01

    Monte Carlo (MC) simulation is currently the most accurate dose calculation algorithm in radiotherapy planning but requires relatively long processing time. Faster model-based algorithms such as the anisotropic analytical algorithm (AAA) by the Eclipse treatment planning system and multigrid superposition (MGS) by the XiO treatment planning system are 2 commonly used algorithms. This study compared AAA and MGS against MC, as the gold standard, on brain, nasopharynx, lung, and prostate cancer patients. Computed tomography of 6 patients of each cancer type was used. The same hypothetical treatment plan using the same machine and treatment prescription was computed for each case by each planning system using their respective dose calculation algorithm. The doses at reference points including (1) soft tissues only, (2) bones only, (3) air cavities only, (4) soft tissue-bone boundary (Soft/Bone), (5) soft tissue-air boundary (Soft/Air), and (6) bone-air boundary (Bone/Air), were measured and compared using the mean absolute percentage error (MAPE), which was a function of the percentage dose deviations from MC. Besides, the computation time of each treatment plan was recorded and compared. The MAPEs of MGS were significantly lower than AAA in all types of cancers (p<0.001). With regards to body density combinations, the MAPE of AAA ranged from 1.8% (soft tissue) to 4.9% (Bone/Air), whereas that of MGS from 1.6% (air cavities) to 2.9% (Soft/Bone). The MAPEs of MGS (2.6%±2.1) were significantly lower than that of AAA (3.7%±2.5) in all tissue density combinations (p<0.001). The mean computation time of AAA for all treatment plans was significantly lower than that of the MGS (p<0.001). Both AAA and MGS algorithms demonstrated dose deviations of less than 4.0% in most clinical cases and their performance was better in homogeneous tissues than at tissue boundaries. In general, MGS demonstrated relatively smaller dose deviations than AAA but required longer computation time

  6. SU-F-T-564: 3 Year Experience of Treatment Plan QualityAssurance for Vero SBRT Patients

    Energy Technology Data Exchange (ETDEWEB)

    Su, Z; Li, Z [University of Florida, Jacksonville, FL (United States); Mamalui, M [University of Florida/Radiation Oncology, Jacksonville, FL (United States)

    2016-06-15

    Purpose: To verify treatment plan monitor units from iPlan treatment planning system for Vero Stereotactic Body Radiotherapy (SBRT) treatment using both software-based and (homogeneous and heterogeneous) phantom-based approaches. Methods: Dynamic conformal arcs (DCA) were used for SBRT treatment of oligometastasis patients using Vero linear accelerator. For each plan, Monte Carlo calculated treatment plans MU (prescribed dose to water with 1% variance) is verified first by RadCalc software with 3% difference threshold. Beyond 3% differences, treatment plans were copied onto (homogeneous) Scanditronix phantom for non-lung patients and copied onto (heterogeneous) CIRS phantom for lung patients and the corresponding plan dose was measured using a cc01 ion chamber. The difference between the planed and measured dose was recorded. For the past 3 years, we have treated 180 patients with 315 targets. Out of these patients, 99 targets treatment plan RadCalc calculation exceeded 3% threshold and phantom based measurements were performed with 26 plans using Scanditronix phantom and 73 plans using CIRS phantom. Mean and standard deviation of the dose differences were obtained and presented. Results: For all patient RadCalc calculations, the mean dose difference is 0.76% with a standard deviation of 5.97%. For non-lung patient plan Scanditronix phantom measurements, the mean dose difference is 0.54% with standard deviation of 2.53%; for lung patient plan CIRS phantom measurements, the mean dose difference is −0.04% with a standard deviation of 1.09%; The maximum dose difference is 3.47% for Scanditronix phantom measurements and 3.08% for CIRS phantom measurements. Conclusion: Limitations in secondary MU check software lead to perceived large dose discrepancies for some of the lung patient SBRT treatment plans. Homogeneous and heterogeneous phantoms were used in plan quality assurance for non-lung patients and lung patients, respectively. Phantom based QA showed the relative

  7. SU-F-T-564: 3 Year Experience of Treatment Plan QualityAssurance for Vero SBRT Patients

    International Nuclear Information System (INIS)

    Su, Z; Li, Z; Mamalui, M

    2016-01-01

    Purpose: To verify treatment plan monitor units from iPlan treatment planning system for Vero Stereotactic Body Radiotherapy (SBRT) treatment using both software-based and (homogeneous and heterogeneous) phantom-based approaches. Methods: Dynamic conformal arcs (DCA) were used for SBRT treatment of oligometastasis patients using Vero linear accelerator. For each plan, Monte Carlo calculated treatment plans MU (prescribed dose to water with 1% variance) is verified first by RadCalc software with 3% difference threshold. Beyond 3% differences, treatment plans were copied onto (homogeneous) Scanditronix phantom for non-lung patients and copied onto (heterogeneous) CIRS phantom for lung patients and the corresponding plan dose was measured using a cc01 ion chamber. The difference between the planed and measured dose was recorded. For the past 3 years, we have treated 180 patients with 315 targets. Out of these patients, 99 targets treatment plan RadCalc calculation exceeded 3% threshold and phantom based measurements were performed with 26 plans using Scanditronix phantom and 73 plans using CIRS phantom. Mean and standard deviation of the dose differences were obtained and presented. Results: For all patient RadCalc calculations, the mean dose difference is 0.76% with a standard deviation of 5.97%. For non-lung patient plan Scanditronix phantom measurements, the mean dose difference is 0.54% with standard deviation of 2.53%; for lung patient plan CIRS phantom measurements, the mean dose difference is −0.04% with a standard deviation of 1.09%; The maximum dose difference is 3.47% for Scanditronix phantom measurements and 3.08% for CIRS phantom measurements. Conclusion: Limitations in secondary MU check software lead to perceived large dose discrepancies for some of the lung patient SBRT treatment plans. Homogeneous and heterogeneous phantoms were used in plan quality assurance for non-lung patients and lung patients, respectively. Phantom based QA showed the relative

  8. A comparison of Monte Carlo and Fermi-Eyges-Hogstrom estimates of heart and lung dose from breast electron boost treatment

    International Nuclear Information System (INIS)

    Coleman, Joy; Park, Catherine; Villarreal-Barajas, J. Eduardo; Petti, Paula; Faddegon, Bruce

    2005-01-01

    Purpose: Electrons are commonly used in the treatment of breast cancer primarily to deliver a tumor bed boost. We compared the use of the Monte Carlo (MC) method and the Fermi-Eyges-Hogstrom (FEH) algorithm to calculate the dose distribution of electron treatment to normal tissues. Methods and materials: Ten patients with left-sided breast cancer treated with breast-conservation therapy at the University of California, San Francisco, were included in this study. Each patient received an electron boost to the surgical bed to a dose of 1,600 cGy in 200 cGy fractions prescribed to 80% of the maximum. Doses to the left ventricle (LV) and the ipsilateral lung (IL) were calculated using the EGS4 MC system and the FEH algorithm implemented on the commercially available Pinnacle treatment planning system. An anthromorphic phantom was irradiated with radiochromic film in place to verify the accuracy of the MC system. Results: Dose distributions calculated with the MC algorithm agreed with the film measurements within 3% or 3 mm. For all patients in the study, the dose to the LV and IL was relatively low as calculated by MC. That is, the maximum dose received by up to 98% of the LV volume was 30 cGy and differences in maximum dose of < 35 cGy/day to the LV and 80 cGy/day to the IL. Conclusions: From our series, using clinical judgment to prescribe the boost to the surgical bed after breast-conserving treatment results in low doses to the underlying LV and IL. When calculated dose distributions are desired, MC is the most accurate, but FEH can still be used

  9. A Study of Treatment Planning: Periodontal Services for the Elderly.

    Science.gov (United States)

    Milgrom, Peter; And Others

    1981-01-01

    A study undertaken to explore how dentists use patient data to plan treatment is presented. Three hundred forty-six general dentists used oral and general health findings to determine periodontal treatment for seven prototypic elderly patients. The results indicated that oral hygiene and major medications best discriminated between treatment…

  10. Uncertainty incorporated beam angle optimization for IMPT treatment planning.

    Science.gov (United States)

    Cao, Wenhua; Lim, Gino J; Lee, Andrew; Li, Yupeng; Liu, Wei; Ronald Zhu, X; Zhang, Xiaodong

    2012-08-01

    Beam angle optimization (BAO) by far remains an important and challenging problem in external beam radiation therapy treatment planning. Conventional BAO algorithms discussed in previous studies all focused on photon-based therapies. Impact of BAO on proton therapy is important while proton therapy increasingly receives great interests. This study focuses on potential benefits of BAO on intensity-modulated proton therapy (IMPT) that recently began available to clinical cancer treatment. The authors have developed a novel uncertainty incorporated BAO algorithm for IMPT treatment planning in that IMPT plan quality is highly sensitive to uncertainties such as proton range and setup errors. A linear programming was used to optimize robust intensity maps to scenario-based uncertainties for an incident beam angle configuration. Unlike conventional intensity-modulated radiation therapy with photons (IMXT), the search space for IMPT treatment beam angles may be relatively small but optimizing an IMPT plan may require higher computational costs due to larger data size. Therefore, a deterministic local neighborhood search algorithm that only needs a very limited number of plan objective evaluations was used to optimize beam angles in IMPT treatment planning. Three prostate cancer cases and two skull base chordoma cases were studied to demonstrate the dosimetric advantages and robustness of optimized beam angles from the proposed BAO algorithm. Two- to four-beam plans were optimized for prostate cases, and two- and three-beam plans were optimized for skull base cases. By comparing plans with conventional two parallel-opposed angles, all plans with optimized angles consistently improved sparing at organs at risks, i.e., rectum and femoral heads for prostate, brainstem for skull base, in either nominal dose distribution or uncertainty-based dose distributions. The efficiency of the BAO algorithm was demonstrated by comparing it with alternative methods including simulated

  11. Periodontal risk assessment, diagnosis and treatment planning.

    Science.gov (United States)

    Pihlstrom, B L

    2001-01-01

    The prevention and treatment of the periodontal diseases is based on accurate diagnosis, reduction or elimination of causative agents, risk management and correction of the harmful effects of disease. Prominent and confirmed risk factors or risk predictors for periodontitis in adults include smoking, diabetes, race, P. gingivalis, P. intermedia, low education, infrequent dental attendance and genetic influences. Several other specific periodontal bacteria, herpesviruses, increased age, male, sex, depression, race, traumatic occlusion and female osteoporosis in the presence of heavy dental calculus have been shown to be associated with loss of periodontal support and can be considered to be risk indicators of periodontitis. The presence of furcation involvement, tooth mobility, and a parafunctional habit without the use of a biteguard are associated with a poorer periodontal prognosis following periodontal therapy. An accurate diagnosis can only be made by a thorough evaluation of data that have been systematically collected by: 1) patient interview, 2) medical consultation as indicated, 3) clinical periodontal examination, 4) radiographic examination, and 5) laboratory tests as needed. Clinical signs of periodontal disease such as pocket depth, loss of clinical attachment and bone loss are cumulative measures of past disease. They do not provide the dentist with a current assessment of disease activity. In an attempt to improve the ability to predict future disease progression, several types of diagnostic tests have been studied, including host inflammatory products and mediators, enzymes, tissue breakdown products and subgingival temperature. In general, the usefulness of these tests for predicting future disease activity remains to be established in terms of sensitivity, specificity and predictive value. Although microbiological analysis of subgingival plaque is not necessary to diagnose and treat most patients with periodontitis, it is helpful when treating

  12. A study of planning dose constraints for treatment of nasopharyngeal carcinoma using a commercial inverse treatment planning system.

    Science.gov (United States)

    Xia, Ping; Lee, Nancy; Liu, Yu-Ming; Poon, Ian; Weinberg, Vivian; Shin, Edward; Quivey, Jeanne M; Verhey, Lynn J

    2004-07-01

    The purpose of this study was to develop and test planning dose constraint templates for tumor and normal structures in the treatment of nasopharyngeal carcinoma (NPC) using a specific commercial inverse treatment planning system. Planning dose constraint templates were developed based on the analyses of dose-volume histograms (DVHs) of tumor targets and adjacent sensitive structures by clinically approved treatment plans of 9 T1-2 and 16 T3-4 NPC patients treated with inverse planned intensity-modulated radiation therapy (IP-IMRT). DVHs of sensitive structures were analyzed by examining multiple defined endpoints, based on the characteristics of each sensitive structure. For each subgroup of patients with T1-2 and T3-4 NPC, the resulting mean values of these defined endpoint doses were considered as templates for planning dose constraints and subsequently applied to a second group of patients, 5 with T1-2 NPC and 5 with T3-4 NPC. The 10 regenerated plans (called new plans) were compared to the original clinical plans that were used to treat the second group of patients, based on plan conformity index and DVHs. The conformity indices of the new plans were comparable to the original plans with no statistical difference (p = 0.85). Among the serial sensitive structures evaluated, there was a significant decrease with the new plans in the dose to the spinal cord when analyzed by the maximum dose (p = 0.001), doses encompassing 1 cc of the spinal cord volume (p = 0.001) and 3 cc of the spinal cord volume (p = 0.001). There was no significant difference in the mean maximum dose to the brainstem between the new plans and the original plans (p = 0.36). However, a significant difference in the mean maximum dose to the brainstem was seen among the different T-stages (p = 0.04). A decrease with the new plan to the brainstem in the doses encompassing 5% and 10% of the volume was of borderline statistical significance (p = 0.08 and p = 0.06, respectively). There were no

  13. Solid Mesh Registration for Radiotherapy Treatment Planning

    DEFF Research Database (Denmark)

    Noe, Karsten Østergaard; Sørensen, Thomas Sangild

    2010-01-01

    We present an algorithm for solid organ registration of pre-segmented data represented as tetrahedral meshes. Registration of the organ surface is driven by force terms based on a distance field representation of the source and reference shapes. Registration of internal morphology is achieved using...... on phantom data and prostate data obtained in vivo based on fiducial marker accuracy and inverse consistency of transformations. The parallel nature of the method allows an efficient implementation on a GPU and as a result the method is very fast. All validation registrations take less than 30 seconds...... to complete. The proposed method has many potential uses in image guided radiotherapy (IGRT) which relies on registration to account for organ deformation between treatment sessions....

  14. Radiotherapy treatment planning using three dimensional CT images

    International Nuclear Information System (INIS)

    Araki, Yutaka; Isobe, Yoshihide; Ozaki, Shin; Hosoki, Takuya; Mori, Shigeru; Ikeda, Hiroshi.

    1984-01-01

    Recently superimposition of dose distribution onto CT images has become available with the use of planning computers. However, the distribution is mostly along the plane of central axis of the beam, and evaluation of the quality of planning has not been established yet. It cannot be concluded whether the planning is suitable or not, even if the dose distribution at a certain CT slice seems to be optimum. The need has been emerged to compare the treatment planning quantitatively with other ones. A computerized treatment planning system has been developed in our hospital, which can accumulate voxel dose of each lattice point, can superimpose isodose curves on multiple transverse contours, and can construct and display a 3-dimensional image of the treatment region using a ''cutting method''. In this paper, a method is proposed to evaluate the quality of treatment planning, introducing the definitions in ICRU report 29 and using the 3-dimensional computer algorism. Concepts and procedures are described in detail with some case examples. (author)

  15. Dose optimization based on linear programming implemented in a system for treatment planning in Monte Carlo

    International Nuclear Information System (INIS)

    Ureba, A.; Palma, B. A.; Leal, A.

    2011-01-01

    Develop a more efficient method of optimization in relation to time, based on linear programming designed to implement a multi objective penalty function which also permits a simultaneous solution integrated boost situations considering two white volumes simultaneously.

  16. Proton energy and scattering angle radiographs to improve proton treatment planning : a Monte Carlo study

    NARCIS (Netherlands)

    Biegun, Aleksandra; Takatsu, Jun; Nakaji, Taku; van Goethem, Marc-Jan; van der Graaf, Emiel; Koffeman, E.; Visser, Jan; Brandenburg, Sijtze

    2016-01-01

    The novel proton radiography imaging technique has a large potential to be used in direct measurement of the proton energy loss (proton stopping power, PSP) in various tissues in the patient. The uncertainty of PSPs, currently obtained from translation of X-ray Computed Tomography (xCT) images,

  17. Clinical implementation of full Monte Carlo dose calculation in proton beam therapy

    International Nuclear Information System (INIS)

    Paganetti, Harald; Jiang, Hongyu; Parodi, Katia; Slopsema, Roelf; Engelsman, Martijn

    2008-01-01

    The goal of this work was to facilitate the clinical use of Monte Carlo proton dose calculation to support routine treatment planning and delivery. The Monte Carlo code Geant4 was used to simulate the treatment head setup, including a time-dependent simulation of modulator wheels (for broad beam modulation) and magnetic field settings (for beam scanning). Any patient-field-specific setup can be modeled according to the treatment control system of the facility. The code was benchmarked against phantom measurements. Using a simulation of the ionization chamber reading in the treatment head allows the Monte Carlo dose to be specified in absolute units (Gy per ionization chamber reading). Next, the capability of reading CT data information was implemented into the Monte Carlo code to model patient anatomy. To allow time-efficient dose calculation, the standard Geant4 tracking algorithm was modified. Finally, a software link of the Monte Carlo dose engine to the patient database and the commercial planning system was established to allow data exchange, thus completing the implementation of the proton Monte Carlo dose calculation engine ('DoC++'). Monte Carlo re-calculated plans are a valuable tool to revisit decisions in the planning process. Identification of clinically significant differences between Monte Carlo and pencil-beam-based dose calculations may also drive improvements of current pencil-beam methods. As an example, four patients (29 fields in total) with tumors in the head and neck regions were analyzed. Differences between the pencil-beam algorithm and Monte Carlo were identified in particular near the end of range, both due to dose degradation and overall differences in range prediction due to bony anatomy in the beam path. Further, the Monte Carlo reports dose-to-tissue as compared to dose-to-water by the planning system. Our implementation is tailored to a specific Monte Carlo code and the treatment planning system XiO (Computerized Medical Systems Inc

  18. Monte carlo dose calculation in dental amalgam phantom

    OpenAIRE

    Mohd Zahri Abdul Aziz; A L Yusoff; N D Osman; R Abdullah; N A Rabaie; M S Salikin

    2015-01-01

    It has become a great challenge in the modern radiation treatment to ensure the accuracy of treatment delivery in electron beam therapy. Tissue inhomogeneity has become one of the factors for accurate dose calculation, and this requires complex algorithm calculation like Monte Carlo (MC). On the other hand, computed tomography (CT) images used in treatment planning system need to be trustful as they are the input in radiotherapy treatment. However, with the presence of metal amalgam in treatm...

  19. SU-F-T-373: Monte Carlo Versus Pencil Beam Dose Calculation for Spine SBRT Treatments Using HybridARC and Sliding Windows IMRT

    International Nuclear Information System (INIS)

    Venencia, C; Pino, M; Caussa, L; Garrigo, E; Molineu, A

    2016-01-01

    Purpose: The purpose of this work was to quantify the dosimetric impact of Monte Carlo (MC) dose calculation algorithm compared to Pencil Beam (PB) on Spine SBRT with HybridARC (HA) and sliding windows IMRT (dMLC) treatment modality. Methods: A 6MV beam (1000MU/min) produced by a Novalis TX (BrainLAB-Varian) equipped with HDMLC was used. HA uses 1 arc plus 8 IMRT beams (arc weight between 60–40%) and dIMRT 15 beams. Plans were calculated using iPlan v.4.5.3 (BrainLAB) and the treatment dose prescription was 27Gy in 3 fractions. Dose calculation was done by PB (4mm spatial resolution) with heterogeneity correction and MC dose to water (4mm spatial resolution and 4% mean variance). PTV and spinal cord dose comparison were done. Study was done on 12 patients. IROC Spine Phantom was used to validate HA and quantify dose variation using PB and MC algorithm. Results: The difference between PB and MC for PTV D98%, D95%, Dmean, D2% were 2.6% [−5.1, 6.8], 0.1% [−4.2, 5.4], 0.9% [−1.5, 3.8] and 2.4% [−0.5, 8.3]. The difference between PB and MC for spinal cord Dmax, D1.2cc and D0.35cc were 5.3% [−6.4, 18.4], 9% [−7.0, 17.0] and 7.6% [−0.6, 14.8] respectively. IROC spine phantom shows PTV TLD dose variation of 0.98% for PB and 1.01% for MC. Axial and sagittal film plane gamma index (5%-3mm) was 95% and 97% for PB and 95% and 99% for MC. Conclusion: PB slightly underestimates the dose for the PTV. For the spinal cord PB underestimates the dose and dose differences could be as high as 18% which could have unexpected clinical impact. CI shows no variation between PB and MC for both treatment modalities Treatment modalities have no impact with the dose calculation algorithms used. Following the IROC pass-fail criteria, treatment acceptance requirement was fulfilled for PB and MC.

  20. SU-D-BRD-03: Improving Plan Quality with Automation of Treatment Plan Checks

    Energy Technology Data Exchange (ETDEWEB)

    Covington, E; Younge, K; Chen, X; Lee, C; Matuszak, M; Kessler, M; Acosta, E; Orow, A; Filpansick, S; Moran, J [University of Michigan Hospital and Health System, Ann Arbor, MI (United States); Keranen, W [Varian Medical Systems, Palo Alto, CA (United States)

    2015-06-15

    Purpose: To evaluate the effectiveness of an automated plan check tool to improve first-time plan quality as well as standardize and document performance of physics plan checks. Methods: The Plan Checker Tool (PCT) uses the Eclipse Scripting API to check and compare data from the treatment planning system (TPS) and treatment management system (TMS). PCT was created to improve first-time plan quality, reduce patient delays, increase efficiency of our electronic workflow, and to standardize and partially automate plan checks in the TPS. A framework was developed which can be configured with different reference values and types of checks. One example is the prescribed dose check where PCT flags the user when the planned dose and the prescribed dose disagree. PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user. A PDF report is created and automatically uploaded into the TMS. Prior to and during PCT development, errors caught during plan checks and also patient delays were tracked in order to prioritize which checks should be automated. The most common and significant errors were determined. Results: Nineteen of 33 checklist items were automated with data extracted with the PCT. These include checks for prescription, reference point and machine scheduling errors which are three of the top six causes of patient delays related to physics and dosimetry. Since the clinical roll-out, no delays have been due to errors that are automatically flagged by the PCT. Development continues to automate the remaining checks. Conclusion: With PCT, 57% of the physics plan checklist has been partially or fully automated. Treatment delays have declined since release of the PCT for clinical use. By tracking delays and errors, we have been able to measure the effectiveness of automating checks and are using this information to prioritize future development. This project was supported in part by P01CA059827.

  1. SU-D-BRD-03: Improving Plan Quality with Automation of Treatment Plan Checks

    International Nuclear Information System (INIS)

    Covington, E; Younge, K; Chen, X; Lee, C; Matuszak, M; Kessler, M; Acosta, E; Orow, A; Filpansick, S; Moran, J; Keranen, W

    2015-01-01

    Purpose: To evaluate the effectiveness of an automated plan check tool to improve first-time plan quality as well as standardize and document performance of physics plan checks. Methods: The Plan Checker Tool (PCT) uses the Eclipse Scripting API to check and compare data from the treatment planning system (TPS) and treatment management system (TMS). PCT was created to improve first-time plan quality, reduce patient delays, increase efficiency of our electronic workflow, and to standardize and partially automate plan checks in the TPS. A framework was developed which can be configured with different reference values and types of checks. One example is the prescribed dose check where PCT flags the user when the planned dose and the prescribed dose disagree. PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user. A PDF report is created and automatically uploaded into the TMS. Prior to and during PCT development, errors caught during plan checks and also patient delays were tracked in order to prioritize which checks should be automated. The most common and significant errors were determined. Results: Nineteen of 33 checklist items were automated with data extracted with the PCT. These include checks for prescription, reference point and machine scheduling errors which are three of the top six causes of patient delays related to physics and dosimetry. Since the clinical roll-out, no delays have been due to errors that are automatically flagged by the PCT. Development continues to automate the remaining checks. Conclusion: With PCT, 57% of the physics plan checklist has been partially or fully automated. Treatment delays have declined since release of the PCT for clinical use. By tracking delays and errors, we have been able to measure the effectiveness of automating checks and are using this information to prioritize future development. This project was supported in part by P01CA059827

  2. Prostate HDR brachytherapy catheter displacement between planning and treatment delivery

    International Nuclear Information System (INIS)

    Whitaker, May; Hruby, George; Lovett, Aimee; Patanjali, Nitya

    2011-01-01

    Background and purpose: HDR brachytherapy is used as a conformal boost for treating prostate cancer. Given the large doses delivered, it is critical that the volume treated matches that planned. Our outpatient protocol comprises two 9 Gy fractions, two weeks apart. We prospectively assessed catheter displacement between CT planning and treatment delivery. Materials and methods: Three fiducial markers and the catheters were implanted under transrectal ultrasound guidance. Metal marker wires were inserted into 4 reference catheters before CT; marker positions relative to each other and to the marker wires were measured from the CT scout. Measurements were repeated immediately prior to treatment delivery using pelvic X-ray with marker wires in the same reference catheters. Measurements from CT scout and film were compared. For displacements of 5 mm or more, indexer positions were adjusted prior to treatment delivery. Results: Results are based on 48 implants, in 25 patients. Median time from planning CT to treatment delivery was 254 min (range 81–367 min). Median catheter displacement was 7.5 mm (range −2.9–23.9 mm), 67% of implants had displacement of 5 mm or greater. Displacements were predominantly caudal. Conclusions: Catheter displacement can occur in the 1–3 h between the planning CT scan and treatment. It is recommended that departments performing HDR prostate brachytherapy verify catheter positions immediately prior to treatment delivery.

  3. SERA - an advanced treatment planning system for neutron therapy

    International Nuclear Information System (INIS)

    Wheeler, F.J.; Wessol, D.E.; Wemple, C.A.; Nigg, D.W.; Albright, C.L.; Cohen, M.T.; Frandsen, M.W.; Harkin, G.J.; Rossmeier, M.B.

    2001-01-01

    The technology for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT) has advanced significantly over the past few years. Because of the more complex nature of the problem, the computational methods that work well for treatment planning in photon radiotherapy are not applicable to BNCT. The necessary methods have, however, been developed and have been successfully employed both for research applications as well as human trials. Computational geometry for BNCT applications can be constructed directly from tomographic medical imagery and computed radiation dose distributions can be readily displayed in formats that are familiar to the radiotherapy community. The SERA system represents a significant advance in several areas for treatment planning. However further improvements in speed and results presentation are still needed for routine clinical applications, particularly when optimization of dose pattern is required. (author)

  4. SERA - An Advanced Treatment Planning System for Neutron Therapy

    International Nuclear Information System (INIS)

    Wemple, C. A.; Albright, C. L.; Nigg, D. W.; Wessol, D. W.; Wheeler, F. J.; Harkin, G. J.; Rossmeirer, M. B.; Cohen, M. T.; Frandsen, M. W.

    1999-01-01

    The technology for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT) has advanced significantly over the past few years. Because of the more complex nature of the problem, the computational methods that work well for treatment planning in photon radiotherapy are not applicable to BNCT. The necessary methods have, however, been developed and have been successfully employed both for research applications as well as human trials. Computational geometry for BNCT applications can be constructed directly from tomographic medical imagery and computed radiation dose distributions can be readily displayed in formats that are familiar to the radiotherapy community. The SERA system represents a significant advance in several areas for treatment planning. However further improvements in speed and results presentation are still needed for routine clinical applications, particularly when optimizations of dose pattern is required

  5. Application of DEC PRO-380 microcomputer for treatment planning. 129

    International Nuclear Information System (INIS)

    Chung-Bin, D.; Bernard, D.; Chung-Bin, A.

    1987-01-01

    Since 1974 we have used a PDP 11/45 computer manufactured by Digital Equipment Corp. for radiation therapy treatment planning. The Cunningham TAR method has been used for developing algorithms for external beam treatment planning. The Stovell and Shalek method has been used for intracavitary and interstitial implants. Recently we have implemented all this softwre on a DEC Pro 380 microcomputer with graphic input and output. This inexpensive machine has computer power comparable to that of a PDP 11/45. All the hardware is standard DEC equipment except the digitizer. This system is adequate to meet all the treatment planning needs of any moderate size radiation therapy center. It lacks the ability to input CT data directly from magnetic tape, but it can enter the contour, tumor volumes and inhomogeneity from a CT film using the back-lighted digitizer. 2 refs

  6. SERA - An Advanced Treatment Planning System for Neutron Therapy

    Energy Technology Data Exchange (ETDEWEB)

    C. A. Wemple; C. L. Albright; D. W. Nigg; D. W. Wessol; F. J. Wheeler; G. J. Harkin; M. B. Rossmeirer; M. T. Cohen; M. W. Frandsen

    1999-06-01

    The technology for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT) has advanced significantly over the past few years. Because of the more complex nature of the problem, the computational methods that work well for treatment planning in photon radiotherapy are not applicable to BNCT. The necessary methods have, however, been developed and have been successfully employed both for research applications as well as human trials. Computational geometry for BNCT applications can be constructed directly from tomographic medical imagery and computed radiation dose distributions can be readily displayed in formats that are familiar to the radiotherapy community. The SERA system represents a significant advance in several areas for treatment planning. However further improvements in speed and results presentation are still needed for routine clinical applications, particularly when optimizations of dose pattern is required.

  7. Orthognathic Surgery: Planning and treatment with illustration on six cases

    International Nuclear Information System (INIS)

    AiRuhaimi, K; Nwoku, A. L; Shaikh, H. S

    1991-01-01

    Almost all conferences for plastic and maxillofacial surgery discuss reports on several methods of orthognathic surgery, planning, success results, and complications of the different procedures carried out to correct patient's soft and hard tissues frontal profiles and occlusal discrepancies. Various principles are involved in the diagnosis and treatment of facial deformities. However, the most important consideration, after all, is the final accepted aesthetic and functional requirements and stability of the moved segments. The objective of this paper is to give the basic principles of treatment planning for correcting facial discrepancies, surgical approach to different cases, and the methods to increase stability of the moved segments. Six cases are included to illustrate the different aspects of treatment planning, surgical management, and stabilization methods. (author)

  8. Multi types DG expansion dynamic planning in distribution system under stochastic conditions using Covariance Matrix Adaptation Evolutionary Strategy and Monte-Carlo simulation

    International Nuclear Information System (INIS)

    Sadeghi, Mahmood; Kalantar, Mohsen

    2014-01-01

    Highlights: • Defining a DG dynamic planning problem. • Applying a new evolutionary algorithm called “CMAES” in planning process. • Considering electricity price and fuel price variation stochastic conditions. • Scenario generation and reduction with MCS and backward reduction programs. • Considering approximately all of the costs of the distribution system. - Abstract: This paper presents a dynamic DG planning problem considering uncertainties related to the intermittent nature of the DG technologies such as wind turbines and solar units in addition to the stochastic economic conditions. The stochastic economic situation includes the uncertainties related to the fuel and electricity price of each year. The Monte Carlo simulation is used to generate the possible scenarios of uncertain situations and the produced scenarios are reduced through backward reduction program. The aim of this paper is to maximize the revenue of the distribution system through the benefit cost analysis alongside the encouraging and punishment functions. In order to close to reality, the different growth rates for the planning period are selected. In this paper the Covariance Matrix Adaptation Evolutionary Strategy is introduced and is used to find the best planning scheme of the DG units. The different DG types are considered in the planning problem. The main assumption of this paper is that the DISCO is the owner of the distribution system and the DG units. The proposed method is tested on a 9 bus test distribution system and the results are compared with the known genetic algorithm and PSO methods to show the applicability of the CMAES method in this problem

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

    Energy Technology Data Exchange (ETDEWEB)

    D`Amelio, J.

    1994-08-30

    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.

  10. 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

  11. Towards the Validation of a Commercial Hyperthermia Treatment Planning System

    Science.gov (United States)

    Li, Zhen; Vogel, Martin; Maccarini, Paolo F.; Arabe, Omar A.; Stakhursky, Vadim; Crawford, Devin

    2013-01-01

    Recent developments have reinvigorated clinical investigations of hyperthermia (HT) as a viable adjuvant treatment in the fight against cancer. Researchers are placing a greater emphasis on multi-modal approaches that include mild temperatures (40°C – 43°C) and standard therapies like radiation and chemotherapy than on achieving higher temperature treatments (43°C-45°C) which were pursued in the past. The emergence of robust computer simulation tools for accurate hyperthermia treatment planning has aided this resurgence by helping improve the quality of heating. This article outlines a recent collaborative study at Duke University to demonstrate the capabilities of a new suite of 3D electromagnetic and thermodynamic simulation tools for treatment planning of external hyperthermia treatments with a radio frequency (RF) phased array heat applicator. Following a brief introduction to the rationale for moderate temperature hyperthermia and current methodology for heating tissue at depth in the body, the article will present a new approach for improved heating based on treatment planning with electromagnetic simulation software tools. Procedures, benefits, and a comparison of simulated heating patterns with those measured in two clinical hyperthermia treatments of advanced fibrous histiocytoma (soft-tissue sarcoma) tumors will be presented PMID:25324585

  12. BDTPS The BNCT Treatment Planning System jointly developed at DIMNP and JRC/IE

    CERN Document Server

    Daquino, G G; Mazzini, M; Moss, R; Muzi, L; International Workshop on "Neutron Capture Therapy: State of the art"

    2003-01-01

    The idea to couple the Treatment Planning System (TPS) to the information on the real boron distribution in the patient is the main added value of the new methodology set-up at DIMNP of University of Pisa, in collaboration with the JRC of Petten (NL). The methodology has been implemented in the new TPS, called BDTPS (Boron Distribution Treatment Planning System), which takes into account the actual boron distribution in the patient brain, while the standard TPS assumes a uniform boron distribution, absolutely far from the reality. Nowadays, Positron Emission Tomography (PET) is able to provide this in vivo information. The new TPS, based on the Monte Carlo technique, has been validated comparing the main BNCT parameters (thermal flux, boron dose, etc.) as measured during the irradiation of a special heterogeneous boron phantom (HEBOM), ad hoc designed, as calculated by the BDTPS and by the standard TPS SERA. An evident SERA overestimation of the thermal neutron flux, as well as the boron dose, has been detect...

  13. Automatic treatment plan re-optimization for adaptive radiotherapy guided with the initial plan DVHs.

    Science.gov (United States)

    Li, Nan; Zarepisheh, Masoud; Uribe-Sanchez, Andres; Moore, Kevin; Tian, Zhen; Zhen, Xin; Graves, Yan Jiang; Gautier, Quentin; Mell, Loren; Zhou, Linghong; Jia, Xun; Jiang, Steve

    2013-12-21

    Adaptive radiation therapy (ART) can reduce normal tissue toxicity and/or improve tumor control through treatment adaptations based on the current patient anatomy. Developing an efficient and effective re-planning algorithm is an important step toward the clinical realization of ART. For the re-planning process, manual trial-and-error approach to fine-tune planning parameters is time-consuming and is usually considered unpractical, especially for online ART. It is desirable to automate this step to yield a plan of acceptable quality with minimal interventions. In ART, prior information in the original plan is available, such as dose-volume histogram (DVH), which can be employed to facilitate the automatic re-planning process. The goal of this work is to develop an automatic re-planning algorithm to generate a plan with similar, or possibly better, DVH curves compared with the clinically delivered original plan. Specifically, our algorithm iterates the following two loops. An inner loop is the traditional fluence map optimization, in which we optimize a quadratic objective function penalizing the deviation of the dose received by each voxel from its prescribed or threshold dose with a set of fixed voxel weighting factors. In outer loop, the voxel weighting factors in the objective function are adjusted according to the deviation of the current DVH curves from those in the original plan. The process is repeated until the DVH curves are acceptable or maximum iteration step is reached. The whole algorithm is implemented on GPU for high efficiency. The feasibility of our algorithm has been demonstrated with three head-and-neck cancer IMRT cases, each having an initial planning CT scan and another treatment CT scan acquired in the middle of treatment course. Compared with the DVH curves in the original plan, the DVH curves in the resulting plan using our algorithm with 30 iterations are better for almost all structures. The re-optimization process takes about 30 s using

  14. Automatic treatment plan re-optimization for adaptive radiotherapy guided with the initial plan DVHs

    Science.gov (United States)

    Li, Nan; Zarepisheh, Masoud; Uribe-Sanchez, Andres; Moore, Kevin; Tian, Zhen; Zhen, Xin; Jiang Graves, Yan; Gautier, Quentin; Mell, Loren; Zhou, Linghong; Jia, Xun; Jiang, Steve

    2013-12-01

    Adaptive radiation therapy (ART) can reduce normal tissue toxicity and/or improve tumor control through treatment adaptations based on the current patient anatomy. Developing an efficient and effective re-planning algorithm is an important step toward the clinical realization of ART. For the re-planning process, manual trial-and-error approach to fine-tune planning parameters is time-consuming and is usually considered unpractical, especially for online ART. It is desirable to automate this step to yield a plan of acceptable quality with minimal interventions. In ART, prior information in the original plan is available, such as dose-volume histogram (DVH), which can be employed to facilitate the automatic re-planning process. The goal of this work is to develop an automatic re-planning algorithm to generate a plan with similar, or possibly better, DVH curves compared with the clinically delivered original plan. Specifically, our algorithm iterates the following two loops. An inner loop is the traditional fluence map optimization, in which we optimize a quadratic objective function penalizing the deviation of the dose received by each voxel from its prescribed or threshold dose with a set of fixed voxel weighting factors. In outer loop, the voxel weighting factors in the objective function are adjusted according to the deviation of the current DVH curves from those in the original plan. The process is repeated until the DVH curves are acceptable or maximum iteration step is reached. The whole algorithm is implemented on GPU for high efficiency. The feasibility of our algorithm has been demonstrated with three head-and-neck cancer IMRT cases, each having an initial planning CT scan and another treatment CT scan acquired in the middle of treatment course. Compared with the DVH curves in the original plan, the DVH curves in the resulting plan using our algorithm with 30 iterations are better for almost all structures. The re-optimization process takes about 30 s using

  15. Automatic treatment plan re-optimization for adaptive radiotherapy guided with the initial plan DVHs

    International Nuclear Information System (INIS)

    Li, Nan; Zarepisheh, Masoud; Uribe-Sanchez, Andres; Moore, Kevin; Tian, Zhen; Zhen, Xin; Graves, Yan Jiang; Gautier, Quentin; Mell, Loren; Jia, Xun; Jiang, Steve; Zhou, Linghong

    2013-01-01

    Adaptive radiation therapy (ART) can reduce normal tissue toxicity and/or improve tumor control through treatment adaptations based on the current patient anatomy. Developing an efficient and effective re-planning algorithm is an important step toward the clinical realization of ART. For the re-planning process, manual trial-and-error approach to fine-tune planning parameters is time-consuming and is usually considered unpractical, especially for online ART. It is desirable to automate this step to yield a plan of acceptable quality with minimal interventions. In ART, prior information in the original plan is available, such as dose–volume histogram (DVH), which can be employed to facilitate the automatic re-planning process. The goal of this work is to develop an automatic re-planning algorithm to generate a plan with similar, or possibly better, DVH curves compared with the clinically delivered original plan. Specifically, our algorithm iterates the following two loops. An inner loop is the traditional fluence map optimization, in which we optimize a quadratic objective function penalizing the deviation of the dose received by each voxel from its prescribed or threshold dose with a set of fixed voxel weighting factors. In outer loop, the voxel weighting factors in the objective function are adjusted according to the deviation of the current DVH curves from those in the original plan. The process is repeated until the DVH curves are acceptable or maximum iteration step is reached. The whole algorithm is implemented on GPU for high efficiency. The feasibility of our algorithm has been demonstrated with three head-and-neck cancer IMRT cases, each having an initial planning CT scan and another treatment CT scan acquired in the middle of treatment course. Compared with the DVH curves in the original plan, the DVH curves in the resulting plan using our algorithm with 30 iterations are better for almost all structures. The re-optimization process takes about 30

  16. New paradigms in prosthodontic treatment planning: a literature review.

    Science.gov (United States)

    Rich, Benedict; Goldstein, Gary R

    2002-08-01

    New treatment modalities have expanded the choices available to prosthodontists and their patients. At the same time, an explosion of data has called into question the validity and efficacy of certain forms of traditional prosthodontic treatment. Together, these factors have greatly complicated the treatment-planning process. The purpose of this article is to provide a framework for the prosthodontic treatment-planning process that incorporates the latest evidence-based information available. A review of the literature was undertaken through a Medline search. Articles published in English from 1975 through 2001 were evaluated; selected articles were chosen for review on the basis of a subjective judgment of their relevancy and significance to the clinician.

  17. Monte Carlo simulation to study the doses in an accelerator BNCT treatment

    International Nuclear Information System (INIS)

    Burlon, Alejandro A.; Valda, Alejandro A.; Somacal, Hector R.; Kreiner, Andres J.; Minsky, Daniel M.

    2003-01-01

    In this work the 7 Li(p, n) 7 Be reaction has been studied as a neutron source for accelerator-based BNCT (Boron Neutron Capture Therapy). In order to optimize the design of the neutron production target and the beam shaping assembly, extensive MCNP simulations have been performed. These simulations include a thick Li metal target, a whole-body phantom, a moderator-reflector assembly (Al/AlF 3 as moderator and graphite as reflector) and the treatment room. The doses were evaluated for two proton bombarding energies of 1.92 MeV (near to the threshold of the reaction) and 2.3 MeV (near to the resonance of the reaction) and for three Al/ALF 3 moderator thicknesses (18, 26 and 34 cm). To assess the doses, a comparison using a Tumor Control Probability (TCP) model was done. In a second instance, the effect of the specific skin radiosensitivity (an RBE of 2.5 for the 10 B(n,α) 7 Li reaction) and a 10 B uptake of 17 ppm was considered for the scalp. Finally, the simulations show the advantage of irradiating with near-resonance-energy protons (2.3 MeV) because of the high neutron yield at this energy, leading to the lowest treatment times. Moreover, the 26 cm Al/AlF 3 moderator has shown the best performance among the studied cases. (author)

  18. 3718-F Alkali Metal Treatment and Storage Facility Closure Plan

    Energy Technology Data Exchange (ETDEWEB)

    None

    1991-12-01

    Since 1987, Westinghouse Hanford Company has been a major contractor to the U.S. Department of Energy-Richland Operations Office and has served as co-operator of the 3718-F Alkali Metal Treatment and Storage Facility, the waste management unit addressed in this closure plan. The closure plan consists of a Part A Dangerous waste Permit Application and a RCRA Closure Plan. An explanation of the Part A Revision (Revision 1) submitted with this document is provided at the beginning of the Part A section. The closure plan consists of 9 chapters and 5 appendices. The chapters cover: introduction; facility description; process information; waste characteristics; groundwater; closure strategy and performance standards; closure activities; postclosure; and references.

  19. Treatment planning aspects for tumours in the region of parotid

    International Nuclear Information System (INIS)

    Narayanan, S.S.; Saju, Sherly; Deshpande, D.D.; Agarwal, J.P.; Dinshaw, K.A.

    2001-01-01

    The treatment of carcinoma of parotid/external ear needs careful planning in respect of dose to the normal organs surrounding the tumour such as eye(s), pituitary and normal brain. In many centres, generally, manual contours are generated for a two dimensional planning, wherein Anterior-Posterior (A-P) oblique fields (patient in Lateral Position) are planned. However, such a field orientation is not always useful in terms of minimum possible dose to the said normal organs, especially for eye. In this centre, a different field arrangement has been attempted, which helps in dose reduction to the normal structures to a large extent in comparison with the conventional 2D planning method

  20. 3718-F Alkali Metal Treatment and Storage Facility Closure Plan

    International Nuclear Information System (INIS)

    1991-12-01

    Since 1987, Westinghouse Hanford Company has been a major contractor to the U.S. Department of Energy-Richland Operations Office and has served as co-operator of the 3718-F Alkali Metal Treatment and Storage Facility, the waste management unit addressed in this closure plan. The closure plan consists of a Part A Dangerous waste Permit Application and a RCRA Closure Plan. An explanation of the Part A Revision (Revision 1) submitted with this document is provided at the beginning of the Part A section. The closure plan consists of 9 chapters and 5 appendices. The chapters cover: introduction; facility description; process information; waste characteristics; groundwater; closure strategy and performance standards; closure activities; postclosure; and references

  1. [Treatment of removable partial dentures. 1. Legislation, rules of conduct, care plan and treatment plan

    NARCIS (Netherlands)

    Witter, D.J.; Brands, W.G.; Barl, J.C.; Creugers, N.H.J.

    2011-01-01

    An invasive treatment, such as the treatment involving a removable partial denture, requires a well-structured approach. Regulations governing the communication between a healthcare professional and a patient in the Netherlands can be found in the Dutch Medical Treatment Act and the Rules of Conduct

  2. Uncertainties in model-based outcome predictions for treatment planning

    International Nuclear Information System (INIS)

    Deasy, Joseph O.; Chao, K.S. Clifford; Markman, Jerry

    2001-01-01

    Purpose: Model-based treatment-plan-specific outcome predictions (such as normal tissue complication probability [NTCP] or the relative reduction in salivary function) are typically presented without reference to underlying uncertainties. We provide a method to assess the reliability of treatment-plan-specific dose-volume outcome model predictions. Methods and Materials: A practical method is proposed for evaluating model prediction based on the original input data together with bootstrap-based estimates of parameter uncertainties. The general framework is applicable to continuous variable predictions (e.g., prediction of long-term salivary function) and dichotomous variable predictions (e.g., tumor control probability [TCP] or NTCP). Using bootstrap resampling, a histogram of the likelihood of alternative parameter values is generated. For a given patient and treatment plan we generate a histogram of alternative model results by computing the model predicted outcome for each parameter set in the bootstrap list. Residual uncertainty ('noise') is accounted for by adding a random component to the computed outcome values. The residual noise distribution is estimated from the original fit between model predictions and patient data. Results: The method is demonstrated using a continuous-endpoint model to predict long-term salivary function for head-and-neck cancer patients. Histograms represent the probabilities for the level of posttreatment salivary function based on the input clinical data, the salivary function model, and the three-dimensional dose distribution. For some patients there is significant uncertainty in the prediction of xerostomia, whereas for other patients the predictions are expected to be more reliable. In contrast, TCP and NTCP endpoints are dichotomous, and parameter uncertainties should be folded directly into the estimated probabilities, thereby improving the accuracy of the estimates. Using bootstrap parameter estimates, competing treatment

  3. [Endodontically treated teeth. Success--failure. Endorestorative treatment plan].

    Science.gov (United States)

    Zabalegui, B

    1990-01-01

    More and more often the general dentist is finding the presence of endodontically treated teeth during his treatment planning procedure. He has to ask himself if the endo-treated tooth functions and will continue to function function successfully, when deciding which final endo-restorative procedure to apply. For this reason the dentist or the endodontist with whom he works should clinically evaluate these teeth, establish a diagnostic criteria of their success or failure and a treatment plan according to the prognosis. The purpose of this article is to offer an organized clinical view of the steps to follow when evaluating an endodontically treated tooth and how to establish a final endo-restorative plan.

  4. Robust optimization in lung treatment plans accounting for geometric uncertainty.

    Science.gov (United States)

    Zhang, Xin; Rong, Yi; Morrill, Steven; Fang, Jian; Narayanasamy, Ganesh; Galhardo, Edvaldo; Maraboyina, Sanjay; Croft, Christopher; Xia, Fen; Penagaricano, Jose

    2018-03-10

    Robust optimization generates scenario-based plans by a minimax optimization method to find optimal scenario for the trade-off between target coverage robustness and organ-at-risk (OAR) sparing. In this study, 20 lung cancer patients with tumors located at various anatomical regions within the lungs were selected and robust optimization photon treatment plans including intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) plans were generated. The plan robustness was analyzed using perturbed doses with setup error boundary of ±3 mm in anterior/posterior (AP), ±3 mm in left/right (LR), and ±5 mm in inferior/superior (IS) directions from isocenter. Perturbed doses for D 99 , D 98 , and D 95 were computed from six shifted isocenter plans to evaluate plan robustness. Dosimetric study was performed to compare the internal target volume-based robust optimization plans (ITV-IMRT and ITV-VMAT) and conventional PTV margin-based plans (PTV-IMRT and PTV-VMAT). The dosimetric comparison parameters were: ITV target mean dose (D mean ), R 95 (D 95 /D prescription ), Paddick's conformity index (CI), homogeneity index (HI), monitor unit (MU), and OAR doses including lung (D mean , V 20 Gy and V 15 Gy ), chest wall, heart, esophagus, and maximum cord doses. A comparison of optimization results showed the robust optimization plan had better ITV dose coverage, better CI, worse HI, and lower OAR doses than conventional PTV margin-based plans. Plan robustness evaluation showed that the perturbed doses of D 99 , D 98 , and D 95 were all satisfied at least 99% of the ITV to received 95% of prescription doses. It was also observed that PTV margin-based plans had higher MU than robust optimization plans. The results also showed robust optimization can generate plans that offer increased OAR sparing, especially for normal lungs and OARs near or abutting the target. Weak correlation was found between normal lung dose and target size, and no other correlation

  5. A simple planning technique of craniospinal irradiation in the eclipse treatment planning system

    Directory of Open Access Journals (Sweden)

    Hemalatha Athiyaman

    2014-01-01

    Full Text Available A new planning method for Craniospinal Irradiation by Eclipse treatment planning system using Field alignment, Field-in-Field technique was developed. Advantage of this planning method was also studied retrospectively for previously treated five patients of medulloblastoma with variable spine length. Plan consists of half beam blocked parallel opposed cranium, and a single posterior cervicospine field was created by sharing the same isocenter, which obviates divergence matching. Further, a single symmetrical field was created to treat remaining Lumbosacral spine. Matching between a inferior diverging edge of cervicospine field and superior diverging edge of a Lumbosacral field was done using the field alignment option. ′Field alignment′ is specific option in the Eclipse Treatment Planning System, which automatically matches the field edge divergence as per field alignment rule. Multiple segments were applied in both the spine field to manage with hot and cold spots created by varying depth of spinal cord. Plan becomes fully computerized using this field alignment option and multiple segments. Plan evaluation and calculated mean modified Homogeneity Index (1.04 and 0.1 ensured that dose to target volume is homogeneous and critical organ doses were within tolerance. Dose variation at the spinal field junction was verified using ionization chamber array (I′MatriXX for matched, overlapped and gap junction spine fields; the delivered dose distribution confirmed the ideal clinical match, over exposure and under exposure at the junction, respectively. This method is simple to plan, executable in Record and Verify mode and can be adopted for various length of spinal cord with only two isocenter in shorter treatment time.

  6. The Use of Videotapes in Treatment Plan Presentation Seminars.

    Science.gov (United States)

    Powell, Billy J.; And Others

    1987-01-01

    A well-received third-year seminar in dental treatment plan presentation used videotaping of student presentations for self- and peer-evaluation. Students liked the faculty-student interaction and the feedback provided in the seminar, but many felt it would be more helpful if offered earlier in the curriculum. The evaluation form is included. (MSE)

  7. 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

  8. 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

  9. 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.

  10. Interocclusal Registration for Diagnosis and Treatment Planning for ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... implant case where multiple posterior teeth are missing and need to be replaced by implant restorations. In the case ... Keywords: Interocclusal Records, Diagnosis and Treatment Plan, Implant. Restorations. Interocclusal ... then removed to leave a window in the acrylic resin. The appliance was finished ...

  11. Incorrect dosimetric leaf separation in IMRT and VMAT treatment planning

    DEFF Research Database (Denmark)

    Sjölin, Maria; Edmund, Jens Morgenthaler

    2016-01-01

    PURPOSE: Dynamic treatment planning algorithms use a dosimetric leaf separation (DLS) parameter to model the multi-leaf collimator (MLC) characteristics. Here, we quantify the dosimetric impact of an incorrect DLS parameter and investigate whether common pretreatment quality assurance (QA) method...

  12. Brachytherapy treatment planning algorithm applied to prostate cancer

    Science.gov (United States)

    Herrera-Rodríguez, M. R.; Martínez-Dávalos, A.

    2000-10-01

    An application of Genetic Algorithms (GAs) for treatment planning optimization in prostate brachytherapy is presented. The importance of multi-objective selection criteria based on the contour of the volume of interest and radiosensitive structures such as the rectum and urethra is discussed. First results are obtained for a simple test case which presents radial symmetry.

  13. Savannah River Site Approved Site Treatment Plan, 1998 Annual Update

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, B.

    1999-04-20

    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.

  14. Treatment optimization of a brain tumor in BNCT by Monte Carlo method

    International Nuclear Information System (INIS)

    Nejat, S.; Binesh, A.; Karimian, A.

    2012-01-01

    Brain cancers are one of the most important diseases. BNCT (Boron Neutron Capture Therapy) is used to brain tumor treatment. In this method the 1 0B (n,α) 7 Li reaction is used. The purpose of this study is absorbed dose evaluation of tumoral and healthy parts of brain. To achieve this aim the brain was simulated by a cylindrical phantom with the dimensions of 20 cm in diameter and height. In BNCT treatment the BSH (Na 2 B 12 H 11 SH) is injected to the human body and absorbed in the healthy and tumoral parts by the ratios of 18 and 65 ppm respectively. So in this research the absorption of BSH in tumoral and healthy parts of brain was considered as the mentioned ratio. Then the neutron with the energy range of 50 eV - 10 keV was exposed to the brain and maximum absorbed dose in healthy and tumoral parts of brain were calculated for a cylindrical tumor with the thickness of about 1 cm which was considered in 5.5 cm depth of brain. This research showed the suitable energy to treat this tumor by BNCT is interval 4 keV- 6keV. The average of dose which is met with healthy and tumor tissue was gained for 6 keV energy of brain 1.18x10 -12 cGy/n and 5.98x10 -12 cGy/n respectively. Maximum of dose which is met with healthy tissue was 4.3 Gy which is much less than standard amount 12.6 Gy. Therefore BNCT method is known as an effective way in the therapy of this kind of tumor. (authors)

  15. Probabilistic Analysis for Capacity Planning in Smart Grid at Residential Low Voltage Level by Monte-Carlo Method

    NARCIS (Netherlands)

    Du, W.

    2011-01-01

    Smart Grid integrates sustainable energy sources and allows mutual communications between electricity distribution operators and electricity consumers. Electricity demand and supply becomes more complex in Smart Grid. It is more challenging for DNOs in grid asset capacity planning, especially at low

  16. 4D Proton treatment planning strategy for mobile lung tumors

    International Nuclear Information System (INIS)

    Kang Yixiu; Zhang Xiaodong; Chang, Joe Y.; Wang He; Wei Xiong; Liao Zhongxing; Komaki, Ritsuko; Cox, James D.; Balter, Peter A.; Liu, Helen; Zhu, X. Ronald; Mohan, Radhe; Dong Lei

    2007-01-01

    Purpose: To investigate strategies for designing compensator-based 3D proton treatment plans for mobile lung tumors using four-dimensional computed tomography (4DCT) images. Methods and Materials: Four-dimensional CT sets for 10 lung cancer patients were used in this study. The internal gross tumor volume (IGTV) was obtained by combining the tumor volumes at different phases of the respiratory cycle. For each patient, we evaluated four planning strategies based on the following dose calculations: (1) the average (AVE) CT; (2) the free-breathing (FB) CT; (3) the maximum intensity projection (MIP) CT; and (4) the AVE CT in which the CT voxel values inside the IGTV were replaced by a constant density (AVE R IGTV). For each strategy, the resulting cumulative dose distribution in a respiratory cycle was determined using a deformable image registration method. Results: There were dosimetric differences between the apparent dose distribution, calculated on a single CT dataset, and the motion-corrected 4D dose distribution, calculated by combining dose distributions delivered to each phase of the 4DCT. The AVE R IGTV plan using a 1-cm smearing parameter had the best overall target coverage and critical structure sparing. The MIP plan approach resulted in an unnecessarily large treatment volume. The AVE and FB plans using 1-cm smearing did not provide adequate 4D target coverage in all patients. By using a larger smearing value, adequate 4D target coverage could be achieved; however, critical organ doses were increased. Conclusion: The AVE R IGTV approach is an effective strategy for designing proton treatment plans for mobile lung tumors

  17. 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

  18. Savannah River Site Approved Site Treatment Plan, 1998 Annual Update

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, B. [Westinghouse Savannah River Company, AIKEN, SC (United States); Berry, M.

    1998-03-01

    The U.S. 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 I. 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 I) 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 II) and is provided for information.

  19. 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.

  20. Dosimetry and treatment planning of Occu-Prosta 125I seeds for intraocular lesions

    International Nuclear Information System (INIS)

    Chaudhari, Suresh; Deshpande, Sudesh; Anand, Vivek; De, Sandeep; Kannan, V.; Saxena, Sanjay; Dash, A.; Basu, Mahua; Samant, Preetam

    2008-01-01

    Intraocular malignant lesions are frequently encountered in clinical practice. Plaque brachytherapy represents an effective means of treatment for intraocular lesions. Recently Radiopharmaceutical Division, BARC, Mumbai, has indigenously fabricated reasonable-cost 125 I sources. Here we are presenting the preliminary experience of dosimetry of sources, configuration of treatment planning system (TPS) and quality assurance (QA) for eye plaque therapy with Occu-Prosta 125 I seeds, treated in our hospital, for a patient with ocular lesions. 125 I seeds were calibrated using well-type chamber. BrachyVision TPS was configured with Monte Carlo computed radial dose functions and anisotropy functions for 125 I sources. Dose calculated by TPS at different points in central axis and off axis was compared with manually calculated dose. Eye plaque was fabricated of 17 karat pure gold, locally. The seeds were arranged in an outer ring near the edge of the plaque and in concentric rings throughout the plaque. The sources were manually digitized on the TPS, and dose distribution was calculated in three dimensions. Measured activity using cross-calibrated well-type chamber was within ± 10% of the activity specified by the supplier. Difference in TPS-calculated dose and manually calculated dose was within 5%. Treatment time calculated by TPS was in concordance with published data for similar plaque arrangement. (author)

  1. The role of Cobalt-60 source in Intensity Modulated Radiation Therapy: From modeling finite sources to treatment planning and conformal dose delivery

    Science.gov (United States)

    Dhanesar, Sandeep Kaur

    Cobalt-60 (Co-60) units played an integral role in radiation therapy from the mid-1950s to the 1970s. Although they continue to be used to treat cancer in some parts of the world, their role has been significantly reduced due to the invention of medical linear accelerators. A number of groups have indicated a strong potential for Co-60 units in modern radiation therapy. The Medical Physics group at the Cancer Center of the Southeastern Ontario and Queen's University has shown the feasibility of Intensity Modulated Radiation Therapy (IMRT) via simple conformal treatment planning and dose delivery using a Co-60 unit. In this thesis, initial Co-60 tomotherapy planning investigations on simple uniform phantoms are extended to actual clinical cases based on patient CT data. The planning is based on radiation dose data from a clinical Co-60 unit fitted with a multileaf collimator (MLC) and modeled in the EGSnrc Monte Carlo system. An in house treatment planning program is used to calculate IMRT dose distributions. Conformal delivery in a single slice on a uniform phantom based on sequentially delivered pencil beams is verified by Gafchromic film. Volumetric dose distributions for Co-60 serial tomotherapy are then generated for typical clinical sites that had been treated at our clinic by conventional 6MV IMRT using Varian Eclipse treatment plans. The Co-60 treatment plans are compared with the clinical IMRT plans using conventional matrices such as dose volume histograms (DVH). Dose delivery based on simultaneously opened MLC leaves is also explored and a novel MLC segmentation method is proposed. In order to increase efficiency of dose calculations, a novel convolution based fluence model for treatment planning is also proposed. The ion chamber measurements showed that the Monte Carlo modeling of the beam data under the MIMiC MLC is accurate. The film measurements from the uniform phantom irradiations confirm that IMRT plans from our in-house treatment planning system

  2. Very fast simulated reannealing in radiation therapy treatment plan optimization

    International Nuclear Information System (INIS)

    Morrill, Steven M.; Lam, Kam Shing; Lane, Richard G.; Langer, Mark; Rosen, Isaac I.

    1995-01-01

    Purpose: Very Fast Simulated Reannealing is a relatively new (1989) and sophisticated algorithm for simulated annealing applications. It offers the advantages of annealing methods while requiring shorter execution times. The purpose of this investigation was to adapt Very Fast Simulated Reannealing to conformal treatment planning optimization. Methods and Materials: We used Very Fast Simulated Reannealing to optimize treatments for three clinical cases with two different cost functions. The first cost function was linear (minimum target dose) with nonlinear dose-volume normal tissue constraints. The second cost function (probability of uncomplicated local control) was a weighted product of normal tissue complication probabilities and the tumor control probability. Results: For the cost functions used in this study, the Very Fast Simulated Reannealing algorithm achieved results within 5-10% of the final solution (100,000 iterations) after 1000 iterations and within 3-5% of the final solution after 5000-10000 iterations. These solutions were superior to those produced by a conventional treatment plan based on an analysis of the resulting dose-volume histograms. However, this technique is a stochastic method and results vary in a statistical manner. Successive solutions may differ by up to 10%. Conclusion: Very Fast Simulated Reannealing, with modifications, is suitable for radiation therapy treatment planning optimization. It produced results within 3-10% of the optimal solution, produced using another optimization algorithm (Mixed Integer Programming), in clinically useful execution times

  3. Total skin electron therapy treatment verification: Monte Carlo simulation and beam characteristics of large non-standard electron fields

    International Nuclear Information System (INIS)

    Pavon, Ester Carrasco; Sanchez-Doblado, Francisco; Leal, Antonio; Capote, Roberto; Lagares, Juan Ignacio; Perucha, Maria; Arrans, Rafael

    2003-01-01

    Total skin electron therapy (TSET) is a complex technique which requires non-standard measurements and dosimetric procedures. This paper investigates an essential first step towards TSET Monte Carlo (MC) verification. The non-standard 6 MeV 40 x 40 cm 2 electron beam at a source to surface distance (SSD) of 100 cm as well as its horizontal projection behind a polymethylmethacrylate (PMMA) screen to SSD = 380 cm were evaluated. The EGS4 OMEGA-BEAM code package running on a Linux home made 47 PCs cluster was used for the MC simulations. Percentage depth-dose curves and profiles were calculated and measured experimentally for the 40 x 40 cm 2 field at both SSD = 100 cm and patient surface SSD = 380 cm. The output factor (OF) between the reference 40 x 40 cm 2 open field and its horizontal projection as TSET beam at SSD = 380 cm was also measured for comparison with MC results. The accuracy of the simulated beam was validated by the good agreement to within 2% between measured relative dose distributions, including the beam characteristic parameters (R 50 , R 80 , R 100 , R p , E 0 ) and the MC calculated results. The energy spectrum, fluence and angular distribution at different stages of the beam (at SSD = 100 cm, at SSD = 364.2 cm, behind the PMMA beam spoiler screen and at treatment surface SSD = 380 cm) were derived from MC simulations. Results showed a final decrease in mean energy of almost 56% from the exit window to the treatment surface. A broader angular distribution (FWHM of the angular distribution increased from 13deg at SSD 100 cm to more than 30deg at the treatment surface) was fully attributable to the PMMA beam spoiler screen. OF calculations and measurements agreed to less than 1%. The effect of changing the electron energy cut-off from 0.7 MeV to 0.521 MeV and air density fluctuations in the bunker which could affect the MC results were shown to have a negligible impact on the beam fluence distributions. Results proved the applicability of using MC

  4. A treatment planning method for better management of radiation-induced oral mucositis in locally advanced head and neck cancer

    Directory of Open Access Journals (Sweden)

    Hao Howard Zhang

    2018-01-01

    Full Text Available Purpose/Aim: To describe a two-phase intensity-modulated radiation therapy (IMRT treatment planning approach, that is, promising for reduction of oral mucositis risk in locally advanced head-and-neck cancer. Materials and Methods: Ten locally advanced head-and-neck cancer patients who underwent RT were retrospectively collected. Conventional IMRT and volumetric-modulated arc therapy (VMAT plans were generated for these patients following clinical protocol. Following the first phase of generating conventional IMRT plans, our approach utilized data from Monte Carlo-based kernel superposition dose calculations corresponding to beam apertures (generated from the conventional IMRT plans and used an exact mathematical programming-based optimization approach applying linear programming (LP to dose optimization in the second phase. Results: Compared with conventional IMRT and VMAT treatment plans, our novel method achieved better preservation of oral cavity (16%–29% lower mean dose, P < 0.01, parotid glands (6%–17% lower mean dose, P < 0.04, and spinal cord (3-11 Gy lower maximum dose, P < 0.03 and lower doses to nonorgan-at-risk/nontarget normal tissues, with the same or better target coverage. Conclusions: Our LP-based method can be practically implemented in routine clinical use with a goal of limiting radiation-induced oral mucositis for head-and-neck cancer patients.

  5. SU-F-T-128: Dose-Volume Constraints for Particle Therapy Treatment Planning

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, R; Smith, W; Hendrickson, K; Meyer, J; Cao, N; Lee, E; Gopan, O; Sandison, G; Parvathaneni, U; Laramore, G [University of Washington, Seattle, WA (United States)

    2016-06-15

    Purpose: Determine equivalent Organ at Risk (OAR) tolerance dose (TD) constraints for MV x-rays and particle therapy. Methods: Equivalent TD estimates for MV x-rays are determined from an isoeffect, regression-analysis of published and in-house constraints for various fractionation schedules (n fractions). The analysis yields an estimate of (α/β) for an OAR. To determine equivalent particle therapy constraints, the MV x-ray TD(n) values are divided by the RBE for DSB induction (RBE{sub DSB}) or cell survival (RBE{sub S}). Estimates of (RBE{sub DSB}) are computed using the Monte Carlo Damage Simulation, and estimates of RBES are computed using the Repair-Misrepair-Fixation (RMF) model. A research build of the RayStation™ treatment planning system implementing the above model is used to estimate (RBE{sub DSB}) for OARs of interest in 16 proton therapy patient plans (head and neck, thorax, prostate and brain). Results: The analysis gives an (α/β) estimate of about 20 Gy for the trachea and heart and 2–4 Gy for the esophagus, spine, and brachial plexus. Extrapolation of MV x-ray constraints (n = 1) to fast neutrons using RBE{sub DSB} = 2.7 are in excellent agreement with clinical experience (n = 10 to 20). When conventional (n > 30) x-ray treatments are used as the reference radiation, fast neutron RBE increased to a maximum of 6. For comparison to a constant RBE of 1.1, the RayStation™ analysis gave estimates of proton RBE{sub DSB} from 1.03 to 1.33 for OARs of interest. Conclusion: The presented system of models is a convenient formalism to synthesize from multiple sources of information a set of self-consistent plan constraints for MV x-ray and hadron therapy treatments. Estimates of RBE{sub DSB} from the RayStation™ analysis differ substantially from 1.1 and vary among patients and treatment sites. A treatment planning system that incorporates patient and anatomy-specific corrections in proton RBE would create opportunities to increase the therapeutic

  6. Radiation treatment planning techniques for lymphoma of the stomach

    International Nuclear Information System (INIS)

    Della Biancia, Cesar; Hunt, Margie; Furhang, Eli; Wu, Elisa; Yahalom, Joachim

    2005-01-01

    Purpose: Involved-field radiation therapy of the stomach is often used in the curative treatment of gastric lymphoma. Yet, the optimal technique to irradiate the stomach with minimal morbidity has not been well established. This study was designed to evaluate treatment planning alternatives for stomach irradiation, including intensity-modulated radiation therapy (IMRT), to determine which approach resulted in improved dose distribution and to identify patient-specific anatomic factors that might influence a treatment planning choice. Methods and Materials: Fifteen patients with lymphoma of the stomach (14 mucosa-associated lymphoid tissue lymphomas and 1 diffuse large B-cell lymphoma) were categorized into 3 types, depending on the geometric relationship between the planning target volume (PTV) and kidneys. AP/PA and 3D conformal radiation therapy (3DCRT) plans were generated for each patient. IMRT was planned for 4 patients with challenging geometric relationship between the PTV and the kidneys to determine whether it was advantageous to use IMRT. Results: For type I patients (no overlap between PTV and kidneys), there was essentially no benefit from using 3DCRT over AP/PA. However, for patients with PTVs in close proximity to the kidneys (type II) or with high degree of overlap (type III), the 4-field 3DCRT plans were superior, reducing the kidney V 15Gy by approximately 90% for type II and 50% for type III patients. For type III, the use of a 3DCRT plan rather than an AP/PA plan decreased the V 15Gy by approximately 65% for the right kidney and 45% for the left kidney. In the selected cases, IMRT led to a further decrease in left kidney dose as well as in mean liver dose. Conclusions: The geometric relationship between the target and kidneys has a significant impact on the selection of the optimum beam arrangement. Using 4-field 3DCRT markedly decreases the kidney dose. The addition of IMRT led to further incremental improvements in the left kidney and liver

  7. Dosimetric calculations by Monte Carlo for treatments of radiosurgery with the Leksell Gamma Knife, homogeneous and non homogeneous cases; Calculos dosimetricos por Monte Carlo para tratamientos de radiocirugia con el Leksell Gamma Knife, casos homogeneo y no homogeneo

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E.L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Lallena R, A.M. [Universidad de Granada (Spain)

    2004-07-01

    In this work dose profiles are calculated that are obtained modeling treatments of radiosurgery with the Leksell Gamma Knife. This was made with the simulation code Monte Carlo Penelope for an homogeneous mannequin and one not homogeneous. Its were carried out calculations with the irradiation focus coinciding with the center of the mannequin as in near areas to the bone interface. Each one of the calculations one carries out for the 4 skull treatment that it includes the Gamma Knife and using a model simplified of their 201 sources of {sup 60} Co. It was found that the dose profiles differ of the order of 2% when the isocenter coincides with the center of the mannequin and they ascend to near 5% when the isocenter moves toward the skull. (Author)

  8. Advanced care planning: the impact of Ceiling of Treatment plans in patients with Coordinate My Care.

    Science.gov (United States)

    Broadhurst, Helen Lucy; Droney, Joanne; Callender, Tom; Shaw, Amanda; Riley, Julia

    2018-03-22

    The aim of this evaluation is to describe the components and results of urgent care planning in Coordinate My Care (CMC), a digital clinical service for patients with life-limiting illness, for use if a patient is unable to make or express choices. Ceiling of treatment (CoT) plans were created detailing where the patient would like to receive their care and how aggressive medical interventions should be. A retrospective service evaluation was completed of all CMC records created between December 2015 and September 2016 (n=6854). CMC records were divided into two cohorts: those with a CoT plan and those without. The factors associated with these cohorts were reviewed including age, diagnosis, resuscitation status and preferences for place of death (PPD). Analysis of the non-mandatory free text section was carried out. Two-thirds of patients had recorded decisions about CoT. Regardless of which CoT option was chosen, for most patients, PPD was home or care home. Patients with a CoT plan were more likely to have a documented resuscitation status.Patients with a CoT were more likely to die in their PPD (82%vs71%, OR 1.79, pcare planning. Three facets of urgent care planning identified include PPD, CoT and resuscitation status. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. In Vivo Diode Dosimetry for Imrt Treatments Generated by Pinnacle Treatment Planning System

    International Nuclear Information System (INIS)

    Alaei, Parham; Higgins, Patrick D.; Gerbi, Bruce J.

    2009-01-01

    Dose verification using diodes has been proposed and used for intensity modulated radiation therapy (IMRT) treatments. We have previously evaluated diode response for IMRT deliveries planned with the Eclipse/Helios treatment planning system. The Pinnacle treatment planning system generates plans that are delivered in a different fashion than Eclipse. Whereas the Eclipse-generated segments are delivered in organized progression from one side of each field to the other, Pinnacle-generated segments are delivered in a much more randomized fashion to different areas within the field. This makes diode measurements at a point more challenging because the diode may be exposed fully or partially to multiple small segments during one single field's treatment as opposed to being exposed to very few segments scanning across the diode during an Eclipse-generated delivery. We have evaluated in vivo dosimetry for Pinnacle-generated IMRT plans and characterized the response of the diode to various size segments on phantom. We present results of patient measurements on approximately 300 fields, which show that 76% of measurements agree to within 10% of the treatment-plan generated calculated doses. Of the other 24%, about 11% are within 15% of the calculated dose. Comparison of these with phantom measurements indicates that many of the discrepancies are due to diode positioning on patients and increased diode response at short source-to-surface distances (SSDs), with the remainder attributable to other factors such as segment size and partial irradiation of the diode

  10. Patients with hip prosthesis: radiotherapy treatment planning considerations

    International Nuclear Information System (INIS)

    Ganesh, K.M.; Supe, Sanjay S.

    2000-01-01

    The number of patients with hip prosthesis undergoing radiotherapy for pelvic cancer worldwide is increasing. This might be of importance depending on the materials in the prosthesis and whether any of the treatment fields are involved in the prosthesis. Radiotherapy planning involving the pelvic region of patients having total hip prosthesis has been found to be difficult due to the effect of the prosthesis on the dose distribution. This review is intended to project dosimetric considerations and possible solutions to this uncommon problem

  11. Current status of quality assurance of treatment planning systems

    International Nuclear Information System (INIS)

    Mijnheer, B.J.

    1997-01-01

    A review is given of the current status of quality assurance of treatment planning systems. At this moment only one comprehensive report is available. In order to review national activities a questionnaire has been distributed amongst national societies of medical physicists. From the 23 responding countries, 8 indicated that only limited efforts are underway, 8 answered that a working group is evaluating their specific national requirements while in 5 countries a document is drafted. The highlights of these reports have been summarized. (author)

  12. Interactive treatment planning in toothwear: are we doing it right?

    Science.gov (United States)

    Eliyas, Shiyana; Shah, Kewal; Briggs, Peter F A

    2014-04-01

    Toothwear is now common, especially in younger patients, with high demand for the restoration of the damaged teeth which is likely to increase further over time. Fixed prosthodontic options range from direct composite resin to conventional tooth preparation and cemented indirect restorations. This paper summarizes the views of a variety of clinicians on a plan delivered to a patient with toothwear in secondary care and explores the possible reasons for the variation in decision-making in the treatment of toothwear. With levels of toothwear increasing, the clinician needs to be aware of the different treatment modalities which are appropriate.

  13. 3D Computer aided treatment planning in endodontics.

    Science.gov (United States)

    van der Meer, Wicher J; Vissink, Arjan; Ng, Yuan Ling; Gulabivala, Kishor

    2016-02-01

    Obliteration of the root canal system due to accelerated dentinogenesis and dystrophic calcification can challenge the achievement of root canal treatment goals. This paper describes the application of 3D digital mapping technology for predictable navigation of obliterated canal systems during root canal treatment to avoid iatrogenic damage of the root. Digital endodontic treatment planning for anterior teeth with severely obliterated root canal systems was accomplished with the aid of computer software, based on cone beam computer tomography (CBCT) scans and intra-oral scans of the dentition. On the basis of these scans, endodontic guides were created for the planned treatment through digital designing and rapid prototyping fabrication. The custom-made guides allowed for an uncomplicated and predictable canal location and management. The method of digital designing and rapid prototyping of endodontic guides allows for reliable and predictable location of root canals of teeth with calcifically metamorphosed root canal systems. The endodontic directional guide facilitates difficult endodontic treatments at little additional cost. Copyright © 2016. Published by Elsevier Ltd.

  14. Implementation of enhanced dynamic wedges in pinnacle treatment planning system

    International Nuclear Information System (INIS)

    Alaei, Parham; Higgins, Patrick D.; Gerbi, Bruce J.

    2005-01-01

    Enhanced dynamic wedges (EDW) provide many advantages over traditional hard wedges for linear accelerator treatments. Along with these advantages comes the responsibility of ensuring that this complex technology delivers the correct dose to patients. This involves determining the enhanced dynamic wedge factors for various field sizes and depths for use in the hand calculation of monitor units (MUs). The accurate representation of dynamic wedges in the treatment planning computer must also be ensured. This is required so that the final isodose distributions are correct and the MUs calculated by the treatment planning computer match those determined by hand calculation. We have commissioned and implemented the use of EDW in the Pinnacle radiation therapy planning system. The modeled dose profiles agree with the measured ones with a maximum difference of 2%. The MUs generated by Pinnacle are also within 2% of those calculated independently. The process of data collection and verification, beam modeling, and a discussion of a potential pitfall encountered in this process are presented in this paper

  15. Inclusion of geometric uncertainties in treatment plan evaluation

    International Nuclear Information System (INIS)

    Herk, Marcel van; Remeijer, Peter; Lebesque, Joos V.

    2002-01-01

    Purpose: To correctly evaluate realistic treatment plans in terms of absorbed dose to the clinical target volume (CTV), equivalent uniform dose (EUD), and tumor control probability (TCP) in the presence of execution (random) and preparation (systematic) geometric errors. Materials and Methods: The dose matrix is blurred with all execution errors to estimate the total dose distribution of all fractions. To include preparation errors, the CTV is randomly displaced (and optionally rotated) many times with respect to its planned position while computing the dose, EUD, and TCP for the CTV using the blurred dose matrix. Probability distributions of these parameters are computed by combining the results with the probability of each particular preparation error. We verified the method by comparing it with an analytic solution. Next, idealized and realistic prostate plans were tested with varying margins and varying execution and preparation error levels. Results: Probability levels for the minimum dose, computed with the new method, are within 1% of the analytic solution. The impact of rotations depends strongly on the CTV shape. A margin of 10 mm between the CTV and planning target volume is adequate for three-field prostate treatments given the accuracy level in our department; i.e., the TCP in a population of patients, TCP pop , is reduced by less than 1% due to geometric errors. When reducing the margin to 6 mm, the dose must be increased from 80 to 87 Gy to maintain the same TCP pop . Only in regions with a high-dose gradient does such a margin reduction lead to a decrease in normal tissue dose for the same TCP pop . Based on a rough correspondence of 84% minimum dose with 98% EUD, a margin recipe was defined. To give 90% of patients at least 98% EUD, the planning target volume margin must be approximately 2.5 Σ + 0.7 σ - 3 mm, where Σ and σ are the combined standard deviations of the preparation and execution errors. This recipe corresponds accurately with 1% TCP

  16. Radiotherapy beyond cancer: Target localization in real-time MRI and treatment planning for cardiac radiosurgery

    International Nuclear Information System (INIS)

    Ipsen, S.; Blanck, O.; Rades, D.; Oborn, B.; Bode, F.; Liney, G.; Hunold, P.; Schweikard, A.; Keall, P. J.

    2014-01-01

    Purpose: Atrial fibrillation (AFib) is the most common cardiac arrhythmia that affects millions of patients world-wide. AFib is usually treated with minimally invasive, time consuming catheter ablation techniques. While recently noninvasive radiosurgery to the pulmonary vein antrum (PVA) in the left atrium has been proposed for AFib treatment, precise target location during treatment is challenging due to complex respiratory and cardiac motion. A MRI linear accelerator (MRI-Linac) could solve the problems of motion tracking and compensation using real-time image guidance. In this study, the authors quantified target motion ranges on cardiac magnetic resonance imaging (MRI) and analyzed the dosimetric benefits of margin reduction assuming real-time motion compensation was applied. Methods: For the imaging study, six human subjects underwent real-time cardiac MRI under free breathing. The target motion was analyzed retrospectively using a template matching algorithm. The planning study was conducted on a CT of an AFib patient with a centrally located esophagus undergoing catheter ablation, representing an ideal case for cardiac radiosurgery. The target definition was similar to the ablation lesions at the PVA created during catheter treatment. Safety margins of 0 mm (perfect tracking) to 8 mm (untracked respiratory motion) were added to the target, defining the planning target volume (PTV). For each margin, a 30 Gy single fraction IMRT plan was generated. Additionally, the influence of 1 and 3 T magnetic fields on the treatment beam delivery was simulated using Monte Carlo calculations to determine the dosimetric impact of MRI guidance for two different Linac positions. Results: Real-time cardiac MRI showed mean respiratory target motion of 10.2 mm (superior–inferior), 2.4 mm (anterior–posterior), and 2 mm (left–right). The planning study showed that increasing safety margins to encompass untracked respiratory motion leads to overlapping structures even in the

  17. Radiotherapy beyond cancer: Target localization in real-time MRI and treatment planning for cardiac radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Ipsen, S. [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006, Australia and Institute for Robotics and Cognitive Systems, University of Luebeck, Luebeck 23562 (Germany); Blanck, O.; Rades, D. [Department of Radiation Oncology, University of Luebeck and University Medical Center Schleswig-Holstein, Campus Luebeck, Luebeck 23562 (Germany); Oborn, B. [Illawarra Cancer Care Centre (ICCC), Wollongong, New South Wales 2500, Australia and Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia); Bode, F. [Medical Department II, University of Luebeck and University Medical Center Schleswig-Holstein, Campus Luebeck, Luebeck 23562 (Germany); Liney, G. [Ingham Institute for Applied Medical Research, Liverpool Hospital, Liverpool, New South Wales 2170 (Australia); Hunold, P. [Department of Radiology and Nuclear Medicine, University of Luebeck and University Medical Center Schleswig-Holstein, Campus Luebeck, Luebeck 23562 (Germany); Schweikard, A. [Institute for Robotics and Cognitive Systems, University of Luebeck, Luebeck 23562 (Germany); Keall, P. J., E-mail: paul.keall@sydney.edu.au [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006 (Australia)

    2014-12-15

    Purpose: Atrial fibrillation (AFib) is the most common cardiac arrhythmia that affects millions of patients world-wide. AFib is usually treated with minimally invasive, time consuming catheter ablation techniques. While recently noninvasive radiosurgery to the pulmonary vein antrum (PVA) in the left atrium has been proposed for AFib treatment, precise target location during treatment is challenging due to complex respiratory and cardiac motion. A MRI linear accelerator (MRI-Linac) could solve the problems of motion tracking and compensation using real-time image guidance. In this study, the authors quantified target motion ranges on cardiac magnetic resonance imaging (MRI) and analyzed the dosimetric benefits of margin reduction assuming real-time motion compensation was applied. Methods: For the imaging study, six human subjects underwent real-time cardiac MRI under free breathing. The target motion was analyzed retrospectively using a template matching algorithm. The planning study was conducted on a CT of an AFib patient with a centrally located esophagus undergoing catheter ablation, representing an ideal case for cardiac radiosurgery. The target definition was similar to the ablation lesions at the PVA created during catheter treatment. Safety margins of 0 mm (perfect tracking) to 8 mm (untracked respiratory motion) were added to the target, defining the planning target volume (PTV). For each margin, a 30 Gy single fraction IMRT plan was generated. Additionally, the influence of 1 and 3 T magnetic fields on the treatment beam delivery was simulated using Monte Carlo calculations to determine the dosimetric impact of MRI guidance for two different Linac positions. Results: Real-time cardiac MRI showed mean respiratory target motion of 10.2 mm (superior–inferior), 2.4 mm (anterior–posterior), and 2 mm (left–right). The planning study showed that increasing safety margins to encompass untracked respiratory motion leads to overlapping structures even in the

  18. Radiotherapy beyond cancer: target localization in real-time MRI and treatment planning for cardiac radiosurgery.

    Science.gov (United States)

    Ipsen, S; Blanck, O; Oborn, B; Bode, F; Liney, G; Hunold, P; Rades, D; Schweikard, A; Keall, P J

    2014-12-01

    Atrial fibrillation (AFib) is the most common cardiac arrhythmia that affects millions of patients world-wide. AFib is usually treated with minimally invasive, time consuming catheter ablation techniques. While recently noninvasive radiosurgery to the pulmonary vein antrum (PVA) in the left atrium has been proposed for AFib treatment, precise target location during treatment is challenging due to complex respiratory and cardiac motion. A MRI linear accelerator (MRI-Linac) could solve the problems of motion tracking and compensation using real-time image guidance. In this study, the authors quantified target motion ranges on cardiac magnetic resonance imaging (MRI) and analyzed the dosimetric benefits of margin reduction assuming real-time motion compensation was applied. For the imaging study, six human subjects underwent real-time cardiac MRI under free breathing. The target motion was analyzed retrospectively using a template matching algorithm. The planning study was conducted on a CT of an AFib patient with a centrally located esophagus undergoing catheter ablation, representing an ideal case for cardiac radiosurgery. The target definition was similar to the ablation lesions at the PVA created during catheter treatment. Safety margins of 0 mm (perfect tracking) to 8 mm (untracked respiratory motion) were added to the target, defining the planning target volume (PTV). For each margin, a 30 Gy single fraction IMRT plan was generated. Additionally, the influence of 1 and 3 T magnetic fields on the treatment beam delivery was simulated using Monte Carlo calculations to determine the dosimetric impact of MRI guidance for two different Linac positions. Real-time cardiac MRI showed mean respiratory target motion of 10.2 mm (superior-inferior), 2.4 mm (anterior-posterior), and 2 mm (left-right). The planning study showed that increasing safety margins to encompass untracked respiratory motion leads to overlapping structures even in the ideal scenario, compromising

  19. Toward a web-based real-time radiation treatment planning system in a cloud computing environment

    International Nuclear Information System (INIS)

    Na, Yong Hum; Kapp, Daniel S; Xing, Lei; Suh, Tae-Suk

    2013-01-01

    To exploit the potential dosimetric advantages of intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), an in-depth approach is required to provide efficient computing methods. This needs to incorporate clinically related organ specific constraints, Monte Carlo (MC) dose calculations, and large-scale plan optimization. This paper describes our first steps toward a web-based real-time radiation treatment planning system in a cloud computing environment (CCE). The Amazon Elastic Compute Cloud (EC2) with a master node (named m2.xlarge containing 17.1 GB of memory, two virtual cores with 3.25 EC2 Compute Units each, 420 GB of instance storage, 64-bit platform) is used as the backbone of cloud computing for dose calculation and plan optimization. The master node is able to scale the workers on an ‘on-demand’ basis. MC dose calculation is employed to generate accurate beamlet dose kernels by parallel tasks. The intensity modulation optimization uses total-variation regularization (TVR) and generates piecewise constant fluence maps for each initial beam direction in a distributed manner over the CCE. The optimized fluence maps are segmented into deliverable apertures. The shape of each aperture is iteratively rectified to be a sequence of arcs using the manufacture’s constraints. The output plan file from the EC2 is sent to the simple storage service. Three de-identified clinical cancer treatment plans have been studied for evaluating the performance of the new planning platform with 6 MV flattening filter free beams (40 × 40 cm 2 ) from the Varian TrueBeam TM STx linear accelerator. A CCE leads to speed-ups of up to 14-fold for both dose kernel calculations and plan optimizations in the head and neck, lung, and prostate cancer cases considered in this study. The proposed system relies on a CCE that is able to provide an infrastructure for parallel and distributed computing. The resultant plans from the cloud computing are

  20. Toward a web-based real-time radiation treatment planning system in a cloud computing environment.

    Science.gov (United States)

    Na, Yong Hum; Suh, Tae-Suk; Kapp, Daniel S; Xing, Lei

    2013-09-21

    To exploit the potential dosimetric advantages of intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), an in-depth approach is required to provide efficient computing methods. This needs to incorporate clinically related organ specific constraints, Monte Carlo (MC) dose calculations, and large-scale plan optimization. This paper describes our first steps toward a web-based real-time radiation treatment planning system in a cloud computing environment (CCE). The Amazon Elastic Compute Cloud (EC2) with a master node (named m2.xlarge containing 17.1 GB of memory, two virtual cores with 3.25 EC2 Compute Units each, 420 GB of instance storage, 64-bit platform) is used as the backbone of cloud computing for dose calculation and plan optimization. The master node is able to scale the workers on an 'on-demand' basis. MC dose calculation is employed to generate accurate beamlet dose kernels by parallel tasks. The intensity modulation optimization uses total-variation regularization (TVR) and generates piecewise constant fluence maps for each initial beam direction in a distributed manner over the CCE. The optimized fluence maps are segmented into deliverable apertures. The shape of each aperture is iteratively rectified to be a sequence of arcs using the manufacture's constraints. The output plan file from the EC2 is sent to the simple storage service. Three de-identified clinical cancer treatment plans have been studied for evaluating the performance of the new planning platform with 6 MV flattening filter free beams (40 × 40 cm(2)) from the Varian TrueBeam(TM) STx linear accelerator. A CCE leads to speed-ups of up to 14-fold for both dose kernel calculations and plan optimizations in the head and neck, lung, and prostate cancer cases considered in this study. The proposed system relies on a CCE that is able to provide an infrastructure for parallel and distributed computing. The resultant plans from the cloud computing are

  1. A Simulation Study for Radiation Treatment Planning Based on the Atomic Physics of the Proton-Boron Fusion Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sunmi; Yoon, Do-Kun; Shin, Han-Back; Jung, Joo-Young; Kim, Moo-Sub; Kim, Kyeong-Hyeon; Jang, Hong-Seok; Suh, Tae Suk [the Catholic University of Korea, Seoul (Korea, Republic of)

    2017-03-15

    The purpose of this research is to demonstrate, based on a Monte Carlo simulation code, the procedure of radiation treatment planning for proton-boron fusion therapy (PBFT). A discrete proton beam (60 - 120 MeV) relevant to the Bragg peak was simulated using a Monte Carlo particle extended (MCNPX, Ver. 2.6.0, National Laboratory, Los Alamos NM, USA) simulation code. After computed tomography (CT) scanning of a virtual water phantom including air cavities, the acquired CT images were converted using the simulation source code. We set the boron uptake regions (BURs) in the simulated water phantom to achieve the proton-boron fusion reaction. Proton sources irradiated the BUR, in the phantom. The acquired dose maps were overlapped with the original CT image of the phantom to analyze the dose volume histogram (DVH). We successfully confirmed amplifications of the proton doses (average: 130%) at the target regions. From the DVH result for each simulation, we acquired a relatively accurate dose map for the treatment. A simulation was conducted to characterize the dose distribution and verify the feasibility of proton boron fusion therapy (PBFT). We observed a variation in proton range and developed a tumor targeting technique for treatment that was more accurate and powerful than both conventional proton therapy and boron-neutron capture therapy.

  2. A simulation study for radiation treatment planning based on the atomic physics of the proton-boron fusion reaction

    Science.gov (United States)

    Kim, Sunmi; Yoon, Do-Kun; Shin, Han-Back; Jung, Joo-Young; Kim, Moo-Sub; Kim, Kyeong-Hyeon; Jang, Hong-Seok; Suh, Tae Suk

    2017-03-01

    The purpose of this research is to demonstrate, based on a Monte Carlo simulation code, the procedure of radiation treatment planning for proton-boron fusion therapy (PBFT). A discrete proton beam (60 - 120 MeV) relevant to the Bragg peak was simulated using a Monte Carlo n-particle extended (MCNPX, Ver. 2.6.0, National Laboratory, Los Alamos NM, USA) simulation code. After computed tomography (CT) scanning of a virtual water phantom including air cavities, the acquired CT images were converted using the simulation source code. We set the boron uptake regions (BURs) in the simulated water phantom to achieve the proton-boron fusion reaction. Proton sources irradiated the BUR, in the phantom. The acquired dose maps were overlapped with the original CT image of the phantom to analyze the dose volume histogram (DVH). We successfully confirmed amplifications of the proton doses (average: 130%) at the target regions. From the DVH result for each simulation, we acquired a relatively accurate dose map for the treatment. A simulation was conducted to characterize the dose distribution and verify the feasibility of proton-boron fusion therapy (PBFT). We observed a variation in proton range and developed a tumor-targeting technique for treatment that was more accurate and powerful than both conventional proton therapy and boron-neutron capture therapy.

  3. MO-D-BRB-01: Pediatric Treatment Planning I: Overview of Planning Strategies and Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Olch, A. [Childrens Hospital of LA (United States)

    2015-06-15

    Most Medical Physicists working in radiotherapy departments see few pediatric patients. This is because, fortunately, children get cancer at a rate nearly 100 times lower than adults. Children have not smoked, abused alcohol, or been exposed to environmental carcinogens for decades, and of course, have not fallen victim to the aging process. Children get very different cancers than adults. Breast or prostate cancers, typical in adults, are rarely seen in children but instead a variety of tumors occur in children that are rarely seen in adults; examples are germinomas, ependymomas and primitive neuroectodermal tumors, which require treatment of the child’s brain or neuroblastoma, requiring treatment in the abdomen. The treatment of children with cancer using radiation therapy is one of the most challenging planning and delivery problems facing the physicist. This is because bones, brain, breast tissue, and other organs are more sensitive to radiation in children than in adults. Because most therapy departments treat mostly adults, when the rare 8 year-old patient comes to the department for treatment, the physicist may not understand the clinical issues of his disease which drive the planning and delivery decisions. Additionally, children are more prone than adults to developing secondary cancers after radiation. For bilateral retinoblastoma for example, an irradiated child has a 40% chance of developing a second cancer by age 50. The dosimetric tradeoffs made during the planning process are complex and require careful consideration for children treated with radiotherapy. In the first presentation, an overview of childhood cancers and their corresponding treatment techniques will be given. These can be some of the most complex treatments that are delivered in the radiation therapy department. These cancers include leukemia treated with total body irradiation, medulloblastoma, treated with craniospinal irradiation plus a conformal boost to the posterior fossa

  4. MO-D-BRB-01: Pediatric Treatment Planning I: Overview of Planning Strategies and Challenges

    International Nuclear Information System (INIS)

    Olch, A.

    2015-01-01

    Most Medical Physicists working in radiotherapy departments see few pediatric patients. This is because, fortunately, children get cancer at a rate nearly 100 times lower than adults. Children have not smoked, abused alcohol, or been exposed to environmental carcinogens for decades, and of course, have not fallen victim to the aging process. Children get very different cancers than adults. Breast or prostate cancers, typical in adults, are rarely seen in children but instead a variety of tumors occur in children that are rarely seen in adults; examples are germinomas, ependymomas and primitive neuroectodermal tumors, which require treatment of the child’s brain or neuroblastoma, requiring treatment in the abdomen. The treatment of children with cancer using radiation therapy is one of the most challenging planning and delivery problems facing the physicist. This is because bones, brain, breast tissue, and other organs are more sensitive to radiation in children than in adults. Because most therapy departments treat mostly adults, when the rare 8 year-old patient comes to the department for treatment, the physicist may not understand the clinical issues of his disease which drive the planning and delivery decisions. Additionally, children are more prone than adults to developing secondary cancers after radiation. For bilateral retinoblastoma for example, an irradiated child has a 40% chance of developing a second cancer by age 50. The dosimetric tradeoffs made during the planning process are complex and require careful consideration for children treated with radiotherapy. In the first presentation, an overview of childhood cancers and their corresponding treatment techniques will be given. These can be some of the most complex treatments that are delivered in the radiation therapy department. These cancers include leukemia treated with total body irradiation, medulloblastoma, treated with craniospinal irradiation plus a conformal boost to the posterior fossa

  5. A Monte-Carlo study to assess the effect of 1.5 T magnetic fields on the overall robustness of pencil-beam scanning proton radiotherapy plans for prostate cancer

    Science.gov (United States)

    Kurz, Christopher; Landry, Guillaume; Resch, Andreas F.; Dedes, George; Kamp, Florian; Ganswindt, Ute; Belka, Claus; Raaymakers, Bas W.; Parodi, Katia

    2017-11-01

    Combining magnetic-resonance imaging (MRI) and proton therapy (PT) using pencil-beam scanning (PBS) may improve image-guided radiotherapy. We aimed at assessing the impact of a magnetic field on PBS-PT plan quality and robustness. Specifically, the robustness against anatomical changes and positioning errors in an MRI-guided scenario with a 30 cm radius 1.5 T magnetic field was studied for prostate PT. Five prostate cancer patients with three consecutive CT images (CT1-3) were considered. Single-field uniform dose PBS-PT plans were generated on the segmented CT1 with Monte-Carlo-based treatment planning software for inverse optimization. Plans were optimized at 90° gantry angle without B-field (no B), with  ±1.5 T B-field (B and minus B), as well as at 81° gantry angle and  +1.5 T (B G81). Plans were re-calculated on aligned CT2 and CT3 to study the impact of anatomical changes. Dose distributions were compared in terms of changes in DVH parameters, proton range and gamma-index pass-rates. To assess the impact of positioning errors, DVH parameters were compared for  ±5 mm CT1 patient shifts in anterior-posterior (AP) and left-right (LR) direction. Proton beam deflection considerably reduced robustness against inter-fractional changes for the B scenario. Range agreement, gamma-index pass-rates and PTV V95% were significantly lower compared to no B. Improved robustness was obtained for minus B and B G81, the latter showing only minor differences to no B. The magnetic field introduced slight dosimetric changes under LR shifts. The impact of AP shifts was considerably larger, and equivalent for scenarios with and without B-field. Results suggest that robustness equivalent to PT without magnetic field can be achieved by adaptation of the treatment parameters, such as B-field orientation (minus B) with respect to the patient and/or gantry angle (B G81). MRI-guided PT for prostate cancer might thus be implemented without compromising robustness

  6. MO-C-BRF-01: Pediatric Treatment Planning I: Overview of Planning Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Olch, A [Childrens Hospital of LA, Los Angeles, CA (United States); Hua, C [St. Jude Childrens Research Hospital, Memphis, TN (United States)

    2014-06-15

    Most Medical Physicists working in radiotherapy departments see few pediatric patients. This is because, fortunately, children get cancer at a rate nearly 100 times lower than adults. Children have not smoked, abused alcohol, or been exposed to environmental carcinogens for decades, and of course, have not fallen victim to the aging process. Children get very different cancers than adults. Breast or prostate cancers, typical in adults, are rarely seen in children but instead a variety of tumors occur in children that are rarely seen in adults; examples are germinomas, ependymomas and primitive neuroectodermal tumors, which require treatment of the child's brain or neuroblastoma, requiring treatment in the abdomen. The treatment of children with cancer using radiation therapy is one of the most challenging planning and delivery problems facing the physicist. This is because bones, brain, breast tissue, and other organs are more sensitive to radiation in children than in adults. Because most therapy departments treat mostly adults, when the rare 8 year-old patient comes to the department for treatment, the physicist may not understand the clinical issues of his disease which drive the planning and delivery decisions. Additionally, children are more prone than adults to developing secondary cancers after radiation. This fact has important implications for the choice of delivery techniques, especially when considering IMRT. For bilateral retinoblastoma for example, an irradiated child has a 50% chance of developing a second cancer by age 50. In the first presentation, an overview of childhood cancers and their corresponding treatment techniques will be given. These can be some of the most complex treatments that are delivered in the radiation therapy department. These cancers include leukemia treated with total body irradiation, medulloblastoma, treated with craniospinal irradiation plus a conformal boost to the posterior fossa, neuroblastoma, requiring focal

  7. Estimation of tumour dose enhancement due to gold nanoparticles during typical radiation treatments: a preliminary Monte Carlo study

    International Nuclear Information System (INIS)

    Cho, S H

    2005-01-01

    A recent mice study demonstrated that gold nanoparticles could be safely administered and used to enhance the tumour dose during radiation therapy. The use of gold nanoparticles seems more promising than earlier methods because of the high atomic number of gold and because nanoparticles can more easily penetrate the tumour vasculature. However, to date, possible dose enhancement due to the use of gold nanoparticles has not been well quantified, especially for common radiation treatment situations. Therefore, the current preliminary study estimated this dose enhancement by Monte Carlo calculations for several phantom test cases representing radiation treatments with the following modalities: 140 kVp x-rays, 4 and 6 MV photon beams, and 192 Ir gamma rays. The current study considered three levels of gold concentration within the tumour, two of which are based on the aforementioned mice study, and assumed either no gold or a single gold concentration level outside the tumour. The dose enhancement over the tumour volume considered for the 140 kVp x-ray case can be at least a factor of 2 at an achievable gold concentration of 7 mg Au/g tumour assuming no gold outside the tumour. The tumour dose enhancement for the cases involving the 4 and 6 MV photon beams based on the same assumption ranged from about 1% to 7%, depending on the amount of gold within the tumour and photon beam qualities. For the 192 Ir cases, the dose enhancement within the tumour region ranged from 5% to 31%, depending on radial distance and gold concentration level within the tumour. For the 7 mg Au/g tumour cases, the loading of gold into surrounding normal tissue at 2 mg Au/g resulted in an increase in the normal tissue dose, up to 30%, negligible, and about 2% for the 140 kVp x-rays, 6 MV photon beam, and 192 Ir gamma rays, respectively, while the magnitude of dose enhancement within the tumour was essentially unchanged. (note)

  8. Sci—Thur PM: Planning and Delivery — 06: Real-Time Interactive Treatment Planning

    International Nuclear Information System (INIS)

    Matthews, Q; Mestrovic, A; Otto, K

    2014-01-01

    Purpose: To describe and evaluate a novel system for generalized Real-Time Interactive Planning (RTIP) applied to head and neck (H and N) VMAT. Methods: The clinician interactively manipulates dose distributions using DVHs, isodoses, or rate of dose fall-off, which may be subjected to user-defined constraints. Dose is calculated using a fast Achievable Dose Estimate (ADE) algorithm, which simulates the limits of what can be achieved during treatment. After each manipulation contributing fluence elements are modified and the dose distribution updates in effectively real-time. For H and N VMAT planning, structure sets for 11 patients were imported into RTIP. Each dose distribution was interactively modified to minimize OAR dose while constraining target DVHs. The resulting RTIP DVHs were transferred to the Eclipse™ VMAT optimizer, and conventional VMAT optimization was performed. Results: Dose calculation and update times for the ADE algorithm ranged from 2.4 to 22.6 milliseconds, thus facilitating effectively real-time manipulation of dose distributions. For each of the 11 H and N VMAT cases, the RTIP process took ∼2–10 minutes. All RTIP plans exhibited acceptable PTV coverage, mean dose, and max dose. 10 of 11 RTIP plans achieved substantially improved sparing of one or more OARs without compromising dose to targets or other OARs. Importantly, 10 of the 11 RTIP plans required only one or two post-RTIP optimizations. Conclusions: RTIP is a novel system for manipulating and updating achievable dose distributions in real-time. H and N VMAT plans generated using RTIP demonstrate improved OAR sparing and planning efficiency. Disclosures: One author has a commercial interest in the presented materials

  9. A practical approach to assess clinical planning tradeoffs in the design of individualized IMRT treatment plans

    International Nuclear Information System (INIS)

    Monshouwer, Rene; Hoffmann, Aswin L.; Kunze-Busch, Martina; Bussink, Johan; Kaanders, Johannes H.A.M.; Huizenga, Henk

    2010-01-01

    Background and purpose: To investigate the tradeoffs between organ at risk sparing and tumour coverage for IMRT treatment of lung tumours, and to develop a tool for clinical use to graphically represent these tradeoffs. Material and methods: For 5 patients with inoperable non-small cell lung cancer (NSCLC) different IMRT plans were generated using a standard TPS. The plans were automatically generated for a range of IMRT settings (weights and dose levels of the objective functions) and were systematically evaluated, focusing on the tradeoffs between organ at risk (OAR) dose and target coverage. A method to analyze and visualize planning tradeoffs was developed and evaluated. Results: Lung and oesophagus were identified as the critical organs at risk for NSCLC, the sparing of which strongly influences PTV coverage. Systematically analyzing the tradeoffs between these organs revealed that the sparing of these organs was approximately linearly related to PTV coverage parameters. Using this property, a tool was developed to graphically present the tradeoffs between the sparing of these organs at risk and the PTV coverage. The tool is an effective method to visualize the tradeoffs. Conclusions: A tool was developed to assist IMRT plan design and selection. The clear presentation of the tradeoffs between OAR dose and coverage facilitates the optimization process and offers additional information to the clinician for a patient specific choice of the optimal IMRT plan.

  10. Quantification of the influence of the choice of the algorithm and planning system on the calculation of a treatment plan

    International Nuclear Information System (INIS)

    Moral, F. del; Ramos, A.; Salgado, M.; Andrade, B; Munoz, V.

    2010-01-01

    In this work an analysis of the influence of the choice of the algorithm or planning system, on the calculus of the same treatment plan is introduced. For this purpose specific software has been developed for comparing plans of a series of IMRT cases of prostate and head and neck cancer calculated using the convolution, superposition and fast superposition algorithms implemented in the XiO 4.40 planning system (CMS). It has also been used for the comparison of the same treatment plan for lung pathology calculated in XiO with the mentioned algorithms, and calculated in the Plan 4.1 planning system (Brainlab) using its pencil beam algorithm. Differences in dose among the treatment plans have been quantified using a set of metrics. The recommendation for the dosimetrist of a careful choice of the algorithm has been numerically confirmed. (Author).

  11. Incorporating model parameter uncertainty into inverse treatment planning

    International Nuclear Information System (INIS)

    Lian Jun; Xing Lei

    2004-01-01

    Radiobiological treatment planning depends not only on the accuracy of the models describing the dose-response relation of different tumors and normal tissues but also on the accuracy of tissue specific radiobiological parameters in these models. Whereas the general formalism remains the same, different sets of model parameters lead to different solutions and thus critically determine the final plan. Here we describe an inverse planning formalism with inclusion of model parameter uncertainties. This is made possible by using a statistical analysis-based frameset developed by our group. In this formalism, the uncertainties of model parameters, such as the parameter a that describes tissue-specific effect in the equivalent uniform dose (EUD) model, are expressed by probability density function and are included in the dose optimization process. We found that the final solution strongly depends on distribution functions of the model parameters. Considering that currently available models for computing biological effects of radiation are simplistic, and the clinical data used to derive the models are sparse and of questionable quality, the proposed technique provides us with an effective tool to minimize the effect caused by the uncertainties in a statistical sense. With the incorporation of the uncertainties, the technique has potential for us to maximally utilize the available radiobiology knowledge for better IMRT treatment

  12. On the quality of treatment planning systems in radiation therapy.

    Science.gov (United States)

    Panten, T; Höss, A; Bohsung, J; Becker, G; Sroka-Pérez, G

    1998-10-01

    To assist in the design of quality assurance activities of 3D treatment planning systems (TPSs), a postal survey has been carried out, addressing TPS users on quality characteristics and their relative importance in clinical routine planning. The approach as described in ISO/IEC 9126 has been used to analyze TPS quality. Both TPS quality characteristics and how these may be used to establish a quality model are included. A questionnaire on ranking of these TPS quality characteristics has been sent out to the German DEGRO members in February 1997. By the end of July 1997, 90 individual assessments (of 45 physicists, 35 physicians, and 10 radiographers) had been collected. On an importance scale from 1 (very important) to 6 (unimportant), weight factors of 1.71 (portability), 2.84 (maintainability), 3.18 (efficiency), 3.85 (usability), 4.52 (functionality) and 4.90 (reliability) have been determined from the data. From user satisfaction data also obtained from the questionnaire responses, baseline quality indices could be established from the quality model for the RTPs Cadplan, TMS Helax, and Voxelplan. The responses highlight the need for TPS quality assurance at the same time along the lines of safety-related, research-oriented, and interactive end-user software systems in radiotherapy treatment planning. Quality assurance activities must take this into account. Their effect can be monitored by using quality indices as derivable from the established quality model.

  13. Treatment planning systems dosimetry auditing project in Portugal.

    Science.gov (United States)

    Lopes, M C; Cavaco, A; Jacob, K; Madureira, L; Germano, S; Faustino, S; Lencart, J; Trindade, M; Vale, J; Batel, V; Sousa, M; Bernardo, A; Brás, S; Macedo, S; Pimparel, D; Ponte, F; Diaz, E; Martins, A; Pinheiro, A; Marques, F; Batista, C; Silva, L; Rodrigues, M; Carita, L; Gershkevitsh, E; Izewska, J

    2014-02-01

    The Medical Physics Division of the Portuguese Physics Society (DFM_SPF) in collaboration with the IAEA, carried out a national auditing project in radiotherapy, between September 2011 and April 2012. The objective of this audit was to ensure the optimal usage of treatment planning systems. The national results are presented in this paper. The audit methodology simulated all steps of external beam radiotherapy workflow, from image acquisition to treatment planning and dose delivery. A thorax CIRS phantom lend by IAEA was used in 8 planning test-cases for photon beams corresponding to 15 measuring points (33 point dose results, including individual fields in multi-field test cases and 5 sum results) in different phantom materials covering a set of typical clinical delivery techniques in 3D Conformal Radiotherapy. All 24 radiotherapy centers in Portugal have participated. 50 photon beams with energies 4-18 MV have been audited using 25 linear accelerators and 32 calculation algorithms. In general a very good consistency was observed for the same type of algorithm in all centres and for each beam quality. The overall results confirmed that the national status of TPS calculations and dose delivery for 3D conformal radiotherapy is generally acceptable with no major causes for concern. This project contributed to the strengthening of the cooperation between the centres and professionals, paving the way to further national collaborations. Copyright © 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Automation of radiation treatment planning : Evaluation of head and neck cancer patient plans created by the Pinnacle3 scripting and Auto-Planning functions.

    Science.gov (United States)

    Speer, Stefan; Klein, Andreas; Kober, Lukas; Weiss, Alexander; Yohannes, Indra; Bert, Christoph

    2017-08-01

    Intensity-modulated radiotherapy (IMRT) techniques are now standard practice. IMRT or volumetric-modulated arc therapy (VMAT) allow treatment of the tumor while simultaneously sparing organs at risk. Nevertheless, treatment plan quality still depends on the physicist's individual skills, experiences, and personal preferences. It would therefore be advantageous to automate the planning process. This possibility is offered by the Pinnacle 3 treatment planning system (Philips Healthcare, Hamburg, Germany) via its scripting language or Auto-Planning (AP) module. AP module results were compared to in-house scripts and manually optimized treatment plans for standard head and neck cancer plans. Multiple treatment parameters were scored to judge plan quality (100 points = optimum plan). Patients were initially planned manually by different physicists and re-planned using scripts or AP. Script-based head and neck plans achieved a mean of 67.0 points and were, on average, superior to manually created (59.1 points) and AP plans (62.3 points). Moreover, they are characterized by reproducibility and lower standard deviation of treatment parameters. Even less experienced staff are able to create at least a good starting point for further optimization in a short time. However, for particular plans, experienced planners perform even better than scripts or AP. Experienced-user input is needed when setting up scripts or AP templates for the first time. Moreover, some minor drawbacks exist, such as the increase of monitor units (+35.5% for scripted plans). On average, automatically created plans are superior to manually created treatment plans. For particular plans, experienced physicists were able to perform better than scripts or AP; thus, the benefit is greatest when time is short or staff inexperienced.

  15. Strategies for CT tissue segmentation for Monte Carlo calculations in nuclear medicine dosimetry

    DEFF Research Database (Denmark)

    Braad, Poul-Erik; Andersen, Thomas; Hansen, Søren Baarsgaard

    2016-01-01

    Purpose: CT images are used for patient specific Monte Carlo treatment planning in radionuclide therapy. The authors investigated the impact of tissue classification, CT image segmentation, and CT errors on Monte Carlo calculated absorbed dose estimates in nuclear medicine. Methods: CT errors...... calibration of the CT number-to-density conversion ramp. Tissue segmentation by a 13-tissue CT conversion ramp, calibrated by a stoichiometric method, resulted in low (isotopes. Conclusions: A calibrated CT scanner specific conversion ramp is required for accurate...

  16. Monte Carlo simulation of the Tomotherapy treatment unit in the static mode using MC HAMMER, a Monte Carlo tool dedicated to Tomotherapy

    International Nuclear Information System (INIS)

    Sterpin, E; Tomsej, M; Cravens, B; Salvat, F; Ruchala, K; Olivera, G H; Vynckier, S

    2007-01-01

    Helical tomotherapy (HT) is designed to deliver highly modulated IMRT treatments. The concept of HT provides new challenges in MC simulation, because simultaneous movement of the gantry, the couch and the multi-leaf collimator (MLC) must be simulated accurately. However, before accounting for gantry, couch movement and multileaf collimator configurations, high accuracy must be achieved while simulating open static fields (1 x 40, 2.5 x 40 and 5 x 40 cm 2 ). This is performed using MC HAMMER, which is a graphical user interface allowing MC simulation using PENELOPE for various configurations of HT. Since the geometry of the different elements and materials involved in the beam generation are precisely known and defined, the only parameters that need to be tuned on are therefore electron source spot size and electron energy. Beyond the build up region, good agreement (2%/1mm) is achieved for all the field sizes between measurements (ion chamber) and simulations with an electron source energy set to 5.5 MeV. The electron source spot size is modelled as a gaussian distribution with full width half maximum equal to 1.4 mm. This value was chosen to match measured and calculated penumbras in the longitudinal direction

  17. Patient selection and treatment planning for implant restorations.

    Science.gov (United States)

    Bryington, Matthew; De Kok, Ingeborg J; Thalji, Ghadeer; Cooper, Lyndon F

    2014-01-01

    Dental implants are an indispensible tool for the restoration of missing teeth. Their use has elevated the practice of dentistry by improving both our technical ability to rehabilitate patients and general quality of life. To routinely achieve the associated high expectations, diligent attention to details must be observed and addressed from the outset. Of central concern is the attainment of osseointegration and the location of implants to ideally support the intended restoration. The pivotal point in treatment planning for dental implants occurs when the location of bone is viewed radiographically in the context of the planned prosthesis. This most often requires diagnostic waxing or tooth arrangement using mounted diagnostic casts. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. 3-Dimentional radiotherapy versus conventional treatment plans for gastric cancer

    Directory of Open Access Journals (Sweden)

    Aghili M

    2010-11-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: The current standard of adjuvant management for gastric cancer after curative resection based on the results of intergroup 0116 is concurrent chemoradiation. Current guidelines for designing these challenging fields still include two-dimensional simulation with simple AP-PA parallel opposed design. However, the implementation of radiotherapy (RT remains a concern. Our objective was to compare three-dimensional (3D techniques to the more commonly used AP-PA technique."n"nMethods: A total of 24 patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiation with simple AP-PA technique, using Cobalt-60. Total radiation dose was 50.4Gy. Landmark-based fields were simulated to assess PTV coverage. For each patient, three additional radiotherapy treatment plans were generated using three-dimensional (3D technique. The four treatment plans were then compared for target volume coverage and dose to normal tissues (liver, spinal cord, kidneys using dose volume histogram (DVH analysis."n"nResults: The three-dimensional planning techniques provided 10% superior PTV coverage compared to conventional AP-PA fields (p<0.001. Comparative DVHs for the right kidney, left kidney

  19. Plutonium Finishing Plan (PFP) Treatment and Storage Unit Interim Status Closure Plan

    International Nuclear Information System (INIS)

    PRIGNANO, A.L.

    2000-01-01

    This document describes the planned activities and performance standards for closing the Plutonium Finishing Plant (PFP) Treatment and Storage Unit. The PFP Treatment and Storage Unit is located within the 234-52 Building in the 200 West Area of the Hanford Facility. Although this document is prepared based upon Title 40 Code of Federal Regulations (CFR), Part 265, Subpart G requirements, closure of the unit will comply with Washington Administrative Code (WAC) 173-303-610 regulations pursuant to Section 5.3 of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Action Plan (Ecology et al. 1996). Because the PFP Treatment and Storage Unit manages transuranic mixed (TRUM) waste, there are many controls placed on management of the waste. Based on the many controls placed on management of TRUM waste, releases of TRUM waste are not anticipated to occur in the PFP Treatment and Storage Unit. Because the intention is to clean close the PFP Treatment and Storage Unit, postclosure activities are not applicable to this closure plan. To clean close the unit, it will be demonstrated that dangerous waste has not been left onsite at levels above the closure performance standard for removal and decontamination. If it is determined that clean closure is not possible or is environmentally impractical, the closure plan will be modified to address required postclosure activities. The PFP Treatment and Storage Unit will be operated to immobilize and/or repackage plutonium-bearing waste in a glovebox process. The waste to be processed is in a solid physical state (chunks and coarse powder) and will be sealed into and out of the glovebox in closed containers. The containers of immobilized waste will be stored in the glovebox and in additional permitted storage locations at PFP. The waste will be managed to minimize the potential for spills outside the glovebox, and to preclude spills from reaching soil. Containment surfaces will be maintained to ensure

  20. A new plan-scoring method using normal tissue complication probability for personalized treatment plan decisions in prostate cancer

    Science.gov (United States)

    Kim, Kwang Hyeon; Lee, Suk; Shim, Jang Bo; Yang, Dae Sik; Yoon, Won Sup; Park, Young Je; Kim, Chul Yong; Cao, Yuan Jie; Chang, Kyung Hwan

    2018-01-01

    The aim of this study was to derive a new plan-scoring index using normal tissue complication probabilities to verify different plans in the selection of personalized treatment. Plans for 12 patients treated with tomotherapy were used to compare scoring for ranking. Dosimetric and biological indexes were analyzed for the plans for a clearly distinguishable group ( n = 7) and a similar group ( n = 12), using treatment plan verification software that we developed. The quality factor ( QF) of our support software for treatment decisions was consistent with the final treatment plan for the clearly distinguishable group (average QF = 1.202, 100% match rate, n = 7) and the similar group (average QF = 1.058, 33% match rate, n = 12). Therefore, we propose a normal tissue complication probability (NTCP) based on the plan scoring index for verification of different plans for personalized treatment-plan selection. Scoring using the new QF showed a 100% match rate (average NTCP QF = 1.0420). The NTCP-based new QF scoring method was adequate for obtaining biological verification quality and organ risk saving using the treatment-planning decision-support software we developed for prostate cancer.

  1. Suitability of point kernel dose calculation techniques in brachytherapy treatment planning

    Directory of Open Access Journals (Sweden)

    Lakshminarayanan Thilagam

    2010-01-01

    Full Text Available Brachytherapy treatment planning system (TPS is necessary to estimate the dose to target volume and organ at risk (OAR. TPS is always recommended to account for the effect of tissue, applicator and shielding material heterogeneities exist in applicators. However, most brachytherapy TPS software packages estimate the absorbed dose at a point, taking care of only the contributions of individual sources and the source distribution, neglecting the dose perturbations arising from the applicator design and construction. There are some degrees of uncertainties in dose rate estimations under realistic clinical conditions. In this regard, an attempt is made to explore the suitability of point kernels for brachytherapy dose rate calculations and develop new interactive brachytherapy package, named as BrachyTPS, to suit the clinical conditions. BrachyTPS is an interactive point kernel code package developed to perform independent dose rate calculations by taking into account the effect of these heterogeneities, using two regions build up factors, proposed by Kalos. The primary aim of this study is to validate the developed point kernel code package integrated with treatment planning computational systems against the Monte Carlo (MC results. In the present work, three brachytherapy applicators commonly used in the treatment of uterine cervical carcinoma, namely (i Board of Radiation Isotope and Technology (BRIT low dose rate (LDR applicator and (ii Fletcher Green type LDR applicator (iii Fletcher Williamson high dose rate (HDR applicator, are studied to test the accuracy of the software. Dose rates computed using the developed code are compared with the relevant results of the MC simulations. Further, attempts are also made to study the dose rate distribution around the commercially available shielded vaginal applicator set (Nucletron. The percentage deviations of BrachyTPS computed dose rate values from the MC results are observed to be within plus/minus 5

  2. Comparison of step and shoot IMRT treatment plans generated by three inverse treatment planning systems; Comparacion de tratamientos de IMRT estatica generados por tres sistemas de planificacion inversa

    Energy Technology Data Exchange (ETDEWEB)

    Perez Moreno, J. M.; Zucca Aparicio, D.; Fernandez leton, P.; Garcia Ruiz-Zorrilla, J.; Minambres Moro, A.

    2011-07-01

    One of the most important issues of intensity modulated radiation therapy (IMRT) treatments using the step-and-shoot technique is the number of segments and monitor units (MU) for treatment delivery. These parameters depend heavily on the inverse optimization module of the treatment planning system (TPS) used. Three commercial treatment planning systems: CMS XiO, iPlan and Prowess Panther have been evaluated. With each of them we have generated a treatment plan for the same group of patients, corresponding to clinical cases. Dosimetric results, MU calculated and number of segments were compared. Prowess treatment planning system generates plans with a number of segments significantly lower than other systems, while MU are less than a half. It implies important reductions in leakage radiation and delivery time. Degradation in the final dose calculation of dose is very small, because it directly optimizes positions of multileaf collimator (MLC). (Author) 13 refs.

  3. Conformal Radiotherapy: Physics, Treatment Planning and Verification. Proceedings book

    Energy Technology Data Exchange (ETDEWEB)

    De Wagter, C. [ed.

    1995-12-01

    The goal of conformal radiotherapy is to establish radiation dose distributions that conform tightly to the target volume in view of limiting radiation to normal tissues. Conformal radiotherapy significantly improves both local control and palliation and thus contributes to increase survival and to improve the quality of life. The subjects covered by the symposium include : (1) conformal radiotherapy and multi-leaf collimation; (2) three dimensional imaging; (3) treatment simulation, planning and optimization; (4) quality assurance; and (5) dosimetry. The book of proceedings contains the abstracts of the invited lectures, papers and poster presentations as well as the full papers of these contributions.

  4. Conformal Radiotherapy: Physics, Treatment Planning and Verification. Proceedings book

    International Nuclear Information System (INIS)

    De Wagter, C.

    1995-12-01

    The goal of conformal radiotherapy is to establish radiation dose distributions that conform tightly to the target volume in view of limiting radiation to normal tissues. Conformal radiotherapy significantly improves both local control and palliation and thus contributes to increase survival and to improve the quality of life. The subjects covered by the symposium include : (1) conformal radiotherapy and multi-leaf collimation; (2) three dimensional imaging; (3) treatment simulation, planning and optimization; (4) quality assurance; and (5) dosimetry. The book of proceedings contains the abstracts of the invited lectures, papers and poster presentations as well as the full papers of these contributions

  5. 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

  6. Nevada Test Site, site treatment plan 1999 annual update

    International Nuclear Information System (INIS)

    1999-03-01

    A Site Treatment Plan (STP) is required for facilities at which the US Department of Energy Nevada Operations Office (DOE/NV) generates or stores mixed waste (MW), defined by the Federal Facility Compliance Act (FFC Act) as waste containing both a hazardous waste subject to the Resource Conservation and Recovery Act (RCRA) and a radioactive material subject to the Atomic Energy Act. This STP was written to identify specific treatment facilities for treating DOE/NV generated MW and provides proposed implementation schedules. This STP was approved by the Nevada Division of Environmental Protection (NDEP) and provided the basis for the negotiation and issuance of the FFC Act Consent Order (CO) dated March 6, 1996, and revised June 15, 1998. The FFC Act CO sets forth stringent regulatory requirements to comply with the implementation of the STP

  7. Multiobjective approach in plans for treatment of cancer by radiotherapy

    Directory of Open Access Journals (Sweden)

    Thalita Monteiro Obal

    2013-08-01

    Full Text Available Nowadays the technique of radiotherapy has been one of the main alternatives for the treatment of several types of cancer today. With technological development, especially in the case of 3D conformal radiotherapy, applications involving mathematical techniques and algorithms have been proposed to help the development a good treatment plan. This paper aims at present a model for multiobjective linear programming problem of dose intensity. The focus of the model is to determine the best dose distribution of radiation field, so that the dose delivered to the tumor to be prescribed and that affects the minimum the noble and healthy tissues. A test case of prostate cancer was used as an example of the numerical model and the Pareto-Optimal Frontier was generated using the method of weighted function.

  8. A research-oriented treatment planning program system

    International Nuclear Information System (INIS)

    Kalet, I.J.; Jacky, J.P.

    1982-01-01

    The function of a treatment planning program is to graphically simulate radiation dose distributions from proposed radiation therapy treatments. While many such programs are available which provide this much-needed service, none addresses the question of how to intercompare calculation and display techniques. This paper describes a program system designed for support of research efforts, particularly development and testing of new calculation algorithms. The system emphasizes a modular flexible structure, enabling programs to be developed somewhat as interchangeable parts. Thus multiple variants of a calculation algorithm can be compared without undue software overhead or additional data management. Unusual features of the system include extensive use of command procedures, logical names and a structured language (PASCAL). These features are described along with other implementation details. Obstacles, limitations and future applications are also discussed. (Auth.)

  9. Treatment planning for children with attention-deficit/hyperactivity disorder: treatment utilization and family preferences

    Directory of Open Access Journals (Sweden)

    William B Brinkman

    2011-01-01

    Full Text Available William B Brinkman, Jeffery N EpsteinDepartment of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USABackground: Attention-deficit/hyperactivity disorder (ADHD is a common condition that often results in child and family functional impairments. Although there are evidence-based treatment modalities available, implementation of and persistence with treatment plans vary with patients. Family preferences also vary and may contribute to variability in treatment utilization.Objective: The objective of this study is to describe the evidence-based treatments available for ADHD, identify patterns of use for each modality, and examine patient and parent treatment preferences.Method: Literature review.Results: Treatment options differ on benefits and risks/costs. Therefore, treatment decisions are preference sensitive and depend on how an informed patient/parent values the tradeoffs between options. Literature on patient and parent ADHD treatment preferences is based on quantitative research assessing the construct of treatment acceptability and qualitative and quantitative research that assesses preferences from a broader perspective. After a child is diagnosed with ADHD, a variety of factors influence the initial selection of treatment modalities that are utilized. Initial parent and child preferences are shaped by their beliefs about the nature of the child's problems and by information (and misinformation received from a variety of sources, including social networks, the media, and health care providers. Subsequently, preferences become further informed by personal experience with various treatment modalities. Over time, treatment plans are revisited and revised as families work with their health care team to establish a treatment plan that helps their child achieve goals while minimizing harms and costs.Conclusions: Studies have not been able to determine the extent to which

  10. Design of 4D treatment planning target volumes

    International Nuclear Information System (INIS)

    Rietzel, Eike; Liu, Arthur K. Ph.D.; Doppke, Karen P.; Wolfgang, John A.; Chen, Aileen B.; Chen, George T.Y.; Choi, Noah C.

    2006-01-01

    Purpose: When using non-patient-specific treatment planning margins, respiratory motion may lead to geometric miss of the target while unnecessarily irradiating normal tissue. Imaging different respiratory states of a patient allows patient-specific target design. We used four-dimensional computed tomography (4DCT) to characterize tumor motion and create treatment volumes in 10 patients with lung cancer. These were compared with standard treatment volumes. Methods and Materials: Four-dimensional CT and free breathing helical CT data of 10 patients were acquired. Gross target volumes (GTV) were delineated on the helical scan as well as on each phase of the 4D data. Composite GTVs were defined on 4DCT. Planning target volumes (PTV) including clinical target volume, internal margin (IM), and setup margin were generated. 4DPTVs with different IMs and standard PTVs were compared by computing centroid positions, volumes, volumetric overlap, and bounding boxes. Results: Four-dimensional PTVs and conventional PTVs differed in volume and centroid positions. Overlap between 4DPTVs generated from two extreme tumor positions only compared with 10 respiratory phases was 93.7%. Comparing PTVs with margins of 15 mm (IM 5 mm) on composite 4D target volumes to PTVs with 20 mm (IM 10 mm) on helical CT data resulted in a decrease in target volume sizes by 23% on average. Conclusion: With patient-specific characterization of tumor motion, it should be possible to decrease internal margins. Patient-specific treatment volumes can be generated using extreme tumor positions on 4DCT. To date, more than 150 patients have been treated using 4D target design

  11. Recent developments in radiation therapy planning and treatment optimization

    International Nuclear Information System (INIS)

    Brahne, A.

    1996-01-01

    Radiation therapy of cancer is today going through a very dynamic development with the introduction of a large number of new treatment principles, new types of treatment units and new radiobiologically based optimization algorithms for treatment planning. All of these make use of the recent developments in three dimensional tumor diagnostics, molecular biology of cancer, the fractionation sensitivity of different tissues and most recently predictive assays of radiation sensitivity. The most efficient but also least developed area of treatment optimization is to use a few non uniform radiation beams directed towards the tumor. Today patient individual collimation with beam blocks or multi leaf collimators protect organs at risk laterally outside the tumor volume. Non uniform dose delivery also allows protection of normal tissues anterior, posterior and even inside the target volume by shaping the isodoses tightly around the tumor tissues and thereby also allowing longitudinal protection of normal tissues. Some of the most advanced new algorithms are even treating therapy optimization as an inverse problem where the optimal incident beam shapes are determined directly from the location of gross disease, presumed microscopic tumor spread and organs at risk. The optimization is then performed such that the probability, P+, to eradicate all clonogenic tumor cells without severely damaging healthy normal tissues is as high as possible. Already with a few non uniform beams the treatment outcome is within a few percent of what can be achieved with infinitely many co-planar beams in a dynamic mood. With such optimized non uniform treatments it should be possible to improve the treatment outcome by as much as 20% and more, particularly in patients with a local complex spread of the disease or several organs at risk. 78 refs., 1 tab., 7 figs

  12. Patient-specific dosimetric endpoints based treatment plan quality control in radiotherapy

    International Nuclear Information System (INIS)

    Song, Ting; Zhou, Linghong; Staub, David; Chen, Mingli; Lu, Weiguo; Tian, Zhen; Jia, Xun; Li, Yongbao; Jiang, Steve B; Gu, Xuejun

    2015-01-01

    In intensity modulated radiotherapy (IMRT), the optimal plan for each patient is specific due to unique patient anatomy. To achieve such a plan, patient-specific dosimetric goals reflecting each patient’s unique anatomy should be defined and adopted in the treatment planning procedure for plan quality control. This study is to develop such a personalized treatment plan quality control tool by predicting patient-specific dosimetric endpoints (DEs). The incorporation of patient specific DEs is realized by a multi-OAR geometry-dosimetry model, capable of predicting optimal DEs based on the individual patient’s geometry. The overall quality of a treatment plan is then judged with a numerical treatment plan quality indicator and characterized as optimal or suboptimal. Taking advantage of clinically available prostate volumetric modulated arc therapy (VMAT) treatment plans, we built and evaluated our proposed plan quality control tool. Using our developed tool, six of twenty evaluated plans were identified as sub-optimal plans. After plan re-optimization, these suboptimal plans achieved better OAR dose sparing without sacrificing the PTV coverage, and the dosimetric endpoints of the re-optimized plans agreed well with the model predicted values, which validate the predictability of the proposed tool. In conclusion, the developed tool is able to accurately predict optimally achievable DEs of multiple OARs, identify suboptimal plans, and guide plan optimization. It is a useful tool for achieving patient-specific treatment plan quality control. (paper)

  13. Integrated Waste Treatment Unit GFSI Risk Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    W. A. Owca

    2007-06-21

    This GFSI Risk Management Plan (RMP) describes the strategy for assessing and managing project risks for the Integrated Waste Treatment Unit (IWTU) that are specifically within the control and purview of the U.S. Department of Energy (DOE), and identifies the risks that formed the basis for the DOE contingency included in the performance baseline. DOE-held contingency is required to cover cost and schedule impacts of DOE activities. Prior to approval of the performance baseline (Critical Decision-2) project cost contingency was evaluated during a joint meeting of the Contractor Management Team and the Integrated Project Team for both contractor and DOE risks to schedule and cost. At that time, the contractor cost and schedule risk value was $41.3M and the DOE cost and schedule risk contingency value is $39.0M. The contractor cost and schedule risk value of $41.3M was retained in the performance baseline as the contractor's management reserve for risk contingency. The DOE cost and schedule risk value of $39.0M has been retained in the performance baseline as the DOE Contingency. The performance baseline for the project was approved in December 2006 (Garman 2006). The project will continue to manage to the performance baseline and change control thresholds identified in PLN-1963, ''Idaho Cleanup Project Sodium-Bearing Waste Treatment Project Execution Plan'' (PEP).

  14. Integrated Waste Treatment Unit GFSI Risk Management Plan

    International Nuclear Information System (INIS)

    W. A. Owca

    2007-01-01

    This GFSI Risk Management Plan (RMP) describes the strategy for assessing and managing project risks for the Integrated Waste Treatment Unit (IWTU) that are specifically within the control and purview of the U.S. Department of Energy (DOE), and identifies the risks that formed the basis for the DOE contingency included in the performance baseline. DOE-held contingency is required to cover cost and schedule impacts of DOE activities. Prior to approval of the performance baseline (Critical Decision-2) project cost contingency was evaluated during a joint meeting of the Contractor Management Team and the Integrated Project Team for both contractor and DOE risks to schedule and cost. At that time, the contractor cost and schedule risk value was $41.3M and the DOE cost and schedule risk contingency value is $39.0M. The contractor cost and schedule risk value of $41.3M was retained in the performance baseline as the contractor's management reserve for risk contingency. The DOE cost and schedule risk value of $39.0M has been retained in the performance baseline as the DOE Contingency. The performance baseline for the project was approved in December 2006 (Garman 2006). The project will continue to manage to the performance baseline and change control thresholds identified in PLN-1963, ''Idaho Cleanup Project Sodium-Bearing Waste Treatment Project Execution Plan'' (PEP)

  15. SU-E-T-24: A Simple Correction-Based Method for Independent Monitor Unit (MU) Verification in Monte Carlo (MC) Lung SBRT Plans

    Energy Technology Data Exchange (ETDEWEB)

    Pokhrel, D; Badkul, R; Jiang, H; Estes, C; Kumar, P; Wang, F [UniversityKansas Medical Center, Kansas City, KS (United States)

    2014-06-01

    Purpose: Lung-SBRT uses hypo-fractionated dose in small non-IMRT fields with tissue-heterogeneity corrected plans. An independent MU verification is mandatory for safe and effective delivery of the treatment plan. This report compares planned MU obtained from iPlan-XVM-Calgorithm against spreadsheet-based hand-calculation using most commonly used simple TMR-based method. Methods: Treatment plans of 15 patients who underwent for MC-based lung-SBRT to 50Gy in 5 fractions for PTV V100%=95% were studied. ITV was delineated on MIP images based on 4D-CT scans. PTVs(ITV+5mm margins) ranged from 10.1- 106.5cc(average=48.6cc). MC-SBRT plans were generated using a combination of non-coplanar conformal arcs/beams using iPlan XVM-Calgorithm (BrainLAB iPlan ver.4.1.2) for Novalis-TX consisting of micro-MLCs and 6MV-SRS (1000MU/min) beam. These plans were re-computed using heterogeneity-corrected Pencil-Beam (PB-hete) algorithm without changing any beam parameters, such as MLCs/MUs. Dose-ratio: PB-hete/MC gave beam-by-beam inhomogeneity-correction-factors (ICFs):Individual Correction. For independent-2nd-check, MC-MUs were verified using TMR-based hand-calculation and obtained an average ICF:Average Correction, whereas TMR-based hand-calculation systematically underestimated MC-MUs by ∼5%. Also, first 10 MC-plans were verified with an ion-chamber measurement using homogenous phantom. Results: For both beams/arcs, mean PB-hete dose was systematically overestimated by 5.5±2.6% and mean hand-calculated MU systematic underestimated by 5.5±2.5% compared to XVMC. With individual correction, mean hand-calculated MUs matched with XVMC by - 0.3±1.4%/0.4±1.4 for beams/arcs, respectively. After average 5% correction, hand-calculated MUs matched with XVMC by 0.5±2.5%/0.6±2.0% for beams/arcs, respectively. Smaller dependence on tumor volume(TV)/field size(FS) was also observed. Ion-chamber measurement was within ±3.0%. Conclusion: PB-hete overestimates dose to lung tumor relative to

  16. Design and Implementation of a Complementary Treatment Planning Software for the GZP6 HDR Brachytherapy System (GZP6 CTPS

    Directory of Open Access Journals (Sweden)

    Sanaz Hariri Tabrizi

    2011-03-01

    Full Text Available Introduction: Brachytherapy is one of the most common treatment modalities for gynecological cancer. The GZP6 brachytherapy system is one of the devices utilized in Iran. It has been considered particularly due to its low cost compared to other more complete and established systems. This system has some deficiencies including lack of a treatment planning software for non-predefined treatments, inability to change the gradually changeable dosimetric variables and using a point source estimation in dose calculation. This report presents a complementary treatment planning software (CTPS to the system’s own dedicated program. Material and Methods: First, the dosimetric characteristics of three GZP6 sources were calculated based on the TG-43 protocol using the MCNP4C Monte Carlo code. Then, the calculated dose distribution around the implanted applicators, based on the selected dwell positions and dwell times, was shown in a graphical user interface (GUI written using the MATLAB software. Results: The computation uncertainty in the resulting TG-43 parameters was about 1% and the calculated parameters were in good agreement with similar studies on cobalt-60 source dosimetry. Furthermore, the GUI is prepared as a user-friendly executable file which can be installed on any operating system. Discussion and Conclusion: Since different patients have distinct anatomy and physical conditions, a program for non-predefined situations of source arrangement is necessary. Using GZP6 CTPS can satisfy this requirement.

  17. Registration and planning of radiotherapy and proton therapy treatment

    International Nuclear Information System (INIS)

    Bausse, Jerome

    2010-01-01

    Within the frame of an update and renewal project, the Orsay Proton Therapy Centre of the Curie Institute (IPCO) renews its software used for the treatment of patients by proton therapy, a radiotherapy technique which uses proton beams. High energies used in these treatments and the precision provided by proton particle characteristics require a more precise patient positioning than conventional radiotherapy: proton therapy requires a precision of about a millimetre. Thus, markers are placed on the skull which are generally well accepted by patients, but are a problem in the case of paediatric treatment, notably for the youngest children whose skull is still growing. The first objective of this research is thus to use only intrinsic information from X-ray images used when positioning the patient. A second objective is to make the new software (TPS Isogray) perfectly compatible with IPCO requirements by maintaining the strengths of the previous TPS (Treatment Planning System) and being prepared to the implementation of a new installation. After a presentation of the context and state of the art in radiotherapy and patient positioning, the author proposes an overview of 2D registration methods, presents a new method for 2x2D registration, and addresses the problem of 3D registration. Then, after a presentation of proton therapy, the author addresses different specific issues and aspects: the compensator (simulation, calculation, and tests), dose calculation, the 'Pencil-Beam' algorithm, tests, and introduced improvements [fr

  18. Adaptive modification of treatment planning to minimize the deleterious effects of treatment setup errors

    International Nuclear Information System (INIS)

    Yan Di; Wong, John; Vicini, Frank; Michalski, Jeff; Pan Cheng; Frazier, Arthur; Horwitz, Eric; Martinez, Alvaro

    1997-01-01

    Purpose: Using daily setup variation measured from an electronic portal imaging device (EPID), radiation treatment of the individual patient can be adaptively reoptimized during the course of therapy. In this study, daily portal images were retrospectively examined to: (a) determine the number of initial days of portal imaging required to give adequate prediction of the systematic and random setup errors; and (b) explore the potential of using the prediction as feedback to reoptimize the individual treatment part-way through the treatment course. Methods and Materials: Daily portal images of 64 cancer patients, whose treatment position was not adjusted during the course of treatment, were obtained from two independent clinics with similar setup procedures. Systematic and random setup errors for each patient were predicted using different numbers of initial portal measurements. The statistical confidence of the predictions was tested to determine the number of daily portal measurements needed to give reasonable predictions. Two treatment processes were simulated to examine the potential opportunity for setup margin reduction and dose escalation. The first process mimicked a conventional treatment. A constant margin was assigned to each treatment field to compensate for the average setup error of the patient population. A treatment dose was then prescribed with reference to a fixed normal tissue tolerance, and then fixed in the entire course of treatment. In the second process, the same treatment fields and prescribed dose were used only for the initial plan and treatment. After several initial days of treatments, the treatment field shape and position were assumed to be adaptively modified using a computer-controlled multileaf collimator (MLC) in light of the predicted systematic and random setup errors. The prescribed dose was then escalated until the same normal tissue tolerance, as determined in the first treatment process, was reached. Results: The systematic

  19. Treatment planning: A key milestone to prevent treatment dropout in adolescents with borderline personality disorder.

    Science.gov (United States)

    Desrosiers, Lyne; Saint-Jean, Micheline; Breton, Jean-Jacques

    2015-06-01

    The aim of this study was to gain a broader appreciation of processes involved in treatment dropout in adolescents with borderline personality disorder (BPD). A constructivist grounded theory was chosen using a multiple-case research design with three embedded levels of analysis (adolescent, parent, and care setting). Theoretical sampling and the different stages of analysis specific to grounded theory were performed according to the iterative process of constant comparative analysis. Twelve cases were examined (nine dropouts among adolescents with BPD and for the purpose of falsification, one dropout of suicidal adolescent without BPD and two completed treatments among adolescents with BPD). To document the cases, three groups of informants were recruited (adolescents, parents, and therapists involved in the treatment) and 34 interviews were conducted. Psychological characteristics, perception of mental illness and mental health care, and help-seeking context were the specific treatment dropout vulnerabilities identified in adolescents with BPD and in their parents. However, their disengagement became an issue only when care-setting response--including mitigation of accessibility problems, adaptation of services to needs of adolescents with BPD, preparation for treatment, and concern for clinicians' disposition to treat--was ill-suited to these treatment dropout vulnerabilities. Treatment planning proves to be a key milestone to properly engage adolescents with BPD and their parent. Systematic assessment of treatment dropout vulnerabilities before the intervention plan is laid out could foster better-suited responses of the care setting thus decreasing the incidence of treatment discontinuation in adolescents with BPD. Treatment dropout vulnerabilities specific to adolescents with BPD and their parents can be detected before the beginning of treatment. Premature treatment termination may be prevented if the care setting considers these vulnerabilities at treatment

  20. 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

  1. Treatment planning for prostate focal laser ablation in the face of needle placement uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Cepek, Jeremy, E-mail: jcepek@robarts.ca; Fenster, Aaron [Robarts Research Institute, London, Ontario N6A 5K8, Canada and Biomedical Engineering, The University of Western Ontario, London, Ontario N6A 5B9 (Canada); Lindner, Uri; Trachtenberg, John [Department of Surgical Oncology, Division of Urology, University Health Network, Toronto, Ontario M5G 2C4 (Canada); Davidson, Sean R. H. [Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2M9 (Canada); Haider, Masoom A. [Department of Medical Imaging, Sunnybrook Health Sciences Center, Toronto, Ontario M4N 3M5, Canada and Department of Medical Imaging, University of Toronto, Toronto, Ontario M5S 2J7 (Canada); Ghai, Sangeet [Department of Medical Imaging, University Health Network, Toronto, Ontario M5G 2M9 (Canada)

    2014-01-15

    Purpose: To study the effect of needle placement uncertainty on the expected probability of achieving complete focal target destruction in focal laser ablation (FLA) of prostate cancer. Methods: Using a simplified model of prostate cancer focal target, and focal laser ablation region shapes, Monte Carlo simulations of needle placement error were performed to estimate the probability of completely ablating a region of target tissue. Results: Graphs of the probability of complete focal target ablation are presented over clinically relevant ranges of focal target sizes and shapes, ablation region sizes, and levels of needle placement uncertainty. In addition, a table is provided for estimating the maximum target size that is treatable. The results predict that targets whose length is at least 5 mm smaller than the diameter of each ablation region can be confidently ablated using, at most, four laser fibers if the standard deviation in each component of needle placement error is less than 3 mm. However, targets larger than this (i.e., near to or exceeding the diameter of each ablation region) require more careful planning. This process is facilitated by using the table provided. Conclusions: The probability of completely ablating a focal target using FLA is sensitive to the level of needle placement uncertainty, especially as the target length approaches and becomes greater than the diameter of ablated tissue that each individual laser fiber can achieve. The results of this work can be used to help determine individual patient eligibility for prostate FLA, to guide the planning of prostate FLA, and to quantify the clinical benefit of using advanced systems for accurate needle delivery for this treatment modality.

  2. Total variation superiorization in dual-energy CT reconstruction for proton therapy treatment planning

    Science.gov (United States)

    Zhu, Jiahua; Penfold, Scott

    2017-04-01

    Proton therapy is a precise form of radiotherapy in which the range of an energetic beam of protons within a patient must be accurately known. The current approach based on single-energy computed tomography (SECT) can lead to uncertainties in the proton range of approximately 3%. This range of uncertainty may lead to under-dosing of the tumour or over-dosing of healthy tissues. Dual-energy CT (DECT) theoretically has the potential to reduce these range uncertainties by quantifying electron density and the effective atomic number. In practice, however, DECT images reconstructed with filtered backprojection (FBP) tend to suffer from high levels of noise. The objective of the current work was to examine the effect of total variation superiorization (TVS) on proton therapy planning accuracy when compared with FBP. A virtual CT scanner was created with the Monte Carlo toolkit Geant4. Tomographic images were reconstructed with FBP and TVS combined with diagonally relaxed orthogonal projections (TVS-DROP). A total variation minimization (TVM) filter was also applied to the image reconstructed with FBP (FBP-TVM). Quantitative accuracy and variance of proton relative stopping power (RSP) derived from each image set was assessed. Mean RSPs were comparable with each image; however, the standard deviation of pixel values with TVS-DROP was reduced by a factor of 0.44 compared with the FBP image and a factor of 0.66 when compared with the FBP-TVM image. Proton doses calculated with the TVS-DROP image set were also better able to predict a reference dose distribution when compared with the FBP and FBP-TVM image sets. The study demonstrated the potential advantages of TVS-DROP as an image reconstruction method for DECT applied to proton therapy treatment planning.

  3. Microbeam radiation therapy. Physical and biological aspects of a new cancer therapy and development of a treatment planning system

    Energy Technology Data Exchange (ETDEWEB)

    Bartzsch, Stefan

    2014-11-05

    Microbeam Radiation Therapy (MRT) is a novel treatment strategy against cancer. Highly brilliant synchrotron radiation is collimated to parallel, a few micrometre wide, planar beams and used to irradiate malignant tissues with high doses. The applied peak doses are considerably higher than in conventional radiotherapy, but valley doses between the beams remain underneath the established tissue tolerance. Previous research has shown that these beam geometries spare normal tissue, while being effective in tumour ablation. In this work physical and biological aspects of the therapy were investigated. A therapy planning system was developed for the first clinical treatments at the European Synchrotron Radiation Facility in Grenoble (France) and a dosimetry method based on radiochromic films was created to validate planned doses with measurements on a micrometre scale. Finally, experiments were carried out on a cellular level in order to correlate the physically planned doses with the biological damage caused in the tissue. The differences between Monte Carlo dose and dosimetry are less than 10% in the valley and 5% in the peak regions. Developed alternative faster dose calculation methods deviate from the computational intensive MC simulations by less than 15% and are able to determine the dose within a few minutes. The experiments in cell biology revealed an significant influence of intercellular signalling on the survival of cells close to radiation boundaries. These observations may not only be important for MRT but also for conventional radiotherapy.

  4. A review of treatment planning for precision image-guided photon beam pre-clinical animal radiation studies.

    Science.gov (United States)

    Verhaegen, Frank; van Hoof, Stefan; Granton, Patrick V; Trani, Daniela

    2014-12-01

    Recently, precision irradiators integrated with a high-resolution CT imaging device became available for pre-clinical studies. These research platforms offer significant advantages over older generations of animal irradiators in terms of precision and accuracy of image-guided radiation targeting. These platforms are expected to play a significant role in defining experiments that will allow translation of research findings to the human clinical setting. In the field of radiotherapy, but also others such as neurology, the platforms create unique opportunities to explore e.g. the synergy between radiation and drugs or other agents. To fully exploit the advantages of this new technology, accurate methods are needed to plan the irradiation and to calculate the three-dimensional radiation dose distribution in the specimen. To this end, dedicated treatment planning systems are needed. In this review we will discuss specific issues for precision irradiation of small animals, we will describe the workflow of animal treatment planning, and we will examine several dose calculation algorithms (factorization, superposition-convolution, Monte Carlo simulation) used for animal irradiation with kilovolt photon beams. Issues such as dose reporting methods, photon scatter, tissue segmentation and motion will also be discussed briefly. Copyright © 2014. Published by Elsevier GmbH.

  5. Verification of computerized treatment planning for HDR 192Ir brachytherapy for gynaecological cancer.

    Science.gov (United States)

    Buzdar, Saeed Ahmad; Gadhi, Muhammad Asghar; Rao, Muhammad Afzal; Laghari, Naeem Ahmad; Anees, Mohammad

    2009-02-01

    Treatment planning in both teletherapy and brachytherapy is time consuming practice but accurate determination of planning parameters is more important. This paper aims to verify the dose delivery time for the treatment of vaginal cancer, which is a vital parameter of High Dose Rate (HDR) brachytherapy treatment planning. Treatment time has been calculated by the computerized treatment planning system (ABACUS 3.1), and then it has been compared with the manually calculated time. The results obtained are in good agreement. Independent verification of nominal time by two different protocols assures the quality of treatment. This should always be practiced to increase the accuracy of treatment.

  6. SU-G-BRC-02: A Novel Multi-Criteria Optimization Approach to Generate Deliverable Intensity-Modulated Radiation Therapy (IMRT) Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Kirlik, G; D’Souza, W; Zhang, H [University of Maryland School of Medicine, Baltimore, MD (United States)

    2016-06-15

    Purpose: To present a novel multi-criteria optimization (MCO) solution approach that generates treatment plans with deliverable apertures using column generation. Methods: We demonstrate our method with 10 locally advanced head-and-neck cancer cases retrospectively. In our MCO formulation, we defined an objective function for each structure in the treatment volume. This resulted in 9 objective functions, including 3 distinct objectives for primary target volume, high-risk and low-risk target volumes, 5 objectives for each of the organs-at-risk (OARs) (two parotid glands, spinal cord, brain stem and oral cavity), and one for the non-target non-OAR normal tissue. Conditional value-at-risk (CVaR) constraints were utilized to ensure at least certain fraction of the target volumes receiving the prescription doses. To directly generate deliverable plans, column generation algorithm was embedded within our MCO approach for aperture shape generation. Final dose distributions for all plans were generated using a Monte Carlo kernel-superposition dose calculation. We compared the MCO plans with the clinical plans, which were created by clinicians. Results: At least 95% target coverage was achieved by both MCO plans and clinical plans. However, the average conformity indices of clinical plans and the MCO plans were 1.95 and 1.35, respectively (31% reduction, p<0.01). Compared to the conventional clinical plan, the proposed MCO method achieved average reductions in left parotid mean dose of 5% (p=0.06), right parotid mean dose of 18% (p<0.01), oral cavity mean dose of 21% (p=0.03), spinal cord maximum dose of 20% (p<0.01), brain stem maximum dose of 61% (p<0.01), and normal tissue maximum dose of 5% (p<0.01), respectively. Conclusion: We demonstrated that the proposed MCO method was able to obtain deliverable IMRT treatment plans while achieving significant improvements in dosimetric plan quality.

  7. Technical Basis for Radiological Emergency Plan Annex for WTD Emergency Response Plan: West Point Treatment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hickey, Eva E.; Strom, Daniel J.

    2005-08-01

    Staff of the King County Wastewater Treatment Division (WTD) have concern about the aftermath of a radiological dispersion event (RDE) leading to the introduction of significant quantities of radioactive material into the combined sanitary and storm sewer system in King County, Washington. Radioactive material could come from the use of a radiological dispersion device (RDD). RDDs include "dirty bombs" that are not nuclear detonations but are explosives designed to spread radioactive material (National Council on Radiation Protection and Measurements (NCRP) 2001). Radioactive material also could come from deliberate introduction or dispersion of radioactive material into the environment, including waterways and water supply systems. This document, Volume 3 of PNNL-15163 is the technical basis for the Annex to the West Point Treatment Plant (WPTP) Emergency Response Plan related to responding to a radiological emergency at the WPTP. The plan primarily considers response to radioactive material that has been introduced in the other combined sanitary and storm sewer system from a radiological dispersion device, but is applicable to any accidental or deliberate introduction of materials into the system.

  8. Specification and acceptance testing of radiotherapy treatment planning systems

    International Nuclear Information System (INIS)

    2007-04-01

    Quality assurance (QA) in the radiation therapy treatment planning process is essential to ensure accurate dose delivery to the patient and to minimize the possibility of accidental exposure. The computerized radiotherapy treatment planning systems (RTPSs) are now widely available in industrialized and developing countries and it is of special importance to support hospitals in Member States in developing procedures for acceptance testing, commissioning and QA of their RTPSs. Responding to these needs, a group of experts developed an IAEA publication with such recommendations, which was published in 2004 as IAEA Technical Reports Series No. 430. This report provides a general framework and describes a large number of tests and procedures that should be considered by the users of new RTPSs. However, small hospitals with limited resources or large hospitals with high patient load and limited staff are not always able to perform complete characterization, validation and software testing of algorithms used in RTPSs. Therefore, the IAEA proposed more specific guidelines that provide a step-by-step recommendation for users at hospitals or cancer centres how to implement acceptance and commissioning procedures for newly purchased RTPSs. The current publication was developed in the framework of the Coordinated Research Project on Development of Procedures for Quality Assurance for Dosimetry Calculations in Radiotherapy and uses the International Electrotechnical Commission (IEC) standard IEC 62083, Requirements for the Safety of Radiotherapy Treatment Planning Systems as its basis. The report addresses the procedures for specification and acceptance testing of RTPSs to be used by both manufacturers and users at the hospitals. Recommendations are provided for specific tests to be performed at the manufacturing facility known as type tests, and for acceptance tests to be performed at the hospital known as site tests. The purpose of acceptance testing is to demonstrate to the

  9. 3718-F Alkali Metal Treatment and Storage Facility Closure Plan

    International Nuclear Information System (INIS)

    1992-11-01

    The Hanford Site, located northwest of the city of Richland, Washington, houses reactors, chemical-separation systems, and related facilities used for the production of special nuclear materials, as well as for activities associated with nuclear energy development. The 300 Area of the Hanford Site contains reactor fuel manufacturing facilities and several research and development laboratories. The 3718-F Alkali Metal Treatment and Storage Facility (3718-F Facility), located in the 300 Area, was used to store and treat alkali metal wastes. Therefore, it is subject to the regulatory requirements for the storage and treatment of dangerous wastes. Closure will be conducted pursuant to the requirements of the Washington Administrative Code (WAC) 173-303-610 (Ecology 1989) and 40 CFR 270.1. Closure also will satisfy the thermal treatment facility closure requirements of 40 CFR 265.381. This closure plan presents a description of the 3718-F Facility, the history of wastes managed, and the approach that will be followed to close the facility. Only hazardous constituents derived from 3718-F Facility operations will be addressed

  10. Ranking radiotherapy treatment plans using decision-analytic and heuristic techniques.

    OpenAIRE

    Jain, N. L.; Kahn, M. G.

    1991-01-01

    Radiotherapy treatment optimization is done by generating a set of tentative treatment plans, evaluating them and selecting the plan closest to achieving a set of conflicting treatment objectives. The evaluation of potential plans involves making tradeoffs among competing possible outcomes. Multiattribute decision theory provides a framework for specifying such tradeoffs and using them to select optimal actions. Using these concepts, we have developed a plan-ranking model which ranks a set of...

  11. Plans and Progress on Hanford MLLW Treatment and Disposal

    International Nuclear Information System (INIS)

    McDonald, K. M.; Blackford, L. T.; Nester, D. E.; Connolly, R. R.; McKenney, D. E.; Moy, S. K.

    2003-01-01

    Mixed low-level waste (MLLW) contains both low-level radioactive materials and low-level hazardous chemicals. The hazardous component of mixed waste has characteristics identified by any or all of the following statutes: the Resource Conservation and Recovery Act of 1976 (RCRA), as amended; the Toxic Substances Control Act of 1976; and Washington State dangerous waste regulations. The Fluor Hanford Waste Management Project (WMP) is responsible for storing, treating, and disposing of solid MLLW, which includes organic and inorganic solids, organics and inorganic lab packs, debris, lead, mercury, long-length equipment, spent melters, and remote-handled (RH) and oversized MLLW. Hanford has 7,000 cubic meters, or about 25%, of the MLLW in storage at U.S. Department of Energy (DOE) sites. Hanford plans to receive 57,000 cubic meters from on-site generators, or about 50% of DOE's newly generated MLLW. In addition, the Hanford Environment Restoration Program and off-site generators having approved Federal Facility Consent Agreement site treatment plans will most likely send 200 cubic meters of waste to be treated and returned to the generators. Volumes of off-site waste receipts will be affected when the MLLW Record of Decision is issued as part of the process for the Hanford Site Solid Waste Environmental Impact Statement (EIS). The WMP objective relative to MLLW is to treat and dispose of ∼8000 cubic meters of existing inventory and newly-generated waste by September 30, 2006

  12. Dosimetry audit simulation of treatment planning system in multicenters radiotherapy

    Science.gov (United States)

    Kasmuri, S.; Pawiro, S. A.

    2017-07-01

    Treatment Planning System (TPS) is an important modality that determines radiotherapy outcome. TPS requires input data obtained through commissioning and the potentially error occurred. Error in this stage may result in the systematic error. The aim of this study to verify the TPS dosimetry to know deviation range between calculated and measurement dose. This study used CIRS phantom 002LFC representing the human thorax and simulated all external beam radiotherapy stages. The phantom was scanned using CT Scanner and planned 8 test cases that were similar to those in clinical practice situation were made, tested in four radiotherapy centers. Dose measurement using 0.6 cc ionization chamber. The results of this study showed that generally, deviation of all test cases in four centers was within agreement criteria with average deviation about -0.17±1.59 %, -1.64±1.92 %, 0.34±1.34 % and 0.13±1.81 %. The conclusion of this study was all TPS involved in this study showed good performance. The superposition algorithm showed rather poor performance than either analytic anisotropic algorithm (AAA) and convolution algorithm with average deviation about -1.64±1.92 %, -0.17±1.59 % and -0.27±1.51 % respectively.

  13. The 300 area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    Luke, S.N.

    1996-01-01

    The 300 Area Waste Acid Treatment System (WATS) is located within operable units 300-FF-2 (source) and 300-FF-5 (groundwater), as designated in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) . Operable units 300-FF-2 and 300-FF-5 are scheduled to be remediated using the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Remedial Investigation/Feasibility Study (RI/FS) process. Thus, any remediation of the 300 Area WATS with respect to contaminants not produced by those facilities and soils and groundwater will be deferred to the CERCLA RI/FS process. Final closure activities will be completed in 3 phases and certified in accordance with the 300 Area WATS closure plan by the Washington State Department of Ecology (Ecology) and the U.S. Environmental Protection Agency (EPA). It is anticipated that the 300 Area WATS closure would take 2 years to complete

  14. CBCT analysis of three implant cases for treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Duk; Kim, Kwang Won; Lim, Sung Hoon [Chosun Univ. School of Dentistry, Gwangju (Korea, Republic of)

    2007-09-15

    The role of radiographic imaging in determining the size, numbers and the position of implants is very important. To perform the implant procedure, the dentist needs to evaluate the bone pathology and bone density, and to know the precise height, width, and contour of the alveolar process, as well as its relationship to the maxillary sinus and mandibular canal. The author analyzed 3 implant cases for treatment planning with the cone beam CT. All axial, panoramic, serial and buccolingual-sectioned images of 3 cases with stent including vertical marker were taken by using Mercury (Hitachi, Japan). When the curved line drawn intentionally did nor include dot image of a vertical marker on the axial image of CBCT, the image of the vertical marker was deformed on its buccolingually sectioned image. There was wide discrepancy in inclination between the alveolar bone and tooth on buccolingually sectioned image.

  15. Treatment planning and smile design using composite resin.

    Science.gov (United States)

    Marus, Robert

    2006-05-01

    Recent advances in dental materials and adhesive protocols have expanded the restorative procedures available to today's clinicians. Used in combination with proper treatment planning, these innovations enable dental professionals to provide enhanced aesthetic care that achieves the increasing expectations of their patients. Using a case presentation, this article will document the steps required to harmoniously integrate smile design, material selection, and patient communication that are involved in the provisional of aesthetic dental care. This article discusses the utilization of composite resin as a tool to enhance the patient's smile. Upon reading this article, the reader should: Become familiar with a smile-enhancing technique which can be completed in one office visit. Realize the benefits that intraoral composite mockups offer in terms of prototyping and confirming patient satisfaction.

  16. MO-B-BRB-03: Systems Engineering Tools for Treatment Planning Process Optimization in Radiation Medicine

    International Nuclear Information System (INIS)

    Kapur, A.

    2015-01-01

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  17. MO-B-BRB-02: Maintain the Quality of Treatment Planning for Time-Constraint Cases

    International Nuclear Information System (INIS)

    Chang, J.

    2015-01-01

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  18. MO-B-BRB-03: Systems Engineering Tools for Treatment Planning Process Optimization in Radiation Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Kapur, A. [Long Island Jewish Medical Center (United States)

    2015-06-15

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  19. MO-B-BRB-02: Maintain the Quality of Treatment Planning for Time-Constraint Cases

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J. [New York Weill Cornell Medical Ctr (United States)

    2015-06-15

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  20. MO-B-BRB-01: Optimize Treatment Planning Process in Clinical Environment

    Energy Technology Data Exchange (ETDEWEB)

    Feng, W. [New York Presbyterian Hospital (United States)

    2015-06-15

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  1. A DVH-guided IMRT optimization algorithm for automatic treatment planning and adaptive radiotherapy replanning

    International Nuclear Information System (INIS)

    Zarepisheh, Masoud; Li, Nan; Long, Troy; Romeijn, H. Edwin; Tian, Zhen; Jia, Xun; Jiang, Steve B.

    2014-01-01

    Purpose: To develop a novel algorithm that incorporates prior treatment knowledge into intensity modulated radiation therapy optimization to facilitate automatic treatment planning and adaptive radiotherapy (ART) replanning. Methods: The algorithm automatically creates a treatment plan guided by the DVH curves of a reference plan that contains information on the clinician-approved dose-volume trade-offs among different targets/organs and among different portions of a DVH curve for an organ. In ART, the reference plan is the initial plan for the same patient, while for automatic treatment planning the reference plan is selected from a library of clinically approved and delivered plans of previously treated patients with similar medical conditions and geometry. The proposed algorithm employs a voxel-based optimization model and navigates the large voxel-based Pareto surface. The voxel weights are iteratively adjusted to approach a plan that is similar to the reference plan in terms of the DVHs. If the reference plan is feasible but not Pareto optimal, the algorithm generates a Pareto optimal plan with the DVHs better than the reference ones. If the reference plan is too restricting for the new geometry, the algorithm generates a Pareto plan with DVHs close to the reference ones. In both cases, the new plans have similar DVH trade-offs as the reference plans. Results: The algorithm was tested using three patient cases and found to be able to automatically adjust the voxel-weighting factors in order to generate a Pareto plan with similar DVH trade-offs as the reference plan. The algorithm has also been implemented on a GPU for high efficiency. Conclusions: A novel prior-knowledge-based optimization algorithm has been developed that automatically adjust the voxel weights and generate a clinical optimal plan at high efficiency. It is found that the new algorithm can significantly improve the plan quality and planning efficiency in ART replanning and automatic treatment

  2. Summary and recommendations of a National Cancer Institute workshop on issues limiting the clinical use of Monte Carlo dose calculation algorithms for megavoltage external beam radiation therapy

    International Nuclear Information System (INIS)

    Fraass, Benedick A.; Smathers, James; Deye, James

    2003-01-01

    Due to the significant interest in Monte Carlo dose calculations for external beam megavoltage radiation therapy from both the research and commercial communities, a workshop was held in October 2001 to assess the status of this computational method with regard to use for clinical treatment planning. The Radiation Research Program of the National Cancer Institute, in conjunction with the Nuclear Data and Analysis Group at the Oak Ridge National Laboratory, gathered a group of experts in clinical radiation therapy treatment planning and Monte Carlo dose calculations, and examined issues involved in clinical implementation of Monte Carlo dose calculation methods in clinical radiotherapy. The workshop examined the current status of Monte Carlo algorithms, the rationale for using Monte Carlo, algorithmic concerns, clinical issues, and verification methodologies. Based on these discussions, the workshop developed recommendations for future NCI-funded research and development efforts. This paper briefly summarizes the issues presented at the workshop and the recommendations developed by the group

  3. Automation and Intensity Modulated Radiation Therapy for Individualized High-Quality Tangent Breast Treatment Plans

    International Nuclear Information System (INIS)

    Purdie, Thomas G.; Dinniwell, Robert E.; Fyles, Anthony; Sharpe, Michael B.

    2014-01-01

    Purpose: To demonstrate the large-scale clinical implementation and performance of an automated treatment planning methodology for tangential breast intensity modulated radiation therapy (IMRT). Methods and Materials: Automated planning was used to prospectively plan tangential breast IMRT treatment for 1661 patients between June 2009 and November 2012. The automated planning method emulates the manual steps performed by the user during treatment planning, including anatomical segmentation, beam placement, optimization, dose calculation, and plan documentation. The user specifies clinical requirements of the plan to be generated through a user interface embedded in the planning system. The automated method uses heuristic algorithms to define and simplify the technical aspects of the treatment planning process. Results: Automated planning was used in 1661 of 1708 patients receiving tangential breast IMRT during the time interval studied. Therefore, automated planning was applicable in greater than 97% of cases. The time for treatment planning using the automated process is routinely 5 to 6 minutes on standard commercially available planning hardware. We have shown a consistent reduction in plan rejections from plan reviews through the standard quality control process or weekly quality review multidisciplinary breast rounds as we have automated the planning process for tangential breast IMRT. Clinical plan acceptance increased from 97.3% using our previous semiautomated inverse method to 98.9% using the fully automated method. Conclusions: Automation has become the routine standard method for treatment planning of tangential breast IMRT at our institution and is clinically feasible on a large scale. The method has wide clinical applicability and can add tremendous efficiency, standardization, and quality to the current treatment planning process. The use of automated methods can allow centers to more rapidly adopt IMRT and enhance access to the documented

  4. Scanned ion beam therapy for prostate carcinoma. Comparison of single plan treatment and daily plan-adapted treatment

    International Nuclear Information System (INIS)

    Hild, Sebastian; Graeff, Christian; Rucinski, Antoni; Zink, Klemens; Habl, Gregor; Durante, Marco; Herfarth, Klaus; Bert, Christoph

    2016-01-01

    Intensity-modulated particle therapy (IMPT) for tumors showing interfraction motion is a topic of current research. The purpose of this work is to compare three treatment strategies for IMPT to determine potential advantages and disadvantages of ion prostate cancer therapy. Simulations for three treatment strategies, conventional one-plan radiotherapy (ConvRT), image-guided radiotherapy (IGRT), and online adaptive radiotherapy (ART) were performed employing a dataset of 10 prostate cancer patients with six CT scans taken at one week intervals. The simulation results, using a geometric margin concept (7-2 mm) as well as patient-specific internal target volume definitions for IMPT were analyzed by target coverage and exposure of critical structures on single fraction dose distributions. All strategies led to clinically acceptable target coverage in patients exhibiting small prostate motion (mean displacement < 4 mm), but IGRT and especially ART led to significant sparing of the rectum. In 20 % of the patients, prostate motion exceeded 4 mm causing insufficient target coverage for ConvRT (V95 mean = 0.86, range 0.63-0.99) and IGRT (V95 mean = 0.91, range 0.68-1.00), while ART maintained acceptable target coverage. IMPT of prostate cancer demands consideration of rectal sparing and adaptive treatment replanning for patients exhibiting large prostate motion. (orig.) [de

  5. 45 CFR 146.180 - Treatment of non-Federal governmental plans.

    Science.gov (United States)

    2010-10-01

    ... the next business day. (3) Failure to respond timely. CMS may invalidate an election if the plan...-Federal governmental plan the right to exempt the plan in whole, or in part, from the listed requirements... 45 Public Welfare 1 2010-10-01 2010-10-01 false Treatment of non-Federal governmental plans. 146...

  6. MO-D-BRB-02: Pediatric Treatment Planning II: Applications of Proton Beams for Pediatric Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hua, C. [St. Jude Childrens Research Hospital (United States)

    2015-06-15

    Most Medical Physicists working in radiotherapy departments see few pediatric patients. This is because, fortunately, children get cancer at a rate nearly 100 times lower than adults. Children have not smoked, abused alcohol, or been exposed to environmental carcinogens for decades, and of course, have not fallen victim to the aging process. Children get very different cancers than adults. Breast or prostate cancers, typical in adults, are rarely seen in children but instead a variety of tumors occur in children that are rarely seen in adults; examples are germinomas, ependymomas and primitive neuroectodermal tumors, which require treatment of the child’s brain or neuroblastoma, requiring treatment in the abdomen. The treatment of children with cancer using radiation therapy is one of the most challenging planning and delivery problems facing the physicist. This is because bones, brain, breast tissue, and other organs are more sensitive to radiation in children than in adults. Because most therapy departments treat mostly adults, when the rare 8 year-old patient comes to the department for treatment, the physicist may not understand the clinical issues of his disease which drive the planning and delivery decisions. Additionally, children are more prone than adults to developing secondary cancers after radiation. For bilateral retinoblastoma for example, an irradiated child has a 40% chance of developing a second cancer by age 50. The dosimetric tradeoffs made during the planning process are complex and require careful consideration for children treated with radiotherapy. In the first presentation, an overview of childhood cancers and their corresponding treatment techniques will be given. These can be some of the most complex treatments that are delivered in the radiation therapy department. These cancers include leukemia treated with total body irradiation, medulloblastoma, treated with craniospinal irradiation plus a conformal boost to the posterior fossa

  7. MO-D-BRB-02: Pediatric Treatment Planning II: Applications of Proton Beams for Pediatric Treatment

    International Nuclear Information System (INIS)

    Hua, C.

    2015-01-01

    Most Medical Physicists working in radiotherapy departments see few pediatric patients. This is because, fortunately, children get cancer at a rate nearly 100 times lower than adults. Children have not smoked, abused alcohol, or been exposed to environmental carcinogens for decades, and of course, have not fallen victim to the aging process. Children get very different cancers than adults. Breast or prostate cancers, typical in adults, are rarely seen in children but instead a variety of tumors occur in children that are rarely seen in adults; examples are germinomas, ependymomas and primitive neuroectodermal tumors, which require treatment of the child’s brain or neuroblastoma, requiring treatment in the abdomen. The treatment of children with cancer using radiation therapy is one of the most challenging planning and delivery problems facing the physicist. This is because bones, brain, breast tissue, and other organs are more sensitive to radiation in children than in adults. Because most therapy departments treat mostly adults, when the rare 8 year-old patient comes to the department for treatment, the physicist may not understand the clinical issues of his disease which drive the planning and delivery decisions. Additionally, children are more prone than adults to developing secondary cancers after radiation. For bilateral retinoblastoma for example, an irradiated child has a 40% chance of developing a second cancer by age 50. The dosimetric tradeoffs made during the planning process are complex and require careful consideration for children treated with radiotherapy. In the first presentation, an overview of childhood cancers and their corresponding treatment techniques will be given. These can be some of the most complex treatments that are delivered in the radiation therapy department. These cancers include leukemia treated with total body irradiation, medulloblastoma, treated with craniospinal irradiation plus a conformal boost to the posterior fossa

  8. Investigating the robustness of ion beam therapy treatment plans to uncertainties in biological treatment parameters

    CERN Document Server

    Boehlen, T T; Dosanjh, M; Ferrari, A; Fossati, P; Haberer, T; Mairani, A; Patera, V

    2012-01-01

    Uncertainties in determining clinically used relative biological effectiveness (RBE) values for ion beam therapy carry the risk of absolute and relative misestimations of RBE-weighted doses for clinical scenarios. This study assesses the consequences of hypothetical misestimations of input parameters to the RBE modelling for carbon ion treatment plans by a variational approach. The impact of the variations on resulting cell survival and RBE values is evaluated as a function of the remaining ion range. In addition, the sensitivity to misestimations in RBE modelling is compared for single fields and two opposed fields using differing optimization criteria. It is demonstrated for single treatment fields that moderate variations (up to +/-50\\%) of representative nominal input parameters for four tumours result mainly in a misestimation of the RBE-weighted dose in the planning target volume (PTV) by a constant factor and only smaller RBE-weighted dose gradients. Ensuring a more uniform radiation quality in the PTV...

  9. Groups as a part of integrated treatment plans : Inpatient psychotherapy for outpatients?

    NARCIS (Netherlands)

    Staats, H

    2005-01-01

    Group psychotherapy in Germany is well established as part of an integrative treatment plan in inpatient treatment. Outpatient group psychotherapy, however, is conceptualized as a separate treatment option in competition with individual therapy. German guidelines for outpatient psychotherapy exclude

  10. Incorporating organ movements in IMRT treatment planning for prostate cancer: Minimizing uncertainties in the inverse planning process

    International Nuclear Information System (INIS)

    Unkelbach, Jan; Oelfke, Uwe

    2005-01-01

    We investigate an off-line strategy to incorporate inter fraction organ movements in IMRT treatment planning. Nowadays, imaging modalities located in the treatment room allow for several CT scans of a patient during the course of treatment. These multiple CT scans can be used to estimate a probability distribution of possible patient geometries. This probability distribution can subsequently be used to calculate the expectation value of the delivered dose distribution. In order to incorporate organ movements into the treatment planning process, it was suggested that inverse planning could be based on that probability distribution of patient geometries instead of a single snapshot. However, it was shown that a straightforward optimization of the expectation value of the dose may be insufficient since the expected dose distribution is related to several uncertainties: first, this probability distribution has to be estimated from only a few images. And second, the distribution is only sparsely sampled over the treatment course due to a finite number of fractions. In order to obtain a robust treatment plan these uncertainties should be considered and minimized in the inverse planning process. In the current paper, we calculate a 3D variance distribution in addition to the expectation value of the dose distribution which are simultaniously optimized. The variance is used as a surrogate to quantify the associated risks of a treatment plan. The feasibility of this approach is demonstrated for clinical data of prostate patients. Different scenarios of dose expectation values and corresponding variances are discussed

  11. Safety Improvement in Radiotherapy Treatment Plan. Planning vs Redundant Check vs in vivo Dosimetry

    International Nuclear Information System (INIS)

    Torres Diaz, J.; Ascencion Ybarra, Y.; La Fuentes Rosales, L. de; Lara Mas, E.; Larrinaga Cortinas, E.

    2013-01-01

    In Cuba it is mandatory to have an independent monitor units check before any radiotherapy treatment is started. The main objective of this paper is to enhance the safety of the radiotherapy planning by developing and testing a practical tool to double check the monitor units calculation for external beam high energy photon therapy. A software for monitor units (MUs) verification was designed and coded. It considers the common in clinical practice isocentric set-ups. The in vivo dosimetry measurements were done with a silicon diode system for 6 MV photon beams to support the validation of the software. The results show a discrepancy within 5% between the 3 methods which is in accordance with international recommendations. (Author)

  12. 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

  13. Assessments for High Dose Radionuclide Therapy Treatment Planning

    International Nuclear Information System (INIS)

    Fisher, Darrell R.

    2003-10-01

    Advances in the biotechnology of cell-specific targeting of cancer, and the increased number of clinical trials involving treatment of cancer patients with radiolabeled antibodies, peptides, and similar delivery vehicles have led to an increase in the number of high-dose radionuclide therapy procedures. Optimized radionuclide therapy for cancer treatment is based on the concept of absorbed dose to the dose-limiting normal organ or tissue. The limiting normal tissue is often the red marrow, but it may sometimes be lungs, liver, intestinal tract, or kidneys. Appropriate treatment planning requires assessment of radiation dose to several internal organs and tissues, and usually involves biodistribution studies in the patient using a tracer amount of radionuclide bound to the targeting agent and imaged at sequential time points using a planar gamma camera. Time-activity curves are developed from the imaging data for the major organs tissues of concern, for the whole body, and sometimes for selected tumors. Patient-specific factors often require that dose estimates be customized for each patient. The Food and Drug Administration regulates the experimental use of investigational new drugs and requires reasonable calculation of radiation absorbed dose to the whole body and to critical organs using methods prescribed by the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. Review of high-dose studies in the U.S. and elsewhere shows that (1) some studies are conducted with minimal dosimetry, (2) the marrow dose is difficult to establish and is subject to large uncertainties, and (3) despite the general availability of MIRD software, internal dosimetry methods are often inconsistent from one clinical center to another

  14. Stochastic cellular automata model and Monte Carlo simulations of CD4+ T cell dynamics with a proposed alternative leukapheresis treatment for HIV/AIDS.

    Science.gov (United States)

    Precharattana, Monamorn; Nokkeaw, Arthorn; Triampo, Wannapong; Triampo, Darapond; Lenbury, Yongwimon

    2011-07-01

    Acquired Immunodeficiency Syndrome (AIDS) is responsible for millions of deaths worldwide. To date, many drug treatment regimens have been applied to AIDS patients but none has resulted in a successful cure. This is mainly due to the fact that free HIV particles are frequently in mutation, and infected CD4(+) T cells normally reside in the lymphoid tissue where they cannot (so far) be eradicated. We present a stochastic cellular automaton (CA) model to computationally study what could be an alternative treatment, namely Leukapheresis (LCAP), to remove HIV infected leukocytes in the lymphoid tissue. We base our investigations on Monte Carlo computer simulations. Our major objective is to investigate how the number of infected CD4(+) T cells changes in response to LCAP during the short-time (weeks) and long-time (years) scales of HIV/AIDS progression in an infected individual. To achieve our goal, we analyze the time evolution of the CD4(+) T cell population in the lymphoid tissue (i.e., the lymph node) for HIV dynamics in treatment situations with various starting times and frequencies and under a no treatment condition. Our findings suggest that the effectiveness of the treatment depends mainly on the treatment starting time and the frequency of the LCAP. Other factors (e.g., the removal proportion, the treatment duration, and the state of removed cells) that likely influence disease progression are subjects for further investigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Monte Carlo methods

    CERN Document Server

    Kalos, Melvin H

    2008-01-01

    This introduction to Monte Carlo methods seeks to identify and study the unifying elements that underlie their effective application. Initial chapters provide a short treatment of the probability and statistics needed as background, enabling those without experience in Monte Carlo techniques to apply these ideas to their research.The book focuses on two basic themes: The first is the importance of random walks as they occur both in natural stochastic systems and in their relationship to integral and differential equations. The second theme is that of variance reduction in general and importance sampling in particular as a technique for efficient use of the methods. Random walks are introduced with an elementary example in which the modeling of radiation transport arises directly from a schematic probabilistic description of the interaction of radiation with matter. Building on this example, the relationship between random walks and integral equations is outlined

  16. Automated planning of ablation targets in atrial fibrillation treatment

    Science.gov (United States)

    Keustermans, Johannes; De Buck, Stijn; Heidbüchel, Hein; Suetens, Paul

    2011-03-01

    Catheter based radio-frequency ablation is used as an invasive treatment of atrial fibrillation. This procedure is often guided by the use of 3D anatomical models obtained from CT, MRI or rotational angiography. During the intervention the operator accurately guides the catheter to prespecified target ablation lines. The planning stage, however, can be time consuming and operator dependent which is suboptimal both from a cost and health perspective. Therefore, we present a novel statistical model-based algorithm for locating ablation targets from 3D rotational angiography images. Based on a training data set of 20 patients, consisting of 3D rotational angiography images with 30 manually indicated ablation points, a statistical local appearance and shape model is built. The local appearance model is based on local image descriptors to capture the intensity patterns around each ablation point. The local shape model is constructed by embedding the ablation points in an undirected graph and imposing that each ablation point only interacts with its neighbors. Identifying the ablation points on a new 3D rotational angiography image is performed by proposing a set of possible candidate locations for each ablation point, as such, converting the problem into a labeling problem. The algorithm is validated using a leave-one-out-approach on the training data set, by computing the distance between the ablation lines obtained by the algorithm and the manually identified ablation points. The distance error is equal to 3.8+/-2.9 mm. As ablation lesion size is around 5-7 mm, automated planning of ablation targets by the presented approach is sufficiently accurate.

  17. Advances in Monte-Carlo code TRIPOLI-4®’s treatment of the electromagnetic cascade

    Directory of Open Access Journals (Sweden)

    Mancusi Davide

    2018-01-01

    Full Text Available TRIPOLI-4® is a Monte-Carlo particle-transport code developed at CEA-Saclay (France that is employed in the domains of nuclear-reactor physics, criticality-safety, shielding/radiation protection and nuclear instrumentation. The goal of this paper is to report on current developments, validation and verification made in TRIPOLI-4 in the electron/positron/photon sector. The new capabilities and improvements concern refinements to the electron transport algorithm, the introduction of a charge-deposition score, the new thick-target bremsstrahlung option, the upgrade of the bremsstrahlung model and the improvement of electron angular straggling at low energy. The importance of each of the developments above is illustrated by comparisons with calculations performed with other codes and with experimental data.

  18. PyCMSXiO: an external interface to script treatment plans for the Elekta® CMS XiO treatment planning system

    International Nuclear Information System (INIS)

    Xing, Aitang; Arumugam, Sankar; Holloway, Lois; Goozee, Gary

    2014-01-01

    Scripting in radiotherapy treatment planning systems not only simplifies routine planning tasks but can also be used for clinical research. Treatment planning scripting can only be utilized in a system that has a built-in scripting interface. Among the commercially available treatment planning systems, Pinnacle (Philips) and Raystation (Raysearch Lab.) have inherent scripting functionality. CMS XiO (Elekta) is a widely used treatment planning system in radiotherapy centres around the world, but it does not have an interface that allows the user to script radiotherapy plans. In this study an external scripting interface, PyCMSXiO, was developed for XiO using the Python programming language. The interface was implemented as a python package/library using a modern object-oriented programming methodology. The package was organized as a hierarchy of different classes (objects). Each class (object) corresponds to a plan object such as the beam of a clinical radiotherapy plan. The interface of classes was implemented as object functions. Scripting in XiO using PyCMSXiO is comparable with Pinnacle scripting. This scripting package has been used in several research projects including commissioning of a beam model, independent three-dimensional dose verification for IMRT plans and a setup-uncertainty study. Ease of use and high-level functions provided in the package achieve a useful research tool. It was released as an open-source tool that may benefit the medical physics community.

  19. Evaluation of superficial dosimetry between treatment planning system and measurement for several breast cancer treatment techniques

    Energy Technology Data Exchange (ETDEWEB)

    Akino, Yuichi; Das, Indra J.; Bartlett, Gregory K.; Zhang Hualin; Thompson, Elizabeth; Zook, Jennifer E. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States) and Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871 (Japan); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202 (United States)

    2013-01-15

    Purpose: Dosimetric accuracy in radiation treatment of breast cancer is critical for the evaluation of cosmetic outcomes and survival. It is often considered that treatment planning systems (TPS) may not be able to provide accurate dosimetry in the buildup region. This was investigated in various treatment techniques such as tangential wedges, field-in-field (FF), electronic compensator (eComp), and intensity-modulated radiotherapy (IMRT). Methods: Under Institutional Review Board (IRB) exemption, radiotherapy treatment plans of 111 cases were retrospectively analyzed. The distance between skin surface and 95% isodose line was measured. For measurements, Gafchromic EBT2 films were used on a humanoid unsliced phantom. Multiple layers of variable thickness of superflab bolus were placed on the breast phantom and CT scanned for planning. Treatment plans were generated using four techniques with two different grid sizes (1 Multiplication-Sign 1 and 2.5 Multiplication-Sign 2.5 mm{sup 2}) to provide optimum dose distribution. Films were placed at different depths and exposed with the selected techniques. A calibration curve for dose versus pixel values was also generated on the same day as the phantom measurement was conducted. The DICOM RT image, dose, and plan data were imported to the in-house software. On axial plane of CT slices, curves were drawn at the position where EBT2 films were placed, and the dose profiles on the lines were acquired. The calculated and measured dose profiles were separated by check points which were marked on the films before irradiation. The segments of calculated profiles were stretched to match their resolutions to that of film dosimetry. Results: On review of treatment plans, the distance between skin and 95% prescribed dose was up to 8 mm for plans of 27 patients. The film measurement revealed that the medial region of phantom surface received a mere 45%-50% of prescribed dose. For wedges, FF, and eComp techniques, region around the

  20. SPIDERplan: A tool to support decision-making in radiation therapy treatment plan assessment.

    Science.gov (United States)

    Ventura, Tiago; Lopes, Maria do Carmo; Ferreira, Brigida Costa; Khouri, Leila

    2016-01-01

    In this work, a graphical method for radiotherapy treatment plan assessment and comparison, named SPIDERplan, is proposed. It aims to support plan approval allowing independent and consistent comparisons of different treatment techniques, algorithms or treatment planning systems. Optimized plans from modern radiotherapy are not easy to evaluate and compare because of their inherent multicriterial nature. The clinical decision on the best treatment plan is mostly based on subjective options. SPIDERplan combines a graphical analysis with a scoring index. Customized radar plots based on the categorization of structures into groups and on the determination of individual structures scores are generated. To each group and structure, an angular amplitude is assigned expressing the clinical importance defined by the radiation oncologist. Completing the graphical evaluation, a global plan score, based on the structures score and their clinical weights, is determined. After a necessary clinical validation of the group weights, SPIDERplan efficacy, to compare and rank different plans, was tested through a planning exercise where plans had been generated for a nasal cavity case using different treatment planning systems. SPIDERplan method was applied to the dose metrics achieved by the nasal cavity test plans. The generated diagrams and scores successfully ranked the plans according to the prescribed dose objectives and constraints and the radiation oncologist priorities, after a necessary clinical validation process. SPIDERplan enables a fast and consistent evaluation of plan quality considering all targets and organs at risk.

  1. Treatment planning and dosimetry in radiotherapy for glottic cancer

    International Nuclear Information System (INIS)

    Fukudomi, Yukimi; Kawakami, Toshiaki; Fujii, Takashi; Kawamura, Masashi; Kataoka, Masaaki; Hamamoto, Ken

    1995-01-01

    To perform a precise radiotherapy and to prevent local failure as low as possible for early glottic cancer, we present data regarding the technical basis of radiotherapy. Thermoluminescent dosimeters (TLDs) were embedded at 6 locations in a hand-made Mix-Dp phantom and exposed to two lateral-opposed beams using 6 x 6 cm 2 fields. The dosimeters were irradiated using 4 MV-X, 6 MV-X and 10 MV-X with open-field, 15deg and 30deg wedge filter (WF) made of Pb or Fe, and a hand-made Mix-Dp WF compensating irregular skin surface which was placed apart from the patient's skin to preserve skin-sparing properties. Calculation of absorbed dose with a computer for treatment planning was performed. Using 6 MV-X and a 30deg WF, the dose distribution was the best in this phantom. With 10 MV-X, the absorbed dose at the anterior glottis was 6.7-11.6% lower than the administered dose. Using a Mix-Dp WF, the dose distribution was better than those using WF made of Pb or Fe. Under various types of treatments, the absorbed dose at the reference point using TLDs were 0.4-5.8% lower than the administered dose calculated with ratio-TAR method at the same point. These are believed to be due to lack of estimation of scatters and poor correcting method for WF factor. We conclude that some experimental checks are desirable to perform a precise radiotherapy for laryngeal cancer. This can be done using a number of TLDs placed at points of interest in a phantom. (author)

  2. On the quality of treatment planning systems in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Panten, T.; Sroka-Perez, G. [Radiologische Klinik der Univ. Heidelberg, Heidelberg (Germany). Abt. fuer Klinische Radiologie; Hoess, A. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Abt. Medizinische Physik; Bohsung, J. [Humboldt-Universitaet, Berlin (Germany). Abt. fuer Strahlentherapie; Becker, G. [Radiologische Universitaetsklinik, Tuebingen (Germany). Abt. fuer Strahlentherapie

    1998-10-01

    Purpose: To assist in the design of quality assurance activities of 3D treatment planning systems (TPSs), a postal survey has been carried out, addressing TPS users on quality characteristics and their relative importance in clinical routine planning. Material and methods: The approach as described in ISO/IEC 9126 has been used to analyze TPS quality. Both TPS quality characteristics and how these may be used to establish a quality model are included. A questionnaire on ranking of these TPS quality characteristics has been sent out to the German DEGRO members in February 1997. Results: By the end of July 1997, 90 individual assessments (of 45 physicists, 35 physicians, and 10 radiographers) had been collected. On an importance scale from 1 (very important) to 6 (unimportant), weight factors of 1.71 (portability), 2.84 (maintainability), 3.18 (efficiency), 3.85 (usability), 4.52 (functionality) and 4.90 (reliability) have been determined from the data. From user satisfaction data also obtained from the questionnaire responses, baseline quality indices could be established from the quality model for the RTPs Cadplan, TMS Helax, and Voxelplan. Conclusion: The responses highlight the need for TPS quality assurance at the same time along the lines of safety-related, research-oriented, and interactive end-user software systems in radiotherapy treatment planning. Quality assurance activities must take this into account. Their effect can be monitored by using quality indices as derivable from the established quality model. (orig.) [Deutsch] Ziel: Um die Planung von Qualitaetssicherungsmassnahmen an 3D-Bestrahlungsplanungssystemen (BPS) zu unterstuetzen, wurde eine postalische Umfrage unter BPS-Anwendern bezueglich der Qualitaetsmerkmale und deren relativer Wichtigkeit durchgefuehrt. Material und Methoden: Zur Analyse der Qualitaet von BPS wurde die Herangehensweise nach ISO/IEC 9126 benutzt, die sowohl die BPS-Qualitaetsmerkmale als auch ein Verfahren zu deren Verknuepfung

  3. SNF sludge treatment system preliminary project execution plan

    International Nuclear Information System (INIS)

    Flament, T.A.

    1998-01-01

    The Fluor Daniel Hanford, Inc. (FDH) Project Director for the Spent Nuclear Fuel (SNF) Project has requested Numatec Hanford Company (NHC) to define how Hanford would manage a new subproject to provide a process system to receive and chemically treat radioactive sludge currently stored in the 100 K Area fuel retention basins. The subproject, named the Sludge Treatment System (STS) Subproject, provides and operates facilities and equipment to chemically process K Basin sludge to meet Tank Waste Remediation System (TWRS) requirements. This document sets forth the NHC management approach for the STS Subproject and will comply with the requirements of the SNF Project Management Plan (HNF-SD-SNFPMP-011). This version of this document is intended to apply to the initial phase of the subproject and to evolve through subsequent revision to include all design, fabrication, and construction conducted on the project and the necessary management and engineering functions within the scope of the subproject. As Project Manager, NHC will perform those activities necessary to complete the STS Subproject within approved cost and schedule baselines and turn over to FDH facilities, systems, and documentation necessary for operation of the STS

  4. Inverse treatment planning using volume-based objective functions

    Science.gov (United States)

    Bednarz, Greg; Michalski, Darek; Anne, Pramila R.; Valicenti, Richard K.

    2004-06-01

    The results of optimization of inverse treatment plans depend on a choice of the objective function. Even when the optimal solution for a given cost function can be obtained, a better solution may exist for a given clinical scenario and it could be obtained with a revised objective function. In the approach presented in this work mixed integer programming was used to introduce a new volume-based objective function, which allowed for minimization of the number of under- or overdosed voxels in selected structures. By selecting and prioritizing components of this function the user could drive the computations towards the desired solution. This optimization approach was tested using cases of patients treated for prostate and oropharyngeal cancer. Initial solutions were obtained based on minimization/maximization of the dose to critical structures and targets. Subsequently, the volume-based objective functions were used to locate solutions, which satisfied better clinical objectives particular to each of the cases. For prostate cases, these additional solutions offered further improvements in sparing of the rectum or the bladder. For oropharyngeal cases, families of solutions were obtained satisfying an intensity modulated radiation therapy protocol for this disease site, while offering significant improvement in the sparing of selected critical structures, e.g., parotid glands. An additional advantage of the present approach was in providing a convenient mechanism to test the feasibility of the dose-volume histogram constraints.

  5. Film dosimetry of small elongated electron beams for treatment planning

    International Nuclear Information System (INIS)

    Niroomand-Rad, A.

    1989-01-01

    The characteristics of 5, 7, 10, 12, 15, and 18 Mev electron beams for small elongated fields of dimensions L x W (where L=1, 2, 3, 4, 5, and 10 cm; and W=1, 2, 3, 4, 5, and 10 cm) have been studied. Film dosimetry and parallel-plate ion chamber measurements have been used to obtain various dose parameters. Selective results of a series of systematic measurements for central axis depth dose data, uniformity index, field flatness, and relative output factors of small elongated electron beams are reported. The square-root method is employed to predict the beam data of small elongated electron fields from corresponding small square electron fields using film dosimetry. The single parameter area/perimeter radio A/P is used to characterize the relative output factors of elongated electron beams. It is our conclusion that for clinical treatment planning square-root method may be applied with caution in determining the beam characteristics of small elongated electron fields from film dosimetry. The calculated and estimated relative output factors from square-root method and A/P ratio are in good agreement and show agreement to within 1% with the measured film values

  6. Paradoxical embolism: role of imaging in diagnosis and treatment planning.

    Science.gov (United States)

    Saremi, Farhood; Emmanuel, Neelmini; Wu, Phil F; Wu, Philip F; Ihde, Lauren; Shavelle, David; Go, John L; Sánchez-Quintana, Damián

    2014-10-01

    Paradoxical embolism (PDE) is an uncommon cause of acute arterial occlusion that may have catastrophic sequelae. The possibility of its presence should be considered in all patients with an arterial embolus in the absence of a cardiac or proximal arterial source. Despite advancements in radiologic imaging technology, the use of various complementary modalities is usually necessary to exclude other possibilities from the differential diagnosis and achieve an accurate imaging-based diagnosis of PDE. In current practice, the imaging workup of a patient with symptoms of PDE usually starts with computed tomography (CT) and magnetic resonance (MR) imaging to identify the cause of the symptoms and any thromboembolic complications in target organs (eg, stroke, peripheral arterial occlusion, or visceral organ ischemia). Additional imaging studies with modalities such as peripheral venous Doppler ultrasonography (US), transcranial Doppler US, echocardiography, and CT or MR imaging are required to detect peripheral and central sources of embolism, identify cardiac and/or extracardiac shunts, and determine whether arterial disease is present. To guide radiologists in selecting the optimal modalities for use in various diagnostic settings, the article provides detailed information about the imaging of PDE, with numerous radiologic and pathologic images illustrating the wide variety of features that may accompany and contribute to the pathologic process. The roles of CT and MR imaging in the diagnosis and exclusion of PDE are described, and the use of imaging for planning surgical treatment and interventional procedures is discussed.

  7. SU-F-T-217: A Comprehensive Monte-Carlo Study of Out-Of-Field Secondary Neutron Spectra in a Scanned-Beam Proton Therapy Treatment Room

    Energy Technology Data Exchange (ETDEWEB)

    Englbrecht, F; Parodi, K [LMU Munich, Department of Medical Physics, Garching / Munich, Bavaria (Germany); Trinkl, S; Mares, V; Ruehm, W; Wielunski, M [Helmholtz Zentrum Munich, Institute of Radiation Protection, Neuherberg, Bavaria (Germany); Wilkens, J [Technical University of Munich, Department of Physics, Munich, Germany, Garching, Bavaria (Germany); Klinikum rechts der Isar, Department of Radiation Oncology, Munich (Germany); Hillbrand, M [Rinecker Proton Therapy Center, Munich, Bavaria (Germany)

    2016-06-15

    Purpose: To simulate secondary neutron radiation-fields produced at different positions during phantom irradiation inside a scanning proton therapy gantry treatment room. Further, to identify origin, energy distribution and angular emission as function of proton beam energy. Methods: GEANT4 and FLUKA Monte-Carlo codes were used to model the relevant parts of the treatment room in a gantry-equipped pencil beam scanning proton therapy facility including walls, floor, metallic gantry-components, patient table and the homogeneous PMMA target. The proton beams were modeled based on experimental beam ranges in water and spot shapes in air. Neutron energy spectra were simulated at 0°, 45°, 90° and 135° relative to the beam axis at 2m distance from isocenter, as well as 11×11 cm2 fields for 75MeV, 140MeV, 200MeV and for 118MeV with 5cm PMMA range-shifter. The total neutron energy distribution was recorded for these four positions and proton energies. Additionally, the room-components generating secondary neutrons in the room and their contributions to the total spectrum were identified and quantified. Results: FLUKA and GEANT4 simulated neutron spectra showed good general agreement in the whole energy range of 10{sup −}9 to 10{sup 2} MeV. Comparison of measured spectra with the simulated contributions of the various room components helped to limit the complexity of the room model, by identifying the dominant contributions to the secondary neutron spectrum. The iron of the bending magnet and counterweight were identified as sources of secondary evaporation-neutrons, which were lacking in simplified room models. Conclusion: Thorough Monte-Carlo simulations have been performed to complement Bonner-sphere spectrometry measurements of secondary neutrons in a clinical proton therapy treatment room. Such calculations helped disentangling the origin of secondary neutrons and their dominant contributions to measured spectra, besides providing a useful validation of widely

  8. Realizing a new paradigm in radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Ziegenhein, Peter

    2013-01-01

    This thesis investigates the feasibility of a new IMRT planning paradigm called Interactive Dose Shaping (IDS). The IDS paradigm enables the therapist to directly impose local dose features into the therapy plan. In contrast to the conventional IMRT planning approach, IDS does not employ an objective function to drive an iterative optimization procedure. In the first part of this work, the conventional IMRT plan optimization method is investigated. Concepts for a near-optimal implementation of the planning problem are provided. The second part of this work introduces the IDS concept. It is designed to overcome clinical drawbacks of the conventional method on the one hand and to provide interactive planning strategies which exploit the full potential of modern high-performance computer hardware on the other hand. The realization of the IDS concept consists of three main parts. (1)A two-step Dose Variation and Recovery (DVR) strategy which imposes localized plan features and recovers for unintentional plan modifications elsewhere. (2)A new dose calculation method (3)The design of an IDS planning framework which provides a powerful graphical user interface. It could be shown that the IDS paradigm is able to reproduce conventionally optimized therapy plans and that the IDS concepts can be realized in real-time.

  9. 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

  10. Analysis of Radiation Treatment Planning by Dose Calculation and Optimization Algorithm

    International Nuclear Information System (INIS)

    Kim, Dae Sup; Yoon, In Ha; Lee, Woo Seok; Baek, Geum Mun

    2012-01-01

    Analyze the Effectiveness of Radiation Treatment Planning by dose calculation and optimization algorithm, apply consideration of actual treatment planning, and then suggest the best way to treatment planning protocol. The treatment planning system use Eclipse 10.0. (Varian, USA). PBC (Pencil Beam Convolution) and AAA (Anisotropic Analytical Algorithm) Apply to Dose calculation, DVO (Dose Volume Optimizer 10.0.28) used for optimized algorithm of Intensity Modulated Radiation Therapy (IMRT), PRO II (Progressive Resolution Optimizer V 8.9.17) and PRO III (Progressive Resolution Optimizer V 10.0.28) used for optimized algorithm of VAMT. A phantom for experiment virtually created at treatment planning system, 30x30x30 cm sized, homogeneous density (HU: 0) and heterogeneous density that inserted air assumed material (HU: -1,000). Apply to clinical treatment planning on the basis of general treatment planning feature analyzed with Phantom planning. In homogeneous density phantom, PBC and AAA show 65.2% PDD (6 MV, 10 cm) both, In heterogeneous density phantom, also show similar PDD value before meet with low density material, but they show different dose curve in air territory, PDD 10 cm showed 75%, 73% each after penetrate phantom. 3D treatment plan in same MU, AAA treatment planning shows low dose at Lung included area. 2D POP treatment plan with 15 MV of cervical vertebral region include trachea and lung area, Conformity Index (ICRU 62) is 0.95 in PBC calculation and 0.93 in AAA. DVO DVH and Dose calculation DVH are showed equal value in IMRT treatment plan. But AAA calculation shows lack of dose compared with DVO result which is satisfactory condition. Optimizing VMAT treatment plans using PRO II obtained results were satisfactory, but lower density area showed lack of dose in dose calculations. PRO III, but optimizing the dose calculation results were similar with optimized the same conditions once more. In this study, do not judge the rightness of the dose

  11. Analysis of Radiation Treatment Planning by Dose Calculation and Optimization Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Sup; Yoon, In Ha; Lee, Woo Seok; Baek, Geum Mun [Dept. of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of)

    2012-09-15

    Analyze the Effectiveness of Radiation Treatment Planning by dose calculation and optimization algorithm, apply consideration of actual treatment planning, and then suggest the best way to treatment planning protocol. The treatment planning system use Eclipse 10.0. (Varian, USA). PBC (Pencil Beam Convolution) and AAA (Anisotropic Analytical Algorithm) Apply to Dose calculation, DVO (Dose Volume Optimizer 10.0.28) used for optimized algorithm of Intensity Modulated Radiation Therapy (IMRT), PRO II (Progressive Resolution Optimizer V 8.9.17) and PRO III (Progressive Resolution Optimizer V 10.0.28) used for optimized algorithm of VAMT. A phantom for experiment virtually created at treatment planning system, 30x30x30 cm sized, homogeneous density (HU: 0) and heterogeneous density that inserted air assumed material (HU: -1,000). Apply to clinical treatment planning on the basis of general treatment planning feature analyzed with Phantom planning. In homogeneous density phantom, PBC and AAA show 65.2% PDD (6 MV, 10 cm) both, In heterogeneous density phantom, also show similar PDD value before meet with low density material, but they show different dose curve in air territory, PDD 10 cm showed 75%, 73% each after penetrate phantom. 3D treatment plan in same MU, AAA treatment planning shows low dose at Lung included area. 2D POP treatment plan with 15 MV of cervical vertebral region include trachea and lung area, Conformity Index (ICRU 62) is 0.95 in PBC calculation and 0.93 in AAA. DVO DVH and Dose calculation DVH are showed equal value in IMRT treatment plan. But AAA calculation shows lack of dose compared with DVO result which is satisfactory condition. Optimizing VMAT treatment plans using PRO II obtained results were satisfactory, but lower density area showed lack of dose in dose calculations. PRO III, but optimizing the dose calculation results were similar with optimized the same conditions once more. In this study, do not judge the rightness of the dose

  12. Monte Carlo simulations for dose enhancement in cancer treatment using bismuth oxide nanoparticles implanted in brain soft tissue.

    Science.gov (United States)

    Taha, Eslam; Djouider, Fathi; Banoqitah, Essam

    2018-03-26

    The objective of this work is to study the dosimetric performances of bismuth oxide nanoparticles implanted in tumors in cancer radiotherapy. GEANT4 based Monte Carlo numerical simulations were performed to assess dose enhancement distributions in and around a 1 × 1 × 1 cm 3 tumor implanted with different concentrations of bismuth oxide and irradiated with low energies 125 I, 131 Cs, and 103 Pd radioactive sources. Dose contributions were considered from photoelectrons, Auger electrons, and characteristic X-rays. Our results show the dose enhancement increased with increasing both bismuth oxide concentration in the target and photon energy. A dose enhancement factor up to 18.55 was obtained for a concentration of 70 mg/g of bismuth oxide in the tumor when irradiated with 131 Cs source. This study showed that bismuth oxide nanoparticles are innovative agents that could be potentially applicable to in vivo cancer radiotherapy due to the fact that they induce a highly localized energy deposition within the tumor.

  13. Technical Note: Is bulk electron density assignment appropriate for MRI-only based treatment planning for lung cancer?

    Science.gov (United States)

    Prior, Phil; Chen, Xinfeng; Gore, Elizabeth; Johnstone, Candice; Li, X Allen

    2017-07-01

    MRI-based treatment planning in radiation therapy (RT) is prohibitive, in part, due to the lack of electron density (ED) information within the image. The dosimetric differences between MRI- and CT-based planning for intensity modulated RT (IMRT) of lung cancer were investigated to assess the appropriateness of bulk ED assignment. Planning CTs acquired for six representative lung cancer patients were used to generate bulk ED IMRT plans. To avoid the effect of anatomic differences between CT and MRI, "simulated MRI-based plans" were generated by forcing the relative ED (rED) to water on CT-delineated structures using organ specific values from the ICRU Report 46 and using the mean rED value of the internal target volume (ITV) from the planning CT. The "simulated MRI-based plans" were generated using a research planning system (Monaco v5.09.07a, Elekta, AB) and employing Monte Carlo dose calculation. The following dose-volume-parameters (DVPs) were collected from both the "simulated MRI-based plans" and the original planning CT: D 95 , the dose delivered to 95% of the ITV & planning target volume (PTV), D 5 and V 5 , the volume of normal lung irradiated ≥5 Gy. The percent point difference and relative dose difference were used for comparison with the CT based plan for V 5 and D 95 respectively. A total of five plans per patient were generated; three with the ITV rED (rED ITV ) = 1.06, 1.0 and the mean value from the planning CT while the lung rED (rED lung ) was fixed at the ICRU value of 0.26 and two with rED lung = 0.1 and 0.5 while the rED ITV was fixed to the mean value from the planning CT. Noticeable differences in the ITV and PTV DVPs were observed. Variations of the normal lung V 5 can be as large as 9.6%. In some instances, varying the rED ITV between rED mean and 1.06 resulted in D 95 increases ranging from 3.9% to 6.3%. Bulk rED assignment on normal lung affected the DVPs of the ITV and PTV by 4.0-9.8% and 0.3-19.6% respectively. Dose volume histograms

  14. Monte Carlo simulations for the design of the treatment rooms and synchrotron access mazes in the CNAO hadron-therapy facility

    International Nuclear Information System (INIS)

    Porta, A.; Agosteo, S.; Campi, F.

    2005-01-01

    The Italian National Centre for Hadron-therapy is based on a synchrotron capable of accelerating protons and carbon ions up to 250 MeV and 400 MeV u -1 , respectively. The present work describes some Monte Carlo simulations performed to verify the design of the treatment rooms and synchrotron access mazes. The different shielding efficiency and induced activations of the common concrete and the baryte concrete were analysed. In such a radiation field, i.e. with high-energy neutrons, the baryte concrete gains twice the activation than the common concrete without any relevant dose reduction. Moreover, the simulations have stressed, again, the discrepancies between H*(10) and E in such cases where the neutron radiation field is the dominant component and, particularly, in the medium-high energy range. (authors)

  15. Functional anatomy of the prostate: Implications for treatment planning

    International Nuclear Information System (INIS)

    McLaughlin, Patrick W.; Troyer, Sara; Berri, Sally; Narayana, Vrinda; Meirowitz, Amichay; Roberson, Peter L.; Montie, James

    2005-01-01

    Purpose: To summarize the functional anatomy relevant to prostate cancer treatment planning. Methods and Materials: Coronal, axial, and sagittal T2 magnetic resonance imaging (MRI) and MRI angiography were fused by mutual information and registered with computed tomography (CT) scan data sets to improve definition of zonal anatomy of the prostate and critical adjacent structures. Results: The three major prostate zones (inner, outer, and anterior fibromuscular) are visible by T2 MRI imaging. The bladder, bladder neck, and internal (preprostatic) sphincter are a continuous muscular structure and clear definition of the preprostatic sphincter is difficult by MRI. Transition zone hypertrophy may efface the bladder neck and internal sphincter. The external 'lower' sphincter is clearly visible by T2 MRI with wide variations in length. The critical erectile structures are the internal pudendal artery (defined by MRI angiogram or T2 MRI), corpus cavernosum, and neurovascular bundle. The neurovascular bundle is visible along the posterior lateral surface of the prostate on CT and MRI, but its terminal branches (cavernosal nerves) are not visible and must be defined by their relationship to the urethra within the genitourinary diaphragm. Visualization of the ejaculatory ducts within the prostate is possible on sagittal MRI. The anatomy of the prostate-rectum interface is clarified by MRI, as is the potentially important distinction of rectal muscle and rectal mucosa. Conclusion: Improved understanding of functional anatomy and imaging of the prostate and critical adjacent structures will improve prostate radiation therapy by improvement of dose and toxicity correlation, limitation of dose to critical structures, and potential improvement in post therapy quality of life

  16. Assessment and treatment of planning skills in adolescents with ADHD

    NARCIS (Netherlands)

    Boyer, B.E.

    2016-01-01

    Planning problems are described to be prominent in the daily lives of adolescents with ADHD (Barkley, 2004) and may cause comorbid conditions and impairments (Safren, 2006). Therefore the central aim of this thesis was to assess planning skills of adolescents with ADHD and to investigate whether

  17. Treatment planning for heavy ion irradiation. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Jaekel, O. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). FS Radiologische Diagnostik und Therapie; Kraemer, M. [Gesellschaft fuer Schwerionenforschung (GSI), Biophysik, Darmstadt (Germany)

    1997-09-01

    In this contribution we will outline briefly the GSI beam delivery system and the qualitative differences in the methods used for inverse planning arising from it. We will describe the planning package, consisting of VOXELPLAN and TRiP and show some results for first test cases. (orig./MG)

  18. Manpower Planning for Municipal Wastewater Treatment in Texas, LP-8.

    Science.gov (United States)

    Texas State Dept. of Water Resources, Austin.

    This report presents the implementation results of a pilot test of a manpower planning methodology developed by the U.S. Environmental Protection Agency (EPA), Office of Water Programs. Project outputs and projections are described and illustrated in sections of the report dealing with work to be done, organizational staffing plan, transfers and…

  19. 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

  20. Scanned ion beam therapy for prostate carcinoma. Comparison of single plan treatment and daily plan-adapted treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hild, Sebastian [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Department of Biophysics, Darmstadt (Germany); University Clinic Erlangen and Friedrich- Alexander-University Erlangen-Nuernberg (FAU), Department of Radiation Oncology, Erlangen (Germany); Graeff, Christian [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Department of Biophysics, Darmstadt (Germany); Rucinski, Antoni [University Clinic Heidelberg, Heidelberg Ion-Beam Therapy Center (HIT) and Department of Radiation Oncology, Heidelberg (Germany); Sapienza Universit' a di Roma, Dipartimento di Scienze di Base e Applicate per Ingegneria, Roma (Italy); INFN, Roma (Italy); Zink, Klemens [University of Applied Sciences, Institute for Medical Physics and Radiation Protection, Giessen (Germany); University Medical Center Giessen-Marburg, Department of Radiotherapy and Radiooncology, Marburg (Germany); Habl, Gregor [University Clinic Heidelberg, Heidelberg Ion-Beam Therapy Center (HIT) and Department of Radiation Oncology, Heidelberg (Germany); Klinikum rechts der Isar, Technische Universitaet Muenchen (TUM), Department of Radiation Oncology, Munich (Germany); Durante, Marco [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Department of Biophysics, Darmstadt (Germany); Technische Universitaet Darmstadt, Faculty of Physics, Darmstadt (Germany); Herfarth, Klaus [University Clinic Heidelberg, Heidelberg Ion-Beam Therapy Center (HIT) and Department of Radiation Oncology, Heidelberg (Germany); Bert, Christoph [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Department of Biophysics, Darmstadt (Germany); University Clinic Erlangen and Friedrich- Alexander-University Erlangen-Nuernberg (FAU), Department of Radiation Oncology, Erlangen (Germany); University Hospital Erlangen, Radiation Oncology, Erlangen (Germany)

    2016-02-15

    Intensity-modulated particle therapy (IMPT) for tumors showing interfraction motion is a topic of current research. The purpose of this work is to compare three treatment strategies for IMPT to determine potential advantages and disadvantages of ion prostate cancer therapy. Simulations for three treatment strategies, conventional one-plan radiotherapy (ConvRT), image-guided radiotherapy (IGRT), and online adaptive radiotherapy (ART) were performed employing a dataset of 10 prostate cancer patients with six CT scans taken at one week intervals. The simulation results, using a geometric margin concept (7-2 mm) as well as patient-specific internal target volume definitions for IMPT were analyzed by target coverage and exposure of critical structures on single fraction dose distributions. All strategies led to clinically acceptable target coverage in patients exhibiting small prostate motion (mean displacement < 4 mm), but IGRT and especially ART led to significant sparing of the rectum. In 20 % of the patients, prostate motion exceeded 4 mm causing insufficient target coverage for ConvRT (V95{sub mean} = 0.86, range 0.63-0.99) and IGRT (V95{sub mean} = 0.91, range 0.68-1.00), while ART maintained acceptable target coverage. IMPT of prostate cancer demands consideration of rectal sparing and adaptive treatment replanning for patients exhibiting large prostate motion. (orig.) [German] Adaptive Therapieansaetze fuer sich interfraktionell bewegende Zielvolumina in der intensitaetsmodulierten Partikeltherapie (IMPT) befinden sich zurzeit in der Entwicklung. In dieser Arbeit werden drei Behandlungsstrategien auf moegliche Vor- und Nachteile in der IMPT des Prostatakarzinoms hin untersucht. Auf Basis eines anonymisierten Datensatzes aus 10 Patienten mit Prostatakarzinom wurden die drei Bestrahlungsstrategien, konventionelle Ein-Plan-Strahlentherapie (ConvRT), bildunterstuetzte Strahlentherapie (IGRT) und tagesaktuelle Strahlentherapie (adaptive radiotherapy,ART), simuliert

  1. A dosimetric comparison of four treatment planning methods for high grade glioma

    Directory of Open Access Journals (Sweden)

    Miller Robert W

    2009-10-01

    Full Text Available Abstract Background High grade gliomas (HGG are typically treated with a combination of surgery, radiotherapy and chemotherapy. Three dimensional (3D conformal radiotherapy treatment planning is still the main stay of treatment for these patients. New treatment planning methods suggest better dose distributions and organ sparing but their clinical benefit is unclear. The purpose of the current study was to compare normal tissue sparing and tumor coverage using four different radiotherapy planning methods in patients with high grade glioma. Methods Three dimensional conformal (3D, sequential boost IMRT, integrated boost (IB IMRT and Tomotherapy (TOMO treatment plans were generated for 20 high grade glioma patients. T1 and T2 MRI abnormalities were used to define GTV and CTV with 2 and 2.5 cm margins to define PTV1 and PTV2 respectively. Results The mean dose to PTV2 but not to PTV1 was less then 95% of the prescribed dose with IB and IMRT plans. The mean doses to the optic chiasm and the ipsilateral globe were highest with 3D plans and least with IB plans. The mean dose to the contralateral globe was highest with TOMO plans. The mean of the integral dose (ID to the brain was least with the IB plan and was lower with IMRT compared to 3D plans. The TOMO plans had the least mean D10 to the normal brain but higher mean D50 and D90 compared to IB and IMRT plans. The mean D10 and D50 but not D90 were significantly lower with the IMRT plans compared to the 3D plans. Conclusion No single treatment planning method was found to be superior to all others and a personalized approach is advised for planning and treating high-grade glioma patients with radiotherapy. Integral dose did not reflect accurately the dose volume histogram (DVH of the normal brain and may not be a good indicator of delayed radiation toxicity.

  2. Therapeutic Applications of Monte Carlo Calculations in Nuclear Medicine

    International Nuclear Information System (INIS)

    Coulot, J

    2003-01-01

    Monte Carlo techniques are involved in many applications in medical physics, and the field of nuclear medicine has seen a great development in the past ten years due to their wider use. Thus, it is of great interest to look at the state of the art in this domain, when improving computer performances allow one to obtain improved results in a dramatically reduced time. The goal of this book is to make, in 15 chapters, an exhaustive review of the use of Monte Carlo techniques in nuclear medicine, also giving key features which are not necessary directly related to the Monte Carlo method, but mandatory for its practical application. As the book deals with therapeutic' nuclear medicine, it focuses on internal dosimetry. After a general introduction on Monte Carlo techniques and their applications in nuclear medicine (dosimetry, imaging and radiation protection), the authors give an overview of internal dosimetry methods (formalism, mathematical phantoms, quantities of interest). Then, some of the more widely used Monte Carlo codes are described, as well as some treatment planning softwares. Some original techniques are also mentioned, such as dosimetry for boron neutron capture synovectomy. It is generally well written, clearly presented, and very well documented. Each chapter gives an overview of each subject, and it is up to the reader to investigate it further using the extensive bibliography provided. Each topic is discussed from a practical point of view, which is of great help for non-experienced readers. For instance, the chapter about mathematical aspects of Monte Carlo particle transport is very clear and helps one to apprehend the philosophy of the method, which is often a difficulty with a more theoretical approach. Each chapter is put in the general (clinical) context, and this allows the reader to keep in mind the intrinsic limitation of each technique involved in dosimetry (for instance activity quantitation). Nevertheless, there are some minor remarks to

  3. SU-E-J-55: Dosimetric Evaluation of Centrally Located Lung Tumors: A Monte Carlo (MC) Study of Lung SBRT Planning

    Energy Technology Data Exchange (ETDEWEB)

    Pokhrel, D; Badkul, R; Jiang, H; Saleh, H; Estes, C; Park, J; Kumar, P; Wang, F [University Kansas Medical Center, Kansas City, KS (United States)

    2014-06-01

    Purpose: To compare dose distributions calculated using the iPlan XVMC algorithm and heterogeneities corrected/uncorrected Pencil Beam (PB-hete/PB-homo) algorithms for SBRT treatments of lung tumors. Methods: Ten patients with centrally located solitary lung tumors were treated using MC-based SBRT to 60Gy in 5 fractions for PTVV100%=95%. ITV was delineated on MIP-images based on 4D-CT scans. PTVs(ITV+5mm margins) ranged from 10.1–106.5cc(mean=48.6cc). MC-SBRT plans were generated with a combination of non-coplanar conformal arcs/beams using iPlan-XVMC-algorithm (BrainLABiPlan ver.4.1.2) for Novalis-TX consisting of HD-MLCs and 6MV-SRS(1000MU/min) mode, following RTOG 0813 dosimetric criteria. For comparison, PB-hete/PB-homo algorithms were used to re-calculate dose distributions using same beam configurations, MLCs/monitor units. Plans were evaluated with isocenter/maximal/mean doses to PTV. Normal lung doses were evaluated with V5/V10/V20 and mean-lung-dose(MLD), excluding PTV. Other OAR doses such as maximal spinal cord/2cc-esophagus/max bronchial tree (BT/maximal heart doses were tabulated. Results: Maximal/mean/isocenter doses to PTV calculated by PB-hete were uniformly larger than MC plans by a factors of 1.09/1.13/1.07, on average, whereas they were consistently lower by PB-homo by a factors of 0.9/0.84/0.9, respectively. The volume covered by 5Gy/10Gy/20Gy isodose-lines of the lung were comparable (average within±3%) when calculated by PB-hete compared to XVMC, but, consistently lower by PB-homo by a factors of 0.90/0.88/0.85, respectively. MLD was higher with PB-hete by 1.05, but, lower by PB-homo by 0.9, on average, compared to XVMC. XVMC max-cord/max-BT/max-heart and 2cc of esophagus doses were comparable to PB-hete; however, PB-homo underestimates by a factors of 0.82/0.89/0.88/0.86, on average, respectively. Conclusion: PB-hete significantly overestimates dose to PTV relative to XVMC -hence underdosing the target. MC is more complex and accurate with

  4. Treatment of Solar Generation in Electric Utility Resource Planning

    Energy Technology Data Exchange (ETDEWEB)

    Sterling, J.; McLaren, J.; Taylor, M.; Cory, K.

    2013-10-01

    Today's utility planners have a different market and economic context than their predecessors, including planning for the growth of renewable energy. State and federal support policies, solar photovoltaic (PV) price declines, and the introduction of new business models for solar PV 'ownership' are leading to increasing interest in solar technologies (especially PV); however, solar introduces myriad new variables into the utility resource planning decision. Most, but not all, utility planners have less experience analyzing solar than conventional generation as part of capacity planning, portfolio evaluation, and resource procurement decisions. To begin to build this knowledge, utility staff expressed interest in one effort: utility exchanges regarding data, methods, challenges, and solutions for incorporating solar in the planning process. Through interviews and a questionnaire, this report aims to begin this exchange of information and capture utility-provided information about: 1) how various utilities approach long-range resource planning; 2) methods and tools utilities use to conduct resource planning; and, 3) how solar technologies are considered in the resource planning process.

  5. Design and implementation of a complementary treatment planning software for the GZP6 high dose rate brachytherapy system (GZP6 CTPS)

    International Nuclear Information System (INIS)

    Hariri Tabrizi, S.; Kamali Asl, A.; Azma, Z.

    2010-01-01

    Brachytherapy is one of the most common treatment modalities for gynecological cancer. The GZP6 brachytherapy system is one of the devices utilized in Iran. It has been considered particularly due to its low cost compared to other more complete and established systems. This system has some deficiencies including lack of a treatment planning software for non-predefined treatments, inability to change the gradually changeable dosimetric variables and using a point source estimation in dose calculation. This report presents a complementary treatment planning software to the system's own dedicated program. Material and Methods:. First, the dosimetric characteristics of three GZP6 sources were calculated based on the TG-43 protocol using the MCNP4C Monte Carlo code. Then, the calculated dose distribution around the implanted applicators, based on the selected dwell positions and dwell times, was shown in a graphical user interface written using the MATLAB software. Results: The computation uncertainty in the resulting TG-43 parameters was about 1% and the calculated parameters were in good agreement with similar studies on cobalt-60 source dosimetry. Furthermore, the graphical user interface is prepared as a user-friendly executable file which can be installed on any operating system. Discussion and Conclusion: Since different patients have distinct anatomy and physical conditions, a program for non-predefined situations of source arrangement is necessary. Using GZP6 complementary treatment planning software can satisfy this requirement.

  6. 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...

  7. Automation of radiation treatment planning. Evaluation of head and neck cancer patient plans created by the Pinnacle{sup 3} scripting and Auto-Planning functions

    Energy Technology Data Exchange (ETDEWEB)

    Speer, Stefan; Weiss, Alexander; Bert, Christoph [Universitaetsklinikum Erlangen, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Department of Radiation Oncology, Erlangen (Germany); Klein, Andreas [EKS Engineering GmbH, Fuerth (Germany); Kober, Lukas [Strahlentherapie Tauber-Franken, Bad Mergentheim (Germany); Yohannes, Indra [Rinecker Proton Therapy Center, Munich (Germany)

    2017-08-15

    Intensity-modulated radiotherapy (IMRT) techniques are now standard practice. IMRT or volumetric-modulated arc therapy (VMAT) allow treatment of the tumor while simultaneously sparing organs at risk. Nevertheless, treatment plan quality still depends on the physicist's individual skills, experiences, and personal preferences. It would therefore be advantageous to automate the planning process. This possibility is offered by the Pinnacle{sup 3} treatment planning system (Philips Healthcare, Hamburg, Germany) via its scripting language or Auto-Planning (AP) module. AP module results were compared to in-house scripts and manually optimized treatment plans for standard head and neck cancer plans. Multiple treatment parameters were scored to judge plan quality (100 points = optimum plan). Patients were initially planned manually by different physicists and re-planned using scripts or AP. Script-based head and neck plans achieved a mean of 67.0 points and were, on average, superior to manually created (59.1 points) and AP plans (62.3 points). Moreover, they are characterized by reproducibility and lower standard deviation of treatment parameters. Even less experienced staff are able to create at least a good starting point for further optimization in a short time. However, for particular plans, experienced planners perform even better than scripts or AP. Experienced-user input is needed when setting up scripts or AP templates for the first time. Moreover, some minor drawbacks exist, such as the increase of monitor units (+35.5% for scripted plans). On average, automatically created plans are superior to manually created treatment plans. For particular plans, experienced physicists were able to perform better than scripts or AP; thus, the benefit is greatest when time is short or staff inexperienced. (orig.) [German] Intensitaetsmodulierte Strahlentherapie (IMRT) hat sich als Standard durchgesetzt. Mit IMRT oder volumenmodulierter Arc-Therapie (VMAT) lassen sich

  8. Multi-institutional comparison of simulated treatment delivery errors in ssIMRT, manually planned VMAT and autoplan-VMAT plans for nasopharyngeal radiotherapy

    DEFF Research Database (Denmark)

    Pogson, Elise M; Aruguman, Sankar; Hansen, Christian R

    2017-01-01

    PURPOSE: To quantify the impact of simulated errors for nasopharynx radiotherapy across multiple institutions and planning techniques (auto-plan generated Volumetric Modulated Arc Therapy (ap-VMAT), manually planned VMAT (mp-VMAT) and manually planned step and shoot Intensity Modulated Radiation...... Therapy (mp-ssIMRT)). METHODS: Ten patients were retrospectively planned with VMAT according to three institution's protocols. Within one institution two further treatment plans were generated using differing treatment planning techniques. This resulted in mp-ssIMRT, mp-VMAT, and ap-VMAT plans. Introduced...

  9. A Monte Carlo code for ion beam therapy

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    Initially developed for applications in detector and accelerator physics, the modern Fluka Monte Carlo code is now used in many different areas of nuclear science. Over the last 25 years, the code has evolved to include new features, such as ion beam simulations. Given the growing use of these beams in cancer treatment, Fluka simulations are being used to design treatment plans in several hadron-therapy centres in Europe.   Fluka calculates the dose distribution for a patient treated at CNAO with proton beams. The colour-bar displays the normalized dose values. Fluka is a Monte Carlo code that very accurately simulates electromagnetic and nuclear interactions in matter. In the 1990s, in collaboration with NASA, the code was developed to predict potential radiation hazards received by space crews during possible future trips to Mars. Over the years, it has become the standard tool to investigate beam-machine interactions, radiation damage and radioprotection issues in the CERN accelerator com...

  10. Dosimetric effect of statistics noise of the TC image in the simulation Monte Carlo of radiotherapy treatments; Efecto dosimetrico del ruido estadistico de la imagen TC en la simulacion Monte Carlo de tratamientos de radioterapia

    Energy Technology Data Exchange (ETDEWEB)