WorldWideScience

Sample records for auto-contoured target volume

  1. Comparison of primary target volumes delineated on four-dimensional CT and 18 F-FDG PET/CT of non-small-cell lung cancer

    International Nuclear Information System (INIS)

    To determine the optimal threshold of 18 F-fluorodexyglucose (18 F-FDG) positron emission tomography CT (PET/CT) images that generates the best volumetric match to internal gross target volume (IGTV) based on four-dimensional CT (4DCT) images. Twenty patients with non-small cell lung cancer (NSCLC) underwent enhanced three-dimensional CT (3DCT) scan followed by enhanced 4DCT scan of the thorax under normal free breathing with the administration of intravenous contrast agents. A total of 100 ml of ioversol was injected intravenously, 2 ml/s for 3DCT and 1 ml/s for 4DCT. Then 18 F-FDG PET/CT scan was performed based on the same positioning parameters (the same immobilization devices and identical position verified by laser localizer as well as skin marks). Gross target volumes (GTVs) of the primary tumor were contoured on the ten phases images of 4DCT to generate IGTV10. GTVPET were determined with eight different threshold using an auto-contouring function. The differences in the position, volume, concordance index (CI) and degree of inclusion (DI) of the targets between GTVPET and IGTV10 were compared. The images from seventeen patients were suitable for further analysis. Significant differences between the centric coordinate positions of GTVPET (excluding GTVPET15%) and IGTV10 were observed only in z axes (P < 0.05). GTVPET15%, GTVPET25% and GTVPET2.0 were not statistically different from IGTV10 (P < 0.05). GTVPET15% approximated closely to IGTV10 with median percentage volume changes of 4.86%. The best CI was between IGTV10 and GTVPET15% (0.57). The best DI of IGTV10 in GTVPET was IGTV10 in GTVPET15% (0.80). None of the PET-based contours had both close spatial and volumetric approximation to the 4DCT IGTV10. At present 3D-PET/CT should not be used for IGTV generation

  2. Irradiation of target volumes with concave outlines

    Energy Technology Data Exchange (ETDEWEB)

    De Neve, W.; Fortan, L.; Derycke, S.; Van Duyse, B.; DE Wagter, C. [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde

    1995-12-01

    A heuristic planning procedure allowing to obtain a 3-dimensional conformal dose distribution for target volumes with concavities has been investigated. The procedure divides the planning problem into a number of sub-problems each solvable by known methods. By patching together the solutions to the sub-problems, a solution with a predictable dosimetric outcome can be obtained. The procedure can be applied to most 3-dimensional systems. The procedure is described and its applications to the irradiation of neoplasms are discussed. (A.S.).

  3. Target volume definition in radiation oncology

    International Nuclear Information System (INIS)

    The main objective of this book is to provide radiation oncologists with a clear, up-to-date guide to tumor delineation and contouring of organs at risk. With this in mind, a detailed overview of recent advances in imaging for radiation treatment planning is presented. Novel concepts for target volume delineation are explained, taking into account the innovations in imaging technology. Special attention is paid to the role of the newer imaging modalities, such as positron emission tomography and diffusion and perfusion magnetic resonance imaging. All of the most important tumor entities treated with radiation therapy are covered in the book. Each chapter is devoted to a particular tumor type and has been written by a recognized expert in that topic.

  4. Target volume definition in radiation oncology

    Energy Technology Data Exchange (ETDEWEB)

    Grosu, Anca-Ligia [Univ. Medical Center Freiburg (Germany). Dept. of Radiation Oncology; Nieder, Carsten (ed.) [Nordland Hospital, Bodo (Norway). Dept. of Oncology

    2015-05-01

    The main objective of this book is to provide radiation oncologists with a clear, up-to-date guide to tumor delineation and contouring of organs at risk. With this in mind, a detailed overview of recent advances in imaging for radiation treatment planning is presented. Novel concepts for target volume delineation are explained, taking into account the innovations in imaging technology. Special attention is paid to the role of the newer imaging modalities, such as positron emission tomography and diffusion and perfusion magnetic resonance imaging. All of the most important tumor entities treated with radiation therapy are covered in the book. Each chapter is devoted to a particular tumor type and has been written by a recognized expert in that topic.

  5. [Clinical to planning target volume margins in prostate cancer radiotherapy].

    Science.gov (United States)

    Ramiandrisoa, F; Duvergé, L; Castelli, J; Nguyen, T D; Servagi-Vernat, S; de Crevoisier, R

    2016-10-01

    The knowledge of inter- and intrafraction motion and deformations of the intrapelvic target volumes (prostate, seminal vesicles, prostatectomy bed and lymph nodes) as well as the main organs at risk (bladder and rectum) allow to define rational clinical to planning target volume margins, depending on the different radiotherapy techniques and their uncertainties. In case of image-guided radiotherapy, prostate margins and seminal vesicles margins can be between 5 and 10mm. The margins around the prostatectomy bed vary from 10 to 15mm and those around the lymph node clinical target volume between 7 and 10mm. Stereotactic body radiotherapy allows lower margins, which are 3 to 5mm around the prostate. Image-guided and stereotactic body radiotherapy with adequate margins allow finally moderate or extreme hypofractionation. PMID:27614515

  6. Target volume definition and target conformal irradiation technique for breast cancer patients.

    Science.gov (United States)

    Kiricuta, I C; Götz, U; Schwab, F; Fehn, M; Neumann, H H

    2000-01-01

    The aim of this study was to present the target volume and irradiation technique in the most complex situation where the breast or chest wall and the locoregional lymphatics (mammaria interna lymph nodes, axillary and supraclavicular lymph nodes) have to be irradiated. The study comprised 125 breast cancer patients treated with curative intent after primary surgery in the last two years at our institute. In 62 cases the target volume included the breast or chest wall and the locoregional lymphatics, which were treated using our irradiation technique. The target conformal irradiation technique is a multiple non-opposed beams one isocenter technique developed to protect the heart and lungs. This technique, consisting of several rotation beams modulated with wedge filters and individual lung absorbers as well as additional fixed beams, was used in our study to apply a homogeneous dose of 46 to 56 Gy to the target volume; the irradiation technique was optimized by means of dose-volume histograms. After pre-localization, the patients underwent computerized tomographic scanning, with sections at 1.0 cm intervals. Contouring of target volume and organs at risk was carried out with a MULTIDATA workstation for regions of interest (mammaria interna and/or axillary and/or supraclavicular lymphatics and the breast or chest wall) as well as the organs at risk, such as heart and lung parenchyma. Planning target volume coverage was examined by three-dimensional isodose visualization for all CT axial sections for each patient. To determine the incidence of acute or late side effects on the lung parenchyma, conventional chest x-rays and CT studies were carried out at 1 month, 3 months and 6 months after completion of radiotherapy. Dose-volume histogram analysis revealed that this irradiation technique permits the application of a homogeneous dose to the target volume, conforming to the ICRU norms. The maximum dose applied to the ipsilateral lung parenchyma was less than 50-70% of

  7. Diffusion tensor imaging for target volume definition in glioblastoma multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Berberat, Jatta; Remonda, Luca [Cantonal Hospital, Department of Neuro-radiology, Aarau (Switzerland); McNamara, Jane; Rogers, Susanne [Cantonal Hospital, Department of Radiation Oncology, Aarau (Switzerland); Bodis, Stephan [Cantonal Hospital, Department of Radiation Oncology, Aarau (Switzerland); University Hospital, Department of Radiation Oncology, Zurich (Switzerland)

    2014-10-15

    Diffusion tensor imaging (DTI) is an MR-based technique that may better detect the peritumoural region than MRI. Our aim was to explore the feasibility of using DTI for target volume delineation in glioblastoma patients. MR tensor tracts and maps of the isotropic (p) and anisotropic (q) components of water diffusion were coregistered with CT in 13 glioblastoma patients. An in-house image processing program was used to analyse water diffusion in each voxel of interest in the region of the tumour. Tumour infiltration was mapped according to validated criteria and contralateral normal brain was used as an internal control. A clinical target volume (CTV) was generated based on the T{sub 1}-weighted image obtained using contrast agent (T{sub 1Gd}), tractography and the infiltration map. This was compared to a conventional T{sub 2}-weighted CTV (T{sub 2}-w CTV). Definition of a diffusion-based CTV that included the adjacent white matter tracts proved highly feasible. A statistically significant difference was detected between the DTI-CTV and T{sub 2}-w CTV volumes (p < 0.005, t = 3.480). As the DTI-CTVs were smaller than the T{sub 2}-w CTVs (tumour plus peritumoural oedema), the pq maps were not simply detecting oedema. Compared to the clinical planning target volume (PTV), the DTI-PTV showed a trend towards volume reduction. These diffusion-based volumes were smaller than conventional volumes, yet still included sites of tumour recurrence. Extending the CTV along the abnormal tensor tracts in order to preserve coverage of the likely routes of dissemination, whilst sparing uninvolved brain, is a rational approach to individualising radiotherapy planning for glioblastoma patients. (orig.) [German] Die Diffusions-Tensor-Bildgebung (DTI) ist eine MR-Technik, die dank der Erfassung des peritumoralen Bereichs eine Verbesserung bezueglich MRI bringt. Unser Ziel war die Pruefung der Machbarkeit der Verwendung der DTI fuer die Zielvolumenabgrenzung fuer Patienten mit

  8. [Gross tumor volume (GTV) and clinical target volume (CTV) in radiotherapy of benign skull base tumors].

    Science.gov (United States)

    Maire, J P; Liguoro, D; San Galli, F

    2001-10-01

    Skull base tumours represent about 35 to 40% of all intracranial tumours. There are now many reports in the literature confirming the fact that about 80 to 90% of such tumours are controlled with fractionated radiotherapy. Stereotactic and 3-dimensional treatment planning techniques increase local control and central nervous system tolerance. Definition of the gross tumor volume (GTV) is generally easy with currently available medical imaging systems and computers for 3-dimensional dosimetry. The definition of the clinical target volume (CTV) is more difficult to appreciate; it is defined from the CTV plus a margin, which depends on the histology and anterior therapeutic history of the tumour. It is important to take into account the visible tumour and its possible extension pathways (adjacent bone, holes at the base of skull) and/or an anatomic region (sella turcica + adjacent cavernous sinus). It is necessary to evaluate these volumes with CT Scan and MRI to appreciate tumor extension in a 3-dimentional approach, in order to reduce the risk of marginal recurrences. The aim of this paper is to discuss volume definition as a function of tumour site and tumour type to be irradiated. PMID:11715310

  9. [Gross tumor volume (GTV) and clinical target volume (CTV) in adult gliomas].

    Science.gov (United States)

    Kantor, G; Loiseau, H; Vital, A; Mazeron, J J

    2001-10-01

    Glioblastoma multiform and astrocytoma are the most frequent primary cancer of the central nervous system of adult. Definitions of gross tumor volume (GTV) and clinical target volume (CTV) are based on the confrontation of clinical presentation (age, performance status, neurologic symptoms...), histological type and imaging aspects. For glioblastoma multiform, the GTV can be defined by the area of contrast enhancement observed on the CT scan or MRI. Definition of the CTV can be more difficult and have to take into account the risk of presence of isolated malignant cells in the oedema surrounding the tumor or in the adjacent brain structures. The classical concept of GTV plus a safety margin of 2 cm around is discussed with a CTV containing at least all the oedematous area and eventually adjacent brain structures (nuclei, corpus callosum or other long associative fibers...). For low grade astrocytoma, the definition of GTV can be difficult if the tumoral infiltration is diffuse without nodular visible tumor. CTV corresponds to at least T2 MRI hypersignal area when visible. For postoperative tumor, technical considerations are important for the detection of residual tumor. A safety margin around the resected area is designed according to the risk of presence of isolated cells or involvement of adjacent brain structures. PMID:11715309

  10. Target volume delineation variation in radiotherapy for early stage rectal cancer in the Netherlands

    NARCIS (Netherlands)

    Nijkamp, Jasper; de Haas-Kock, Danielle F. M.; Beukema, Jannet C.; Neelis, Karen J.; Woutersen, Dankert; Ceha, Heleen; Rozema, Tom; Slot, Annerie; Vos-Westerman, Hanneke; Intven, Martijn; Spruit, Patty H.; van der Linden, Yvette; Geijsen, Debby; Verschueren, Karijn; van Herk, Marcel B.; Marijnen, Corrie A. M.

    2012-01-01

    Purpose: The aim of this study was to measure and improve the quality of target volume delineation by means of national consensus on target volume definition in early-stage rectal cancer. Methods and materials: The CTV's for eight patients were delineated by 11 radiation oncologists in 10 institutes

  11. Technology transfer from NASA to targeted industries, volume 2

    Science.gov (United States)

    Mccain, Wayne; Schroer, Bernard J.; Souder, William E.; Spann, Mary S.; Watters, Harry; Ziemke, M. Carl

    1993-01-01

    This volume contains the following materials to support Volume 1: (1) Survey of Metal Fabrication Industry in Alabama; (2) Survey of Electronics Manufacturing/Assembly Industry in Alabama; (3) Apparel Modular Manufacturing Simulators; (4) Synopsis of a Stereolithography Project; (5) Transferring Modular Manufacturing Technology to an Apparel Firm; (6) Letters of Support; (7) Fact Sheets; (8) Publications; and (9) One Stop Access to NASA Technology Brochure.

  12. Volume-Targeted Versus Pressure-Targeted Noninvasive Ventilation in Patients With Chest-Wall Deformity : A Pilot Study

    NARCIS (Netherlands)

    Struik, Fransien M.; Duiverman, Marieke L.; Meijer, Petra M.; Nieuwenhuis, Jellie A.; Kerstjens, Huib A. M.; Wijkstra, Peter J.

    2011-01-01

    BACKGROUND: Long-term noninvasive ventilation (NIV) is an effective treatment for patients with chronic respiratory failure due to chest-wall deformity, but it is unknown if the time required for the patient to adjust to long-term NIV depends on whether the NIV is volume-targeted or pressure-targete

  13. Delineation of Supraclavicular Target Volumes in Breast Cancer Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Lindsay C. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Diehn, Felix E. [Department of Radiology, Mayo Clinic, Rochester, Minnesota (United States); Boughey, Judy C. [Department of Surgery, Mayo Clinic, Rochester, Minnesota (United States); Childs, Stephanie K.; Park, Sean S.; Yan, Elizabeth S.; Petersen, Ivy A. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Mutter, Robert W., E-mail: mutter.robert@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2015-07-01

    Purpose: To map the location of gross supraclavicular metastases in patients with breast cancer, in order to determine areas at highest risk of harboring subclinical disease. Methods and Materials: Patients with axial imaging of gross supraclavicular disease were identified from an institutional breast cancer registry. Locations of the metastatic lymph nodes were transferred onto representative axial computed tomography images of the supraclavicular region and compared with the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning. Results: Sixty-two patients with 161 supraclavicular nodal metastases were eligible for study inclusion. At the time of diagnosis, 117 nodal metastases were present in 44 patients. Forty-four nodal metastases in 18 patients were detected at disease recurrence, 4 of whom had received prior radiation to the supraclavicular fossa. Of the 161 nodal metastases, 95 (59%) were within the RTOG consensus volume, 4 nodal metastases (2%) in 3 patients were marginally within the volume, and 62 nodal metastases (39%) in 30 patients were outside the volume. Supraclavicular disease outside the RTOG consensus volume was located in 3 regions: at the level of the cricoid and thyroid cartilage (superior to the RTOG volume), in the posterolateral supraclavicular fossa (posterolateral to the RTOG volume), and in the lateral low supraclavicular fossa (lateral to the RTOG volume). Only women with multiple supraclavicular metastases had nodal disease that extended superiorly to the level of the thyroid cartilage. Conclusions: For women with risk of harboring subclinical supraclavicular disease warranting the addition of supraclavicular radiation, coverage of the posterior triangle and the lateral low supraclavicular region should be considered. For women with known supraclavicular disease, extension of neck coverage superior to the cricoid cartilage may be warranted.

  14. [Definition of accurate planning target volume margins for esophageal cancer radiotherapy].

    Science.gov (United States)

    Lesueur, P; Servagi-Vernat, S

    2016-10-01

    More than 4000 cases of esophagus neoplasms are diagnosed every year in France. Radiotherapy, which can be delivered in preoperative or exclusive with a concomitant chemotherapy, plays a central role in treatment of esophagus cancer. Even if efficacy of radiotherapy no longer has to be proved, the prognosis of esophagus cancer remains unfortunately poor with a high recurrence rate. Toxicity of esophageal radiotherapy is correlated with the irradiation volume, and limits dose escalation and local control. Esophagus is a deep thoracic organ, which undergoes cardiac and respiratory motion, making the radiotherapy delivery more difficult and increasing the planning target volume margins. Definition of accurate planning target volume margins, taking into account the esophagus' intrafraction motion and set up margins is very important to be sure to cover the clinical target volume and restrains acute and late radiotoxicity. In this article, based on a review of the literature, we propose planning target volume margins adapted to esophageal radiotherapy.

  15. Target volume definition for three-dimensional conformal radiation therapy of lung cancer.

    Science.gov (United States)

    Armstrong, J G

    1998-06-01

    Three-dimensional conformal radiation therapy (3DCRT) is a mode of high precision radiotherapy which has the potential to improve the therapeutic ratio of radiation therapy for locally advanced non-small cell lung cancer. The preliminary clinical experience with 3DCRT has been promising and justifies further endeavour to refine its clinical application and ultimately test its role in randomized trials. There are several steps to be taken before 3DCRT evolves into an effective single modality for the treatment of lung cancer and before it is effectively integrated with chemotherapy. This article addresses core issues in the process of target volume definition for the application of 3DCRT technology to lung cancer. The International Commission on Radiation Units and Measurements Report no. 50 definitions of target volumes are used to identify the factors influencing target volumes in lung cancer. The rationale for applying 3DCRT to lung cancer is based on the frequency of failure to eradicate gross tumour with conventional approaches. It may therefore be appropriate to ignore subclinical or microscopic extensions when designing a clinical target volume, thereby restricting target volume size and allowing dose escalation. When the clinical target volume is expanded to a planning target volume, an optimized margin would result in homogeneous irradiation to the highest dose feasible within normal tissue constraints. To arrive at such optimized margins, multiple factors, including data acquisition, data transfer, patient movement, treatment reproducibility, and internal organ and target volume motion, must be considered. These factors may vary significantly depending on technology and techniques, and published quantitative analyses are no substitute for meticulous attention to detail and audit of performance. PMID:9849380

  16. Rectal cancer: The radiation basis of radiotherapy, target volume; Cancers du rectum: volumes cible de la radiotherapie, bases rationnelles

    Energy Technology Data Exchange (ETDEWEB)

    Bosset, J.F.; Servagi-Vernat, S. [Service oncologie-radiotherapie, CHU Jean-Minjoz, 3, boulevard Fleming, 25030 Besancon (France); Crehange, G. [Service oncologie-radiotherapie, centre Georges-Francois-Leclerc, 1, rue du Pr-Marion, 21079 Dijon cedex (France); Azria, D. [Service oncologie-radiotherapie, centre Val-d' Aurelle, rue Croix-Verte, 34298 Montpellier cedex 5 (France); Gerard, J.P. [Service oncologie-radiotherapie, centre Antoine-Lacassagne, 33, avenue Valombrose, 06189 Nice (France); Hennequin, C. [Service oncologie-radiotherapie, hopital Saint-Louis, 1, avenue Claude-Vellefaux, 75475 Paris (France)

    2011-10-15

    Since the implementation of preoperative chemo-radiotherapy and meso-rectal excision, the 5-year rates of locoregional failures in T3-T4 N0-N1M0 rectal cancer fell from 25-30% thirty years ago to 5-8% nowadays. A critical analysis of the locoregional failures sites and mechanisms, as well as the identification of nodal extension, helps the radiation oncologist to optimize the radiotherapy target definition. The upper limit of the clinical target volume is usually set at the top of the third sacral vertebra. The lateral pelvic nodes should be included when the tumor is located in the distal part of the rectum. The anal sphincter and the levator muscles should be spared when a conservative surgery is planned. In case of abdomino-perineal excision, the ischio-rectal fossa and the sphincters should be included in the clinical target volume. A confrontation with radiologist and surgeon is mandatory to improve the definition of the target volumes to be treated. (authors)

  17. Repeated CT scan in improving the reproducibility of grass tumor volume for moving target

    International Nuclear Information System (INIS)

    Objective: To find a method to improve the range accuracy of moving target such as peripheral lung tumors, since a single CT snapshot may not be accurate during the treatment process.Methods: A simple harmonic motion phantom, embedded with a cube and a circular ball, was used to simulate the tumor motion. Individualized moving targets were scanned 24 times with different amplitudes and frequencies. Then the images were fused from every 1, 2 or 3 sets of CT scans. The GTV volume variation of circular target and the length variation of the cube target along the z axis were contoured and analyzed. Results: As motion amplitude increased, the maximum of both circular target volume and cube target length was increased, while the minimum of the factors was decreased. Motion frequency affected the target volume less than amplitude. For a cube target with the length of 3.3 cm at stationary phase, when motion frequencies was 20 and motion amplitude was 2 cm, the maximal length was 2. 4 times of the minimal length (5. 1 cm vs. 2. 1 cm). When it came to the cube target groups fused from every 1,2 and 3 sets of CT scans, the average length and standard deviation were (3.77 ± 1.20)cm, (4.18 ±0. 91)cm and (4.52 ±0. 59)cm, respectively. With the increase of fused scan number, targets became bigger, the standard deviation decreased, and the change of center positions was decreased. Conclusions: The motion amplitude, frequency and the number of CT scans are the main factors affecting target definition, though, the optimized scanning phase is not certained. When 4DCT and respiration gating technique are not available,the efficient and practical method to solve this problem is to scan the target three or more times and fuse them in planning system, which will generate a larger, more reproducible GTV volume for moving targets. (authors)

  18. Organs at risk and target volumes: Definition for conformal radiation therapy in breast cancer

    International Nuclear Information System (INIS)

    Adjuvant radiotherapy is a standard component of breast cancer treatment. The addition of radiotherapy after breast conserving surgery has been shown to reduce local recurrence rate and improve long-term survival. Accurate delineation of target volumes and organs at risk is crucial to the quality of treatment planning and delivered accomplished with innovate technologies in radiation therapy. This allows the radiation beam to be shaped specifically to each individual patient's anatomy. Target volumes include the mammary gland and surgical bed in case of breast conserving surgery, the chest wall in case of mastectomy, and if indicated, regional lymph nodes (axillary, supra- and infra-clavicular and internal mammary). Organs at risk include lungs, thyroid, brachial plexus, heart, spinal cord and oesophagus. The aim of this article is to encourage the use of conformal treatment and delineation of target volumes and organs at risk and to describe specifically the definition of these volumes. (authors)

  19. Optimal target search on a fast-folding polymer chain with volume exchange

    DEFF Research Database (Denmark)

    Lomholt, Michael Andersen; Ambjörnsson, T.; Metzler, R.

    2005-01-01

    We study the search process of a target on a rapidly folding polymer ("DNA") by an ensemble of particles ("proteins"), whose search combines 1D diffusion along the chain, Lévy type diffusion mediated by chain looping, and volume exchange. A rich behavior of the search process is obtained with res......We study the search process of a target on a rapidly folding polymer ("DNA") by an ensemble of particles ("proteins"), whose search combines 1D diffusion along the chain, Lévy type diffusion mediated by chain looping, and volume exchange. A rich behavior of the search process is obtained...

  20. Analysis of target volumes for gliomas; Volumes-cibles anatomocliniques (GTV et CTV) des tumeurs gliales

    Energy Technology Data Exchange (ETDEWEB)

    Kantor, G. [Centre Regional de Lutte Contre le Cancer, Service de Radiotherapie, Institut Bergonie, 33 - Bordeaux (France); Bordeaux-2 Univ., 33 (France); Loiseau, H. [Hopital Pellegrin-Tripode, Service de Neurochirurgie, 33 - Bordeaux (France); Bordeaux-2 Univ., 33 (France)

    2005-06-15

    Gliomas are the most frequent tumors of the central nervous system of the adult. These intra-parenchymal tumors are infiltrative and the most important criterion for definition of GTV and CTV is the extent of infiltration. Delineation of GTV and CTV for untreated and resected glioma remains a controversial and difficult issue because of the discrepancy between real tumor invasion and that estimated by CT or MRI. Is particularly helpful a joint analysis of the four different methods as histopathological correlations with CT and MRI, use of new modality imaging, pattern of relapses after treatment and interobserver studies. The presence of isolated tumor cells in intact brain, oedema or adjacent structures requires the definition of two different options for CTV: i) a geometrical option with GTV defined as the tumor mass revealed by the contrast-enhanced zone on CT or MRI and a CTV with an expanded margin of 2 or 3 cm; ii) an anatomic option including the entire zone of oedema or isolated tumor cell infiltration extending at least as far as the limits of the hyperintense zone on T2-weighted MRI. Inclusion of adjacent structures (such as white matter, corpus callosum, subarachnoid spaces) in the CTV mainly depends on the site of the tumor and size of the volume is generally enlarged. (authors)

  1. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer

    NARCIS (Netherlands)

    Offersen, B.V.; Boersma, L.J.; Kirkove, C.; Hol, S.; Aznar, M.C.; Sola, A. Biete; Kirova, Y.M.; Pignol, J.P.; Remouchamps, V.; Verhoeven, K.; Weltens, C.; Arenas, M.; Gabrys, D.; Kopek, N.; Krause, M.; Lundstedt, D.; Marinko, T.; Montero, A.; Yarnold, J.; Poortmans, P.M.P.

    2015-01-01

    BACKGROUND AND PURPOSE: Delineation of clinical target volumes (CTVs) is a weak link in radiation therapy (RT), and large inter-observer variation is seen in breast cancer patients. Several guidelines have been proposed, but most result in larger CTVs than based on conventional simulator-based RT. T

  2. Selection and delineation of target volumes in head and neck tumors: beyond ICRU definition

    International Nuclear Information System (INIS)

    Improvement in irradiation techniques, which allows dose distributions sculpting around volumes of very complex shapes, has revealed the limitations in selection and delineation of target volumes. The use of functional imaging (PET, fMRI) in addition to anatomic imaging, will probably bring an extra level of complexity to this issue. In particular, the use of specific markers to visualize biological pathways known to influence response to ionizing radiation (e.g. hypoxia, proliferation) could lead to the delineation of sub-target volumes for delivering an extra boost dose. Such concept of Image-Guided Radiation Therapy still need to be tested in experimental models and in well defined clinical situations before its use in a routine clinical set-up. (author)

  3. Target Centroid Position Estimation of Phase-Path Volume Kalman Filtering

    Directory of Open Access Journals (Sweden)

    Fengjun Hu

    2016-01-01

    Full Text Available For the problem of easily losing track target when obstacles appear in intelligent robot target tracking, this paper proposes a target tracking algorithm integrating reduced dimension optimal Kalman filtering algorithm based on phase-path volume integral with Camshift algorithm. After analyzing the defects of Camshift algorithm, compare the performance with the SIFT algorithm and Mean Shift algorithm, and Kalman filtering algorithm is used for fusion optimization aiming at the defects. Then aiming at the increasing amount of calculation in integrated algorithm, reduce dimension with the phase-path volume integral instead of the Gaussian integral in Kalman algorithm and reduce the number of sampling points in the filtering process without influencing the operational precision of the original algorithm. Finally set the target centroid position from the Camshift algorithm iteration as the observation value of the improved Kalman filtering algorithm to fix predictive value; thus to make optimal estimation of target centroid position and keep the target tracking so that the robot can understand the environmental scene and react in time correctly according to the changes. The experiments show that the improved algorithm proposed in this paper shows good performance in target tracking with obstructions and reduces the computational complexity of the algorithm through the dimension reduction.

  4. The use of positron emission tomography/computed tomography imaging in radiation therapy: a phantom study for setting internal target volume of biological target volume

    International Nuclear Information System (INIS)

    Fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is an important method for detecting tumours, planning radiotherapy treatment, and evaluating treatment responses. However, using the standardized uptake value (SUV) threshold with PET imaging may be suitable not to determine gross tumour volume but to determine biological target volume (BTV). The aim of this study was to extract internal target volume of BTV from PET images. Three spherical densities of 18F-FDG were employed in a phantom with an air or water background with repetitive motion amplitudes of 0–30 mm. The PET data were reconstructed with attenuation correction (AC) based on CT images obtained by slow CT scanning (SCS) or helical CT scanning (HCS). The errors in measured SUVmax and volumes calculated using SUV threshold values based on SUVmax (THmax) in experiments performed with varying extents of respiratory motion and AC were analysed. A partial volume effect (PVE) was not observed in spheres with diameters of ≥ 28 mm. When calculating SUVmax and THmax, using SCS for AC yielded smaller variance than using HCS (p < 0.05). For spheres of 37- and 28-mm diameters in the phantom with either an air or water background, significant differences were observed when mean THmax of 30-, 20-, or 10-mm amplitude were compared with the stationary conditions (p < 0.05). The average THmax values for 37-mm and 28-mm spheres with an air background were 0.362 and 0.352 in non-motion, respectively, and the mean THmax values for 37-mm and 28-mm spheres with a water background were 0.404 and 0.387 in non-motion and 0.244 and 0.263 in motion, respectively. When the phantom background was air, regardless of sphere concentration or size, THmax was dependent only on motion amplitude. We found that there was no PVE for spheres with ≥ 28-mm diameters, and differences between SUVmax and THmax were reduced by using SCS for AC. In the head-and-neck and the abdomen, the standard values of

  5. The effect of image-guided radiation therapy on the margin between the clinical target volume and planning target volume in lung cancer

    International Nuclear Information System (INIS)

    Introduction: This study aimed to evaluate the effect of image-guided radiation therapy (IGRT) on the margin between the clinical target volume (CTV) and planning target volume (PTV) in lung cancer. Methods: The CTV and PTV margin were determined in three dimensions by four radiation oncologists using a standard method in 10 lung cancer patients, and compared to consensus values. Transfer error was measured using a rigid phantom containing gold markers. Systematic error and random error set up errors were calculated in three dimensions from pre-treatment and post-treatment cone beam CT scans. Finally, the margin between the CTV and PTV was corrected for set up error and calculated. Results: The margins between the CTV and PTV with IGRT (and without IGRT) were 0.88 cm (0.96 cm), 0.99 cm (1.08 cm) and 1.28 cm (1.82 cm) in the anterior and posterior (AP), left and right (LR) and superior and inferior (SI) directions, respectively. Images from two other patients verified the validity of the corrected margin. The target delineation errors of the radiation oncologists are considered to be the largest compared with the set up errors. The application of IGRT reduced the set up errors and the margins between CTV and PTV. Conclusions: The delineation errors of radiation oncologists are the most important factor to consider for the margin between CTV and PTV for lung cancer. IGRT can reduce the margins by reducing the set up errors, especially in the SI direction. Further research is required to assess whether the reduction in the margin is solely based on set up errors

  6. Optimized planning target volume margin in helical tomotherapy for prostate cancer: is there a preferred method?

    CERN Document Server

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

    2015-01-01

    To compare the dosimetrical differences between plans generated by helical tomotherapy using 2D or 3D margining technique in in prostate cancer. Ten prostate cancer patients were included in this study. For 2D plans, planning target volume (PTV) was created by adding 5 mm (lateral/anterior-posterior) to clinical target volume (CTV). For 3D plans, 5 mm margin was added not only in lateral/anterior-posterior, but also in superior-inferior to CTV. Various dosimetrical indices, including the prescription isodose to target volume (PITV) ratio, conformity index (CI), homogeneity index (HI), target coverage index (TCI), modified dose homogeneity index (MHI), conformation number (CN), critical organ scoring index (COSI), and quality factor (QF) were determined to compare the different treatment plans. Differences between 2D and 3D PTV indices were not significant except for CI (p = 0.023). 3D margin plans (11195 MUs) resulted in higher (13.0%) monitor units than 2D margin plans (9728 MUs). There were no significant d...

  7. Target volume and position variations during intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Tan W

    2013-11-01

    Full Text Available Wenyong Tan,* Yanping Li,* Guang Han, Jiaozhen Xu, Xiaohong Wang, Ying Li, Desheng HuDepartment of Radiation Oncology, Hubei Cancer Hospital, Wuhan, People's Republic of China*These authors contributed equally to this workPurpose: Considerable anatomical changes occur during intensity-modulated radiotherapy (IMRT for nasopharyngeal carcinoma (NPC. This study aimed to quantify volumetric and positional variations of the target volume during IMRT.Materials and methods: Twenty patients with locally advanced NPC who received concurrent (13 patients or sequential (seven patients chemoradiotherapy were prospectively recruited and underwent planning computed tomography (CT and six repeat CTs (every five fractions. Each repeat CT was rigidly registered to the planning CT. Gross tumor volume (GTV and elective clinical target volume (CTV were manually delineated on each axial CT image. CTVs of the primary tumor and lymph nodes were expanded with 5 mm margins to corresponding GTVs, with necessary modifications. Volume loss, system and random errors, and the mean and three-dimensional vector displacements were calculated and compared statistically.Results: Volumes of the primary tumor and small (>1 cm, ≤3 cm and large (>3 cm positive neck lymph nodes decreased at a rate of 2.6%, 3.7%, and 3.9% per treatment day, respectively. CTVs of the primary tumor, lymph nodes, and elective region decreased 1.5%, 2.3%, and 0.3% per treatment day, respectively. Average displacements of the GTVs and CTVs were <1.3 mm in all directions. GTVs and CTVs of the large and small lymph nodes shifted medially by 0.8–1.3 and 0.6–1.2 mm, respectively, on average. Average three-dimensional displacements of the GTVs and CTVs were 3.4–4.3 mm and 2.5–3.7 mm, respectively. Volume loss and displacements in most directions were significantly larger in patients receiving concurrent chemoradiotherapy than in those receiving sequential therapy. Volume loss and displacements of the

  8. Target volume delineation in external beam partial breast irradiation: less inter-observer variation with preoperative- compared to postoperative delineation

    NARCIS (Netherlands)

    Leij, F. van der; Elkhuizen, P.H.M.; Janssen, T.M.; Poortmans, P.M.P.; Sangen, M. van der; Scholten, A.N.; Vliet-Vroegindeweij, C. van; Boersma, L.J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of

  9. SU-E-T-578: On Definition of Minimum and Maximum Dose for Target Volume

    International Nuclear Information System (INIS)

    Purpose: This study aims to investigate the impact of different minimum and maximum dose definitions in radiotherapy treatment plan quality evaluation criteria by using tumor control probability (TCP) models. Methods: Dosimetric criteria used in RTOG 1308 protocol are used in the investigation. RTOG 1308 is a phase III randomized trial comparing overall survival after photon versus proton chemoradiotherapy for inoperable stage II-IIIB NSCLC. The prescription dose for planning target volume (PTV) is 70Gy. Maximum dose (Dmax) should not exceed 84Gy and minimum dose (Dmin) should not go below 59.5Gy in order for the plan to be “per protocol” (satisfactory).A mathematical model that simulates the characteristics of PTV dose volume histogram (DVH) curve with normalized volume is built. The Dmax and Dmin are noted as percentage volumes Dη% and D(100-δ)%, with η and d ranging from 0 to 3.5. The model includes three straight line sections and goes through four points: D95%= 70Gy, Dη%= 84Gy, D(100-δ)%= 59.5 Gy, and D100%= 0Gy. For each set of η and δ, the TCP value is calculated using the inhomogeneously irradiated tumor logistic model with D50= 74.5Gy and γ50=3.52. Results: TCP varies within 0.9% with η; and δ values between 0 and 1. With η and η varies between 0 and 2, TCP change was up to 2.4%. With η and δ variations from 0 to 3.5, maximum of 8.3% TCP difference is seen. Conclusion: When defined maximum and minimum volume varied more than 2%, significant TCP variations were seen. It is recommended less than 2% volume used in definition of Dmax or Dmin for target dosimetric evaluation criteria. This project was supported by NIH grants U10CA180868, U10CA180822, U24CA180803, U24CA12014 and PA CURE Grant

  10. Gold markers for tumor localization and target volume delineation in radiotherapy for rectal cancer

    International Nuclear Information System (INIS)

    In locally advanced rectal cancer, neoadjuvant radiochemotherapy is indicated. To improve target volume definition for radiotherapy planning, the potential of implanted gold markers in the tumor region was evaluated. In nine consecutive patients, two to three gold markers were implanted in the tumor region during rigid rectoscopy. Computed tomography scans were performed during treatment planning. All electronic portal imaging devices (EPIDs) recorded during treatment series were analyzed. All patients underwent complete tumor resection with meticulous histopathologic examination. The gold markers could easily be implanted into the mesorectal tissue at the caudal tumor border without any complications. They were helpful in identifying the inferior border of the planning target volume in order to spare normal tissue (in particular anal structures). No significant shift of the markers was found during the course of therapy. Marker matching of the EPIDs did not improve patient positioning in comparison to bone structure matching. The former position of at least one marker could be identified in all patients during histopathologic examination. The use of gold marker enables a more precise definition of the target volume for radiotherapy in patients with rectal cancer. This could eventually allow a better protection of anal structures of patients with a tumor localization = 5 cm cranial of the anal sphincter. The implantation of the gold markers improved communication between the surgeon, the radiooncologist and the pathologist resulting in intensified exchange of relevant informations. (orig.)

  11. Apparent diffusion coefficients in GEC ESTRO target volumes for image guided adaptive brachytherapy of locally advanced cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Haack, Soeren (Dept. of Clinical Engineering, Aarhus Univ. Hospital (Denmark)), E-mail: Soeren.haack@stab.rm.dk; Morre Pedersen, Erik (Dept. of Radiology, Aarhus Sygehus, Aarhus Univ. Hospital (Denmark)); Jespersen, Sune N. (Center of Functionally Integrative Neuroscience, Aarhus Univ. Hospital (Denmark)); Kallehauge, Jesper F. (Dept. of Medical Physics, Aarhus Univ. Hospital (Denmark)); Lindegaard, Jacob Christian; Tanderup, Kari (Dept. of Oncology Aarhus Univ. Hospital (Denmark))

    2010-10-15

    Background and purpose. T2 weighted MRI is recommended for image guided adaptive brachytherapy (IGABT) in cervical cancer. Diffusion weighted imaging (DWI) and the derived apparent diffusion coefficient (ADC) may add additional biological information on tumour cell density. The purpose of this study was to evaluate the distribution of the ADC within target volumes as recommended by GEC-ESTRO: Gross Tumour Volume at BT (GTVBT), High-Risk Clinical Tumour Volume (HR-CTV) and Intermediate-Risk Clinical Target Volume (IR-CTV) and to evaluate the change of diffusion between fractions of IGABT. Material and methods. Fifteen patients with locally advanced cervical cancer were examined by MRI before their first (BT1) and second (BT2) fraction of IGABT, resulting in a total of 30 MR examinations including both T2 weighted and DWI sequences. The Apparent Diffusion Coefficient (ADC) was calculated by use of three levels of b-values (0, 600, 1000 s/mm2). ADC maps were constructed and fused with the GEC ESTRO target contours. The mean ADC value within each target volume was calculated. Furthermore, volumes of low diffusion (ADClow) were defined based on an ADC threshold of 1.2 x 10-3 mm2/s, and overlap with target volumes was evaluated. Change of ADC level in target volumes and change of ADClow volume from BT1 to BT2 was also evaluated. Results. The mean ADC was significantly lower in GTVBT than in HR-CTV (p<0.001) which again was significantly lower than in IR-CTV (p<0.001). There was no significant change of the ADClow volume or ADC level within each target structure between BT1 and BT2 (p=0.242). All three GEC-ESTRO volumes contained volumes with low diffusion. The GTVBT contained 37.2% volume of low diffusion, HR-CTV 20.3% and IR-CTV 10.8%. Conclusion. With DWI we were able to find a significant difference in ADC-values for the three different GEC ESTRO targets. This supports the assumption that the target volumes used for dose prescription in IGABT contain tissues with

  12. A prospective study of nomogram-based adaptation of prostate radiotherapy target volumes

    International Nuclear Information System (INIS)

    A prospective clinical trial was conducted to evaluate the feasibility of a novel approach to the treatment of patients with high risk prostate cancer (HRPC) through the use of a nomogram to tailor radiotherapy target volumes. Twenty seven subjects with HRPC were treated with a mildly hypofractionated radiotherapy regimen using image-guided IMRT technique between Jun/2013-Jan/2015. A set of validated prognostic factors were inputted into the Memorial-Sloan-Kettering Cancer Center (MSKCC) prostate cancer nomogram to estimate risk of loco-regional spread (LRS). The nomogram risk estimates for extra-capsular extension (ECE), seminal vesicles involvement (SVI), and pelvic lymph nodes involvement (LNI) were used to adapt radiotherapy treatment volumes based on a risk threshold of ≥15 % in all cases. A planning guide was used to delineate target volumes and organs at risk (OAR). Up to three dose levels were administered over 28 fractions; 70Gy for gross disease in the prostate +/− seminal vesicles (2.5Gy/fraction), 61.6Gy for subclinical peri-prostatic disease (2.2Gy/fraction) and 50.4Gy to pelvic nodes (1.8Gy/fraction). Data regarding protocol adherence, nomogram use, radiotherapy dose distribution, and acute toxicity were collected. Nomogram use 100 % of patients were treated for ECE, 88.9 % for SVI, and 70.4 % for LNI. The three areas at risk of LRS were appropriately treated according to the study protocol in 98.8 % cases. The MSKCC nomogram estimates for LRS differed significantly between the time of recruitment and analysis. Contouring protocol compliance Compliance with the trial contouring protocol for up to seven target volumes was 93.0 % (159/171). Compliance with protocol for small bowel contouring was poor (59.3 %). Dose constraints compliance Compliance with dose constraints for target volumes was 97.4 % (191/196). Compliance with dose constraints for OAR was 88.2 % (285/323). Acute toxicity There were no grade 3 acute toxicities observed. 20/27 (74

  13. Integration of three-dimensional magnetic resonance spectrometry to the irradiation treatment plan for glioblastomas: definition of new target volumes

    International Nuclear Information System (INIS)

    Based on a clinic trial, the authors report the definition of a new reliable and reproducible method to delimit and integrate targets to the treatment plan which are specific to magnetic resonance spectrometry imagery for the radiotherapy of glioblastomas, in order to perform a treatment by intensity-modulated conformational radiotherapy (IMRT). A weighted conventional MRI has been performed before radiotherapy. The importation of anatomic-metabolic images into the dose planning system comprises two steps: normalization on the whole volume of magnetic resonance spectrometry imagery, and segmentation of target volumes specific to spectrometry anomalies. This integration of target volumes is thus facilitated. Short communication

  14. Retroperitoneal Sarcoma Target Volume and Organ at Risk Contour Delineation Agreement Among NRG Sarcoma Radiation Oncologists

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, Elizabeth H., E-mail: ebaldini@partners.org [Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Abrams, Ross A. [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States); Bosch, Walter [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Roberge, David [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, Quebec (Canada); Haas, Rick L.M. [Department of Radiotherapy, Netherlands Cancer Institute, Amsterdam (Netherlands); Catton, Charles N. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Indelicato, Daniel J. [Department of Radiation Oncology, University of Florida Medical Center, Jacksonville, Florida (United States); Olsen, Jeffrey R. [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Deville, Curtiland [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Chen, Yen-Lin [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Finkelstein, Steven E. [Translational Research Consortium, 21st Century Oncology, Scottsdale, Arizona (United States); DeLaney, Thomas F. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Wang, Dian [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States)

    2015-08-01

    Purpose: The purpose of this study was to evaluate the variability in target volume and organ at risk (OAR) contour delineation for retroperitoneal sarcoma (RPS) among 12 sarcoma radiation oncologists. Methods and Materials: Radiation planning computed tomography (CT) scans for 2 cases of RPS were distributed among 12 sarcoma radiation oncologists with instructions for contouring gross tumor volume (GTV), clinical target volume (CTV), high-risk CTV (HR CTV: area judged to be at high risk of resulting in positive margins after resection), and OARs: bowel bag, small bowel, colon, stomach, and duodenum. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. Results: Ten radiation oncologists contoured both RPS cases, 1 contoured only RPS1, and 1 contoured only RPS2 such that each case was contoured by 11 radiation oncologists. The first case (RPS 1) was a patient with a de-differentiated (DD) liposarcoma (LPS) with a predominant well-differentiated (WD) component, and the second case (RPS 2) was a patient with DD LPS made up almost entirely of a DD component. Contouring agreement for GTV and CTV contours was high. However, the agreement for HR CTVs was only moderate. For OARs, agreement for stomach, bowel bag, small bowel, and colon was high, but agreement for duodenum (distorted by tumor in one of these cases) was fair to moderate. Conclusions: For preoperative treatment of RPS, sarcoma radiation oncologists contoured GTV, CTV, and most OARs with a high level of agreement. HR CTV contours were more variable. Further clarification of this volume with the help of sarcoma surgical oncologists is necessary to reach consensus. More attention to delineation of the duodenum is also needed.

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

    International Nuclear Information System (INIS)

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

  16. A method of calculating a lung clinical target volume DVH for IMRT with intrafractional motion.

    Science.gov (United States)

    Kung, J H; Zygmanski, P; Choi, N; Chen, G T Y

    2003-06-01

    The motion of lung tumors from respiration has been reported in the literature to be as large as 1-2 cm. This motion requires an additional margin between the Clinical Target Volume (CTV) and the Planning Target Volume (PTV). In Intensity Modulated Radiotherapy (IMRT), while such a margin is necessary, the margin may not be sufficient to avoid unintended high and low dose regions to the interior on moving CTV. Gated treatment has been proposed to improve normal tissues sparing as well as to ensure accurate dose coverage of the tumor volume. The following questions have not been addressed in the literature: (a) what is the dose error to a target volume without a gated IMRT treatment? (b) What is an acceptable gating window for such a treatment. In this study, we address these questions by proposing a novel technique for calculating the three-dimensional (3-D) dose error that would result if a lung IMRT plan were delivered without a gated linac beam. The method is also generalized for gated treatment with an arbitrary triggering window. IMRT plans for three patients with lung tumors were studied. The treatment plans were generated with HELIOS for delivery with 6 MV on a CL2100 Varian linear accelerator with a 26 pair MLC. A CTV to PTV margin of 1 cm was used. An IMRT planning system searches for an optimized fluence map phi(x,y) for each port, which is then converted into a dynamic MLC file (DMLC). The DMLC file contains information about MLC subfield shapes and the fractional Monitor Units (MUs) to be delivered for each subfield. With a lung tumor, a CTV that executes a quasiperiodic motion z(t) does not receive phi(x,y), but rather an Effective Incident Fluence EIF(x,y). We numerically evaluate the EIF(x,y) from a given DMLC file by a coordinate transformation to the Target's Eye View (TEV). In the TEV coordinate system, the CTV itself is stationary, and the MLC is seen to execute a motion -z(t) that is superimposed on the DMLC motion. The resulting EIF(x,y) is

  17. A method of calculating a lung clinical target volume DVH for IMRT with intrafractional motion

    International Nuclear Information System (INIS)

    The motion of lung tumors from respiration has been reported in the literature to be as large as 1-2 cm. This motion requires an additional margin between the Clinical Target Volume (CTV) and the Planning Target Volume (PTV). In Intensity Modulated Radiotherapy (IMRT), while such a margin is necessary, the margin may not be sufficient to avoid unintended high and low dose regions to the interior on moving CTV. Gated treatment has been proposed to improve normal tissues sparing as well as to ensure accurate dose coverage of the tumor volume. The following questions have not been addressed in the literature: (a) what is the dose error to a target volume without a gated IMRT treatment? (b) What is an acceptable gating window for such a treatment. In this study, we address these questions by proposing a novel technique for calculating the three-dimensional (3-D) dose error that would result if a lung IMRT plan were delivered without a gated linac beam. The method is also generalized for gated treatment with an arbitrary triggering window. IMRT plans for three patients with lung tumors were studied. The treatment plans were generated with HELIOS for delivery with 6 MV on a CL2100 Varian linear accelerator with a 26 pair MLC. A CTV to PTV margin of 1 cm was used. An IMRT planning system searches for an optimized fluence map Φ(x,y) for each port, which is then converted into a dynamic MLC file (DMLC). The DMLC file contains information about MLC subfield shapes and the fractional Monitor Units (MUs) to be delivered for each subfield. With a lung tumor, a CTV that executes a quasiperiodic motion z(t) does not receive Φ(x,y), but rather an Effective Incident Fluence EIF(x,y). We numerically evaluate the EIF(x,y) from a given DMLC file by a coordinate transformation to the Target's Eye View (TEV). In the TEV coordinate system, the CTV itself is stationary, and the MLC is seen to execute a motion -z(t) that is superimposed on the DMLC motion. The resulting EIF(x,y) is input

  18. Fee Increases and Target Income Hypothesis: Data from Quebec on Physicians' Compensation and Service Volumes

    Science.gov (United States)

    Contandriopoulos, Damien; Perroux, Mélanie

    2013-01-01

    Recent years have witnessed important public investments in physicians' compensation across Canada. The current paper uses data from Quebec to assess the impact of those investments on the volumes of services provided to the population. While total physician compensation costs, average physician compensation and average unit cost per service all rose extremely fast, the total number of services, number of services per capita and average number of services per physician either stagnated or declined. This pattern is compatible with the economic target income hypothesis and raises important policy questions. PMID:24359715

  19. Clinical target volume delineation in glioblastomas: pre-operative versus post-operative/pre-radiotherapy MRI

    Science.gov (United States)

    Farace, P; Giri, M G; Meliadò, G; Amelio, D; Widesott, L; Ricciardi, G K; Dall'Oglio, S; Rizzotti, A; Sbarbati, A; Beltramello, A; Maluta, S; Amichetti, M

    2011-01-01

    Objectives Delineation of clinical target volume (CTV) is still controversial in glioblastomas. In order to assess the differences in volume and shape of the radiotherapy target, the use of pre-operative vs post-operative/pre-radiotherapy T1 and T2 weighted MRI was compared. Methods 4 CTVs were delineated in 24 patients pre-operatively and post-operatively using T1 contrast-enhanced (T1PRECTV and T1POSTCTV) and T2 weighted images (T2PRECTV and T2POSTCTV). Pre-operative MRI examinations were performed the day before surgery, whereas post-operative examinations were acquired 1 month after surgery and before chemoradiation. A concordance index (CI) was defined as the ratio between the overlapping and composite volumes. Results The volumes of T1PRECTV and T1POSTCTV were not statistically different (248 ± 88 vs 254 ± 101), although volume differences >100 cm3 were observed in 6 out of 24 patients. A marked increase due to tumour progression was shown in three patients. Three patients showed a decrease because of a reduced mass effect. A significant reduction occurred between pre-operative and post-operative T2 volumes (139 ± 68 vs 78 ± 59). Lack of concordance was observed between T1PRECTV and T1POSTCTV (CI = 0.67 ± 0.09), T2PRECTV and T2POSTCTV (CI = 0.39 ± 0.20) and comparing the portion of the T1PRECTV and T1POSTCTV not covered by that defined on T2PRECTV images (CI = 0.45 ± 0.16 and 0.44 ± 0.17, respectively). Conclusion Using T2 MRI, huge variations can be observed in peritumoural oedema, which are probably due to steroid treatment. Using T1 MRI, brain shifts after surgery and possible progressive enhancing lesions produce substantial differences in CTVs. Our data support the use of post-operative/pre-radiotherapy T1 weighted MRI for planning purposes. PMID:21045069

  20. Residual tumor after neoadjuvant chemoradiation outside the radiation therapy target volume : a new prognostic factor for survival in esophageal cancer

    NARCIS (Netherlands)

    Muijs, Christina; Smit, Justin; Karrenbeld, Arend; Beukema, Jannet C.; Mul, Veronique; van Dam, Go; Hospers, Geke; Kluin, Phillip; Langendijk, Johannes; Plukker, John

    2014-01-01

    PURPOSE/OBJECTIVE(S): The aim of this study was to analyze the accuracy of gross tumor volume (GTV) delineation and clinical target volume (CTV) margins for neoadjuvant chemoradiation therapy (neo-CRT) in esophageal carcinoma at pathologic examination and to determine the impact on survival. METHODS

  1. Residual Tumor After Neoadjuvant Chemoradiation Outside the Radiation Therapy Target Volume : A New Prognostic Factor for Survival in Esophageal Cancer

    NARCIS (Netherlands)

    Muijs, Christina; Smit, Justin; Karrenbeld, Arend; Beukema, J.C.; Mul, Veronique; van Dam, Go; Hospers, Geke; Kluin, Phillip; Langendijk, Johannes; Plukker, John

    2014-01-01

    Purpose/Objective(s): The aim of this study was to analyze the accuracy of gross tumor volume (GTV) delineation and clinical target volume (CTV) margins for neoadjuvant chemoradiation therapy (neo-CRT) in esophageal carcinoma at pathologic examination and to determine the impact on survival. Methods

  2. MRI-assisted specification/localization of target volumes. Aspects of quality control

    International Nuclear Information System (INIS)

    The transportation of MRI information on tumor extension into CT-based radiation therapy planning is desirable for several reasons. MRI's better contrast resolution is usually considered the most important, as it leads to a more exact definition of target volumes. Unlike diagnostic imaging, where a certain margin of error in depiction of tumor extension seems acceptable, radiation therapy planning makes it absolutely necessary, that the contents of very MR pixel (or voxel) correspond exactly to the corresponding area in the patient examined. This exact correspondence may be disturbed by a variety of influencing factors. Objects like various implants may lead to the most severe image distortions and - even worse - contrast alterations, some of which are not easily visible on the slices which are used for target volume definition. Additionally, MR images may have intrinsic faults which are able to change the correspondence between the voxel and the part of the patient's body it represents. Quality control has therefore to ensure that parameters like slice thickness are correct and kept constant by the imager. Image fusion may then be used to transfer MR information on tumor extension into the CT data. Electron density distribution provided by CT then allows for treatment planning. Implanted markers may then be used to ensure exact correspondence between the examined parts of the patient's body and the representing pixel or voxel. Care should be taken that landmarks themselves do not influence this relationship. (orig.)

  3. Radial displacement of clinical target volume in node negative head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Wan; Wu, Hong Gyun; Song, Sang Hyuk; Kim, Jung In [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2012-03-15

    To evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H and N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers. Three node-negative H and N cancer patients and fi ve healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified. The mean radial displacements were 2.26 ({+-}1.03) mm in the control group and 3.05 ({+-}1.97) in the H and N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups. This study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

  4. Dosimetric Advantages of Midventilation Compared With Internal Target Volume for Radiation Therapy of Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lens, Eelco, E-mail: e.lens@amc.uva.nl; Horst, Astrid van der; Versteijne, Eva; Tienhoven, Geertjan van; Bel, Arjan

    2015-07-01

    Purpose: The midventilation (midV) approach can be used to take respiratory-induced pancreatic tumor motion into account during radiation therapy. In this study, the dosimetric consequences for organs at risk and tumor coverage of using a midV approach compared with using an internal target volume (ITV) were investigated. Methods and Materials: For each of the 18 patients, 2 treatment plans (25 × 2.0 Gy) were created, 1 using an ITV and 1 using a midV approach. The midV dose distribution was blurred using the respiratory-induced motion from 4-dimensional computed tomography. The resulting planning target volume (PTV) coverage for this blurred dose distribution was analyzed; PTV coverage was required to be at least V{sub 95%} >98%. In addition, the change in PTV size and the changes in V{sub 10Gy}, V{sub 20Gy}, V{sub 30Gy}, V{sub 40Gy}, D{sub mean} and D{sub 2cc} for the stomach and for the duodenum were analyzed; differences were tested for significance using the Wilcoxon signed-rank test. Results: Using a midV approach resulted in sufficient target coverage. A highly significant PTV size reduction of 13.9% (P<.001) was observed. Also, all dose parameters for the stomach and duodenum, except the D{sub 2cc} of the duodenum, improved significantly (P≤.002). Conclusions: By using the midV approach to account for respiratory-induced tumor motion, a significant PTV reduction and significant dose reductions to the stomach and to the duodenum can be achieved when irradiating pancreatic tumors.

  5. Anatomo-clinical target volumes (GTV and CTV) in radiotherapy; Volumes cibles anatomocliniques (GTV et CTV) en radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Kantor, G. [Institut Bergonie, Universite Victor-Segalen, Dept. de Radiotherapie, Centre Regional de Lutte Contre le Cancer, 33 - Bordeaux (France); Halimi, P. [Hopital Europeen Georges-Pompidou, Service de Radiologie, Faculte de Medecine Paris-5, 75 - Paris (France)

    2005-06-15

    In this issue will be tackled the development of tools (multi modules scanner and images fusion) and the analysis of volumes for cerebral tumors (head and neck). It seemed necessary to update this theme because of the ever more widespread use of conformation radiotherapy and new constraints of volumes definitions brought by radiotherapy with intensity modulation. (N.C.)

  6. An analytic solution for calculating the beam intensity profiles useful to irradiate target volumes with bi-concave outlines

    Energy Technology Data Exchange (ETDEWEB)

    De Neve, W.; Derycke, S.; De Wagter, C. [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde

    1995-12-01

    A heuristic planing procedure allowing to obtain a 3-dimensional conformal dose distribution in radiotherapy for target volumes with a bi-concave or multi-concave shape has been developed. The described method is tested on a phantom simulating a pelvic target, described by Brahme.

  7. Evaluation of potential internal target volume of liver tumors using cine-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Akino, Yuichi, E-mail: akino@radonc.med.osaka-u.ac.jp [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka 5650871, Japan and Miyakojima IGRT Clinic, Miyakojima-ku, Osaka 5340021 (Japan); Oh, Ryoong-Jin; Masai, Norihisa; Shiomi, Hiroya; Inoue, Toshihiko [Miyakojima IGRT Clinic, Miyakojima-ku, Osaka 5340021 (Japan)

    2014-11-01

    Purpose: Four-dimensional computed tomography (4DCT) is widely used for evaluating moving tumors, including lung and liver cancers. For patients with unstable respiration, however, the 4DCT may not visualize tumor motion properly. High-speed magnetic resonance imaging (MRI) sequences (cine-MRI) permit direct visualization of respiratory motion of liver tumors without considering radiation dose exposure to patients. Here, the authors demonstrated a technique for evaluating internal target volume (ITV) with consideration of respiratory variation using cine-MRI. Methods: The authors retrospectively evaluated six patients who received stereotactic body radiotherapy (SBRT) to hepatocellular carcinoma. Before acquiring planning CT, sagittal and coronal cine-MRI images were acquired for 30 s with a frame rate of 2 frames/s. The patient immobilization was conducted under the same condition as SBRT. Planning CT images were then acquired within 15 min from cine-MRI image acquisitions, followed by a 4DCT scan. To calculate tumor motion, the motion vectors between two continuous frames of cine-MRI images were calculated for each frame using the pyramidal Lucas–Kanade method. The target contour was delineated on one frame, and each vertex of the contour was shifted and copied onto the following frame using neighboring motion vectors. 3D trajectory data were generated with the centroid of the contours on sagittal and coronal images. To evaluate the accuracy of the tracking method, the motion of clearly visible blood vessel was analyzed with the motion tracking and manual detection techniques. The target volume delineated on the 50% (end-exhale) phase of 4DCT was translated with the trajectory data, and the distribution of the occupancy probability of target volume was calculated as potential ITV (ITV {sub Potential}). The concordance between ITV {sub Potential} and ITV estimated with 4DCT (ITV {sub 4DCT}) was evaluated using the Dice’s similarity coefficient (DSC). Results

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

    Science.gov (United States)

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

    2014-02-01

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

  9. Gross tumor volume (GTV) and clinical target volume (CTV) for radiation therapy of benign skull base tumours; Volume tumoral macroscopique (GTV) et volume-cible anatomoclinique (CTV) dans la radiotherapie des tumeurs benignes de la base du crane

    Energy Technology Data Exchange (ETDEWEB)

    Maire, J.P. [Centre Hospitalier Universitaire de Bordeaux, Hopital Saint Andre, Service d' Oncologie Radiotherapie, 33 - Bordeaux (France); Liguoro, D.; San Galli, F. [Centre Hospitalier Universitaire de Bordeaux, Hopital Saint Andre, Service de Neurochirurgie A, 33 - Bordeaux (France)

    2001-10-01

    Skull base tumours represent a out 35 to 40% of all intracranial tumours. There are now many reports in the literature confirming the fact that about 80 to 90% of such tumours are controlled with fractionated radiotherapy. Stereotactic and 3-dimensional treatment planning techniques increase local control and central nervous system tolerance. Definition of the gross tumor volume (GTV) is generally easy with currently available medical imaging systems and computers for 3-dimensional dosimetry. The definition of the clinical target volume (CTV) is more difficult to appreciate: it is defined from the CTV plus a margin, which depends on the histology and anterior therapeutic history of the tumour. It is important to take into account the visible tumour and its possible extension pathways (adjacent bone, holes at the base of skull) and/or an anatomic region (sella turcica + adjacent cavernous sinus). It is necessary to evaluate these volumes with CT Scan and MRI to appreciate tumor extension in a 3-dimensional approach, in order to reduce the risk of marginal recurrences. The aim of this paper is to discuss volume definition as a function of tumour site and tumour type to be irradiated. (authors)

  10. Volume Transmission in Central Dopamine and Noradrenaline Neurons and Its Astroglial Targets.

    Science.gov (United States)

    Fuxe, Kjell; Agnati, Luigi F; Marcoli, Manuela; Borroto-Escuela, Dasiel O

    2015-12-01

    Already in the 1960s the architecture and pharmacology of the brainstem dopamine (DA) and noradrenaline (NA) neurons with formation of vast numbers of DA and NA terminal plexa of the central nervous system (CNS) indicated that they may not only communicate via synaptic transmission. In the 1980s the theory of volume transmission (VT) was introduced as a major communication together with synaptic transmission in the CNS. VT is an extracellular and cerebrospinal fluid transmission of chemical signals like transmitters, modulators etc. moving along energy gradients making diffusion and flow of VT signals possible. VT interacts with synaptic transmission mainly through direct receptor-receptor interactions in synaptic and extrasynaptic heteroreceptor complexes and their signaling cascades. The DA and NA neurons are specialized for extrasynaptic VT at the soma-dendrtitic and terminal level. The catecholamines released target multiple DA and adrenergic subtypes on nerve cells, astroglia and microglia which are the major cell components of the trophic units building up the neural-glial networks of the CNS. DA and NA VT can modulate not only the strength of synaptic transmission but also the VT signaling of the astroglia and microglia of high relevance for neuron-glia interactions. The catecholamine VT targeting astroglia can modulate the fundamental functions of astroglia observed in neuroenergetics, in the Glymphatic system, in the central renin-angiotensin system and in the production of long-distance calcium waves. Also the astrocytic and microglial DA and adrenergic receptor subtypes mediating DA and NA VT can be significant drug targets in neurological and psychiatric disease. PMID:25894681

  11. Radiotherapy of large target volumes in Hodgkin's lymphoma: normal tissue sparing capability of forward IMRT versus conventional techniques

    OpenAIRE

    Conson Manuel; Magliulo Mario; Liuzzi Raffaele; Cella Laura; Camera Luigi; Salvatore Marco; Pacelli Roberto

    2010-01-01

    Abstract Background This paper analyses normal tissue sparing capability of radiation treatment techniques in Hodgkin's lymphoma with large treatment volume. Methods 10 patients with supradiaphragmatic Hodgkin's lymphoma and planning target volume (PTV) larger than 900 cm3 were evaluated. Two plans were simulated for each patient using 6 MV X-rays: a conventional multi-leaf (MLC) parallel-opposed (AP-PA) plan, and the same plan with additional MLC shaped segments (forward planned intensity mo...

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

    International Nuclear Information System (INIS)

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

  13. Target volume delineation and field setup. A practical guide for conformal and intensity-modulated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nancy Y. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States). Radiation Oncology; Lu, Jiade J. (eds.) [National Univ. Health System, Singapore (Singapore). Dept. of Radiation Oncology; National Univ. of Singapore (Singapore). Dept. of Medicine

    2013-03-01

    Practical handbook on selection and delineation of tumor volumes and fields for conformal radiation therapy, including IMRT. Helpful format facilitating use on a step-by-step basis in daily practice. Designed to ensure accurate coverage of commonly encountered tumors along their routes of spread. This handbook is designed to enable radiation oncologists to appropriately and confidently delineate tumor volumes/fields for conformal radiation therapy, including intensity-modulated radiation therapy (IMRT), in patients with commonly encountered cancers. The orientation of this handbook is entirely practical, in that the focus is on the illustration of clinical target volume (CTV) delineation for each major malignancy. Each chapter provides guidelines and concise knowledge on CTV selection for a particular disease, explains how the anatomy of lymphatic drainage shapes the selection of the target volume, and presents detailed illustrations of volumes, slice by slice, on planning CT images. While the emphasis is on target volume delineation for three-dimensional conformal therapy and IMRT, information is also provided on conventional radiation therapy field setup and planning for certain malignancies for which IMRT is not currently suitable.

  14. Optimization of radiotherapy to target volumes with concave outlines: target-dose homogenization and selective sparing of critical structures by constrained matrix inversion

    Energy Technology Data Exchange (ETDEWEB)

    Colle, C.; Van den Berge, D.; De Wagter, C.; Fortan, L.; Van Duyse, B.; De Neve, W.

    1995-12-01

    The design of 3D-conformal dose distributions for targets with concave outlines is a technical challenge in conformal radiotherapy. For these targets, it is impossible to find beam incidences for which the target volume can be isolated from the tissues at risk. Commonly occurring examples are most thyroid cancers and the targets located at the lower neck and upper mediastinal levels related to some head and neck. A solution to this problem was developed, using beam intensity modulation executed with a multileaf collimator by applying a static beam-segmentation technique. The method includes the definition of beam incidences and beam segments of specific shape as well as the calculation of segment weights. Tests on Sherouse`s GRATISTM planning system allowed to escalate the dose to these targets to 65-70 Gy without exceeding spinal cord tolerance. Further optimization by constrained matrix inversion was investigated to explore the possibility of further dose escalation.

  15. Microinvasion of liver metastases from colorectal cancer: predictive factors and application for determining clinical target volume

    International Nuclear Information System (INIS)

    This study evaluates the microscopic characteristics of liver metastases from colorectal cancer (LMCRC) invasion and provides a reference for expansion from gross tumor volume (GTV) to clinical targeting volume (CTV). Data from 129 LMCRC patients treated by surgical resection at our hospital between January 2008 and September 2009 were collected for study. Tissue sections used for pathology and clinical data were reviewed. Patient information used for the study included gender, age, original tumor site, number of tumors, tumor size, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 199 (CA199), synchronous or metachronous liver metastases, and whether patients received chemotherapy. The distance of liver microinvasion from the tumor boundary was measured microscopically by two senior pathologists. Of 129 patients evaluated, 81 (62.8 %) presented microinvasion distances from the tumor boundary ranging between 1.0 − 7.0 mm. A GTV-to-CTV expansion of 5, 6.7, or 7.0 mm was required to provide a 95, 99, or 100 % probability, respectively, of obtaining clear resection margins by microscopic observation. The extent of invasion was not related to gender, age, synchronous or metachronous liver metastases, tumor size, CA199 level, or chemotherapy. The extent of invasion was related to original tumor site, CEA level, and number of tumors. A scoring system was established based on the latter three positive predictors. Using this system, an invasion distance less than 3 mm was measured in 93.4 % of patients with a score of ≤1 point, but in only 85.7 % of patients with a score of ≤2 points. The extent of tumor invasion in our LMCRC patient cohort correlated with original tumor site, CEA level, and number of tumors. These positive predictors may potentially be used as a scoring system for determining GTV-to-CTV expansion

  16. Sphaeropsidin A shows promising activity against drug-resistant cancer cells by targeting regulatory volume increase

    Science.gov (United States)

    Mathieu, Véronique; Chantôme, Aurélie; Lefranc, Florence; Cimmino, Alessio; Miklos, Walter; Paulitschke, Verena; Mohr, Thomas; Maddau, Lucia; Kornienko, Alexander; Berger, Walter; Vandier, Christophe; Evidente, Antonio; Delpire, Eric; Kiss, Robert

    2016-01-01

    Despite the recent advances in the treatment of tumors with intrinsic chemotherapy resistance, such as melanoma and renal cancers, their prognosis remains poor and new chemical agents with promising activity against these cancers are urgently needed. Sphaeropsidin A, a fungal metabolite whose anticancer potential had previously received little attention, was isolated from Diplodia cupressi and found to display specific anticancer activity in vitro against melanoma and kidney cancer subpanels in the National Cancer Institute (NCI) 60-cell line screen. The NCI data revealed a mean LC50 of ca. 10 μM and a cellular sensitivity profile that did not match that of any other agent in the 765,000 compound database. Subsequent mechanistic studies in melanoma and other multidrug-resistant in vitro cancer models showed that sphaeropsidin A can overcome apoptosis as well as multidrug resistance by inducing a marked and rapid cellular shrinkage related to the loss of intracellular Cl− and the decreased HCO3− concentration in the culture supernatant. These changes in ion homeostasis and the absence of effects on the plasma membrane potential were attributed to the sphaeropsidin A-induced impairment of regulatory volume increase (RVI). Preliminary results also indicate that depending on the type of cancer, the sphaeropsidin A effects on RVI could be related to Na–K–2Cl electroneutral cotransporter or Cl−/HCO3− anion exchanger(s) targeting. This study underscores the modulation of ion-transporter activity as a promising therapeutic strategy to combat drug-resistant cancers and identifies the fungal metabolite, sphaeropsidin A, as a lead to develop anticancer agents targeting RVI in cancer cells. PMID:25868554

  17. Gross tumor volume and clinical target volume in prostate cancer: How do satellites relate to the index lesion

    International Nuclear Information System (INIS)

    Purpose: There is an increasing interest for dose differentiation in prostate radiotherapy. The purpose of our study was to analyze the spatial distribution of tumor satellites inside the prostate. Methods and materials: 61 prostatectomy specimens were stained with H&E. Tumor regions were delineated by the uro-pathologist. Volumes, distances and cell densities of all delineated tumor regions were measured and further analyzed. Results: Multifocal disease was seen in 84% of the patients. The median number of tumor foci was 3. The median distance between the index lesion and the satellites was 1.0 cm, with a maximum of 4.4 cm. The index lesions accounted for 88% of the total tumor volume. The contribution of tumor foci < 0.1 cm3 to the total tumor volume was 2%. The median cell density of the index lesion and all satellites, regardless of size, were significantly higher than that of the prostate. Conclusions: Satellites do not appear in a limited margin around the index lesion (GTV). Consequently, a fixed CTV margin would not effectively cover all satellites. Thus if the aim is to treat all tumor foci, the entire prostate gland should be considered CTV

  18. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer

    International Nuclear Information System (INIS)

    Background and purpose: Delineation of clinical target volumes (CTVs) is a weak link in radiation therapy (RT), and large inter-observer variation is seen in breast cancer patients. Several guidelines have been proposed, but most result in larger CTVs than based on conventional simulator-based RT. The aim was to develop a delineation guideline obtained by consensus between a broad European group of radiation oncologists. Material and methods: During ESTRO teaching courses on breast cancer, teachers sought consensus on delineation of CTV through dialogue based on cases. One teacher delineated CTV on CT scans of 2 patients, followed by discussion and adaptation of the delineation. The consensus established between teachers was sent to other teams working in the same field, both locally and on a national level, for their input. This was followed by developing a broad consensus based on discussions. Results: Borders of the CTV encompassing a 5 mm margin around the large veins, running through the regional lymph node levels were agreed, and for the breast/thoracic wall other vessels were pointed out to guide delineation, with comments on margins for patients with advanced breast cancer. Conclusion: The ESTRO consensus on CTV for elective RT of breast cancer, endorsed by a broad base of the radiation oncology community, is presented to improve consistency

  19. The ADVANCE project: Formal evaluation of the targeted deployment. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    The Advanced Driver and Vehicle Advisory Navigation ConcEpt (ADVANCE) was an invehicle advanced traveler information system (ATIS) that operated in the northwest suburbs of Chicago, Illinois. It was designed to provide origin-destination shortest-time route guidance to a vehicle based on (a) an on-board static (fixed) data base of average network link travel times by time of day, combined as available and appropriate with (b) dynamic (real-time) information on traffic conditions provided by radio frequency (RF) communications to and from a traffic information center (TIC). Originally conceived in 1990 as a major project that would have installed 3,000 to 5,000 route guidance units in privately owned vehicles throughout the test area, ADVANCE was restructured in 1995 as a {open_quotes}targeted deployment,{close_quotes} in which approximately 80 vehicles were to be equipped with the guidance units - Mobile Navigation Assistants (MNAs) - to be in full communication with the TIC while driving the ADVANCE test area road system. Volume one consists of the evaluation managers overview report, and several appendices containing test results.

  20. Patterns of relapse following radiotherapy for differentiated thyroid cancer: Implication for target volume delineation

    International Nuclear Information System (INIS)

    Introduction: Post-operative residual disease in differentiated thyroid cancer is an indication for external beam radiotherapy (EBRT) especially if there is poor radioiodine uptake by the residual disease. There are no standardized guidelines or consensus in target delineation for radiotherapy in thyroid cancer. Aims: To determine the pattern of recurrence in patients with well differentiated thyroid cancer who received adjuvant or definitive radiotherapy as well as radioiodine ablation following surgery or biopsy with a view to better defining future target volume delineation for radiotherapy. Materials and methods: Forty-nine patients with differentiated thyroid cancer received radical external beam radiotherapy and radioiodine ablation (3.5 GBq) following thyroidectomy or biopsy between 1990 and 2000. Nineteen patients had macroscopic residual (11) or inoperable disease (8), whilst 30 patients had clear (5) or microscopic positive resection margin (24), and 1 patient the resection margin status was unknown. All the patients were deemed high risk for local recurrence or progressive disease. The thyroid bed and regional nodes were irradiated using two radiotherapy techniques: (1) non co-planar lateral fields (NCLF) in coronal plane using 6 MV photons to a dose of 45-50 Gy in 16 fractions over 22 days and (2) anterior-posterior parallel pair of 6 MV photons to a dose of 40-42.5 Gy in 16 fractions over 22 days. There was no attempt to irradiate the lymph nodes in that part of the anterior and posterior mediastinum extending from the brachiocephalic veins to the carina. Results: The median follow-up was 5.4 years (range 0.9-12.4 years). The actuarial 5-year cause-specific survival and local control for the whole group was 75.7% and 81.4%, respectively. Of the 4 patients with mediastinal recurrence, all had neck recurrences and two had distant metastases. All the medisastinal recurrences occurred in superior mediastinum (level VII) and all were treated with NCLF in

  1. Consequences of additional use of PET information for target volume delineation and radiotherapy dose distribution for esophageal cancer

    NARCIS (Netherlands)

    Muijs, Christina T.; Schreurs, Liesbeth M.; Busz, Dianne M.; Beukema, Jannet C.; van der Borden, Arnout J.; Pruim, Jan; Van der Jagt, Eric J.; Plukker, John Th.; Langendijk, Johannes A.

    2009-01-01

    Background and purpose. To determine the consequences of target volume (TV) modifications, based on the additional use of PET information, on radiation planning, assuming PET/CT-imaging represents the title extent of the tumour Materials and methods. For 21 patients with esophageal cancer, two separ

  2. Use of volume-targeted non-invasive bilevel positive airway pressure ventilation in a patient with amyotrophic lateral sclerosis,

    Directory of Open Access Journals (Sweden)

    Montserrat Diaz-Abad

    2014-08-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a progressive neurodegenerative disease in which most patients die of respiratory failure. Although volume-targeted non-invasive bilevel positive airway pressure (BPAP ventilation has been studied in patients with chronic respiratory failure of various etiologies, its use in ALS has not been reported. We present the case of a 66-year-old woman with ALS and respiratory failure treated with volume-targeted BPAP ventilation for 15 weeks. Weekly data downloads showed that disease progression was associated with increased respiratory muscle weakness, decreased spontaneous breathing, and increased use of non-invasive positive pressure ventilation, whereas tidal volume and minute ventilation remained relatively constant.

  3. Clinical study on the changes of the tumor target volume and organs at risk in helical tomotherapy for nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    LU Na; FENG Lin-chun; CAI Bo-ning; HOU Jun; WANG Yun-lai; XIE Chuan-bin

    2012-01-01

    Background Helical tomotherapy (HT) is a new image-guided intensity-modulated radiation therapy (IMRT).The aim of this study was to evaluate the changes in the target volume and organs at risk (OARs) of patients with nasopharyngeal carcinoma (NPC) during helical tomotherapy.Methods Forty-three patients with NPC and treated via HT from March 2008 to January 2010 were reviewed retrospectively.Repeated CT scanning and plan adaptation were conducted at the 20th fraction during radiotherapy.The volumetric differences between the two scans were evaluated for nasopharyngeal tumor and retro- pharyngeal lymph nodes (GTVnx),neck lymph nodes (GTVnd),and parotid glands,as well as the axial diameter of the head.Results The median interval between the two scans was 25 days (23-28 days).The volumetric decrease in GTVnx was 30.1% (median,29.8%) and in GTVnd 41.6% (median,45.9%).The variation in the GTVnd volume was correlated with the weight loss of the patient.The volume of the left parotid gland decreased by 35.5% (median,33.4%) and of the right parotid glands decreased by 36.8% (median,33.5%).The axial diameter of the head decreased by 9.39% (median,9.1%).Conclusions The target volume and OARs of patients with NPC varied considerably during HT.These changes may have potential dosimetric effects on the target volume and/or OARs and influence the clinical outcome.Repeated CT scanning and replanning during the HT for NPC patients with a large target volume or an obvious weight loss are recommended.

  4. Locoregional extension patterns of nasopharyngeal carcinoma and suggestions for clinical target volume delineation

    Institute of Scientific and Technical Information of China (English)

    Wen-Fei Li; Jun Ma; Ying Sun; Mo Chen; Ling-Long Tang; Li-Zhi Liu; Yan-Ping Mao; Lei Chen; Guan-Qun Zhou; Li Li

    2012-01-01

    Clinical target volume (CTV) delineation is crucial for tumor control and normal tissue protection.This study aimed to define the Iocoregional extension patterns of nasopharyngeal carcinoma (NPC) and to improve CTV delineation.Magnetic resonance imaging scans of 2366 newly diagnosed NPC patients were reviewed.According to incidence rates of tumor invasion,the anatomic sites surrounding the nasopharynx were classified into high-risk (>30%),medium-risk (5%-30%),and low-risk (<5%) groups.The lymph node (LN) level was determined according to the Radiation Therapy Oncology Group guidelines,which were further categorized into the upper neck (retropharyngeal region and level Ⅱ),middle neck (levels Ⅲ and Va),and lower neck (levels IV and Vb and the supraclavicular fossa).The high-risk anatomic sites were adjacent to the nasopharynx,whereas those at medium-or low-risk were separated from the nasopharynx.If the high-risk anatomic sites were involved,the rates of tumor invasion into the adjacent medium-risk sites increased; if not,the rates were significantly lower (P < 0.01).Among the 1920 (81.1%) patients with positive LN,the incidence rates of LN metastasis in the upper,middle,and lower neck were 99.6%,30.2%,and 7.2%,respectively,and skip metastasis happened in only 1.2% of patients.In the 929 patients who had unilateral upper neck involvement,the rates of contralateral middle neck and lower neck involvement were 1.8% and 0.4%,respectively.Thus,local disease spreads stepwise from proximal sites to distal sites,and LN metastasis spreads from the upper neck to the lower neck.Individualized CTV delineation for NPC may be feasible.

  5. The impact of Gross Tumor Volume (GTV) and Clinical Target Volume (CTV) definition on the total accuracy in radiotherapy. Theoretical aspects and practical experiences

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, E.; Hess, C.F. [Dept. of Radiation Therapy, Univ. of Goettingen (Germany)

    2003-01-01

    Aim: To evaluate the impact of interobserver variability in the contouring of gross tumor volumes (GTVs) and clinical target volumes (CTVs) on the global geometric accuracy in radiation therapy. Material and Methods: In a review of the currently available literature, the magnitude of interobserver variability is analyzed, causes and consequences are discussed. Uncertainties due to inconsistencies in contouring are related to other sources of geometric errors, particularly patient positioning and organ motion. Results: Interobserver variability is a major - for some tumor locations probably the largest - factor contributing to geometric inaccuracy. Causes are multifactorial and include image- and observer-related factors, such as the subjective interpretation of image information. Conclusion: Consequences to reduce interobserver variability are proposed, among others the selection of adequate imaging modalities, intensified radiologic training, and the use of telecommunication tools. (orig.)

  6. Impact of 18F-FDG PET/CT on target volume delineation in recurrent or residual gynaecologic carcinoma

    OpenAIRE

    Vees, Hansjoerg; Casanova, Nathalie; Zilli, Thomas; Imperiano, Hestia; Ratib, Osman; Popowski, Youri; Wang, Hui; Zaidi, Habib; Miralbell, Raymond

    2012-01-01

    Background To evaluate the impact of 18F-FDG PET/CT on target volume delineation in gynaecological cancer. Methods F-FDG PET/CT based RT treatment planning was performed in 10 patients with locally recurrent (n = 5) or post-surgical residual gynaecological cancer (n = 5). The gross tumor volume (GTV) was defined by 4 experienced radiation oncologists first using contrast enhanced CT (GTVCT) and secondly using the fused 18F-FDG PET/CT datasets (GTVPET/CT). In addition, the GTV was delineated u...

  7. Planning target volume (PTV) definition and its effects in the radiotherapy; Definicao do volume de planejamento do alvo (PTV) e seu efeito na radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Poli, Maria Esmeralda Ramos

    2007-07-01

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

  8. Prospective comparative evaluation of planning target volume margin for brain intensity modulated radiotherapy utilizing hybrid online imaging modalities

    OpenAIRE

    Sayan Paul; Shilpi Roy; Shaleen Agrawal; Anusheel Munshi; Kanan Jassal; Tharmar Ganesh; Saneg Krishnankutty; Jeen Soundra Pandian Sathiya; Bidhu Kalyan Mohanti

    2015-01-01

    Background: A new advancement in daily monitoring of patient positioning is the use of hybrid technologies where two separate online imaging modalities are integrated to achieve precise treatment delivery. Our center has a set-up that integrates Elekta Linear accelerator device (EPID) with BrainLAB ExacTrac imaging for the first time in the world. We calculated planning target volume (PTV) margin for brain radiotherapy with thermoplastic mask immobilization with conventional EPID and BrainLAB...

  9. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

    OpenAIRE

    Wang, Wei; LI, JIANBIN; Zhang, Yingjie; SHAO, QIAN; Xu, Min; Fan, Tingyong; Wang, Jinzhi

    2016-01-01

    Wei Wang, Jianbin Li, Yingjie Zhang, Qian Shao, Min Xu, Tingyong Fan, Jinzhi Wang Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Shandong, People’s Republic of China Background and purpose: To investigate the definition of planning target volumes (PTVs) based on four-dimensional computed tomography (4DCT) compared with conventional PTV definition and PTV definition using asymmetrical margins for t...

  10. Accelerated particle-based target capture--the roles of volume transport and near-surface alignment.

    Science.gov (United States)

    van Reenen, Alexander; de Jong, Arthur M; Prins, Menno W J

    2013-02-01

    The upcoming generations of high-sensitive and miniaturized biosensing systems need target capture methods that are as efficient and as rapid as possible, with targets ranging from molecules to cells. Capture of the targets can be achieved using particles coated with affinity molecules, but there are still fundamental questions as to the processes that limit the association rates. In this paper we quantify and compare the reaction rates of particle-based target capture with different types of actuation, namely (i) passive thermal transport, (ii) fluid agitation by vortex mixing, and (iii) actively rotating particles. In the experiments, we use fluorescent nanoparticles as targets which are biochemically captured by magnetic microparticles, and the capture efficiency is quantified using fluorescence microscopy with single target resolution. The data unravel the contributions of volume transport, near-surface alignment, and the chemical reaction to the overall rate constant of association. Vortex mixing versus passive transport gives an increase of the reaction rate constant by more than an order of magnitude, implying that the encounter frequency as well as the near-surface alignment probability are increased. The importance of near-surface alignment is underscored by the data of active particle rotation; the binding probability per encounter is 4-fold enhanced on rotating capture particles. We discuss the implications of our results for different biological systems and for the development of novel actuation methods in particle-based target capture. PMID:23297682

  11. Performance of an atlas-based autosegmentation software for delineation of target volumes for radiotherapy of breast and anorectal cancer

    International Nuclear Information System (INIS)

    Background and purpose: To validate atlas-based autosegmentation for contouring breast/anorectal targets. Methods and materials: ABAS uses atlases with defined CTVs as template cases to automatically delineate target volumes in other patient CT-datasets. Results are compared with manually contoured CTVs of breast/anorectal cancer according to RTOG-guidelines. The impact of using specific atlases matched to individual patient geometry was evaluated. Results were quantified by analyzing Dice Similarity Coefficient (DSC), logit(DSC) and Percent Overlap (PO). DSC >0.700 and logit(DSC) >0.847 are acceptable. In addition a new algorithm (STAPLE) was evaluated. Results: ABAS produced good results for the CTV of breast/anorectal cancer targets. Delineation of inguinal lymphatic drainage, however, was insufficient. Results for breast CTV were (DSC: 0.86–0.91 ([0, 1]), logit(DSC): 1.82–2.36 ([−∞, ∞]), PO: 75.5–82.89%) and for anorectal CTVA (DSC: 0.79–0.85, logit(DSC): 1.40–1.77, PO: 68–73.67%). Conclusions: ABAS produced satisfactory results for these clinical target volumes that are defined by more complex tissue interface geometry, thus streamlining and facilitating the radiotherapy workflow which is essential to face increasing demand and limited resources. STAPLE improved contouring outcome. Small target volumes not clearly defined are still to be delineated manually. Based on these results, ABAS has been clinically introduced for precontouring of CTVs/OARs.

  12. Radiotherapy of large target volumes in Hodgkin's lymphoma: normal tissue sparing capability of forward IMRT versus conventional techniques

    Directory of Open Access Journals (Sweden)

    Conson Manuel

    2010-05-01

    Full Text Available Abstract Background This paper analyses normal tissue sparing capability of radiation treatment techniques in Hodgkin's lymphoma with large treatment volume. Methods 10 patients with supradiaphragmatic Hodgkin's lymphoma and planning target volume (PTV larger than 900 cm3 were evaluated. Two plans were simulated for each patient using 6 MV X-rays: a conventional multi-leaf (MLC parallel-opposed (AP-PA plan, and the same plan with additional MLC shaped segments (forward planned intensity modulated radiation therapy, FPIMRT. In order to compare plans, dose-volume histograms (DVHs of PTV, lungs, heart, spinal cord, breast, and thyroid were analyzed. The Inhomogeneity Coefficient (IC, the PTV receiving 95% of the prescription dose (V95, the normal tissue complication probability (NTCP and dose-volume parameters for the OARs were determined. Results the PTV coverage was improved (mean V95AP-PA = 95.9 and ICAP-PA = 0.4 vs. V95FPIMRT = 96.8 and ICFPIMRT = 0.31, p ≤ 0.05 by the FPIMRT technique compared to the conventional one. At the same time, NTCPs of lung, spinal cord and thyroid, and the volume of lung and thyroid receiving ≥ 30 Gy resulted significantly reduced when using the FPIMRT technique. Conclusions The FPIMRT technique can represent a very useful and, at the same time, simple method for improving PTV conformity while saving critical organs when large fields are needed as in Hodgkin's lymphoma.

  13. Recurrence pattern of squamous cell carcinoma in the midthoracic esophagus: implications for the clinical target volume design of postoperative radiotherapy

    Directory of Open Access Journals (Sweden)

    Wang X

    2016-10-01

    Full Text Available Xiaoli Wang,1,2,* Yijun Luo,1,2,* Minghuan Li,2 Hongjiang Yan,2 Mingping Sun,2 Tingyong Fan2 1School of Medicine and Life Sciences, Jinan University-Shandong Academy of Medical Sciences, Jinan, Shandong, People’s Republic of China; 2Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan, Shandong, People’s Republic of China *These authors contributed equally to this work Background: Postoperative radiotherapy has shown positive efficacy in lowering the recurrence rate and improving the survival rate for patients with esophageal squamous cell carcinoma (ESCC. However, controversies still exist about the postoperative prophylactic radiation target volume. This study was designed to analyze the patterns of recurrence and to provide a reference for determination of the postoperative radiotherapy target volume for patients with midthoracic ESCC.Patients and methods: A total of 338 patients with recurrent or metastatic midthoracic ESCC after radical surgery were retrospectively examined. The patterns of recurrence including locoregional and distant metastasis were analyzed for these patients.Results: The rates of lymph node (LN metastasis were 28.4% supraclavicular, 77.2% upper mediastinal, 32.0% middle mediastinal, 50.0% lower mediastinal, and 19.5% abdominal LNs. In subgroup analyses, the rate of abdominal LN metastasis was significantly higher in patients with histological node-positive than that in patients with histological node-negative (P=0.033. Further analysis in patients with histological node-positive demonstrated that patients with three or more positive nodes are more prone to abdominal LN metastasis, compared with patients with one or two positive nodes (χ2=4.367, P=0.037. The length of tumor and histological differentiation were also the high-risk factors for abdominal LN metastasis.Conclusion: For midthoracic ESCC with histological node-negative, or one or two positive nodes, the supraclavicular and

  14. Sparing Healthy Tissue and Increasing Tumor Dose Using Bayesian Modeling of Geometric Uncertainties for Planning Target Volume Personalization

    International Nuclear Information System (INIS)

    Objective: To develop a mathematical tool that can update a patient's planning target volume (PTV) partway through a course of radiation therapy to more precisely target the tumor for the remainder of treatment and reduce dose to surrounding healthy tissue. Methods and Materials: Daily on-board imaging was used to collect large datasets of displacements for patients undergoing external beam radiation therapy for solid tumors. Bayesian statistical modeling of these geometric uncertainties was used to optimally trade off between displacement data collected from previously treated patients and the progressively accumulating data from a patient currently partway through treatment, to optimally predict future displacements for that patient. These predictions were used to update the PTV position and margin width for the remainder of treatment, such that the clinical target volume (CTV) was more precisely targeted. Results: Software simulation of dose to CTV and normal tissue for 2 real prostate displacement datasets consisting of 146 and 290 patients treated with a minimum of 30 fractions each showed that re-evaluating the PTV position and margin width after 8 treatment fractions reduced healthy tissue dose by 19% and 17%, respectively, while maintaining CTV dose. Conclusion: Incorporating patient-specific displacement patterns from early in a course of treatment allows PTV adaptation for the remainder of treatment. This substantially reduces the dose to healthy tissues and thus can reduce radiation therapy–induced toxicities, improving patient outcomes

  15. Sparing Healthy Tissue and Increasing Tumor Dose Using Bayesian Modeling of Geometric Uncertainties for Planning Target Volume Personalization

    Energy Technology Data Exchange (ETDEWEB)

    Herschtal, Alan, E-mail: Alan.Herschtal@petermac.org [Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne (Australia); Faculty of Health, Arts and Design, Swinburne University of Technology, Melbourne (Australia); Te Marvelde, Luc [Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne (Australia); Mengersen, Kerrie [School of Mathematical Sciences, Science and Engineering Faculty, Queensland University of Technology, Brisbane (Australia); Foroudi, Farshad [Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne (Australia); The Sir Peter MacCallum Department of Oncology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne (Australia); Eade, Thomas [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St. Leonards, Sydney (Australia); Northern Clinical School, University of Sydney (Australia); Pham, Daniel [Department of Radiation Therapy, Peter MacCallum Cancer Centre, Melbourne (Australia); Caine, Hannah [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St. Leonards, Sydney (Australia); Kron, Tomas [The Sir Peter MacCallum Department of Oncology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne (Australia); Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne (Australia)

    2015-06-01

    Objective: To develop a mathematical tool that can update a patient's planning target volume (PTV) partway through a course of radiation therapy to more precisely target the tumor for the remainder of treatment and reduce dose to surrounding healthy tissue. Methods and Materials: Daily on-board imaging was used to collect large datasets of displacements for patients undergoing external beam radiation therapy for solid tumors. Bayesian statistical modeling of these geometric uncertainties was used to optimally trade off between displacement data collected from previously treated patients and the progressively accumulating data from a patient currently partway through treatment, to optimally predict future displacements for that patient. These predictions were used to update the PTV position and margin width for the remainder of treatment, such that the clinical target volume (CTV) was more precisely targeted. Results: Software simulation of dose to CTV and normal tissue for 2 real prostate displacement datasets consisting of 146 and 290 patients treated with a minimum of 30 fractions each showed that re-evaluating the PTV position and margin width after 8 treatment fractions reduced healthy tissue dose by 19% and 17%, respectively, while maintaining CTV dose. Conclusion: Incorporating patient-specific displacement patterns from early in a course of treatment allows PTV adaptation for the remainder of treatment. This substantially reduces the dose to healthy tissues and thus can reduce radiation therapy–induced toxicities, improving patient outcomes.

  16. Impact of 18F-FDG PET/CT on target volume delineation in recurrent or residual gynaecologic carcinoma

    International Nuclear Information System (INIS)

    To evaluate the impact of 18F-FDG PET/CT on target volume delineation in gynaecological cancer. F-FDG PET/CT based RT treatment planning was performed in 10 patients with locally recurrent (n = 5) or post-surgical residual gynaecological cancer (n = 5). The gross tumor volume (GTV) was defined by 4 experienced radiation oncologists first using contrast enhanced CT (GTVCT) and secondly using the fused 18F-FDG PET/CT datasets (GTVPET/CT). In addition, the GTV was delineated using the signal-to-background (SBR) ratio-based adaptive thresholding technique (GTVSBR). Overlap analysis were conducted to assess geographic mismatches between the GTVs delineated using the different techniques. Inter- and intra-observer variability were also assessed. The mean GTVCT (43.65 cm3) was larger than the mean GTVPET/CT (33.06 cm3), p = 0.02. In 6 patients, GTVPET/CT added substantial tumor extension outside the GTVCT even though 90.4% of the GTVPET/CT was included in the GTVCT and 30.2% of the GTVCT was found outside the GTVPET/CT. The inter- and intra-observer variability was not significantly reduced with the inclusion of 18F-FDG PET imaging (p = 0.23 and p = 0.18, respectively). The GTVSBR was smaller than GTVCT p ≤ 0.005 and GTVPET/CT p ≤ 0.005. The use of 18F-FDG PET/CT images for target volume delineation of recurrent or post-surgical residual gynaecological cancer alters the GTV in the majority of patients compared to standard CT-definition. The use of SBR-based auto-delineation showed significantly smaller GTVs. The use of PET/CT based target volume delineation may improve the accuracy of RT treatment planning in gynaecologic cancer

  17. Determination of Internal Target Volume From a Single Positron Emission Tomography/Computed Tomography Scan in Lung Cancer

    International Nuclear Information System (INIS)

    Purpose: The use of four-dimensional computed tomography (4D-CT) to determine the tumor internal target volume (ITV) is usually characterized by high patient radiation exposure. The objective of this study was to propose and evaluate an approach that relies on a single static positron emission tomography (PET)/CT scan to determine the ITV, thereby eliminating the need for 4D-CT and thus reduce patient radiation dose. Methods and Materials: The proposed approach is based on the concept that the observed PET image is the result of a joint convolution of an ideal PET image (free from motion and partial volume effect) with a motion-blurring kernel (MBK) and partial volume effect. In this regard, the MBK and tumor ITV are then estimated from the deconvolution of this joint model. To test this technique, phantom and patient studies were performed using different sphere/tumor sizes and motion trajectories. In all studies, a 4D-CT and a PET/CT image of the sphere/tumor were acquired. The ITV from the proposed technique was then compared to the maximum intensity projection (MIP) volume of the 4D-CT images. A Dice coefficient of the two volumes was calculated to represent the similarity between the two ITVs. Results: The average ITVs of the proposed technique were 97.2% ± 0.3% and 81.0% ± 16.7% similar to the MIP volume in the phantom and patient studies, respectively. The average dice coefficients were 0.87 ± 0.05 and 0.73 ± 0.16, respectively, for the two studies. Conclusion: Using the proposed approach, a single static PET/CT scan has the potential to replace a 4D-CT to determine the tumor ITV. This approach has the added advantage of reducing patient radiation exposure and determining the tumor MBK compared to 4D-CT/MIP-CT.

  18. A Beam-Specific Planning Target Volume (PTV) Design for Proton Therapy to Account for Setup and Range Uncertainties

    International Nuclear Information System (INIS)

    Purpose: To report a method for explicitly designing a planning target volume (PTV) for treatment planning and evaluation in heterogeneous media for passively scattered proton therapy and scanning beam proton therapy using single-field optimization (SFO). Methods and Materials: A beam-specific PTV (bsPTV) for proton beams was derived by ray-tracing and shifting ray lines to account for tissue misalignment in the presence of setup error or organ motion. Range uncertainties resulting from inaccuracies in computed tomography–based range estimation were calculated for proximal and distal surfaces of the target in the beam direction. The bsPTV was then constructed based on local heterogeneity. The bsPTV thus can be used directly as a planning target as if it were in photon therapy. To test the robustness of the bsPTV, we generated a single-field proton plan in a virtual phantom. Intentional setup and range errors were introduced. Dose coverage to the clinical target volume (CTV) under various simulation conditions was compared between plans designed based on the bsPTV and a conventional PTV. Results: The simulated treatment using the bsPTV design performed significantly better than the plan using the conventional PTV in maintaining dose coverage to the CTV. With conventional PTV plans, the minimum coverage to the CTV dropped from 99% to 67% in the presence of setup error, internal motion, and range uncertainty. However, plans using the bsPTV showed minimal drop of target coverage from 99% to 94%. Conclusions: The conventional geometry-based PTV concept used in photon therapy does not work well for proton therapy. We investigated and validated a beam-specific PTV method for designing and evaluating proton plans.

  19. Target Volume Delineation in Oropharyngeal Cancer: Impact of PET, MRI, and Physical Examination

    International Nuclear Information System (INIS)

    Introduction: Sole utilization of computed tomography (CT) scans in gross tumor volume (GTV) delineation for head-and-neck cancers is subject to inaccuracies. This study aims to evaluate contributions of magnetic resonance imaging (MRI), positron emission tomography (PET), and physical examination (PE) to GTV delineation in oropharyngeal cancer (OPC). Methods: Forty-one patients with OPC were studied. All underwent contrast-enhanced CT simulation scans (CECTs) that were registered with pretreatment PETs and MRIs. For each patient, three sets of primary and nodal GTV were contoured. First, reference GTVs (GTVref) were contoured by the treating radiation oncologist (RO) using CT, MRI, PET, and PE findings. Additional GTVs were created using fused CT/PET scans (GTVctpet) and CT/MRI scans (GTVctmr) by two other ROs blinded to GTVref. To compare GTVs, concordance indices (CI) were calculated by dividing the respective overlap volumes by overall volumes. To evaluate the contribution of PE, composite GTVs derived from CT, MRI, and PET (GTVctpetmr) were compared with GTVref. Results: For primary tumors, GTVref was significantly larger than GTVctpet and GTVctmr (p 0.75), indicating that although the modalities were complementary, the added benefit was small in the context of CECTs. In addition, PE did not aid greatly in nodal GTV delineation. Conclusion: PET and MRI are complementary and combined use is ideal. However, the low CI (ctpetmr vs. ref) particularly for primary tumors underscores the limitations of defining GTVs using imaging alone. PE is invaluable and must be incorporated.

  20. A clip-based protocol for breast boost radiotherapy provides clear target visualisation and demonstrates significant volume reduction over time

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Lorraine [Department of Radiation Oncology, Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales (Australia); Cox, Jennifer [Department of Radiation Oncology, Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales (Australia); Faculty of Health Sciences, University of Sydney, Sydney, New South Wales (Australia); Morgia, Marita [Department of Radiation Oncology, Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales (Australia); Atyeo, John [Faculty of Health Sciences, University of Sydney, Sydney, New South Wales (Australia); Lamoury, Gillian [Department of Radiation Oncology, Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales (Australia)

    2015-09-15

    The clinical target volume (CTV) for early stage breast cancer is difficult to clearly identify on planning computed tomography (CT) scans. Surgical clips inserted around the tumour bed should help to identify the CTV, particularly if the seroma has been reabsorbed, and enable tracking of CTV changes over time. A surgical clip-based CTV delineation protocol was introduced. CTV visibility and its post-operative shrinkage pattern were assessed. The subjects were 27 early stage breast cancer patients receiving post-operative radiotherapy alone and 15 receiving post-operative chemotherapy followed by radiotherapy. The radiotherapy alone (RT/alone) group received a CT scan at median 25 days post-operatively (CT1rt) and another at 40 Gy, median 68 days (CT2rt). The chemotherapy/RT group (chemo/RT) received a CT scan at median 18 days post-operatively (CT1ch), a planning CT scan at median 126 days (CT2ch), and another at 40 Gy (CT3ch). There was no significant difference (P = 0.08) between the initial mean CTV for each cohort. The RT/alone cohort showed significant CTV volume reduction of 38.4% (P = 0.01) at 40 Gy. The Chemo/RT cohort had significantly reduced volumes between CT1ch: median 54 cm{sup 3} (4–118) and CT2ch: median 16 cm{sup 3}, (2–99), (P = 0.01), but no significant volume reduction thereafter. Surgical clips enable localisation of the post-surgical seroma for radiotherapy targeting. Most seroma shrinkage occurs early, enabling CT treatment planning to take place at 7 weeks, which is within the 9 weeks recommended to limit disease recurrence.

  1. A clip-based protocol for breast boost radiotherapy provides clear target visualisation and demonstrates significant volume reduction over time

    International Nuclear Information System (INIS)

    The clinical target volume (CTV) for early stage breast cancer is difficult to clearly identify on planning computed tomography (CT) scans. Surgical clips inserted around the tumour bed should help to identify the CTV, particularly if the seroma has been reabsorbed, and enable tracking of CTV changes over time. A surgical clip-based CTV delineation protocol was introduced. CTV visibility and its post-operative shrinkage pattern were assessed. The subjects were 27 early stage breast cancer patients receiving post-operative radiotherapy alone and 15 receiving post-operative chemotherapy followed by radiotherapy. The radiotherapy alone (RT/alone) group received a CT scan at median 25 days post-operatively (CT1rt) and another at 40 Gy, median 68 days (CT2rt). The chemotherapy/RT group (chemo/RT) received a CT scan at median 18 days post-operatively (CT1ch), a planning CT scan at median 126 days (CT2ch), and another at 40 Gy (CT3ch). There was no significant difference (P = 0.08) between the initial mean CTV for each cohort. The RT/alone cohort showed significant CTV volume reduction of 38.4% (P = 0.01) at 40 Gy. The Chemo/RT cohort had significantly reduced volumes between CT1ch: median 54 cm3 (4–118) and CT2ch: median 16 cm3, (2–99), (P = 0.01), but no significant volume reduction thereafter. Surgical clips enable localisation of the post-surgical seroma for radiotherapy targeting. Most seroma shrinkage occurs early, enabling CT treatment planning to take place at 7 weeks, which is within the 9 weeks recommended to limit disease recurrence

  2. Defining Radiotherapy Target Volumes Using 18F-Fluoro-Deoxy-Glucose Positron Emission Tomography/Computed Tomography: Still a Pandora's Box?

    International Nuclear Information System (INIS)

    Purpose: We discuss the effect of 18F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) data on target volume definition for radiotherapy planning. We compared the effect of various thresholding methods on the PET-based target volume vs. the standard CT-based tumor volume. Methods and Materials: Different thresholding methods were reviewed and compared to our PET-based gross tumor volume data obtained from a cohort of 31 non-small-cell lung carcinoma patients who had undergone preoperative PET/CT scans for staging. The feasibility and limitations of FDG-based PET/CT data on target volume delineation in radiotherapy planning have been demonstrated with frequently used approaches for target outlining such as the qualitative visual method and the fixed 15% or 40% of the maximal iso-uptake value threshold methods. Results: The relationship between PET-based and CT-based volumes generally suffers from poor correlation between the two image data sets, expressed in terms of a large statistical variation in gross tumor volume ratios, irrespective of the threshold method used. However, we found that the maximal signal/background ratios in non-small-cell lung carcinoma patients correlated well with the pathologic results, with an average ratio for adenocarcinoma, large cell carcinoma, and squamous cell carcinoma of 10.5 ± 3.5, 12.6 ± 2.8, and 14.1 ± 5.9, respectively. Conclusion: The fluctuations in tumor volume using different quantitative PET thresholding approaches did not depend on the thresholding method used. They originated from the nature of functional imaging in general and PET imaging in particular. Functional imaging will eventually be used for biologically tailored target radiotherapy volume definition not as a replacement of CT- or magnetic resonance imaging-based anatomic gross tumor volumes but with the methods complementing each other in a complex mosaic of distinct biologic target volumes.

  3. Internal target volume determined with expansion margins beyond composite gross tumor volume in three-dimensional conformal radiotherapy for lung cancer

    International Nuclear Information System (INIS)

    Purpose: Gross tumor volume (GTV) of lung cancer defined by fast helical CT scan represents an image of moving tumor captured at a point in active respiratory movement. However, the method for defining internal margins beyond GTV to account for its expected physiologic movement and all variations in size and shape during the administration of radiation has not been established. The goal of this study was to determine the internal margins with expansion margins beyond individual GTVs defined with (1) fast scan at shallow free breathing (2) breath-hold scans at the end of tidal volume inspiration and expiration, and (3) 4-s slow scan to approximate the composite GTV of all scans. Methods and materials: A series of sequential CT scans were acquired with (1) a fast helical scan at shallow free breathing and (2) breath-hold scans at the end of tidal volume expiration and inspiration for the first 6 patients, and (3) a 4-s slow scan at quiet free breathing, which was added for the latter 7 patients. We fused breath-hold scans and the 4-s slow scan to the fast scan at shallow free breathing to generate the composite GTV. Margins necessary to encompass the composite GTV beyond individual GTVs defined by either fast scan at quiet free breathing, breath-hold scans, or the 4-s slow scan at quiet free breathing were defined as expansion or internal margins and termed the internal target volumes. The centroid of the tumor volume was also used as another reference for tumor movement. Results: Thirteen patients with 14 tumors were enrolled into the study. Substantial tumor movement was noted by either the extent of internal margins beyond each GTV or the movement of the centroid. Internal margins varied significantly according to the method of CT scanning for determination of GTV. Even for tumors in the same lobe of the lung, a wide range of internal margins and significant variation in the centroid movement in all directions (x, y, and z) were observed. The GTV of a single fast

  4. Evaluation of dose-volume histogram parameters (V20 and mean dose) in lung cancer adaptive radiotherapy with design of composite lung volumes (ITV; Evaluacion de parametros del histograma dosis-volumen (V20 y dosis media) en radioterapia adaptada de cancer de pulmon con diseno de volumenes pulmonares compuestos (Internal Target Volume, ITV)

    Energy Technology Data Exchange (ETDEWEB)

    Monroy Anton, J. L.; Solar Tortosa, M.; Lopez Munoz, M.; Navarro Bergada, A.; Estornell gualde, M. A.; Melchor Iniguez, M.

    2013-07-01

    Physiological respiratory motion is a challenge in external radiotherapy for lung tumors. In adaptive radiotherapy, changing position of the target volume should be reflected in the simulation procedure and taken into account in the design of volumes for CTV/PTV proper coverage. This may be achieved through the design of an Internal Target Volume (ITV) as indicated in ICRU-62. However, the Dose-Volume Histogram (DVH) evaluation of the doses received by the healthy lung may vary in the case of designing a single lung volume, compared to the composite lung volume obtained with the fusion of normal breathing, inspiration and expiration (ITV{sub l}ung). (Author)

  5. Development of whole-building energy design targets for commercial buildings: Phase 1, Planning: Volume 2, Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Crawley, D.B.; Briggs, R.S.; Jones, J.W.; Seaton, W.W.; Kaufman, J.E.; Deringer, J.J.; Kennett, E.W.

    1987-08-01

    This is the second volume of the Phase 1 report and discusses the 10 tasks performed in Phase 1. The objective of this research is to develop a methodology for setting energy design targets to provide voluntary guidelines for the buildings industry. The whole-building energy targets project is being conducted at the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) to encourage the construction of energy-efficient buildings by informing designers and owners about cost-effective goals for energy use in new commercial buildings. The outcome of this research will be a flexible methodology for setting such targets. The tasks are listed and discussed in this report as follows: Task 1 - Develop Detailed Project Goals and Objectives; Task 2 - Establish Buildings-Industry Liaison; Task 3 - Develop Approaches to the Energy Targets Model, Building Operations, and Climate; Task 4 - Develop an Approach for Treating Economic Considerations; Task 5 - Develop an Approach for Treating Energy Sources; Task 6 - Collect Energy-Use Data; Task 7 - Survey Energy Expert Opinion; Task 8 - Evaluation Procedure Specification and Integration; Task 9 - Phase 1 Report Development; and Task 10 - Phase 1 Review Planning.

  6. Physics of laser fusion. Volume II. Diagnostics of experiments on laser fusion targets at LLNL

    International Nuclear Information System (INIS)

    These notes present the experimental basis and status for laser fusion as developed at LLNL. There are two other volumes in this series: Vol. I, by C.E. Max, presents the theoretical laser-plasma interaction physics; Vol. III, by J.F. Holzrichter et al., presents the theory and design of high-power pulsed lasers. A fourth volume will present the theoretical implosion physics. The notes consist of six sections. The first, an introductory section, provides some of the history of inertial fusion and a simple explanation of the concepts involved. The second section presents an extensive discussion of diagnostic instrumentation used in the LLNL Laser Fusion Program. The third section is a presentation of laser facilities and capabilities at LLNL. The purpose here is to define capability, not to derive how it was obtained. The fourth and fifth sections present the experimental data on laser-plasma interaction and implosion physics. The last chapter is a short projection of the future

  7. Chemoradiation for Ductal Pancreatic Carcinoma: Principles of Combining Chemotherapy with Radiation, Definition of Target Volume and Radiation Dose

    Directory of Open Access Journals (Sweden)

    Heinemann V

    2005-05-01

    Full Text Available Review of the role of chemoradiotherapy in the treatment of locally advanced pancreatic cancer with a specific focus on the technical feasibility and the integration of chemoradiotherapy into multimodal treatment concepts. Combined chemoradiotherapy of pancreatic cancer is a safe treatment with an acceptable profile of side effects when applied with modern planning and radiation techniques as well as considering tissue tolerance. Conventionally fractionated radiation regimens with total doses of 45-50 Gy and small-volume boost radiation with 5.4 Gy have found the greatest acceptance. Locoregional lymphatic drainage should be included in the planning of target volumes because the risk of tumor involvement and local or loco-regional recurrence is high. Up to now, 5-fluorouracil has been considered the "standard" agent for concurrent chemoradiotherapy. The role of gemcitabine given concurrently with radiation has not yet been defined, since high local efficacy may also be accompanied by enhanced toxicities. In addition, no dose or administration form has been determined to be "standard" up to now. The focus of presently ongoing research is to define an effective and feasible regimen of concurrent chemoradiotherapy. While preliminary results indicate promising results using gemcitabine-based chemoradiotherapy, reliable data derived from mature phase III trials are greatly needed. Intensity-modulated radiotherapy has been developed to improve target-specific radiation and to reduce organ toxicity. Its clinical relevance still needs to be defined.

  8. Technical review of target volume delineation on the posterior fossa tumor: an optimal head and neck position

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sang Min; Lee, Sang Wook; Ahn, Seung Do; Kim, Jong Hoon; Yi, Byong Yong; Ra, Young Shin; Ghim, Thad; Choi, Eun Kyung [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of)

    2003-03-01

    To explore a 3D conformal radiotherapy technique for a posterior fossa boost, and the potential advantages of a prone position for such radiotherapy, A CT simulator and 3D conformal radiotherapy planning system was used for the posterior fossa boost treatment of a 13-year-old medulloblastoma patient. He was placed in the prone position and immobilized with an aquaplast mask and immobilization mold. CT scans were obtained of the brain from the top of the skull to the lower neck, with IV contrast enhancement. The target volume and normal structures were delineated on each slice, with treatment planning performed using non-coplanar conformal beams. The CT scans, and treatment in the prone position, were performed successfully. In the prone position, the definition of the target volume was made easier due to the well enhanced tentorium. In addition, the posterior fossa was located anteriorly, and with the greater choice of beam arrangements, more accurate treatment planning was possible as the primary beams were not obstructed by the treatment table. A posterior fossa boost, in the prone position, is feasible in cooperating patients, but further evaluation is needed to define the optimal and most comfortable treatment positions.

  9. Impact of 18F-FDG PET/CT on target volume delineation in recurrent or residual gynaecologic carcinoma

    Directory of Open Access Journals (Sweden)

    Vees Hansjörg

    2012-10-01

    Full Text Available Abstract Background To evaluate the impact of 18F-FDG PET/CT on target volume delineation in gynaecological cancer. Methods F-FDG PET/CT based RT treatment planning was performed in 10 patients with locally recurrent (n = 5 or post-surgical residual gynaecological cancer (n = 5. The gross tumor volume (GTV was defined by 4 experienced radiation oncologists first using contrast enhanced CT (GTVCT and secondly using the fused 18F-FDG PET/CT datasets (GTVPET/CT. In addition, the GTV was delineated using the signal-to-background (SBR ratio-based adaptive thresholding technique (GTVSBR. Overlap analysis were conducted to assess geographic mismatches between the GTVs delineated using the different techniques. Inter- and intra-observer variability were also assessed. Results The mean GTVCT (43.65 cm3 was larger than the mean GTVPET/CT (33.06 cm3, p = 0.02. In 6 patients, GTVPET/CT added substantial tumor extension outside the GTVCT even though 90.4% of the GTVPET/CT was included in the GTVCT and 30.2% of the GTVCT was found outside the GTVPET/CT. The inter- and intra-observer variability was not significantly reduced with the inclusion of 18F-FDG PET imaging (p = 0.23 and p = 0.18, respectively. The GTVSBR was smaller than GTVCT p ≤ 0.005 and GTVPET/CT p ≤ 0.005. Conclusions The use of 18F-FDG PET/CT images for target volume delineation of recurrent or post-surgical residual gynaecological cancer alters the GTV in the majority of patients compared to standard CT-definition. The use of SBR-based auto-delineation showed significantly smaller GTVs. The use of PET/CT based target volume delineation may improve the accuracy of RT treatment planning in gynaecologic cancer.

  10. World-volume and target-space anomalies in the D=10 super-fivebrane sigma model

    Energy Technology Data Exchange (ETDEWEB)

    Lechner, K. [Padua Univ. (Italy). Dipt. di Fisica; Tonin, M. [Padua Univ. (Italy). Dipt. di Fisica

    1996-09-16

    The fields of the conjectured ``heterotic`` super-fivebrane sigma model in ten dimensions are made out of a well-known gravitational sector, the X and the {theta}, and of a still unknown heterotic sector which should be coupled to the Yang-Mills fields. We compute the one-loop d=6 world-volume and D=10 target-space Lorentz anomalies which arise from the gravitational sector of the heterotic super-fivebrane sigma model, using a method which we developed previously for the Green-Schwarz heterotic superstring. These anomalies turn out to carry an overall coefficient which is half of that required by the string-fivebrane duality conjecture. As a consequence, the world-volume anomaly vanishes if the heterotic fields consist of 16 (rather than 32) complex Weyl fermions on the world-volume. This implies that the string-fivebrane duality conjecture can not be based on a ``heterotic`` super-fivebrane sigma model with only fermions in the heterotic sector. Possible implications of this result are discussed. (orig.).

  11. 鼻咽癌临床靶区定义%Definition of clinical target volume (CTV) for nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    林少俊; 潘建基; 郭巧娟

    2011-01-01

    Radiation therapy is the mainstay treatment modality for nasopharyngeal carcinoma (NPC), and the outcome is well associated to radiation dose. As a precise radiation technology, intensity-modulated radiotherapy (IMRT) offers the possibility of improving survival and simultaneously protect the surrounding normal tissue. The improvement of local control by IMRT has been well confirmed by a number of studies form domestic and abroad. However, the selection and definition of clinical target volume (CTV) for nasopharyngeal carcinoma has not yet reached a consensus. This article aimed to discovery the direction and mode for future research of reducing the treatment volume by reviewing the domestic and international development of CTV.%鼻咽癌为放射剂量相关性恶性肿瘤,放射治疗是鼻咽癌的首选治疗方法.调强放射治疗作为精确的放疗技术为提高剂量、保护周围正常组织提供了可能,国内外多家放疗中心的研究结果己证实调强放疗可提高鼻咽癌局部控制率.然而,当前对鼻咽癌的亚临床靶区(clinical target volume,CTV)的界定尚未达成共识,本文通过回顾国内外鼻咽癌CTV定义的发展过程,探讨未来缩小鼻咽癌靶区定义的发展方向和模式.

  12. Effect of interfractional shoulder motion on low neck nodal targets for patients treated using volume modulated arc therapy (VMAT

    Directory of Open Access Journals (Sweden)

    Kevin Casey

    2014-03-01

    Full Text Available Purpose: To quantify the dosimetric impact of interfractional shoulder motion on targets in the low neck for head and neck patients treated with volume modulated arc therapy (VMAT.Methods: Three patients with head and neck cancer were selected. All three required treatment to nodal regions in the low neck in addition to the primary tumor site. The patients were immobilized during simulation and treatment with a custom thermoplastic mask covering the head and shoulders. One VMAT plan was created for each patient utilizing two full 360° arcs and a second plan was created consisting of two superior VMAT arcs matched to an inferior static AP supraclavicular field. A CT-on-rails alignment verification was performed weekly during each patient’s treatment course. The weekly CT images were registered to the simulation CT and the target contours were deformed and applied to the weekly CT. The two VMAT plans were copied to the weekly CT datasets and recalculated to obtain the dose to the deformed low neck contours.Results: The average observed shoulder position shift in any single dimension relative to simulation was 2.5 mm. The maximum shoulder shift observed in a single dimension was 25.7 mm. Low neck target mean doses, normalized to simulation and averaged across all weekly recalculations were 0.996, 0.991, and 1.033 (Full VMAT plan and 0.986, 0.995, and 0.990 (Half-Beam VMAT plan for the three patients, respectively. The maximum observed deviation in target mean dose for any individual weekly recalculation was 6.5%, occurring with the Full VMAT plan for Patient 3.Conclusion: Interfractional variation in dose to low neck nodal regions was quantified for three head and neck patients treated with VMAT. Mean dose was 3.3% higher than planned for one patient using a Full VMAT plan. A Half-Beam technique is likely a safer choice when treating the supraclavicular region with VMAT.-------------------------------------------Cite this article as: Casey K

  13. The ADVANCE project: Formal evaluation of the targeted deployment. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    ADVANCE [Advanced Driver and Vehicle Advisory Navigation ConcEpt] was a public/private partnership conceived and developed by four founding parties. The founding parties include the Federal Highway Administration (FHWA), the Illinois Department of Transportation (IDOT), the University of Illinois at Chicago and Northwestern University operating together under the auspices of the Illinois Universities Transportation Research Consortium (IUTRC), and Motorola, Inc. The major responsibilities of each party are fully described in the Project agreement. Subsequently, these four were joined on the Steering Committee by the American Automobile Association (AAA). This unique blending of public sector, private sector and university interests, augmented by more than two dozen other private sector participants, provided a strong set of resources for ADVANCE. The ADVANCE test area covered over 300 square miles including portions of the City of Chicago and 40 northwest suburban communities. The Project encompasses the high growth areas adjacent to O`Hare International Airport, the Schaumbura/Hoffman Estates office and retail complexes, and the Lake-Cook Road development corridor. It also includes major sports and entertainment complexes such as the Arlington International Racecourse and the Rosemont Horizon. The population in the area is more than 750,000. This volume provides a summary of the insights and achievements made as a result of this field test, and selected appendices containing more detailed information.

  14. Accuracy of relocation, evaluation of geometric uncertainties and clinical target volume (CTV) to planning target volume (PTV) margin in fractionated stereotactic radiotherapy for intracranial tumors using relocatable Gill-Thomas-Cosman (GTC) frame.

    Science.gov (United States)

    Das, Saikat; Isiah, Rajesh; Rajesh, B; Ravindran, B Paul; Singh, Rabi Raja; Backianathan, Selvamani; Subhashini, J

    2011-01-01

    The present study is aimed at determination of accuracy of relocation of Gill-Thomas-Cosman frame during fractionated stereotactic radiotherapy. The study aims to quantitatively determine the magnitudes of error in anteroposterior, mediolateral and craniocaudal directions, and determine the margin between clinical target volume to planning target volume based on systematic and random errors. Daily relocation error was measured using depth helmet and measuring probe. Based on the measurements, translational displacements in anteroposterior (z), mediolateral (x), and craniocaudal (y) directions were calculated. Based on the displacements in x, y and z directions, systematic and random error were calculated and three-dimensional radial displacement vector was determined. Systematic and random errors were used to derive CTV to PTV margin. The errors were within ± 2 mm in 99.2% cases in anteroposterior direction (AP), in 99.6% cases in mediolateral direction (ML), and in 97.6% cases in craniocaudal direction (CC). In AP, ML and CC directions, systematic errors were 0.56, 0.38, 0.42 mm and random errors were 1.86, 1.36 and 0.73 mm, respectively. Mean radial displacement was 1.03 mm ± 0.34. CTV to PTV margins calculated by ICRU formula were 1.86, 1.45 and 0.93 mm; by Stroom's formula they were 2.42, 1.74 and 1.35 mm; by van Herk's formula they were 2.7, 1.93 and 1.56 mm (AP, ML and CC directions). Depth helmet with measuring probe provides a clinically viable way for assessing the relocation accuracy of GTC frame. The errors were within ± 2 mm in all directions. Systematic and random errors were more along the anteroposterior axes. According to the ICRU formula, a margin of 2 mm around the tumor seems to be adequate. PMID:21587166

  15. Intensity modulated radiotherapy for high risk prostate cancer based on sentinel node SPECT imaging for target volume definition

    Directory of Open Access Journals (Sweden)

    Anastasiadis Aristotelis

    2005-07-01

    Full Text Available Abstract Background The RTOG 94-13 trial has provided evidence that patients with high risk prostate cancer benefit from an additional radiotherapy to the pelvic nodes combined with concomitant hormonal ablation. Since lymphatic drainage of the prostate is highly variable, the optimal target volume definition for the pelvic lymph nodes is problematic. To overcome this limitation, we tested the feasibility of an intensity modulated radiation therapy (IMRT protocol, taking under consideration the individual pelvic sentinel node drainage pattern by SPECT functional imaging. Methods Patients with high risk prostate cancer were included. Sentinel nodes (SN were localised 1.5–3 hours after injection of 250 MBq 99mTc-Nanocoll using a double-headed gamma camera with an integrated X-Ray device. All sentinel node localisations were included into the pelvic clinical target volume (CTV. Dose prescriptions were 50.4 Gy (5 × 1.8 Gy / week to the pelvis and 70.0 Gy (5 × 2.0 Gy / week to the prostate including the base of seminal vesicles or whole seminal vesicles. Patients were treated with IMRT. Furthermore a theoretical comparison between IMRT and a three-dimensional conformal technique was performed. Results Since 08/2003 6 patients were treated with this protocol. All patients had detectable sentinel lymph nodes (total 29. 4 of 6 patients showed sentinel node localisations (total 10, that would not have been treated adequately with CT-based planning ('geographical miss' only. The most common localisation for a probable geographical miss was the perirectal area. The comparison between dose-volume-histograms of IMRT- and conventional CT-planning demonstrated clear superiority of IMRT when all sentinel lymph nodes were included. IMRT allowed a significantly better sparing of normal tissue and reduced volumes of small bowel, large bowel and rectum irradiated with critical doses. No gastrointestinal or genitourinary acute toxicity Grade 3 or 4 (RTOG

  16. Intensity modulated radiotherapy for high risk prostate cancer based on sentinel node SPECT imaging for target volume definition

    International Nuclear Information System (INIS)

    The RTOG 94-13 trial has provided evidence that patients with high risk prostate cancer benefit from an additional radiotherapy to the pelvic nodes combined with concomitant hormonal ablation. Since lymphatic drainage of the prostate is highly variable, the optimal target volume definition for the pelvic lymph nodes is problematic. To overcome this limitation, we tested the feasibility of an intensity modulated radiation therapy (IMRT) protocol, taking under consideration the individual pelvic sentinel node drainage pattern by SPECT functional imaging. Patients with high risk prostate cancer were included. Sentinel nodes (SN) were localised 1.5–3 hours after injection of 250 MBq 99mTc-Nanocoll using a double-headed gamma camera with an integrated X-Ray device. All sentinel node localisations were included into the pelvic clinical target volume (CTV). Dose prescriptions were 50.4 Gy (5 × 1.8 Gy / week) to the pelvis and 70.0 Gy (5 × 2.0 Gy / week) to the prostate including the base of seminal vesicles or whole seminal vesicles. Patients were treated with IMRT. Furthermore a theoretical comparison between IMRT and a three-dimensional conformal technique was performed. Since 08/2003 6 patients were treated with this protocol. All patients had detectable sentinel lymph nodes (total 29). 4 of 6 patients showed sentinel node localisations (total 10), that would not have been treated adequately with CT-based planning ('geographical miss') only. The most common localisation for a probable geographical miss was the perirectal area. The comparison between dose-volume-histograms of IMRT- and conventional CT-planning demonstrated clear superiority of IMRT when all sentinel lymph nodes were included. IMRT allowed a significantly better sparing of normal tissue and reduced volumes of small bowel, large bowel and rectum irradiated with critical doses. No gastrointestinal or genitourinary acute toxicity Grade 3 or 4 (RTOG) occurred. IMRT based on sentinel lymph node

  17. Are we ready for positron emission tomography/computed tomography-based target volume definition in lymphoma radiation therapy?

    Science.gov (United States)

    Yeoh, Kheng-Wei; Mikhaeel, N George

    2013-01-01

    Fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has become indispensable for the clinical management of lymphomas. With consistent evidence that it is more accurate than anatomic imaging in the staging and response assessment of many lymphoma subtypes, its utility continues to increase. There have therefore been efforts to incorporate PET/CT data into radiation therapy decision making and in the planning process. Further, there have also been studies investigating target volume definition for radiation therapy using PET/CT data. This article will critically review the literature and ongoing studies on the above topics, examining the value and methods of adding PET/CT data to the radiation therapy treatment algorithm. We will also discuss the various challenges and the areas where more evidence is required.

  18. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-08-01

    Full Text Available Wei Wang, Jianbin Li, Yingjie Zhang, Qian Shao, Min Xu, Tingyong Fan, Jinzhi Wang Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Shandong, People’s Republic of China Background and purpose: To investigate the definition of planning target volumes (PTVs based on four-dimensional computed tomography (4DCT compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. Materials and methods: Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathing. The motions of primary tumors located in the proximal (group A, middle (group B, and distal (group C thoracic esophagus were obtained from the 4DCT scans. PTV3D was defined on 3DCT using the tumor motion measured based on 4DCT, PTV conventional (PTVconv was defined on 3DCT by adding a 1.0 cm margin to the clinical target volume, and PTV4D was defined as the union of the target volumes contoured on the ten phases of the 4DCT images. The centroid positions, volumetric differences, and dice similarity coefficients were evaluated for all PTVs. Results: The median centroid shifts between PTV3D and PTV4D and between PTVconv and PTV4D in all three dimensions were <0.3 cm for the three groups. The median size ratios of PTV4D to PTV3D were 0.80, 0.88, and 0.71, and PTV4D to PTVconv were 0.67, 0.73, and 0.76 (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The dice similarity coefficients were 0.87, 0.90, and 0.81 between PTV4D and PTV3D and 0.80, 0.84, and 0.83 between PTV4D and PTVconv (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The difference between the degree of inclusion of PTV4D in PTV3D and that of PTV4D in PTVconv was <2% for all groups. Compared with PTVconv, the amount of irradiated normal tissue

  19. Impact of PET/CT on the treatment planning and target volume delineation of radiotherapy in the patients with non-small-cell lung cancer complicated by atelectasis

    International Nuclear Information System (INIS)

    Objective: To investigate the impact of PET/CT on the treatment planning and target volume delineation of radiotherapy in patients with NSCLC complicated by atelectasis. Methods: Pre-treatment PET/CT scans were performed in 36 patients with pathologically proven NSCLC complicated by atelectasis of different severity undergoing curative 3D-CRT planning. Clinical staging before and after PET/CT was compared and the change of treatment plan was evaluated. The target volumes were delineated by CT and PET/CT. Results: PET/CT results changed the clinical staging in 18 (50.0%, 18/36) patients. PET/CT identified distant metastatic diseases in 11 (30.6%, 11/36) patients, thus excluding their eligibility for curative 3D-CRT. Of these 11 patients, managements were changed to palliative radiotherapy in 3 patients, chemotherapy in 7 patients and best supportive therapy in 1 patient. In the 25 patients with curative 3D-CRT, PET/CT altered the radiotherapy volume in 21 cases, including 12 with volume reduction, 7 with volume enlargement and 2 with location change. Three patients were given additional conventional radiotherapy, since PET/CT indicated supraclavicular nodal metastases. In the 3 patients with palliative 3D-CRT, 2 had target volume reduction and 1 had target volume enlargement after PET/CT. Conclusions: PET/CT may play a role in the management of patients with NSCLC complicated by atelectasis. It is also helpful for accurate delineation of target volume in 3D-CRT treatment planning. (authors)

  20. Defining the Optimal Planning Target Volume in Image-Guided Stereotactic Radiosurgery of Brain Metastases: Results of a Randomized Trial

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, John P., E-mail: john.kirkpatrick@dm.duke.edu [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States); Wang, Zhiheng [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Sampson, John H. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Surgery, Duke University, Durham, North Carolina (United States); McSherry, Frances; Herndon, James E. [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina (United States); Allen, Karen J.; Duffy, Eileen [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Hoang, Jenny K. [Department of Radiology, Duke University, Durham, North Carolina (United States); Chang, Zheng; Yoo, David S.; Kelsey, Chris R.; Yin, Fang-Fang [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States)

    2015-01-01

    Purpose: To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. Methods and Materials: Adult patients with 1 to 3 brain metastases less than 4 cm in greatest dimension, no previous brain radiation therapy, and Karnofsky performance status (KPS) above 70 were eligible for this institutional review board–approved trial. Individual lesions were randomized to 1- or 3- mm uniform expansion of the GTV defined on contrast-enhanced magnetic resonance imaging (MRI). The resulting planning target volume (PTV) was treated to 24, 18, or 15 Gy marginal dose for maximum PTV diameters less than 2, 2 to 2.9, and 3 to 3.9 cm, respectively, using a linear accelerator–based image-guided system. The primary endpoint was local recurrence (LR). Secondary endpoints included neurocognition Mini-Mental State Examination, Trail Making Test Parts A and B, quality of life (Functional Assessment of Cancer Therapy-Brain), radionecrosis (RN), need for salvage radiation therapy, distant failure (DF) in the brain, and overall survival (OS). Results: Between February 2010 and November 2012, 49 patients with 80 brain metastases were treated. The median age was 61 years, the median KPS was 90, and the predominant histologies were non–small cell lung cancer (25 patients) and melanoma (8). Fifty-five, 19, and 6 lesions were treated to 24, 18, and 15 Gy, respectively. The PTV/GTV ratio, volume receiving 12 Gy or more, and minimum dose to PTV were significantly higher in the 3-mm group (all P<.01), and GTV was similar (P=.76). At a median follow-up time of 32.2 months, 11 patients were alive, with median OS 10.6 months. LR was observed in only 3 lesions (2 in the 1 mm group, P=.51), with 6.7% LR 12 months after SRS. Biopsy-proven RN alone was observed in 6 lesions (5 in the 3-mm group, P=.10). The 12-month DF rate was 45.7%. Three months after SRS, no significant change in

  1. Investigation on the role of integrated PET/MRI for target volume definition and radiotherapy planning in patients with high grade glioma

    International Nuclear Information System (INIS)

    Purpose: To evaluate the impact of fluid-attenuated-inversion-recovery MRI (FLAIR/MRI) and Carbon-11-labeled-methionine PET (11C-MET-PET) on high grade glioma (HGG) tumor volume delineation for radiotherapy planning. Material and methods: Sixty-nine patients with HGG were evaluated. The clinical target volumes (CTV1, generated by adding a 10 mm margin to FLAIRMRI area, CTV2 by adding a 20 mm margin to enhanced T1MRI) and biological target volume (BTV) were delineated on pre-operative MRI images and 11CMETPET respectively. Results: The overlap between CTV1 and CTV2 showed a low correlation between the two volumes with CTV1 not always fully included into the CTV2. In all cases the whole BTV was included into the CTV1, while in 35/69 patients (50%) part of BTV was outside the CTV2 despite larger margins were added. In all cases recurrences were within the CTV1 volume and in 19/38 (50%) partially outside the CTV2. In all patients relapse corresponded to the BTV area. Conclusions: Our data suggest that the target volume definition using FLAIR–MRI is more adequate compared to enhanced T1MRI. 11C-METPET uptake could help identify microscopic residual areas

  2. Residual Tumor After Neoadjuvant Chemoradiation Outside the Radiation Therapy Target Volume: A New Prognostic Factor for Survival in Esophageal Cancer

    International Nuclear Information System (INIS)

    Purpose/Objective(s): The aim of this study was to analyze the accuracy of gross tumor volume (GTV) delineation and clinical target volume (CTV) margins for neoadjuvant chemoradiation therapy (neo-CRT) in esophageal carcinoma at pathologic examination and to determine the impact on survival. Methods and Materials: The study population consisted of 63 esophageal cancer patients treated with neo-CRT. GTV and CTV borders were demarcated in situ during surgery on the esophagus, using anatomical reference points to provide accurate information regarding tumor location at pathologic evaluation. To identify prognostic factors for disease-free survival (DFS) and overall survival (OS), a Cox regression analysis was performed. Results: After resection, macroscopic residual tumor was found outside the GTV in 7 patients (11%). Microscopic residual tumor was located outside the CTV in 9 patients (14%). The median follow-up was 15.6 months. With multivariate analysis, only microscopic tumor outside the CTV (hazard ratio [HR], 4.96; 95% confidence interval [CI], 1.03-15.36), and perineural growth (HR, 5.77; 95% CI, 1.27-26.13) were identified as independent prognostic factors for OS. The 1-year OS was 20% for patients with tumor outside the CTV and 86% for those without (P<.01). For DFS, microscopic tumor outside the CTV (HR, 5.92; 95% CI, 1.89-18.54) and ypN+ (HR, 3.36; 95% CI, 1.33-8.48) were identified as independent adverse prognostic factors. The 1-year DFS was 23% versus 77% for patients with or without tumor outside the CTV (P<.01). Conclusions: Microscopic tumor outside the CTV is associated with markedly worse OS after neo-CRT. This may either stress the importance of accurate tumor delineation or reflect aggressive tumor behavior requiring new adjuvant treatment modalities

  3. A dimensionless dynamic contrast enhanced MRI parameter for intra-prostatic tumour target volume delineation: initial comparison with histology

    Science.gov (United States)

    Hrinivich, W. Thomas; Gibson, Eli; Gaed, Mena; Gomez, Jose A.; Moussa, Madeleine; McKenzie, Charles A.; Bauman, Glenn S.; Ward, Aaron D.; Fenster, Aaron; Wong, Eugene

    2014-03-01

    Purpose: T2 weighted and diffusion weighted magnetic resonance imaging (MRI) show promise in isolating prostate tumours. Dynamic contrast enhanced (DCE)-MRI has also been employed as a component in multi-parametric tumour detection schemes. Model-based parameters such as Ktrans are conventionally used to characterize DCE images and require arterial contrast agent (CR) concentration. A robust parameter map that does not depend on arterial input may be more useful for target volume delineation. We present a dimensionless parameter (Wio) that characterizes CR wash-in and washout rates without requiring arterial CR concentration. Wio is compared to Ktrans in terms of ability to discriminate cancer in the prostate, as demonstrated via comparison with histology. Methods: Three subjects underwent DCE-MRI using gadolinium contrast and 7 s imaging temporal resolution. A pathologist identified cancer on whole-mount histology specimens, and slides were deformably registered to MR images. The ability of Wio maps to discriminate cancer was determined through receiver operating characteristic curve (ROC) analysis. Results: There is a trend that Wio shows greater area under the ROC curve (AUC) than Ktrans with median AUC values of 0.74 and 0.69 respectively, but the difference was not statistically significant based on a Wilcoxon signed-rank test (p = 0.13). Conclusions: Preliminary results indicate that Wio shows potential as a tool for Ktrans QA, showing similar ability to discriminate cancer in the prostate as Ktrans without requiring arterial CR concentration.

  4. Target volume for postoperative radiotherapy in non-small cell lung cancer: Results from a prospective trial

    International Nuclear Information System (INIS)

    Background and purpose: A previous prospective trial reported that three-dimensional conformal postoperative radiotherapy (PORT) for pN2 NSCLC patients using a limited clinical target volume (CTV) had a late morbidity rate and pulmonary function that did not differ from those observed in pN1 patients treated with surgery without PORT. The aim of this study was to assess locoregional control and localization of failure in patients treated with PORT. Materials and methods: The pattern of locoregional failure was evaluated retrospectively in 151 of 171 patients included in the PORT arm. The CTV included the involved lymph node stations and those with a risk of invasion >10%. Competing risk analysis was used to assess the incidence of locoregional failure and its location outside the CTV. Results: Overall survival at 5 years was 27.1% with a median follow-up of 67 months for 40 living patients. The 5-year cumulative incidence of locoregional failure was 19.4% (95% CI: 18.2–20.5%) including a failure rate of 2% (95% CI: 0–17%) in locations outside or at the border of the CTV. Conclusions: The use of limited CTV was associated with acceptable risk of geographic miss. Overall locoregional control was similar to that reported by other studies using PORT for pN2 patients

  5. Influence of experience and qualification on PET-based target volume delineation. When there is no expert - ask your colleague

    Energy Technology Data Exchange (ETDEWEB)

    Doll, C.; Grosu, A.L.; Nestle, U. [University Medical Center Freiburg, Radiation Oncology Department, Freiburg/Breisgau (Germany); Duncker-Rohr, V. [University Medical Center Freiburg, Radiation Oncology Department, Freiburg/Breisgau (Germany); Ortenau Clinical Center Offenburg, Radiation Oncology Department, Offenburg (Germany); Ruecker, G. [University of Freiburg, Institute of Medical Biometry und Medical Informatics, Freiburg (Germany); Mix, M. [University Medical Center Freiburg, Nuclear Medicine Department, Freiburg (Germany); MacManus, M. [University of Melbourne, The Sir Peter MacCallum Department of Oncology, Melbourne (Australia); Ruysscher, D. de [University Hospital Leuven/KU Leuven, Department of Radiation Oncology, Leuven (Belgium); Vogel, W. [Antoni van Leeuwenhoek Hospital, Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam (Netherlands); Eriksen, J.G. [Odense University Hospital, Department of Oncology, Odense (Denmark); Oyen, W. [Radboud University Nijmegen Medical Center, Department of Nuclear Medicine, Nijmegen (Netherlands); Weber, W. [University Medical Center Freiburg, Nuclear Medicine Department, Freiburg (Germany); Memorial Sloan-Kettering Cancer Center, Department of Radiology/Molecular Imaging and Therapy Service, New York (United States)

    2014-06-15

    The integration of positron emission tomography (PET) information for target volume delineation in radiation treatment planning is routine in many centers. In contrast to automatic contouring, research on visual-manual delineation is scarce. The present study investigates the dependency of manual delineation on experience and qualification. A total of 44 international interdisciplinary observers each defined a [{sup 18}F]fluorodeoxyglucose (FDG)-PET based gross tumor volume (GTV) using the same PET/CT scan from a patient with lung cancer. The observers were ''experts'' (E; n = 3), ''experienced interdisciplinary pairs'' (EP; 9 teams of radiation oncologist (RO) + nuclear medicine physician (NP)), ''single field specialists'' (SFS; n = 13), and ''students'' (S; n = 10). Five automatic delineation methods (AM) were also included. Volume sizes and concordance indices within the groups (pCI) and relative to the experts (eCI) were calculated. E (pCI = 0.67) and EP (pCI = 0.53) showed a significantly higher agreement within the groups as compared to SFS (pCI = 0.43, p = 0.03, and p = 0.006). In relation to the experts, EP (eCI = 0.55) showed better concordance compared to SFS (eCI = 0.49) or S (eCI = 0.47). The intermethod variability of the AM (pCI = 0.44) was similar to that of SFS and S, showing poorer agreement with the experts (eCI = 0.35). The results suggest that interdisciplinary cooperation could be beneficial for consistent contouring. Joint delineation by a radiation oncologist and a nuclear medicine physician showed remarkable agreement and better concordance with the experts compared to other specialists. The relevant intermethod variability of the automatic algorithms underlines the need for further standardization and optimization in this field. (orig.) [German] Die Daten aus der Positronenemissionstomographie (PET) werden in vielen Kliniken routinemaessig zur

  6. Influence of experience and qualification on PET-based target volume delineation. When there is no expert--ask your colleague

    DEFF Research Database (Denmark)

    Doll, C; Duncker-Rohr, V; Rücker, G;

    2014-01-01

    BACKGROUND AND PURPOSE: The integration of positron emission tomography (PET) information for target volume delineation in radiation treatment planning is routine in many centers. In contrast to automatic contouring, research on visual-manual delineation is scarce. The present study investigates ...

  7. Delineation of target volumes and organs at risk in adjuvant radiotherapy of early breast cancer: national guidelines and contouring atlas by the Danish Breast Cancer Cooperative Group

    DEFF Research Database (Denmark)

    Nielsen, Mette H; Berg, Martin; Pedersen, Anders N;

    2013-01-01

    During the past decade planning of adjuvant radiotherapy (RT) of early breast cancer has changed from two-dimensional (2D) to 3D conformal techniques. In the planning computerised tomography (CT) scan both the targets for RT and the organs at risk (OARs) are visualised, enabling an increased focu...... on target dose coverage and homogeneity with only minimal dose to the OARs. To ensure uniform RT in the national prospective trials of the Danish Breast Cancer Cooperative Group (DBCG), a national consensus for the delineation of clinical target volumes (CTVs) and OARs was required....

  8. Definition of the planning target volume of organs at risk (planning organ at risk volume, PRV) in case of radiotherapy of the ORL sphere; Definition d'un volume cible previsionnel d'organe a risque (Planning organ at risk volume, PRV) en cas de radiotherapie de la sphere ORL

    Energy Technology Data Exchange (ETDEWEB)

    Louvel, G.; Le Prise, E.; Williaume, D.; De Crevoisier, R. [Centre Eugene-Marquis, 35 - Rennes (France); Cazoulat, G.; Lafond, C.; Simon, A.; Haigron, P.; De Crevoisier, R. [Universite de Rennes 1 LTSI, 35 - Rennes (France); Inserm U642, 35 - Rennes (France); Li, B.S. [Shandong Cancer Hospital, Jinan (China); Boisselier, P. [Centre Val d' Aurelle, 34 - Montpellier (France)

    2010-10-15

    The authors report a study which aimed at quantifying anatomic variations of organs at risk and their dosimetric impact, and at computing appropriate margins around organs at risk to generate planning target volumes of organs at risk, representative of the dose delivered to organs at risk. Nine patients have been treated for a locally advanced ORL cancer by a concomitant combination of radiotherapy and chemotherapy, with weekly scanographies during the radiotherapy. Registration has been successfully performed according to three bone references. Volume modifications and motions have been computed to define the margins around three organs at risk. Short communication

  9. SU-E-J-192: Verification of 4D-MRI Internal Target Volume Using Cine MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lafata, K; Czito, B; Palta, M; Bashir, M; Yin, F; Cai, J [Duke University Medical Center, Durham, NC (United States)

    2014-06-01

    Purpose: To investigate the accuracy of 4D-MRI in determining the Internal Target Volume (ITV) used in radiation oncology treatment planning of liver cancers. Cine MRI is used as the standard baseline in establishing the feasibility and accuracy of 4D-MRI tumor motion within the liver. Methods: IRB approval was obtained for this retrospective study. Analysis was performed on MR images from four patients receiving external beam radiation therapy for liver cancer at our institution. Eligible patients received both Cine and 4D-MRI scans before treatment. Cine images were acquired sagittally in real time at a slice bisecting the tumor, while 4D images were acquired volumetrically. Cine MR DICOM headers were manipulated such that each respiratory frame was assigned a unique slice location. This approach permitted the treatment planning system (Eclipse, Varian Medical Systems) to recognize a complete respiratory cycle as a “volume”, where the gross tumor was contoured temporally. Software was developed to calculate the union of all frame contours in the structure set, resulting in the corresponding plane of the ITV projecting through the middle of the tumor, defined as the Internal Target Area (ITA). This was repeated for 4D-MRI, at the corresponding slice location, allowing a direct comparison of ITAs obtained from each modality. Results: Four patients have been analyzed. ITAs contoured from 4D-MRI correlate with contours from Cine MRI. The mean error of 4D values relative to Cine values is 7.67 +/− 2.55 %. No single ITA contoured from 4D-MRI demonstrated more than 10.5 % error compared to its Cine MRI counterpart. Conclusion: Motion management is a significant aspect of treatment planning within dynamic environments such as the liver, where diaphragmatic and cardiac activity influence plan accuracy. This small pilot study suggests that 4D-MRI based ITA measurements agree with Cine MRI based measurements, an important step towards clinical implementation. NIH 1R21

  10. The New York Head-A precise standardized volume conductor model for EEG source localization and tES targeting.

    Science.gov (United States)

    Huang, Yu; Parra, Lucas C; Haufe, Stefan

    2016-10-15

    In source localization of electroencephalograpic (EEG) signals, as well as in targeted transcranial electric current stimulation (tES), a volume conductor model is required to describe the flow of electric currents in the head. Boundary element models (BEM) can be readily computed to represent major tissue compartments, but cannot encode detailed anatomical information within compartments. Finite element models (FEM) can capture more tissue types and intricate anatomical structures, but with the higher precision also comes the need for semi-automated segmentation, and a higher computational cost. In either case, adjusting to the individual human anatomy requires costly magnetic resonance imaging (MRI), and thus head modeling is often based on the anatomy of an 'arbitrary' individual (e.g. Colin27). Additionally, existing reference models for the human head often do not include the cerebro-spinal fluid (CSF), and their field of view excludes portions of the head and neck-two factors that demonstrably affect current-flow patterns. Here we present a highly detailed FEM, which we call ICBM-NY, or "New York Head". It is based on the ICBM152 anatomical template (a non-linear average of the MRI of 152 adult human brains) defined in MNI coordinates, for which we extended the field of view to the neck and performed a detailed segmentation of six tissue types (scalp, skull, CSF, gray matter, white matter, air cavities) at 0.5mm(3) resolution. The model was solved for 231 electrode locations. To evaluate its performance, additional FEMs and BEMs were constructed for four individual subjects. Each of the four individual FEMs (regarded as the 'ground truth') is compared to its BEM counterpart, the ICBM-NY, a BEM of the ICBM anatomy, an 'individualized' BEM of the ICBM anatomy warped to the individual head surface, and FEMs of the other individuals. Performance is measured in terms of EEG source localization and tES targeting errors. Results show that the ICBM-NY outperforms

  11. The New York Head-A precise standardized volume conductor model for EEG source localization and tES targeting.

    Science.gov (United States)

    Huang, Yu; Parra, Lucas C; Haufe, Stefan

    2016-10-15

    In source localization of electroencephalograpic (EEG) signals, as well as in targeted transcranial electric current stimulation (tES), a volume conductor model is required to describe the flow of electric currents in the head. Boundary element models (BEM) can be readily computed to represent major tissue compartments, but cannot encode detailed anatomical information within compartments. Finite element models (FEM) can capture more tissue types and intricate anatomical structures, but with the higher precision also comes the need for semi-automated segmentation, and a higher computational cost. In either case, adjusting to the individual human anatomy requires costly magnetic resonance imaging (MRI), and thus head modeling is often based on the anatomy of an 'arbitrary' individual (e.g. Colin27). Additionally, existing reference models for the human head often do not include the cerebro-spinal fluid (CSF), and their field of view excludes portions of the head and neck-two factors that demonstrably affect current-flow patterns. Here we present a highly detailed FEM, which we call ICBM-NY, or "New York Head". It is based on the ICBM152 anatomical template (a non-linear average of the MRI of 152 adult human brains) defined in MNI coordinates, for which we extended the field of view to the neck and performed a detailed segmentation of six tissue types (scalp, skull, CSF, gray matter, white matter, air cavities) at 0.5mm(3) resolution. The model was solved for 231 electrode locations. To evaluate its performance, additional FEMs and BEMs were constructed for four individual subjects. Each of the four individual FEMs (regarded as the 'ground truth') is compared to its BEM counterpart, the ICBM-NY, a BEM of the ICBM anatomy, an 'individualized' BEM of the ICBM anatomy warped to the individual head surface, and FEMs of the other individuals. Performance is measured in terms of EEG source localization and tES targeting errors. Results show that the ICBM-NY outperforms

  12. What's new in target volume definition for radiologists in ICRU Report 71? How can the ICRU volume definitions be integrated in clinical practice?

    DEFF Research Database (Denmark)

    Berthelsen, Anne Kiil; Dobbs, Jane; Kjellén, Elisabeth;

    2007-01-01

    The optimal definition of the size, shape and location of gross tumour volume is one of the most important steps in the planning of radiation therapy, and necessitates a proper understanding of the procedure from both the oncologic radiologist and the radiation oncologist. This overview reports...

  13. Mapping Patterns of Ipsilateral Supraclavicular Nodal Metastases in Breast Cancer: Rethinking the Clinical Target Volume for High-risk Patients

    Energy Technology Data Exchange (ETDEWEB)

    Jing, Hao [Department of Radiation Oncology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Wang, Shu-Lian, E-mail: wsl20040118@yahoo.com [Department of Radiation Oncology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Li, Jing; Xue, Mei; Xiong, Zu-Kun [Department of Radiology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Jin, Jing; Wang, Wei-Hu; Song, Yong-Wen; Liu, Yue-Ping; Ren, Hua; Fang, Hui; Yu, Zi-Hao; Liu, Xin-Fan [Department of Radiation Oncology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Li, Ye-Xiong, E-mail: yexiong12@163.com [Department of Radiation Oncology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

    2015-10-01

    Purpose: To map the location of metastatic supraclavicular (SCV) lymph nodes (LNMs) in breast cancer patients with SCV node involvement and determine whether and where the radiation therapy clinical target volume (CTV) of this region could be modified in high-risk subsets. Methods and Materials: Fifty-five patients with metastatic SCV LNMs were eligible for geographic mapping and atlas coverage analysis. All LNMs and their epicenters were registered proportionally by referencing the surrounding landmarks onto simulation computed tomography images of a standard patient. CTVs based on selected SCV atlases, including the one by the Radiation Therapy Oncology Group (RTOG) were contoured. A modified SCV CTV was tried and shown to have better involved-node coverage and thus theoretically improved prophylaxis in this setting. Results: A total of 50 (91%) and 45 (81.8%) patients had LNMs in the medial and lateral SCV subregions, respectively. Also, 36 patients (65.5%) had LNMs located at the junction of the jugular-subclavian veins. All nodes were covered in only 25.5% to 41.8% of patients by different atlases. The RTOG atlas covered all nodes in 25.5% of patients. Stratified by the nodes in all the patients as a whole, 49.2% to 81.3% were covered, and the RTOG atlas covered 62.6%. The lateral and posterior borders were the most overlooked locations. Modification by extending the borders to natural anatomic barriers allowed the new CTV to cover all the nodes in 81.8% of patients and encompass 96.1% of all the nodes. Conclusions: According to the distribution of SCV LNMs, the extent of existing atlases might not be adequate for potential metastatic sites in certain groups of patients. The extension of the lateral and posterior CTV borders in high-risk or recurrent patients might be a reasonable approach for increasing coverage. However, additional data in more homogeneous populations with localized disease are needed before routine application.

  14. Impact of 18F-FDG PET/CT on target volume delineation in recurrent or residual gynaecologic carcinoma

    OpenAIRE

    Vees Hansjörg; Casanova Nathalie; Zilli Thomas; Imperiano Hestia; Ratib Osman; Popowski Youri; Wang Hui; Zaidi Habib; Miralbell Raymond

    2012-01-01

    Abstract Background To evaluate the impact of 18F-FDG PET/CT on target volume delineation in gynaecological cancer. Methods F-FDG PET/CT based RT treatment planning was performed in 10 patients with locally recurrent (n = 5) or post-surgical residual gynaecological cancer (n = 5). The gross tumor volume (GTV) was defined by 4 experienced radiation oncologists first using contrast enhanced CT (GTVCT) and secondly using the fused 18F-FDG PET/CT datasets (GTVPET/CT). In addition, the GTV was del...

  15. Comparison of Five Segmentation Tools for 18F-Fluoro-Deoxy-Glucose-Positron Emission Tomography-Based Target Volume Definition in Head and Neck Cancer

    International Nuclear Information System (INIS)

    Purpose: Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with 18F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may improve definition of the gross tumor volume (GTV). In this study, five methods for tumor delineation on FDG-PET are compared with CT-based delineation. Methods and Materials: Seventy-eight patients with Stages II-IV squamous cell carcinoma of the head and neck area underwent coregistered CT and FDG-PET. The primary tumor was delineated on CT, and five PET-based GTVs were obtained: visual interpretation, applying an isocontour of a standardized uptake value of 2.5, using a fixed threshold of 40% and 50% of the maximum signal intensity, and applying an adaptive threshold based on the signal-to-background ratio. Absolute GTV volumes were compared, and overlap analyses were performed. Results: The GTV method of applying an isocontour of a standardized uptake value of 2.5 failed to provide successful delineation in 45% of cases. For the other PET delineation methods, volume and shape of the GTV were influenced heavily by the choice of segmentation tool. On average, all threshold-based PET-GTVs were smaller than on CT. Nevertheless, PET frequently detected significant tumor extension outside the GTV delineated on CT (15-34% of PET volume). Conclusions: The choice of segmentation tool for target-volume definition of head and neck cancer based on FDG-PET images is not trivial because it influences both volume and shape of the resulting GTV. With adequate delineation, PET may add significantly to CT- and physical examination-based GTV definition

  16. Recommendations for the target volume definition on dosimetry scanning in the oropharynx cancers; Recommandations pour la definition d'un volume cible sur scanographie dosimetrique dans les cancers de l'oropharynx

    Energy Technology Data Exchange (ETDEWEB)

    Maingon, P. [Centre Georges-Francois-Leclerc, Dept. de Radiotherapie, 21 - Dijon (France); Gregoire, V. [Hopital Universitaire Saint Luc, Dept. d' Oncologie Radiotherapie et Lab. de Radiologie, Brussels (Belgium)

    2004-11-01

    The oropharynx includes the base of tongue, tonsil pillars, soft palate, lateral and posterior wall of the hypopharynx. Tumors involving each part of these areas are often treated by external beam radiation therapy. The development of conformal approaches and the implementation of intensity modulated radiation therapy, combined with accurate definition of target volumes, endorsed by the international community, allows to propose guidelines for definition of target volumes. First of all imaging acquisition for dosimetry is reminded. For tumors involving the base of tongue and vallecula, early superficial tumors should be distinguished from tumors involving the muscles, indicating an increased margin defining the clinical target volume around the tumor to 1.5 cm. Tumors developed in the posterior wall of the hypopharynx should include constrictor muscles of the pharynx inside of the CTV. Tonsil carcinomas should be treated with a 1.5 cm margin around the tumor in the three dimensions. In spite of modern imaging, external beam treatment of tumors developed in the soft palate and in palatine arch remains difficult. The high rate of nodal involvement of these tumors and significant rates of bilateral extension have to be taken into consideration. Accurate criteria have been available to integrate a probability of bilateral extension in oropharynx 1 tumors. It should be analyzed according to the size of the tumor and the rate of extension in the base of the tongue and in the palatine arch. (authors)

  17. Prospective comparative evaluation of planning target volume margin for brain intensity modulated radiotherapy utilizing hybrid online imaging modalities

    Directory of Open Access Journals (Sweden)

    Sayan Paul

    2015-01-01

    Full Text Available Background: A new advancement in daily monitoring of patient positioning is the use of hybrid technologies where two separate online imaging modalities are integrated to achieve precise treatment delivery. Our center has a set-up that integrates Elekta Linear accelerator device (EPID with BrainLAB ExacTrac imaging for the first time in the world. We calculated planning target volume (PTV margin for brain radiotherapy with thermoplastic mask immobilization with conventional EPID and BrainLAB ExacTrac image guidance system. Materials and Methods: EPID (iViewGT and ExacTrac verification images of 32 patients in total 784 radiotherapy sessions were acquired and analyzed. Systematic (Σ and random errors (σ were calculated in cranio-caudal, lateral and anteroposterior directions. PTV margins calculated using van Herk (2.5 Σ +0.7 σ formula for each imaging system. Result: Of total 784 sessions EPID image were obtained in 723 sessions, ExacTrac obtained in 431 sessions. In cranio-caudal direction, the systematic error, random error, and the calculated PTV margin were 0.09 cm, 0.12 cm, and 0.31 cm, respectively, with EPID image and 0.17 cm, 0.13 cm, and 0.51 cm, respectively, with ExacTrac. The corresponding values in lateral direction were 0.11 cm, 0.15 cm, and 0.40 cm with EPID and 0.16 cm, 0.10 cm, and 0.47 cm, respectively, with ExacTrac image. The same parameters for anteroposterior were 0.10 cm, 0.13 cm, 0.37 cm with EPID and 0.144 cm, 0.10 cm, and 0.43 cm with ExacTrac image. Pearson's correlation coefficient was found to be 0.66, 0.67, 0.62 in these three directions. Conclusion: With dual imaging modalities, our calculated adequate PTV margin for brain radiotherapy cases are 0.51 cm, 0.47 cm, is 0.43 cm in cranio-caudal, right-left, and anteroposterior directions, respectively.

  18. Monte-Carlo model development for evaluation of current clinical target volume definition for heterogeneous and hypoxic glioblastoma

    Science.gov (United States)

    Moghaddasi, L.; Bezak, E.; Harriss-Phillips, W.

    2016-05-01

    Clinical target volume (CTV) determination may be complex and subjective. In this work a microscopic-scale tumour model was developed to evaluate current CTV practices in glioblastoma multiforme (GBM) external radiotherapy. Previously, a Geant4 cell-based dosimetry model was developed to calculate the dose deposited in individual GBM cells. Microscopic extension probability (MEP) models were then developed using Matlab-2012a. The results of the cell-based dosimetry model and MEP models were combined to calculate survival fractions (SF) for CTV margins of 2.0 and 2.5 cm. In the current work, oxygenation and heterogeneous radiosensitivity profiles were incorporated into the GBM model. The genetic heterogeneity was modelled using a range of α/β values (linear-quadratic model parameters) associated with different GBM cell lines. These values were distributed among the cells randomly, taken from a Gaussian-weighted sample of α/β values. Cellular oxygen pressure was distributed randomly taken from a sample weighted to profiles obtained from literature. Three types of GBM models were analysed: homogeneous-normoxic, heterogeneous-normoxic, and heterogeneous-hypoxic. The SF in different regions of the tumour model and the effect of the CTV margin extension from 2.0–2.5 cm on SFs were investigated for three MEP models. The SF within the beam was increased by up to three and two orders of magnitude following incorporation of heterogeneous radiosensitivities and hypoxia, respectively, in the GBM model. However, the total SF was shown to be overdominated by the presence of tumour cells in the penumbra region and to a lesser extent by genetic heterogeneity and hypoxia. CTV extension by 0.5 cm reduced the SF by a maximum of 78.6  ±  3.3%, 78.5  ±  3.3%, and 77.7  ±  3.1% for homogeneous and heterogeneous-normoxic, and heterogeneous hypoxic GBMs, respectively. Monte-Carlo model was developed to quantitatively evaluate SF for genetically

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

    Science.gov (United States)

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

    2007-02-01

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

  20. Evaluation of variability in target volume delineation for newly diagnosed glioblastoma: a multi-institutional study from the Korean Radiation Oncology Group

    International Nuclear Information System (INIS)

    This study aimed for a collaborative evaluation of variability in the target volumes for glioblastoma, determined and contoured by different radiotherapy (RT) facilities in Korea. Fifteen panels of radiation oncologists from independent institutions contoured the gross target volumes (GTVs) and clinical target volumes (CTVs) for 3-dimensional conformal RT or intensity-modulated RT on each simulation CT images, after scrutinizing the enhanced T1-weighted and T2-weighted-fluid-attenuated inversion recovery MR images of 9 different cases of glioblastoma. Degrees of contouring agreement were analyzed by the kappa statistics. Using the algorithm of simultaneous truth and performance level estimation (STAPLE), GTVSTAPLE and CTVSTAPLE contours were derived. Contour agreement was moderate (mean kappa 0.58) among the GTVs and was substantial (mean kappa 0.65) among the CTVs. However, each panels’ GTVs and modification of CTVs regarding anatomical structures varied. Three-fourth of contoured panels’ CTVs encompassed the peritumoral areas of T2-high signal intensity (T2-HSI). Nine of nine GTVSTAPLE encompased the surgical cavity and the T1-enhanced lesions. Eight of nine CTVSTAPLE encompassed the peritumoral T2-HSI area. The median MARGIN90 and the median MARGIN95 were 1.4 cm and 1.5 cm, respectively. Moderate to substantial agreement existed in target volumes for 3-dimensional or intensity-modulated RT determined by radiation oncologists in Korea. According to the estimated consensus contours, the initial CTV encompassed the GTV with margin less than 2.0 cm and the whole peritumoral areas of T2-HSI. The findings of our study propose the need for further studies and modified guidelines. The online version of this article (doi:10.1186/s13014-015-0439-z) contains supplementary material, which is available to authorized users

  1. Efficacy of the smaller target volume for stage III non-small cell lung cancer treated with intensity-modulated radiotherapy

    OpenAIRE

    LIANG, XIANGCUN; Yu, Huiming; Yu, Rong; Xu, Gang; Guangying ZHU

    2015-01-01

    The present study reports the local recurrence, distant metastasis, progression-free survival, overall survival and radiation toxicity between two arms of stage III non-small cell lung cancer (NSCLC) treated with intensity-modulated radiotherapy (IMRT); one arm with clinical target volume (CTV) and the other without CTV. The two arms of local recurrence, distant metastasis, progression-free survival, overall survival, grade 3–4 radiation esophagitis and hematological toxicity had no statistic...

  2. Comparison of planning target volumes based on three-dimensional CT and four-dimensional CT simulation images of non-small-cell lung cancer

    International Nuclear Information System (INIS)

    Objective: To compare the positional and volumetric differences of planning target volumes (PTVs) based on axial three-dimensional CT (3D-CT) and four-dimensional CT (4D-CT) for the primary tumor of non-small cell lung cancer (NSCLC). Methods: Sixteen NSCLC patients with lesions located in the upper lobe and 12 patients with lesions in middle and lower lobes, totally 28 patients, initially underwent three-dimensional CT scans followed by 4D-CT scans of the thorax under normal free breathing. PTVvector was defined on gross tumor volume (GTV) contoured on 3D-CT and its motion vector. The clinical target volumes (CTVs) were created by adding 7 mm to GTVs, then, internal target volume (ITVs) were produced by enlarging CTVs isotropically based on the individually measured amount of motion in the 4D-CT, lastly, PTVs were created by adding 3 mm setup margin to ITVs. PTV4D was defined on the fusion of CTVs on all phases of the 4D data. The CTV wag generated by adding 7 mm to the GTV on each phase, then, PTVs were produced by fusing CTVs on 10 phases and adding 3 mm setup margin. The position of the target center, the volume of target and the degree of inclusion (DI) were compared reciprocally between the PTVvector and the PTV4D The difference of the position, volume and degree of inclusion of the targets between PTVvector and PTV4D were compared, and the relevance between the relative characters of the targets and the three-dimensional vector was analyzed based on the groups of the patients. Results: The median of the 3 D motion vector for the lesions in the upper lobe was 2.8 mm, significantly lower than that for the lesions in the middle and lower lobe (7.0 mm, z=-3.485, P<0.05). In the upper lobe group there was only significant spatial difference between the PTVvector and PTV4D targets in the center coordinate at the x axe (z=-2.010, P<0.05), while in the middle and lower lobes there was only significant spatial difference between the PTVvector and PTV4D targets in the

  3. The effect of irregular breathing patterns on internal target volumes in four-dimensional CT and cone-beam CT images in the context of stereotactic lung radiotherapy

    International Nuclear Information System (INIS)

    Purpose: Stereotactic lung radiotherapy is complicated by tumor motion from patient respiration. Four-dimensional CT (4DCT) imaging is a motion compensation method used in treatment planning to generate a maximum intensity projection (MIP) internal target volume (ITV). Image guided radiotherapy during treatment may involve acquiring a volumetric cone-beam CT (CBCT) image and visually aligning the tumor to the planning 4DCT MIP ITV contour. Moving targets imaged with CBCT can appear blurred and currently there are no studies reporting on the effect that irregular breathing patterns have on CBCT volumes and their alignment to 4DCT MIP ITV contours. The objective of this work was therefore to image a phantom moving with irregular breathing patterns to determine whether any configurations resulted in errors in volume contouring or alignment. Methods: A Perspex thorax phantom was used to simulate a patient. Three wooden “lung” inserts with embedded Perspex “lesions” were moved up to 4 cm with computer-generated motion patterns, and up to 1 cm with patient-specific breathing patterns. The phantom was imaged on 4DCT and CBCT with the same acquisition settings used for stereotactic lung patients in the clinic and the volumes on all phantom images were contoured. This project assessed the volumes for qualitative and quantitative changes including volume, length of the volume, and errors in alignment between CBCT volumes and 4DCT MIP ITV contours. Results: When motion was introduced 4DCT and CBCT volumes were reduced by up to 20% and 30% and shortened by up to 7 and 11 mm, respectively, indicating that volume was being under-represented at the extremes of motion. Banding artifacts were present in 4DCT MIP images, while CBCT volumes were largely reduced in contrast. When variable amplitudes from patient traces were used and CBCT ITVs were compared to 4DCT MIP ITVs there was a distinct trend in reduced ITV with increasing amplitude that was not seen when compared to

  4. Radiotherapy of large target volumes in Hodgkin's lymphoma: normal tissue sparing capability of forward IMRT versus conventional techniques

    International Nuclear Information System (INIS)

    This paper analyses normal tissue sparing capability of radiation treatment techniques in Hodgkin's lymphoma with large treatment volume. 10 patients with supradiaphragmatic Hodgkin's lymphoma and planning target volume (PTV) larger than 900 cm3 were evaluated. Two plans were simulated for each patient using 6 MV X-rays: a conventional multi-leaf (MLC) parallel-opposed (AP-PA) plan, and the same plan with additional MLC shaped segments (forward planned intensity modulated radiation therapy, FPIMRT). In order to compare plans, dose-volume histograms (DVHs) of PTV, lungs, heart, spinal cord, breast, and thyroid were analyzed. The Inhomogeneity Coefficient (IC), the PTV receiving 95% of the prescription dose (V95), the normal tissue complication probability (NTCP) and dose-volume parameters for the OARs were determined. the PTV coverage was improved (mean V95AP-PA = 95.9 and ICAP-PA = 0.4 vs. V95FPIMRT = 96.8 and ICFPIMRT = 0.31, p ≤ 0.05) by the FPIMRT technique compared to the conventional one. At the same time, NTCPs of lung, spinal cord and thyroid, and the volume of lung and thyroid receiving ≥ 30 Gy resulted significantly reduced when using the FPIMRT technique. The FPIMRT technique can represent a very useful and, at the same time, simple method for improving PTV conformity while saving critical organs when large fields are needed as in Hodgkin's lymphoma

  5. RTOG Sarcoma Radiation Oncologists Reach Consensus on Gross Tumor Volume (GTV) and Clinical Target Volume (CTV) on Computed Tomographic Images for Preoperative Radiotherapy of Primary Soft Tissue Sarcoma of Extremity in RTOG Studies

    Science.gov (United States)

    Wang, Dian; Bosch, Walter; Roberge, David; Finkelstein, Steven E.; Petersen, Ivy; Haddock, Michael; Chen, Yen-Lin E.; Saito, Naoyuki G.; Kirsch, David G.; Hitchcock, Ying J.; Wolfson, Aaron H.; DeLaney, Thomas F.

    2011-01-01

    Objective To develop an Radiation Therapy Oncology Group (RTOG) atlas delineating gross tumor volume (GTV), and clinical target volume (CTV) to be used for preoperative radiotherapy of primary extremity soft tissue sarcoma (STS). Methods A consensus meeting was held during the RTOG meeting in January 2010 to reach agreement about GTV and CTV delineation on CT images for preoperative radiotherapy of high-grade large extremity STS. Data were presented to address the local extension of STS. Extensive discussion ensued to develop optimal criteria for GTV and CTV delineation on CT images. Results A consensus was reached on appropriate CT-based GTV and CTV. GTV is gross tumor defined by T1 contrast-enhanced MRI images. Fusion of MRI and CT is recommended to delineate the GTV. CTV for high-grade large STS typically includes GTV plus 3 cm margins in the longitudinal directions. If this causes the field to extend beyond the compartment, the field can be shortened to include the end of a compartment. The radial margin from the lesion should be 1.5 cm including any portion of the tumor not confined by an intact fascial barrier, bone or skin surface. Conclusion The consensus on GTV and CTV for preoperative radiotherapy of high-grade large extremity STS is available as web-based images as well as descriptive format through the RTOG. This is expected to improve target volume consistency and allow for rigorous evaluation of the benefits and risks of such treatment. PMID:21676552

  6. The influence of target and patient characteristics on the volume obtained from cone beam CT in lung stereotactic body radiation therapy

    International Nuclear Information System (INIS)

    Purpose: To investigate the influence of tumor and patient characteristics on the target volume obtained from cone beam CT (CBCT) in lung stereotactic body radiation therapy (SBRT). Materials and methods: For a given cohort of 71 patients, the internal target volume (ITV) in CBCT obtained from four different datasets was compared with a reference ITV drawn on a four-dimensional CT (4DCT). The significance of the tumor size, location, relative target motion (RM) and patient’s body mass index (BMI) and gender on the adequacy of ITV obtained from CBCT was determined. Results: The median ITV-CBCT was found to be smaller than the ITV-4DCT by 11.8% (range: −49.8 to +24.3%, P < 0.001). Small tumors located in the lower lung were found to have a larger RM than large tumors in the upper lung. Tumors located near the central lung had high CT background which reduced the target contrast near the edges. Tumor location close to center vs. periphery was the only significant factor (P = 0.046) causing underestimation of ITV in CBCT, rather than RM (P = 0.323) and other factors. Conclusions: The current clinical study has identified that the location of tumor is a major source of discrepancy between ITV-CBCT and ITV-4DCT for lung SBRT

  7. A predictive model to guide management of the overlap region between target volume and organs at risk in prostate cancer volumetric modulated arc therapy

    International Nuclear Information System (INIS)

    The goal of this study is to determine whether the magnitude of overlap between planning target volume (PTV) and rectum (Rectumoverlap) or PTV and bladder (Bladderoverlap) in prostate cancer volumetric-modulated arc therapy (VMAT) is predictive of the dose-volume relationships achieved after optimization, and to identify predictive equations and cutoff values using these overlap volumes beyond which the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) dose-volume constraints are unlikely to be met. Fifty-seven patients with prostate cancer underwent VMAT planning using identical optimization conditions and normalization. The PTV (for the 50.4 Gy primary plan and 30.6 Gy boost plan) included 5 to 10 mm margins around the prostate and seminal vesicles. Pearson correlations, linear regression analyses, and receiver operating characteristic (ROC) curves were used to correlate the percentage overlap with dose-volume parameters. The percentage Rectumoverlap and Bladderoverlap correlated with sparing of that organ but minimally impacted other dose-volume parameters, predicted the primary plan rectum V45 and bladder V50 with R2 = 0.78 and R2 = 0.83, respectively, and predicted the boost plan rectum V30 and bladder V30 with R2 = 0.53 and R2 = 0.81, respectively. The optimal cutoff value of boost Rectumoverlap to predict rectum V75 >15% was 3.5% (sensitivity 100%, specificity 94%, p overlap to predict bladder V80 >10% was 5.0% (sensitivity 83%, specificity 100%, p < 0.01). The degree of overlap between PTV and bladder or rectum can be used to accurately guide physicians on the use of interventions to limit the extent of the overlap region prior to optimization.

  8. A predictive model to guide management of the overlap region between target volume and organs at risk in prostate cancer volumetric modulated arc therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mattes, Malcolm D.; Lee, Jennifer C.; Einaiem, Sara; Guirguis, Adel; Ikoro, N. C.; Ashamalla Hani [Dept. of Radiation Oncology, New York Methodist Hospital, Brooklyn (United States)

    2013-12-15

    The goal of this study is to determine whether the magnitude of overlap between planning target volume (PTV) and rectum (Rectum{sub overlap}) or PTV and bladder (Bladder{sub overlap}) in prostate cancer volumetric-modulated arc therapy (VMAT) is predictive of the dose-volume relationships achieved after optimization, and to identify predictive equations and cutoff values using these overlap volumes beyond which the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) dose-volume constraints are unlikely to be met. Fifty-seven patients with prostate cancer underwent VMAT planning using identical optimization conditions and normalization. The PTV (for the 50.4 Gy primary plan and 30.6 Gy boost plan) included 5 to 10 mm margins around the prostate and seminal vesicles. Pearson correlations, linear regression analyses, and receiver operating characteristic (ROC) curves were used to correlate the percentage overlap with dose-volume parameters. The percentage Rectum{sub overlap} and Bladder{sub overlap} correlated with sparing of that organ but minimally impacted other dose-volume parameters, predicted the primary plan rectum V{sub 45} and bladder V{sub 50} with R{sup 2} = 0.78 and R{sup 2} = 0.83, respectively, and predicted the boost plan rectum V{sub 30} and bladder V{sub 30} with R{sup 2} = 0.53 and R{sup 2} = 0.81, respectively. The optimal cutoff value of boost Rectumoverlap to predict rectum V75 >15% was 3.5% (sensitivity 100%, specificity 94%, p < 0.01), and the optimal cutoff value of boost Bladder{sub overlap} to predict bladder V{sub 80} >10% was 5.0% (sensitivity 83%, specificity 100%, p < 0.01). The degree of overlap between PTV and bladder or rectum can be used to accurately guide physicians on the use of interventions to limit the extent of the overlap region prior to optimization.

  9. Antagomirs targeting microRNA-134 increase hippocampal pyramidal neuron spine volume in vivo and protect against pilocarpine-induced status epilepticus.

    Science.gov (United States)

    Jimenez-Mateos, Eva M; Engel, Tobias; Merino-Serrais, Paula; Fernaud-Espinosa, Isabel; Rodriguez-Alvarez, Natalia; Reynolds, James; Reschke, Cristina R; Conroy, Ronan M; McKiernan, Ross C; deFelipe, Javier; Henshall, David C

    2015-07-01

    Emerging data support roles for microRNA (miRNA) in the pathogenesis of various neurologic disorders including epilepsy. MicroRNA-134 (miR-134) is enriched in dendrites of hippocampal neurons, where it negatively regulates spine volume. Recent work identified upregulation of miR-134 in experimental and human epilepsy. Targeting miR-134 in vivo using antagomirs had potent anticonvulsant effects against kainic acid-induced seizures and was associated with a reduction in dendritic spine number. In the present study, we measured dendritic spine volume in mice injected with miR-134-targeting antagomirs and tested effects of the antagomirs on status epilepticus triggered by the cholinergic agonist pilocarpine. Morphometric analysis of over 6,400 dendritic spines in Lucifer yellow-injected CA3 pyramidal neurons revealed increased spine volume in mice given antagomirs compared to controls that received a scrambled sequence. Treatment of mice with miR-134 antagomirs did not alter performance in a behavioral test (novel object location). Status epilepticus induced by pilocarpine was associated with upregulation of miR-134 within the hippocampus of mice. Pretreatment of mice with miR-134 antagomirs reduced the proportion of animals that developed status epilepticus following pilocarpine and increased animal survival. In antagomir-treated mice that did develop status epilepticus, seizure onset was delayed and total seizure power was reduced. These studies provide in vivo evidence that miR-134 regulates spine volume in the hippocampus and validation of the seizure-suppressive effects of miR-134 antagomirs in a model with a different triggering mechanism, indicating broad conservation of anticonvulsant effects.

  10. Use of combined maximum and minimum intensity projections to determine internal target volume in 4-dimensional CT scans for hepatic malignancies

    Directory of Open Access Journals (Sweden)

    Liu Jin

    2012-01-01

    Full Text Available Abstract Background To evaluate the accuracy of the combined maximum and minimum intensity projection-based internal target volume (ITV delineation in 4-dimensional (4D CT scans for liver malignancies. Methods 4D CT with synchronized IV contrast data were acquired from 15 liver cancer patients (4 hepatocellular carcinomas; 11 hepatic metastases. We used five approaches to determine ITVs: (1. ITVAllPhases: contouring gross tumor volume (GTV on each of 10 respiratory phases of 4D CT data set and combining these GTVs; (2. ITV2Phase: contouring GTV on CT of the peak inhale phase (0% phase and the peak exhale phase (50% and then combining the two; (3. ITVMIP: contouring GTV on MIP with modifications based on physician's visual verification of contours in each respiratory phase; (4. ITVMinIP: contouring GTV on MinIP with modification by physician; (5. ITV2M: combining ITVMIP and ITVMinIP. ITVAllPhases was taken as the reference ITV, and the metrics used for comparison were: matching index (MI, under- and over-estimated volume (Vunder and Vover. Results 4D CT images were successfully acquired from 15 patients and tumor margins were clearly discernable in all patients. There were 9 cases of low density and 6, mixed on CT images. After comparisons of metrics, the tool of ITV2M was the most appropriate to contour ITV for liver malignancies with the highest MI of 0.93 ± 0.04 and the lowest proportion of Vunder (0.07 ± 0.04. Moreover, tumor volume, target motion three-dimensionally and ratio of tumor vertical diameter over tumor motion magnitude in cranio-caudal direction did not significantly influence the values of MI and proportion of Vunder. Conclusion The tool of ITV2M is recommended as a reliable method for generating ITVs from 4D CT data sets in liver cancer.

  11. The dosimetric impact of daily setup error on target volumes and surrounding normal tissue in the treatment of prostate cancer with intensity-modulated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Algan, Ozer, E-mail: oalgan@ouhsc.edu [Department of Radiation Oncology, Biostatistics and Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Jamgade, Ambarish; Ali, Imad; Christie, Alana; Thompson, J. Spencer; Thompson, David; Ahmad, Salahuddin; Herman, Terence [Department of Radiation Oncology, Biostatistics and Epidemiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2012-01-01

    The purpose of this study was to evaluate the impact of daily setup error and interfraction organ motion on the overall dosimetric radiation treatment plans. Twelve patients undergoing definitive intensity-modulated radiation therapy (IMRT) treatments for prostate cancer were evaluated in this institutional review board-approved study. Each patient had fiducial markers placed into the prostate gland before treatment planning computed tomography scan. IMRT plans were generated using the Eclipse treatment planning system. Each patient was treated to a dose of 8100 cGy given in 45 fractions. In this study, we retrospectively created a plan for each treatment day that had a shift available. To calculate the dose, the patient would have received under this plan, we mathematically 'negated' the shift by moving the isocenter in the exact opposite direction of the shift. The individualized daily plans were combined to generate an overall plan sum. The dose distributions from these plans were compared with the treatment plans that were used to treat the patients. Three-hundred ninety daily shifts were negated and their corresponding plans evaluated. The mean isocenter shift based on the location of the fiducial markers was 3.3 {+-} 6.5 mm to the right, 1.6 {+-} 5.1 mm posteriorly, and 1.0 {+-} 5.0 mm along the caudal direction. The mean D95 doses for the prostate gland when setup error was corrected and uncorrected were 8228 and 7844 cGy (p < 0.002), respectively, and for the planning target volume (PTV8100) was 8089 and 7303 cGy (p < 0.001), respectively. The mean V95 values when patient setup was corrected and uncorrected were 99.9% and 87.3%, respectively, for the PTV8100 volume (p < 0.0001). At an individual patient level, the difference in the D95 value for the prostate volume could be >1200 cGy and for the PTV8100 could approach almost 2000 cGy when comparing corrected against uncorrected plans. There was no statistically significant difference in the D35

  12. RTOG Sarcoma Radiation Oncologists Reach Consensus on Gross Tumor Volume and Clinical Target Volume on Computed Tomographic Images for Preoperative Radiotherapy of Primary Soft Tissue Sarcoma of Extremity in Radiation Therapy Oncology Group Studies

    Energy Technology Data Exchange (ETDEWEB)

    Wang Dian, E-mail: dwang@mcw.edu [Medical College of Wisconsin, Milwaukee, WI (United States); Bosch, Walter [Washington University, St. Louis, MO (United States); Roberge, David [McGill University, Montreal, Quebec (Canada); Finkelstein, Steven E. [Moffitt Cancer Center, Tampa, FL (United States); Petersen, Ivy; Haddock, Michael [Mayo Clinic, Rochester, MN (United States); Chen, Yen-Lin E.; Saito, Naoyuki G. [Roswell Park Cancer Institute, Buffalo, NY (United States); Kirsch, David G. [Duke University, Durham, NC (United States); Hitchcock, Ying J. [University of Utah, Salt Lake City, UT (United States); Wolfson, Aaron H. [University of Miami Miller School of Medicine, Miami, FL (United States); DeLaney, Thomas F. [Massachusetts General Hospital, Boston, MA (United States)

    2011-11-15

    Objective: To develop a Radiation Therapy Oncology Group (RTOG) atlas delineating gross tumor volume (GTV) and clinical target volume (CTV) to be used for preoperative radiotherapy of primary extremity soft tissue sarcoma (STS). Methods and Materials: A consensus meeting was held during the RTOG meeting in January 2010 to reach agreement about GTV and CTV delineation on computed tomography (CT) images for preoperative radiotherapy of high-grade large extremity STS. Data were presented to address the local extension of STS. Extensive discussion ensued to develop optimal criteria for GTV and CTV delineation on CT images. Results: A consensus was reached on appropriate CT-based GTV and CTV. The GTV is gross tumor defined by T1 contrast-enhanced magnetic resonance images. Fusion of magnetic resonance and images is recommended to delineate the GTV. The CTV for high-grade large STS typically includes the GTV plus 3-cm margins in the longitudinal directions. If this causes the field to extend beyond the compartment, the field can be shortened to include the end of a compartment. The radial margin from the lesion should be 1.5 cm, including any portion of the tumor not confined by an intact fascial barrier, bone, or skin surface. Conclusion: The consensus on GTV and CTV for preoperative radiotherapy of high-grade large extremity STS is available as web-based images and in a descriptive format through the RTOG. This is expected to improve target volume consistency and allow for rigorous evaluation of the benefits and risks of such treatment.

  13. High-resolution x-ray imaging of Kα volume radiation induced by high-intensity laser pulse interaction with a copper target

    Science.gov (United States)

    Galtier, E.; Moinard, A.; Khattak, F. Y.; Renner, O.; Robert, T.; Santos, J. J.; Beaucourt, C.; Angelo, P.; Tikhonchuk, V.; Rosmej, F. B.

    2012-10-01

    In a proof of principle experiment using the LULI 100-TW laser facility ELFIE, we have demonstrated high spectral and spatial resolution of Kα volume radiation induced by energetic electrons generated by irradiating solid Cu targets with visible (0.53 µm) 350 fs laser pulses. Employing an x-ray spectrometer equipped with the spherically bent crystal of quartz (502) and with an image plate, single shot Cu-Kα radiation was recorded in first-order reflection allowing for a geometrical mapping of the emission induced by hot electrons with a spatial resolution down to 30 µm. The simultaneously achieved high spectral resolution permitted the identification of asymmetries in the Kα1-group emission profile. Data from the shot in which a part of the laser beam was incident at grazing angle to the target surface show a signature of enhanced lateral transport of energetic electrons.

  14. Variation in the Gross Tumor Volume and Clinical Target Volume for Preoperative Radiotherapy of Primary Large High-Grade Soft Tissue Sarcoma of the Extremity Among RTOG Sarcoma Radiation Oncologists

    Energy Technology Data Exchange (ETDEWEB)

    Wang Dian, E-mail: dwang@mcw.edu [Medical College of Wisconsin, Milwaukee, WI (United States); Bosch, Walter [Washington University, St. Louis, MO (United States); Kirsch, David G. [Duke University, Durham, NC (United States); Al Lozi, Rawan; El Naqa, Issam [Washington University, St. Louis, MO (United States); Roberge, David [McGill University Health Centre, Montreal (Canada); Finkelstein, Steven E. [Moffitt Cancer Center, Tampa, FL (United States); Petersen, Ivy; Haddock, Michael [Mayo Clinic, Rochester, MN (United States); Chen, Yen-Lin E. [Massachusetts General Hospital, Boston, MA (United States); Saito, Naoyuki G. [Roswell Park Cancer Institute, Buffalo, NY (United States); Hitchcock, Ying J. [University of Utah, Salt Lake City, UT (United States); Wolfson, Aaron H. [University of Miami Miller School of Medicine, Miami, FL (United States); DeLaney, Thomas F. [Massachusetts General Hospital, Boston, MA (United States)

    2011-12-01

    Purpose: To evaluate variability in the definition of preoperative radiotherapy gross tumor volume (GTV) and clinical target volume (CTV) delineated by sarcoma radiation oncologists. Methods and Materials: Extremity sarcoma planning CT images along with the corresponding diagnostic MRI from two patients were distributed to 10 Radiation Therapy Oncology Group sarcoma radiation oncologists with instructions to define GTV and CTV using standardized guidelines. The CT data with contours were then returned for central analysis. Contours representing statistically corrected 95% (V95) and 100% (V100) agreement were computed for each structure. Results: For the GTV, the minimum, maximum, mean (SD) volumes (mL) were 674, 798, 752 {+-} 35 for the lower extremity case and 383, 543, 447 {+-} 46 for the upper extremity case. The volume (cc) of the union, V95 and V100 were 882, 761, and 752 for the lower, and 587, 461, and 455 for the upper extremity, respectively. The overall GTV agreement was judged to be almost perfect in both lower and upper extremity cases (kappa = 0.9 [p < 0.0001] and kappa = 0.86 [p < 0.0001]). For the CTV, the minimum, maximum, mean (SD) volumes (mL) were 1145, 1911, 1605 {+-} 211 for the lower extremity case and 637, 1246, 1006 {+-} 180 for the upper extremity case. The volume (cc) of the union, V95, and V100 were 2094, 1609, and 1593 for the lower, and 1533, 1020, and 965 for the upper extremity cases, respectively. The overall CTV agreement was judged to be almost perfect in the lower extremity case (kappa = 0.85 [p < 0.0001]) but only substantial in the upper extremity case (kappa = 0.77 [p < 0.0001]). Conclusions: Almost perfect agreement existed in the GTV of these two representative cases. Tshere was no significant disagreement in the CTV of the lower extremity, but variation in the CTV of upper extremity was seen, perhaps related to the positional differences between the planning CT and the diagnostic MRI.

  15. Evaluation of the cone beam CT for internal target volume localization in lung stereotactic radiotherapy in comparison with 4D MIP images

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lu; Chen, Xiaoming; Lin, Mu-Han; Lin, Teh; Fan, Jiajin; Jin, Lihui; Ma, Charlie M. [Department of Radiation Oncology, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, Pennsylvania 19111 (United States); Xue, Jun [Cancer Center of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)

    2013-11-15

    Purpose: To investigate whether the three-dimensional cone-beam CT (CBCT) is clinically equivalent to the four-dimensional computed tomography (4DCT) maximum intensity projection (MIP) reconstructed images for internal target volume (ITV) localization in image-guided lung stereotactic radiotherapy.Methods: A ball-shaped polystyrene phantom with built-in cube, sphere, and cone of known volumes was attached to a motor-driven platform, which simulates a sinusoidal movement with changeable motion amplitude and frequency. Target motion was simulated in the patient in a superior-inferior (S-I) direction with three motion periods and 2 cm peak-to-peak amplitudes. The Varian onboard Exact-Arms kV CBCT system and the GE LightSpeed four-slice CT integrated with the respiratory-position-management 4DCT scanner were used to scan the moving phantom. MIP images were generated from the 4DCT images. The clinical equivalence of the two sets of images was evaluated by comparing the extreme locations of the moving objects along the motion direction, the centroid position of the ITV, and the ITV volumes that were contoured automatically by Velocity or calculated with an imaging gradient method. The authors compared the ITV volumes determined by the above methods with those theoretically predicted by taking into account the physical object dimensions and the motion amplitudes. The extreme locations were determined by the gradient method along the S-I axis through the center of the object. The centroid positions were determined by autocenter functions. The effect of motion period on the volume sizes was also studied.Results: It was found that the extreme locations of the objects determined from the two image modalities agreed with each other satisfactorily. They were not affected by the motion period. The average difference between the two modalities in the extreme locations was 0.68% for the cube, 1.35% for the sphere, and 0.5% for the cone, respectively. The maximum difference in the

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

    NARCIS (Netherlands)

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

    2010-01-01

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2015-09-01

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

  20. Quantitative assessment of inter-observer variability in target volume delineation on stereotactic radiotherapy treatment for pituitary adenoma and meningioma near optic tract

    International Nuclear Information System (INIS)

    To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise. We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma) including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans), were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan. The median planning target volume (PTV) and the ratio of the largest to the smallest contoured volume were 9.22 cm3 (range, 7.17 - 14.3 cm3) and 1.99 for pituitary adenoma, and 6.86 cm3 (range 6.05 - 14.6 cm3) and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm3 for group 1 with a margin of 1 -2 mm around the CTV (n = 3) and 9.28 ± 1.8 cm3(p = 0.51) for group 2 with no margin (n = 7) in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm3) than group 2 (6.91 ± 0.7 cm3, p = 0.03). All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation). However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan) in pituitary adenoma and 24.84 Gy (131% of the default plan) in meningioma to the optic nerve in the contours from different contouring. Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract

  1. Quantitative assessment of inter-observer variability in target volume delineation on stereotactic radiotherapy treatment for pituitary adenoma and meningioma near optic tract

    Directory of Open Access Journals (Sweden)

    Aibe Norihiro

    2011-01-01

    Full Text Available Abstract Background To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise. Methods We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans, were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan. Results The median planning target volume (PTV and the ratio of the largest to the smallest contoured volume were 9.22 cm3 (range, 7.17 - 14.3 cm3 and 1.99 for pituitary adenoma, and 6.86 cm3 (range 6.05 - 14.6 cm3 and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm3 for group 1 with a margin of 1 -2 mm around the CTV (n = 3 and 9.28 ± 1.8 cm3(p = 0.51 for group 2 with no margin (n = 7 in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm3 than group 2 (6.91 ± 0.7 cm3, p = 0.03. All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation. However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan in pituitary adenoma and 24.84 Gy (131% of the default plan in meningioma to the optic nerve in the contours from different contouring. Conclusion Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract.

  2. Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, J.; Galvis-Alonso, O.Y. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Faculdade de Medicina. Dept. de Biologia Molecular], e-mail: mejia_famerp@yahoo.com.br; Braga, J. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Div. de Astrofisica; Correa, R. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Ciencia Espacial e Atmosferica; Leite, J.P. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Neurologia, Psiquiatria e Psicologia Medica; Simoes, M.V. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Clinica Medica

    2009-08-15

    Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multi pinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target's radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals. (author)

  3. Magnetic Resonance Imaging-Based Target Volume Delineation in Radiation Therapy Treatment Planning for Brain Tumors Using Localized Region-Based Active Contour

    International Nuclear Information System (INIS)

    Purpose: To evaluate the clinical application of a robust semiautomatic image segmentation method to determine the brain target volumes in radiation therapy treatment planning. Methods and Materials: A local robust region-based algorithm was used on MRI brain images to study the clinical target volume (CTV) of several patients. First, 3 oncologists delineated CTVs of 10 patients manually, and the process time for each patient was calculated. The averages of the oncologists’ contours were evaluated and considered as reference contours. Then, to determine the CTV through the semiautomatic method, a fourth oncologist who was blind to all manual contours selected 4-8 points around the edema and defined the initial contour. The time to obtain the final contour was calculated again for each patient. Manual and semiautomatic segmentation were compared using 3 different metric criteria: Dice coefficient, Hausdorff distance, and mean absolute distance. A comparison also was performed between volumes obtained from semiautomatic and manual methods. Results: Manual delineation processing time of tumors for each patient was dependent on its size and complexity and had a mean (±SD) of 12.33 ± 2.47 minutes, whereas it was 3.254 ± 1.7507 minutes for the semiautomatic method. Means of Dice coefficient, Hausdorff distance, and mean absolute distance between manual contours were 0.84 ± 0.02, 2.05 ± 0.66 cm, and 0.78 ± 0.15 cm, and they were 0.82 ± 0.03, 1.91 ± 0.65 cm, and 0.7 ± 0.22 cm between manual and semiautomatic contours, respectively. Moreover, the mean volume ratio (=semiautomatic/manual) calculated for all samples was 0.87. Conclusions: Given the deformability of this method, the results showed reasonable accuracy and similarity to the results of manual contouring by the oncologists. This study shows that the localized region-based algorithms can have great ability in determining the CTV and can be appropriate alternatives for manual approaches in brain cancer

  4. Comparison and Consensus Guidelines for Delineation of Clinical Target Volume for CT- and MR-Based Brachytherapy in Locally Advanced Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, Akila N., E-mail: aviswanathan@lroc.harvard.edu [Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Erickson, Beth [Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Gaffney, David K. [University of Utah Huntsman Cancer Hospital, Salt Lake City, Utah (United States); Beriwal, Sushil [University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania (United States); Bhatia, Sudershan K. [University of Iowa, Iowa City, Iowa (United States); Lee Burnett, Omer [University of Alabama, Birmingham, Alabama (United States); D' Souza, David P.; Patil, Nikhilesh [London Health Sciences Centre and Western University, London, Ontario (Canada); Haddock, Michael G. [Mayo Medical Center, Rochester, Minnesota (United States); Jhingran, Anuja [University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Jones, Ellen L. [University of North Carolina, Chapel Hill, North Carolina (United States); Kunos, Charles A. [Case Western Reserve University, Cleveland, Ohio (United States); Lee, Larissa J. [Brigham and Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Lin, Lilie L. [University of Pennsylvania, Philadelphia, Pennsylvania (United States); Mayr, Nina A. [University of Washington, Seattle, Washington (United States); Petersen, Ivy [Mayo Medical Center, Rochester, Minnesota (United States); Petric, Primoz [Division of Radiotherapy, Institute of Oncology Ljubljana, Ljubljana (Slovenia); Department of Radiation Oncology, National Center for Cancer Care and Research, Doha (Qatar); Portelance, Lorraine [University of Miami Miller School of Medicine, Miami, Florida (United States); Small, William [Loyola University Strich School of Medicine, Chicago, Illinois (United States); Strauss, Jonathan B. [The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois (United States); and others

    2014-10-01

    Objective: To create and compare consensus clinical target volume (CTV) contours for computed tomography (CT) and 3-Tesla (3-T) magnetic resonance (MR) image-based cervical-cancer brachytherapy. Methods and Materials: Twenty-three experts in gynecologic radiation oncology contoured the same 3 cervical cancer brachytherapy cases: 1 stage IIB near-complete response (CR) case with a tandem and ovoid, 1 stage IIB partial response (PR) case with tandem and ovoid with needles, and 1 stage IB2 CR case with a tandem and ring applicator. The CT contours were completed before the MRI contours. These were analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with κ statistics as a measure of agreement between participants. The conformity index was calculated for each of the 6 data sets. Dice coefficients were generated to compare the CT and MR contours of the same case. Results: For all 3 cases, the mean tumor volume was smaller on MR than on CT (P<.001). The κ and conformity index estimates were slightly higher for CT, indicating a higher level of agreement on CT. The Dice coefficients were 89% for the stage IB2 case with a CR, 74% for the stage IIB case with a PR, and 57% for the stage IIB case with a CR. Conclusion: In a comparison of MR-contoured with CT-contoured CTV volumes, the higher level of agreement on CT may be due to the more distinct contrast medium visible on the images at the time of brachytherapy. MR at the time of brachytherapy may be of greatest benefit in patients with large tumors with parametrial extension that have a partial or complete response to external beam. On the basis of these results, a 95% consensus volume was generated for CT and for MR. Online contouring atlases are available for instruction at (http://www.nrgoncology.org/Resources/ContouringAtlases/GYNCervicalBrachytherapy.aspx)

  5. Comparison and Consensus Guidelines for Delineation of Clinical Target Volume for CT- and MR-Based Brachytherapy in Locally Advanced Cervical Cancer

    International Nuclear Information System (INIS)

    Objective: To create and compare consensus clinical target volume (CTV) contours for computed tomography (CT) and 3-Tesla (3-T) magnetic resonance (MR) image-based cervical-cancer brachytherapy. Methods and Materials: Twenty-three experts in gynecologic radiation oncology contoured the same 3 cervical cancer brachytherapy cases: 1 stage IIB near-complete response (CR) case with a tandem and ovoid, 1 stage IIB partial response (PR) case with tandem and ovoid with needles, and 1 stage IB2 CR case with a tandem and ring applicator. The CT contours were completed before the MRI contours. These were analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with κ statistics as a measure of agreement between participants. The conformity index was calculated for each of the 6 data sets. Dice coefficients were generated to compare the CT and MR contours of the same case. Results: For all 3 cases, the mean tumor volume was smaller on MR than on CT (P<.001). The κ and conformity index estimates were slightly higher for CT, indicating a higher level of agreement on CT. The Dice coefficients were 89% for the stage IB2 case with a CR, 74% for the stage IIB case with a PR, and 57% for the stage IIB case with a CR. Conclusion: In a comparison of MR-contoured with CT-contoured CTV volumes, the higher level of agreement on CT may be due to the more distinct contrast medium visible on the images at the time of brachytherapy. MR at the time of brachytherapy may be of greatest benefit in patients with large tumors with parametrial extension that have a partial or complete response to external beam. On the basis of these results, a 95% consensus volume was generated for CT and for MR. Online contouring atlases are available for instruction at (http://www.nrgoncology.org/Resources/ContouringAtlases/GYNCervicalBrachytherapy.aspx)

  6. Beam-specific planning target volumes incorporating 4D CT for pencil beam scanning proton therapy of thoracic tumors.

    Science.gov (United States)

    Lin, Liyong; Kang, Minglei; Huang, Sheng; Mayer, Rulon; Thomas, Andrew; Solberg, Timothy D; McDonough, James E; Simone, Charles B

    2015-11-08

    The purpose of this study is to determine whether organ sparing and target coverage can be simultaneously maintained for pencil beam scanning (PBS) proton therapy treatment of thoracic tumors in the presence of motion, stopping power uncertainties, and patient setup variations. Ten consecutive patients that were previously treated with proton therapy to 66.6/1.8 Gy (RBE) using double scattering (DS) were replanned with PBS. Minimum and maximum intensity images from 4D CT were used to introduce flexible smearing in the determination of the beam specific PTV (BSPTV). Datasets from eight 4D CT phases, using ± 3% uncertainty in stopping power and ± 3 mm uncertainty in patient setup in each direction, were used to create 8 × 12 × 10 = 960 PBS plans for the evaluation of 10 patients. Plans were normalized to provide identical coverage between DS and PBS. The average lung V20, V5, and mean doses were reduced from 29.0%, 35.0%, and 16.4 Gy with DS to 24.6%, 30.6%, and 14.1 Gy with PBS, respectively. The average heart V30 and V45 were reduced from 10.4% and 7.5% in DS to 8.1% and 5.4% for PBS, respectively. Furthermore, the maximum spinal cord, esophagus, and heart doses were decreased from 37.1 Gy, 71.7 Gy, and 69.2 Gy with DS to 31.3 Gy, 67.9 Gy, and 64.6 Gy with PBS. The conformity index (CI), homogeneity index (HI), and global maximal dose were improved from 3.2, 0.08, 77.4 Gy with DS to 2.8, 0.04, and 72.1 Gy with PBS. All differences are statistically significant, with p-values <0.05, with the exception of the heart V45 (p = 0.146). PBS with BSPTV achieves better organ sparing and improves target coverage using a repainting method for the treatment of thoracic tumors. Incorporating motion-related uncertainties is essential.

  7. Beam specific planning target volumes incorporating 4DCT for pencil beam scanning proton therapy of thoracic tumors

    CERN Document Server

    Lin, Liyong; Huang, Sheng; Mayer, Rulon; Thomas, Andrew; Solberg, Timothy D; McDonough, James E; Simone, Charles B

    2015-01-01

    The purpose of this study is to determine whether organ sparing and target coverage can be simultaneously maintained for pencil beam scanning (PBS) proton therapy treatment of thoracic tumors in the presence of motion, stopping power uncertainties and patient setup variations. Ten consecutive patients that were previously treated with proton therapy to 66.6/1.8 Gy (RBE) using double scattering (DS) were replanned with PBS. Minimum and maximum intensity images from 4DCT were used to introduce flexible smearing in the determination of the beam specific PTV (BSPTV). Datasets from eight 4DCT phases, using +-3% uncertainty in stopping power, and +-3 mm uncertainty in patient setup in each direction were used to create 8X12X10=960 PBS plans for the evaluation of ten patients. Plans were normalized to provide identical coverage between DS and PBS. The average lung V20, V5, and mean doses were reduced from 29.0%, 35.0%, and 16.4 Gy with DS to 24.6%, 30.6%, and 14.1 Gy with PBS, respectively. The average heart V30 and...

  8. Treatment of Non-Small Cell Lung Cancer (NSCLC) Using CT in Combination with a PET Examination to Minimize the Clinical Target Volume of the Mediastinum

    Institute of Scientific and Technical Information of China (English)

    Yusheng Shi; Xiaogang Deng; Longhua Chen

    2007-01-01

    OBJECTIVE To decrease radiation injury of the esophagus and lungs by utilizing a CT scan in combination with PET tumor imaging in order to minimize the clinical target area of locally advanced non-small cell lung cancer, without preventive radiation on the lymphatic drainage area. METHODS Of 76 patients with locally advanced non-small cell lung cancer (NSCLC), 32 received a PET examination before radiotherapy. Preventive radiation was not conducted in the mediastinum area without lymphatic metastasis, which was confirmed by CT and PET. For the other 44 patients, preventive radiation was performed in the lymphatic drainage area. PET examinations showed that the clinical target volume of the patients was decreased on average to about one third. The radiation therapy for patients of the two groups was the same, I.e. The dose for accelerated fractionated irradiation was 3 Gy/time and 5 time/week. The preventive dose was 42 to 45 Gy/time, 14 to 15 time/week, with 3-week treatment, and the therapeutic dose was 60 to 63 Gy/time, 20 to 21 time/week, with a period of 4 to 5 weeks.RESULTS The rate of missed lymph nodes beyond the irradiation field was 6.3% and 4.5% respectively in the group with and without PET examination (P = 0.831). The incidence of acute radioactive esophagitis was 15.6 % and 45.5% in the two groups respectively (P = 0.006). The incidence of acute radiation pneumonia and long-term pulmonary fibrosis in the two groups was 6.3% and 9.1%, and 68.8% and 75.0%, respectively (P = 0.982 and P = 0.547).CONCLUSION The recurrence rate in the lymph nodes beyond the target area was not increased after minimizing the clinical target volume (CTV), whereas radioactive injury to the lungs and esophageal injury was reduced, and especially with a significant decrease in the rate of acute radioactive esophagitis. The method of CT in combination with PET for minimizing the mediastinal CTV is superior to the conventional preventive radiation of the mediastinum.

  9. PET/CT imaging for target volume delineation in curative intent radiotherapy of non-small cell lung cancer: IAEA consensus report 2014

    International Nuclear Information System (INIS)

    This document describes best practice and evidence based recommendations for the use of FDG-PET/CT for the purposes of radiotherapy target volume delineation (TVD) for curative intent treatment of non-small cell lung cancer (NSCLC). These recommendations have been written by an expert advisory group, convened by the International Atomic Energy Agency (IAEA) to facilitate a Coordinated Research Project (CRP) aiming to improve the applications of PET based radiation treatment planning (RTP) in low and middle income countries. These guidelines can be applied in routine clinical practice of radiotherapy TVD, for NSCLC patients treated with concurrent chemoradiation or radiotherapy alone, where FDG is used, and where a calibrated PET camera system equipped for RTP patient positioning is available. Recommendations are provided for PET and CT image visualization and interpretation, and for tumor delineation using planning CT with and without breathing motion compensation

  10. A Prospective Pathologic Study to Define the Clinical Target Volume for Partial Breast Radiation Therapy in Women With Early Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Brandon T., E-mail: Brandon.Nguyen@act.gov.au [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Canberra Hospital, Radiation Oncology Department, Garran, ACT (Australia); Deb, Siddhartha [Department of Anatomical Pathology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Victorian Cancer Biobank, Cancer Council of Victoria, Carlton, Victoria (Australia); Fox, Stephen [Department of Anatomical Pathology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Hill, Prudence [Department of Anatomical Pathology, St. Vincent' s Hospital Melbourne, Fitzroy, Victoria (Australia); Collins, Marnie [Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Chua, Boon H. [Department of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); University of Melbourne, Parkville, Victoria (Australia)

    2012-12-01

    Purpose: To determine an appropriate clinical target volume for partial breast radiation therapy (PBRT) based on the spatial distribution of residual invasive and in situ carcinoma after wide local excision (WLE) for early breast cancer or ductal carcinoma in situ (DCIS). Methods and Materials: We performed a prospective pathologic study of women potentially eligible for PBRT who had re-excision and/or completion mastectomy after WLE for early breast cancer or DCIS. A pathologic assessment protocol was used to determine the maximum radial extension (MRE) of residual carcinoma from the margin of the initial surgical cavity. Women were stratified by the closest initial radial margin width: negative (>1 mm), close (>0 mm and {<=}1 mm), or involved. Results: The study population was composed of 133 women with a median age of 59 years (range, 27-82 years) and the following stage groups: 0 (13.5%), I (40.6%), II (38.3%), and III (7.5%). The histologic subtypes of the primary tumor were invasive ductal carcinoma (74.4%), invasive lobular carcinoma (12.0%), and DCIS alone (13.5%). Residual carcinoma was present in the re-excision and completion mastectomy specimens in 55.4%, 14.3%, and 7.2% of women with an involved, close, and negative margin, respectively. In the 77 women with a noninvolved radial margin, the MRE of residual disease, if present, was {<=}10 mm in 97.4% (95% confidence interval 91.6-99.5) of cases. Larger MRE measurements were significantly associated with an involved margin (P<.001), tumor size >30 mm (P=.03), premenopausal status (P=.03), and negative progesterone receptor status (P=.05). Conclusions: A clinical target volume margin of 10 mm would encompass microscopic residual disease in >90% of women potentially eligible for PBRT after WLE with noninvolved resection margins.

  11. A Prospective Evaluation of Staging and Target Volume Definition of Lymph Nodes by 18FDG PET/CT in Patients With Squamous Cell Carcinoma of Thoracic Esophagus

    International Nuclear Information System (INIS)

    Purpose: To determine an optimal standardized uptake value (SUV) threshold for detecting lymph node (LN) metastases in esophageal cancer using 18F-Fluorodeoxyglucose positron emission tomography/computer tomography (18FDG PET/CT) and to define the resulting nodal target volume, using histopathology as a “gold standard.” Methods: Sixteen patients with esophageal squamous cell carcinoma who underwent radical esophagectomy and three-field LN dissection after 18FDG PET/CT and CT scans were enrolled into this study. Locations of LN groups were recorded according to a uniform LN map. Diagnostic performance of different SUV thresholds was assessed by receiver operating characteristic analysis. The optimal cutoff SUV was determined by plotting the false-negative rate (FNR) and false-positive rate (FPR), the sum of both error rates (FNR+FPR), and accuracy against a hypothetical SUV threshold. For each patient, nodal gross tumor volumes (GTVNs) were generated with CT alone (GTVNCT), PET/CT (GTVNPET), and pathologic data (GTVNpath). GTVNCT or GTVNPET was compared with GTVNpath by means of a conformity index (CI), which is the intersection of the two GTVNs divided by the sum of them minus the intersection, e.g., CICT and path = GTVNCT and path/(GTVNCT+ GTVNpath – GTVNCT and path). Results: LN metastases occurred in 21 LN groups among the 144 specimens taken from the 16 patients. The area under the receiver operating characteristic curve was 0.9017 ± 0.0410. The plot of error rates showed a minimum of FNR+FPR for an SUV of 2.36, at which the sensitivity, specificity, and accuracy were 76.19%, 95.93%, and 93.06%, respectively, whereas those of CT were 33.33%, 94.31%, and 85.42% (p values: 0.0117, 0.7539, and 0.0266). Mean GTVNCT, GTVNPET, and GTVNpath were 1.52 ± 2.38, 2.82 ± 4.51, and 2.68 ± 4.16cm3, respectively. Mean CICT and path and CIPET and path were 0.31 and 0.65 (p value = 0.0352). Conclusions: Diagnostic superiority of PET/CT at an SUV threshold of 2.36 over

  12. 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...

  13. Comparison of target volumes in radiotherapy defined on scanner and on PET-T.D.M. with {sup 18}F-F.D.G. in the frame of head and neck cancers; Comparaison des volumes cibles en radiotherapie definis sur scanner et sur TEP-TDM au 18F FDG dans le cadre des cancers de la tete et du cou

    Energy Technology Data Exchange (ETDEWEB)

    Henriques De Figueiredo, B.; Barret, O.; Allard, M.; Fernandez, P. [Service de medecine nucleaire, CHU de Pellegrin, Bordeaux, (France); Demeaux, H.; Maire, J.P.; Lagarde, P. [service de radiotherapie, hopital Saint-Andre, Bordeaux, (France); Kantor, G.; Richau, P. [departement de radiotherapie, institut Bergonie, Bordeaux, (France); De Mones Del Pujol, E. [service d' ORL, hopital Pellegrin, Bordeaux, (France)

    2009-05-15

    The objective is to study in a prospective way, in the frame of head and neck cancers, the impact of the positron computed tomography with {sup 18}F fluorodeoxyglucose (PET-F.D.G.) on the limitation of target volumes in radiotherapy. In conclusions, the gross tumor volume (G.T.V.) defined on PET is smaller than this one defined on scanner, that could be interesting in radiotherapy, in the perspective of a dose escalation. In addition, areas of discordance exist between the clinical target volumes (C.T.V.70 and C.T.V.50) defined on PET and on scanner. These discordances, synonyms of under or over estimation of target volumes, could have important clinical consequences in term of local control and toxicity. (N.C.)

  14. Feasibility of omitting clinical target volume for limited-disease small cell lung cancer treated with chemotherapy and intensity-modulated radiotherapy

    International Nuclear Information System (INIS)

    To analyze the feasibility of omitting clinical target volume (CTV) for limited small cell lung cancer treated with chemotherapy and intensity modulated radiotherapy. 89 patients were treated from January 1, 2008 to August 31, 2011, 54 cases were irradiated with target volume without CTV, and 35 cases were irradiated with CTV. Both arms were irradiated post chemotherapy tumor extent and omitted elective nodal irradiation; dose prescription was 95% PTV56-63 Gy/28-35 F/5.6-7 weeks. In the arm without CTV and arm with CTV, the local relapse rates were 16.7% and 17.1% (p = 0.586) respectively. In the arm without CTV, of the 9 patients with local relapse, 6 recurred in-field, 2 recurred in margin, 1 recurred out of field. In the arm with CTV, of the 6 patients with local relapse, 4 recurred in-field, 1 recurred in margin, 1 recurred out of field. The distant metastases rates were 42.6% and 51.4% (p = 0.274) respectively. Grade 3-4 hematological toxicity and radiation esophagitis had no statistically significant, but grade 3-4 radiation pneumonia was observed in only 7.4% in the arm without CTV, compared 22.9% in the arm with CTV (p = 0.040). The median survival in the arm without CTV had not reached, compared with 38 months in the with CTV arm. The l- years, 2- years, 3- years survival rates of the arm without CTV and the arm with CTV were 81.0%, 66.2%, 61.5% and 88.6%, 61.7%, 56.6% (p = 0.517). The multivariate analysis indicated that the distant metastases (p = 0.000) and PCI factor (p = 0.004) were significantly related to overall survival. Target delineation omitting CTV for limited-disease small cell lung cancer received IMRT was feasible. The distant metastases and PCI factor were significantly related to overall survival

  15. Image-Guided Radiation Therapy for Muscle-Invasive Carcinoma of the Urinary Bladder with Cone Beam CT Scan: Use of Individualized Internal Target Volumes for a Single Patient

    OpenAIRE

    Saini, Gagan; Aggarwal, Anchal; Srivastava, Roopam; Sharma, Pramod K.; Garg, Madhur; Nangia, Sapna; Chomal, Manish

    2012-01-01

    Introduction While planning radiation therapy (RT) for a carcinoma of the urinary bladder (CaUB), the intra-fractional variation of the urinary bladder (UB) volume due to filling-up needs to be accounted for. This internal target volume (ITV) is obtained by adding internal margins (IM) to the contoured bladder. This study was planned to propose a method of acquiring individualized ITVs for each patient and to verify their reproducibility. Methods One patient with CaUB underwent simulation wit...

  16. Potential impacts of OCS oil and gas activities on fisheries. Volume 1. Annotated bibliography and database descriptions for target species distribution and abundance studies. Section 1, Part 1. Final report. [Outer Continental Shelf

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the volume is to present an annotated bibliography of unpublished and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes descriptions of databases that contain information related to target species' distribution and abundance. An index is provided at the end of each section to help the reader locate studies or databases related to a particular species.

  17. Potential impacts of OCS oil and gas activities on fisheries. Volume 1. Annotated bibliography and data-base descriptions for target-species distribution and abundance studies. Section 2. Final report. [Outer Continental Shelf

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the volume is to present an annotated bibliography of unpublished and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes description of databases that contain information related to target species' distribution and abundance. An index is provided at the end of each section to help the reader locate studies or databases related to a particular species.

  18. Potential impacts of OCS oil and gas activities on fisheries. Volume 1. Annotated bibliography and database descriptions for target-species distribution and abundance studies. Section 1, Part 2. Final report. [Outer Continental Shelf

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the volume is to present an annotated bibliography of unpublished and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes descriptions of databases that contain information related to target species' distribution and abundance. An index is provided at the end of each section to help the reader locate studies or databases related to a particular species.

  19. Target volume definition in high-risk prostate cancer patients using sentinel node SPECT/CT and 18 F-choline PET/CT

    Directory of Open Access Journals (Sweden)

    Vees Hansjörg

    2012-08-01

    Full Text Available Abstract Background To assess the influence of sentinel lymph nodes (SNs SPECT/CT and 18 F-choline (18 F-FCH PET/CT in radiotherapy (RT treatment planning for prostate cancer patients with a high-risk for lymph node (LN involvement. Methods Twenty high-risk prostate cancer patients underwent a pelvic SPECT acquisition following a transrectal ultrasound guided injection of 99mTc-Nanocoll into the prostate. In all patients but one an 18 F-FCH PET/CT for RT treatment planning was performed. SPECT studies were coregistered with the respective abdominal CTs. Pelvic SNs localized on SPECT/CT and LN metastases detected by 18 F-FCH PET/CT were compared to standard pelvic clinical target volumes (CTV. Results A total of 104 pelvic SNs were identified on SPECT/CT (mean 5.2 SNs/patient; range 1–10. Twenty-seven SNs were located outside the standard pelvic CTV, 17 in the proximal common iliac and retroperitoneal regions above S1, 9 in the pararectal fat and 1 in the inguinal region. SPECT/CT succeeded to optimize the definition of the CTV and treatment plans in 6/20 patients due to the presence of pararectal SNs located outside the standard treatment volume. 18 F-FCH PET/CT identified abnormal tracer uptake in the iliac LN region in 2/19 patients. These abnormal LNs were negative on SPECT/CT suggesting a potential blockade of lymphatic drainage by metastatic LNs with a high tumour burden. Conclusions Multimodality imaging which combines SPECT/CT prostate lymphoscintigraphy and 18 F-FCH PET/CT identified SNs outside standard pelvic CTVs or highly suspicious pelvic LNs in 40% of high-risk prostate cancer patients, highlighting the potential impact of this approach in RT treatment planning.

  20. Target volume definition in high-risk prostate cancer patients using sentinel node SPECT/CT and 18 F-choline PET/CT

    International Nuclear Information System (INIS)

    To assess the influence of sentinel lymph nodes (SNs) SPECT/CT and 18 F-choline (18 F-FCH) PET/CT in radiotherapy (RT) treatment planning for prostate cancer patients with a high-risk for lymph node (LN) involvement. Twenty high-risk prostate cancer patients underwent a pelvic SPECT acquisition following a transrectal ultrasound guided injection of 99mTc-Nanocoll into the prostate. In all patients but one an 18 F-FCH PET/CT for RT treatment planning was performed. SPECT studies were coregistered with the respective abdominal CTs. Pelvic SNs localized on SPECT/CT and LN metastases detected by 18 F-FCH PET/CT were compared to standard pelvic clinical target volumes (CTV). A total of 104 pelvic SNs were identified on SPECT/CT (mean 5.2 SNs/patient; range 1–10). Twenty-seven SNs were located outside the standard pelvic CTV, 17 in the proximal common iliac and retroperitoneal regions above S1, 9 in the pararectal fat and 1 in the inguinal region. SPECT/CT succeeded to optimize the definition of the CTV and treatment plans in 6/20 patients due to the presence of pararectal SNs located outside the standard treatment volume. 18 F-FCH PET/CT identified abnormal tracer uptake in the iliac LN region in 2/19 patients. These abnormal LNs were negative on SPECT/CT suggesting a potential blockade of lymphatic drainage by metastatic LNs with a high tumour burden. Multimodality imaging which combines SPECT/CT prostate lymphoscintigraphy and 18 F-FCH PET/CT identified SNs outside standard pelvic CTVs or highly suspicious pelvic LNs in 40% of high-risk prostate cancer patients, highlighting the potential impact of this approach in RT treatment planning

  1. Suspect screening and target quantification of multi-class pharmaceuticals in surface water based on large-volume injection liquid chromatography and time-of-flight mass spectrometry.

    Science.gov (United States)

    Vergeynst, Leendert; Van Langenhove, Herman; Joos, Pieter; Demeestere, Kristof

    2014-04-01

    The ever-growing number of emerging micropollutants such as pharmaceuticals requests rapid and sensitive full-spectrum analytical techniques. Time-of-flight high-resolution mass spectrometry (TOF-HRMS) is a promising alternative for the state-of-the-art tandem mass spectrometry instruments because of its ability to simultaneously screen for a virtually unlimited number of suspect analytes and to perform target quantification. The challenge for such suspect screening is to develop a strategy, which minimizes the false-negative rate without restraining numerous false-positives. At the same time, omitting laborious sample enrichment through large-volume injection ultra-performance liquid chromatography (LVI-UPLC) avoids selective preconcentration. A suspect screening strategy was developed using LVI-UPLC-TOF-MS aiming the detection of 69 multi-class pharmaceuticals in surface water without the a priori availability of analytical standards. As a novel approach, the screening takes into account the signal-intensity-dependent accurate mass error of TOF-MS, hereby restraining 95 % of the measured suspect pharmaceuticals present in surface water. Application on five Belgian river water samples showed the potential of the suspect screening approach, as exemplified by a false-positive rate not higher than 15 % and given that 30 out of 37 restrained suspect compounds were confirmed by the retention time of analytical standards. Subsequently, this paper discusses the validation and applicability of the LVI-UPLC full-spectrum HRMS method for target quantification of the 69 pharmaceuticals in surface water. Analysis of five Belgian river water samples revealed the occurrence of 17 pharmaceuticals in a concentration range of 17 ng L(-1) up to 3.1 μg L(-1). PMID:24633561

  2. Radiation Therapy Oncology Group Consensus Panel Guidelines for the Delineation of the Clinical Target Volume in the Postoperative Treatment of Pancreatic Head Cancer

    International Nuclear Information System (INIS)

    Purpose: To develop contouring guidelines to be used in the Radiation Therapy Oncology Group protocol 0848, a Phase III randomized trial evaluating the benefit of adjuvant chemoradiation in patients with resected head of pancreas cancer. Methods and Materials: A consensus committee of six radiation oncologists with expertise in gastrointestinal radiotherapy developed stepwise contouring guidelines and an atlas for the delineation of the clinical target volume (CTV) in the postoperative treatment of pancreas cancer, based on identifiable regions of interest and margin expansions. Areas at risk for subclinical disease to be included in the CTV were defined, including nodal regions, anastomoses, and the preoperative primary tumor location. Regions of interest that could be reproducibly contoured on postoperative imaging after a pancreaticoduodenectomy were identified. Standardized expansion margins to encompass areas at risk were developed after multiple iterations to determine the optimal margin expansions. Results: New contouring recommendations based on CT anatomy were established. Written guidelines for the delineation of the postoperative CTV and normal tissues, as well as a Web-based atlas, were developed. Conclusions: The postoperative abdomen has been a difficult area for effective radiotherapy. These new guidelines will help physicians create fields that better encompass areas at risk and minimize dose to normal tissues.

  3. Skin Cancer of the Head and Neck With Perineural Invasion: Defining the Clinical Target Volumes Based on the Pattern of Failure

    International Nuclear Information System (INIS)

    Purpose: To analyze patterns of failure in patients with head-and-neck cutaneous squamous cell carcinoma (HNCSCC) and clinical/radiologic evidence of perineural invasion (CPNI), in order to define neural clinical target volume (CTV) for treatment planning. Methods and Materials: Patients treated with three-dimensional (3D) conformal or intensity-modulated radiotherapy (IMRT) for HNCSCC with CPNI were included in the study. A retrospective review of the clinical charts, radiotherapy (RT) plans and radiologic studies has been conducted. Results: Eleven consecutive patients with HNCSCCs with CPNI were treated from 2000 through 2007. Most patients underwent multiple surgical procedures and RT courses. The most prevalent failure pattern was along cranial nerves (CNs), and multiple CNs were ultimately involved in the majority of cases. In all cases the involved CNs at recurrence were the main nerves innervating the primary tumor sites, as well as their major communicating nerves. We have found several distinct patterns of disease spread along specific CNs depending on the skin regions harboring the primary tumors, including multiple branches of CN V and VII. These patterns and the pertinent anatomy are detailed in the this article. Conclusions: Predictable disease spread patterns along cranial nerves supplying the primary tumor sites were found in this study. Awareness of these patterns, as well as knowledge of the relevant cranial nerve anatomy, should be the basis for CTV definition and delineation for RT treatment planning.

  4. Radiation Therapy Oncology Group Consensus Panel Guidelines for the Delineation of the Clinical Target Volume in the Postoperative Treatment of Pancreatic Head Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, Karyn A., E-mail: goodmank@mskcc.org [Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Regine, William F. [University of Maryland School of Medicine, Baltimore, Maryland (United States); Dawson, Laura A. [Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Ben-Josef, Edgar [University of Michigan Medical School, Ann Arbor, Michigan (United States); Haustermans, Karin [University Hospital Leuven, Leuven (Belgium); Bosch, Walter R. [Image-Guided Therapy QA Center, Washington University, St. Louis, Missouri (United States); Turian, Julius; Abrams, Ross A. [Rush University Medical College, Chicago, Illinois (United States)

    2012-07-01

    Purpose: To develop contouring guidelines to be used in the Radiation Therapy Oncology Group protocol 0848, a Phase III randomized trial evaluating the benefit of adjuvant chemoradiation in patients with resected head of pancreas cancer. Methods and Materials: A consensus committee of six radiation oncologists with expertise in gastrointestinal radiotherapy developed stepwise contouring guidelines and an atlas for the delineation of the clinical target volume (CTV) in the postoperative treatment of pancreas cancer, based on identifiable regions of interest and margin expansions. Areas at risk for subclinical disease to be included in the CTV were defined, including nodal regions, anastomoses, and the preoperative primary tumor location. Regions of interest that could be reproducibly contoured on postoperative imaging after a pancreaticoduodenectomy were identified. Standardized expansion margins to encompass areas at risk were developed after multiple iterations to determine the optimal margin expansions. Results: New contouring recommendations based on CT anatomy were established. Written guidelines for the delineation of the postoperative CTV and normal tissues, as well as a Web-based atlas, were developed. Conclusions: The postoperative abdomen has been a difficult area for effective radiotherapy. These new guidelines will help physicians create fields that better encompass areas at risk and minimize dose to normal tissues.

  5. Prospective evaluation of microscopic extension using whole-mount preparation in patients with hepatocellular carcinoma: Definition of clinical target volume for radiotherapy

    International Nuclear Information System (INIS)

    To define the clinical target volume (CTV) for radiotherapy in patients with hepatocellular carcinoma (HCC). A prospective study was conducted to histologically evaluate the presence and the distance of microscopic extension (ME) for resected HCC on the basis of examination of whole-mount preparations of carcinoma tissue sections. A total of 380 whole-mount slides prepared from tumor samples of 76 patients with HCC were examined. Patients with elevated pretreatment AFP levels exhibited higher risk of ME as compared to those with normal pretreatment AFP levels (93.9% vs. 69.8%, P < 0.01). ME positivity was 16.7% for Grade 1, 79.1% for Grade 2, and 96.3% for Grade 3 tumors (P < 0.01). The mean distance of ME was 0.0 ± 0.1 mm (range 0-0.2 mm) for Grade 1, 0.9 ± 0.9 mm (range 0-4.5 mm) for Grade 2, and 1.9 ± 1.9 mm (range 0-8.0 mm) for Grade 3 tumors (P < 0.01). The CTV margins for tumor Grades 1, 2, and 3 HCC, are recommended to be 0.2 mm, 4.5 mm, and 8.0 mm beyond the gross tumor margin, respectively, to account for possible ME of the tumors in all patients

  6. Skin Cancer of the Head and Neck with Perineural Invasion: Defining the Clinical Target Volumes Based on the Pattern of Failure

    Science.gov (United States)

    Gluck, Iris; Ibrahim, Mohannad; Popovtzer, Aron; Teknos, Theodoros N.; Chepeha, Douglas B; Prince, Mark E; Moyer, Jeffrey S; Bradford, Carol R; Eisbruch, Avraham

    2009-01-01

    Purpose To analyze patterns of failure in patients with head and neck cutaneous squamous cell carcinoma (HNCSCC) and clinical/radiological evidence of perineural invasion (CPNI), in order to define neural clinical target volume (CTV) for treatment planning. Methods Patients treated with 3D conformal or intensity modulated radiotherapy (IMRT) for HNCSCC with CPNI were included in the study. A retrospective review of the clinical charts, radiotherapy (RT) plans and radiological studies has been conducted. Results Eleven consecutive patients with HNCSCCs with CPNI were treated from 2000 through 2007. Most patients received multiple surgical procedures and RT courses. The most prevalent failure pattern was along cranial nerves (CNs), and multiple CNs were ultimately involved in the majority of cases. In all cases the involved CNs at recurrence were the main nerves innervating the primary tumor sites, as well as their major communicating nerves. We have found several distinct patterns of disease spread along specific CNs depending on the skin regions harboring the primary tumors, including multiple branches of CN V and VII. These patterns and the pertinent anatomy are detailed in the paper. Conclusions Predictable disease spread patterns along cranial nerves supplying the primary tumor sites were found in this study. Awareness of these patterns, as well as knowledge of the relevant cranial nerve anatomy, should be the basis for CTV definition and delineation for RT treatment planning. PMID:18938044

  7. Circumferential or sectored beam arrangements for stereotactic body radiation therapy (SBRT) of primary lung tumors: Effect on target and normal-structure dose-volume metrics

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Mara W. [Broad Institute of MIT and Harvard, Cambridge, MA (United States); Department of Physics, Brandeis University, Waltham, MA (United States); Kato, Catherine M. [Macalester College, St. Paul, MN (United States); Carson, Kelly M.P. [The University of North Carolina, Chapel Hill, NC (United States); Matsunaga, Nathan M. [Santa Clara University, Santa Clara, CA (United States); Arao, Robert F. [Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR (United States); Doss, Emily J. [Department of Internal Medicine, Providence St. Vincent Medical Center, Portland, OR (United States); McCracken, Charles L. [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Meng, Lu Z. [Department of Radiation Oncology, University of California Davis Comprehensive Cancer Center, Sacramento, CA (United States); Chen, Yiyi [Department of Public Health and Preventive Medicine, Oregon Health and Science University, Portland, OR (United States); Laub, Wolfram U.; Fuss, Martin [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Corvallis, OR (United States); Tanyi, James A., E-mail: tanyij@ohsu.edu [Department of Radiation Medicine, Oregon Health and Science University, Portland, OR (United States); Department of Nuclear Engineering and Radiation Health Physics, Oregon State University, Corvallis, OR (United States)

    2013-01-01

    To compare 2 beam arrangements, sectored (beam entry over ipsilateral hemithorax) vs circumferential (beam entry over both ipsilateral and contralateral lungs), for static-gantry intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) delivery techniques with respect to target and organs-at-risk (OAR) dose-volume metrics, as well as treatment delivery efficiency. Data from 60 consecutive patients treated using stereotactic body radiation therapy (SBRT) for primary non–small-cell lung cancer (NSCLC) formed the basis of this study. Four treatment plans were generated per data set: IMRT/VMAT plans using sectored (-s) and circumferential (-c) configurations. The prescribed dose (PD) was 60 Gy in 5 fractions to 95% of the planning target volume (PTV) (maximum PTV dose ∼ 150% PD) for a 6-MV photon beam. Plan conformality, R{sub 50} (ratio of volume circumscribed by the 50% isodose line and the PTV), and D{sub 2} {sub cm} (D{sub max} at a distance ≥2 cm beyond the PTV) were evaluated. For lungs, mean doses (mean lung dose [MLD]) and percent V{sub 30}/V{sub 20}/V{sub 10}/V{sub 5} Gy were assessed. Spinal cord and esophagus D{sub max} and D{sub 5}/D{sub 50} were computed. Chest wall (CW) D{sub max} and absolute V{sub 30}/V{sub 20}/V{sub 10}/V{sub 5} {sub Gy} were reported. Sectored SBRT planning resulted in significant decrease in contralateral MLD and V{sub 10}/V{sub 5} {sub Gy}, as well as contralateral CW D{sub max} and V{sub 10}/V{sub 5} {sub Gy} (all p < 0.001). Nominal reductions of D{sub max} and D{sub 5}/D{sub 50} for the spinal cord with sectored planning did not reach statistical significance for static-gantry IMRT, although VMAT metrics did show a statistically significant decrease (all p < 0.001). The respective measures for esophageal doses were significantly lower with sectored planning (p < 0.001). Despite comparable dose conformality, irrespective of planning configuration, R{sub 50} significantly improved with IMRT

  8. Synthesis of knowledge of the potential impacts of OCS (Outer Continental Shelf) oil and gas activities on fisheries. Volume 1. Appendix, annotated bibliography and data base descriptions for target species, distribution and abundance studies. Section 2. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the appendix is to present an annotated bibliography of published and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes descriptions of data bases that contain information related to target species distribution and abundance.

  9. Target volume delineation in individualized radiotherapy of non-surgical esophageal carcinoma%非手术食管癌个体化放疗的靶区勾画进展

    Institute of Scientific and Technical Information of China (English)

    营巧玲; 李前文; 杜云翔

    2014-01-01

    Individualized radiotherapy is the ideal model of radiation therapy, based on tailoring the treatment in a large num-ber of individual clinical, pathological and molecular genetic level. Two key problems exist in the implementation of individualized ra-diotherapy, one is how to identify and individually delineate the target volume of esophageal carcinoma, and the other is how to individ-ually implement the precise exposure. Due to technological advances and the renovation of equipment in radiotherapy for esophageal car-cinoma, the individualized implementation of the precise exposure has become possible. In recent years, with the advent of functional imaging, molecular imaging and other new technologies, it points out the future research direction of individualized tumor target volume delineation. This article reviewed the definition of the target volume in the individual radiotherapy of non-surgical esophageal carcinoma, which involves the application of new technologies such as anatomical imaging, functional imaging, hypoxia, molecular im-aging to individually identify and delineat the tumor target volume, including gross tumor volume, clinical tumor volume, planning tar-get volume, biological target volume and etc.%个体化放疗的实施取决于两个关键环节,首先是靶区的个体化识别和勾画,另一个是射线的个体化施照。由于放疗设备的更新和精确放疗技术的快速发展,实现射线个体化的精确施照成为可能。近年来,随着功能影像和分子显像等新技术的出现,指明了肿瘤个体化放疗靶区勾画的研究方向。本文对非手术食管癌患者个体化放疗的靶区勾画进行综述,内容涉及应用解剖影像、功能影像、乏氧和分子显像等新技术个体化识别和勾画非手术食管癌的放疗靶区,包括大体肿瘤靶区、临床靶区、计划靶区、生物靶区等。

  10. The morpho-PET with {sup 18}F-F.D.G. improves the definition of the target volume for the radiotherapy of child Hodgkin disease; Le morpho-TEP au 18F-FDG ameliore la definition du volume cible pour la radiotherapie des maladies de Hodgkin de l'enfant

    Energy Technology Data Exchange (ETDEWEB)

    Metwally, H.; Courbon, F.; David, I.; Blouet, A.; Izar, F.; Rives, M.; Filleron, T.; Vial, J.; Laprie, A. [Institut Claudius-Regaud, Toulouse, (France); Robert, A. [CHU Toulouse, (France)

    2009-05-15

    The objective is to study the impact of PET-T.D.M. images re-timing before chemotherapy with these ones of dosimetric scanner ( post chemotherapy) on the target volume determination and their inter observers variability among children receiving a closing radiotherapy for a Hodgkin disease. Conclusions: the inter observers variability for the clinical target volume (C.T.V.) definition is significantly reduced by the re-timing of initial PET-T.D.M. images on the ballistic scanner. This study illustrates the interest of the multidisciplinary cooperation between nuclear doctor and radiotherapist for the radiotherapy optimization. (N.C.)

  11. Determination of the optimal statistical uncertainty to perform electron-beam Monte Carlo absorbed dose estimation in the target volume; Determination de l'incertitude statistique optimale pour realiser un calcul de dose dans le volume cible en utilisant la methode de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Isambert, A.; Lefkopoulos, D. [Institut Gustave-Roussy, Medical Physics Dept., 94 - Villejuif (France); Brualla, L. [NCTeam, Strahlenklinik, Universitatsklinikum Essen (Germany); Benkebil, M. [DOSIsoft, 94 - Cachan (France)

    2010-04-15

    Purpose of study Monte Carlo based treatment planning system are known to be more accurate than analytical methods for performing absorbed dose estimation, particularly in and near heterogeneities. However, the required computation time can still be an issue. The present study focused on the determination of the optimum statistical uncertainty in order to minimise computation time while keeping the reliability of the absorbed dose estimation in treatments planned with electron-beams. Materials and methods Three radiotherapy plans (medulloblastoma, breast and gynaecological) were used to investigate the influence of the statistical uncertainty of the absorbed dose on the target volume dose-volume histograms (spinal cord, intra-mammary nodes and pelvic lymph nodes, respectively). Results The study of the dose-volume histograms showed that for statistical uncertainty levels (1 S.D.) above 2 to 3%, the standard deviation of the mean dose in the target volume calculated from the dose-volume histograms increases by at least 6%, reflecting the gradual flattening of the dose-volume histograms. Conclusions This work suggests that, in clinical context, Monte Carlo based absorbed dose estimations should be performed with a maximum statistical uncertainty of 2 to 3%. (authors)

  12. Toward optimal organ at risk sparing in complex volumetric modulated arc therapy: An exponential trade-off with target volume dose homogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Tol, Jim P., E-mail: j.tol@vumc.nl; Dahele, Max; Doornaert, Patricia; Slotman, Ben J.; Verbakel, Wilko F. A. R. [Department of Radiation Oncology, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam (Netherlands)

    2014-02-15

    Purpose: Conventional radiotherapy typically aims for homogenous dose in the planning target volume (PTV) while sparing organs at risk (OAR). The authors quantified and characterized the trade-off between PTV dose inhomogeneity (IH) and OAR sparing in complex head and neck volumetric modulated arc therapy plans. Methods: Thirteen simultaneous integrated boost plans were created per patient, for ten patients. PTV boost{sub (B)}/elective{sub (E)} optimization priorities were systematically increased. IH{sub B} and IH{sub E}, defined as (100% − V95%) + V107%, were evaluated against the average of the mean dose to the combined composite swallowing and combined salivary organs (D-OAR{sub comp}). To investigate the influence of OAR size and position with respect to PTV{sub B/E}, OAR dose was evaluated against a modified Euclidean distance (DM{sub B}/DM{sub E}) between OAR and PTV. Results: Although the achievable D-OAR{sub comp} for a given level of PTV IH differed between patients, excellent logarithmic fits described the D-OAR{sub comp}/IH{sub B} and IH{sub E} relationship in all patients (mean R{sup 2} of 0.98 and 0.97, respectively). Allowing an increase in average IH{sub B} and IH{sub E} over a clinically acceptable range, e.g., from 0.4% ± 0.5% to 2.0% ± 2.0% and 6.9% ± 2.8% to 14.8% ± 2.7%, respectively, corresponded to a decrease in average dose to the composite salivary and swallowing structures from 30.3 ± 6.5 to 23.6 ± 4.7 Gy and 32.5 ± 8.3 to 26.8 ± 9.3 Gy. The increase in PTV{sub E} IH was mainly accounted for by an increase in V107, by on average 5.9%, rather than a reduction in V95, which was on average only 2%. A linear correlation was found between the OAR dose to composite swallowing structures and contralateral parotid and submandibular gland, with DM{sub E} (R{sup 2} = 0.83, 0.88, 0.95). Only mean ipsilateral parotid dose correlated with DM{sub B} (R{sup 2} = 0.87). Conclusions: OAR sparing is highly dependent on the permitted PTV{sub B

  13. Synthesis of knowledge of the potential impacts of OCS (Outer Continental Shelf) oil and gas activities on fisheries. Volume 1. Appendix, annotated bibliography and data base descriptions for target species, distribution and abundance studies. Section 1, Part 2. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the appendix is to present an annotated bibliography of published and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes descriptions of data bases that contain information related to target species distribution and abundance. An index is provided at the end of each section to help the reader locate studies or data bases related to a particular species.

  14. Synthesis of knowledge of the potential impacts of OCS (Outer Continental Shelf) oil and gas activities on fisheries. Volume 1. Appendix, annotated bibliography, and data base descriptions for target species, distribution and abundance studies. Section 1, Part 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tear, L.M.

    1989-10-01

    The purpose of the appendix is to present an annotated bibliography of published and grey literature related to the distribution and abundance of select species of finfish and shellfish along the coasts of the United States. The volume also includes descriptions of databases that contain information related to target species distribution and abundance. An index is provided at the end of each section to help the reader locate studies or data bases related to a particular species.

  15. Methodologies for localizing loco-regional hypopharyngeal carcinoma recurrences in relation to FDG-PET positive and clinical radiation therapy target volumes

    DEFF Research Database (Denmark)

    Due, Anne Kirkebjerg; Korreman, Stine Sofia; Tomé, Wolfgang;

    2010-01-01

    Focal methods to determine the source of recurrence are presented, tested for reproducibility and compared to volumetric approaches with respect to the number of recurrences ascribed to the FDG-PET positive and high dose volumes.......Focal methods to determine the source of recurrence are presented, tested for reproducibility and compared to volumetric approaches with respect to the number of recurrences ascribed to the FDG-PET positive and high dose volumes....

  16. The development of PET/CT in determining gross tumor target volume of esophageal carcinoma in precise radiotherapy%PET/CT确定食管癌大体靶区的研究进展

    Institute of Scientific and Technical Information of China (English)

    张炜; 宋轶鹏; 姜翠芳

    2014-01-01

    随着功能影像及分子影像的发展,PET/CT逐渐成为辅助制定肿瘤最佳精确放疗计划的成像方式.许多研究支持18 F-FDG PET/CT用于精确放疗中食管癌的靶区勾画,然而18F-FDGPET/CT在食管癌靶区勾画中的有效性尚需进一步研究.该文主要对18F-FDG PET/CT用于食管癌原发病灶、区域转移淋巴结GTV勾画的应用价值及有效性等方面的研究进行综述.%As the development of functional and molecular imaging,PET/CT gradually becomes one of methods in optimizing cancer radiotherapy treatment planning.Currently,numerous hospitals routinely use 18F-FDG PET/CT for the delineation of target volume in esophageal carcinoma (EC).However,the validity of 18F-FDG PET/CT in the delineation of target volume for EC is limited and needs further clinical validation.This review focuses on the value and validity of 18F-FDG PET/CT in the delineation of gross tumor target volume of EC primary lesions and regional lymph nodes.

  17. Contribution of 18F-Fluoro-ethyl-tyrosine Positron Emission Tomography to Target Volume Delineation in Stereotactic Radiotherapy of Malignant Cranial Base Tumours: First Clinical Experience

    Directory of Open Access Journals (Sweden)

    Reinhold Graf

    2012-01-01

    Full Text Available Increased amino acid uptake has been demonstrated in intracerebral tumours and head and neck carcinomas of squamous cell origin. We investigated the potential impact of using 18F-fluoro-ethyl-tyrosine (18F-FET-PET/CT in addition to conventional imaging for gross tumour volume (GTV delineation in stereotactic radiotherapy of skull base tumours. The study population consisted of 14 consecutive patients with cranial base tumours (10 with squamous cell histology, 4 others. All patients underwent a FET-PET/CT examination in addition to contrast-enhanced CT and 11 patients underwent MRI. All tumours and histologic types showed increased FET uptake. The GTV was defined by all voxels showing hyperintensity in MRI or CT (GTVMRI/CT or enhancement in PET (GTVPET, forming a GTVcomposite that was used for the initial treatment fields. An additional volume of infiltrative growth outside the GTVMRI/CT of about 1.0 ± 2 cm3 (5% of the conventional volume was demonstrated by FET-PET only (GTVPETplus with significant enlargement (>10% of GTVMRI/CT in three patients. From existing data, we found correlation between cellular density and the standardized uptake value (SUV of FET. We were able to substantially reduce the volume of escalated radiation dose (GTVboost by 11 ± 2 cm3 (24% of the conventional volume.

  18. More Accurate Definition of Clinical Target Volume Based on the Measurement of Microscopic Extensions of the Primary Tumor Toward the Uterus Body in International Federation of Gynecology and Obstetrics Ib-IIa Squamous Cell Carcinoma of the Cervix

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Wen-Jia [Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Wu, Xiao [Department of Pathology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Xue, Ren-Liang; Lin, Xiang-Ying [Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Kidd, Elizabeth A. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Yan, Shu-Mei [Department of Pathology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong Province (China); Zhang, Yao-Hong [Department of Radiation Oncology, Chaozhou Hospital of Chaozhou City, Guangdong Province (China); Zhai, Tian-Tian; Lu, Jia-Yang; Wu, Li-Li; Zhang, Hao [Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Huang, Hai-Hua [Department of Pathology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Chen, Zhi-Jian; Li, De-Rui [Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China); Xie, Liang-Xi, E-mail: xieliangxi1@qq.com [Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong Province (China)

    2015-01-01

    Purpose: To more accurately define clinical target volume for cervical cancer radiation treatment planning by evaluating tumor microscopic extension toward the uterus body (METU) in International Federation of Gynecology and Obstetrics stage Ib-IIa squamous cell carcinoma of the cervix (SCCC). Patients and Methods: In this multicenter study, surgical resection specimens from 318 cases of stage Ib-IIa SCCC that underwent radical hysterectomy were included. Patients who had undergone preoperative chemotherapy, radiation, or both were excluded from this study. Microscopic extension of primary tumor toward the uterus body was measured. The association between other pathologic factors and METU was analyzed. Results: Microscopic extension toward the uterus body was not common, with only 12.3% of patients (39 of 318) demonstrating METU. The mean (±SD) distance of METU was 0.32 ± 1.079 mm (range, 0-10 mm). Lymphovascular space invasion was associated with METU distance and occurrence rate. A margin of 5 mm added to gross tumor would adequately cover 99.4% and 99% of the METU in the whole group and in patients with lymphovascular space invasion, respectively. Conclusion: According to our analysis of 318 SCCC specimens for METU, using a 5-mm gross tumor volume to clinical target volume margin in the direction of the uterus should be adequate for International Federation of Gynecology and Obstetrics stage Ib-IIa SCCC. Considering the discrepancy between imaging and pathologic methods in determining gross tumor volume extent, we recommend a safer 10-mm margin in the uterine direction as the standard for clinical practice when using MRI for contouring tumor volume.

  19. More Accurate Definition of Clinical Target Volume Based on the Measurement of Microscopic Extensions of the Primary Tumor Toward the Uterus Body in International Federation of Gynecology and Obstetrics Ib-IIa Squamous Cell Carcinoma of the Cervix

    International Nuclear Information System (INIS)

    Purpose: To more accurately define clinical target volume for cervical cancer radiation treatment planning by evaluating tumor microscopic extension toward the uterus body (METU) in International Federation of Gynecology and Obstetrics stage Ib-IIa squamous cell carcinoma of the cervix (SCCC). Patients and Methods: In this multicenter study, surgical resection specimens from 318 cases of stage Ib-IIa SCCC that underwent radical hysterectomy were included. Patients who had undergone preoperative chemotherapy, radiation, or both were excluded from this study. Microscopic extension of primary tumor toward the uterus body was measured. The association between other pathologic factors and METU was analyzed. Results: Microscopic extension toward the uterus body was not common, with only 12.3% of patients (39 of 318) demonstrating METU. The mean (±SD) distance of METU was 0.32 ± 1.079 mm (range, 0-10 mm). Lymphovascular space invasion was associated with METU distance and occurrence rate. A margin of 5 mm added to gross tumor would adequately cover 99.4% and 99% of the METU in the whole group and in patients with lymphovascular space invasion, respectively. Conclusion: According to our analysis of 318 SCCC specimens for METU, using a 5-mm gross tumor volume to clinical target volume margin in the direction of the uterus should be adequate for International Federation of Gynecology and Obstetrics stage Ib-IIa SCCC. Considering the discrepancy between imaging and pathologic methods in determining gross tumor volume extent, we recommend a safer 10-mm margin in the uterine direction as the standard for clinical practice when using MRI for contouring tumor volume

  20. Targeting Cydia pomonella (L.)(Lepidoptera: Tortricidae) Adults with Low Volume Applications of Insecticides Alone and in Combination with Sex Pheromone

    Science.gov (United States)

    Studies examined the effectiveness of adding insecticides to low volume sprays of a microencapsulated (MEC) sex pheromone to manage codling moth, Cydia pomonella (L). The activities of fifteen insecticides against the adult stage were first evaluated with a plastic cup assay. In general, moth longev...

  1. High-Grade Glioma Radiation Therapy Target Volumes and Patterns of Failure Obtained From Magnetic Resonance Imaging and {sup 18}F-FDOPA Positron Emission Tomography Delineations From Multiple Observers

    Energy Technology Data Exchange (ETDEWEB)

    Kosztyla, Robert, E-mail: rkosztyla@bccancer.bc.ca [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Chan, Elisa K.; Hsu, Fred [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Wilson, Don [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Department of Functional Imaging, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Ma, Roy; Cheung, Arthur [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Zhang, Susan [Department of Medical Physics, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Department of Functional Imaging, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Moiseenko, Vitali [Department of Radiation Medicine and Applied Sciences, University of California, San Diego, La Jolla, California (United States); Benard, Francois [Department of Functional Imaging, British Columbia Cancer Agency, Vancouver, British Columbia (Canada); Nichol, Alan [Department of Radiation Oncology, British Columbia Cancer Agency, Vancouver, British Columbia (Canada)

    2013-12-01

    Purpose: The objective of this study was to compare recurrent tumor locations after radiation therapy with pretreatment delineations of high-grade gliomas from magnetic resonance imaging (MRI) and 3,4-dihydroxy-6-[{sup 18}F]fluoro-L-phenylalanine ({sup 18}F-FDOPA) positron emission tomography (PET) using contours delineated by multiple observers. Methods and Materials: Nineteen patients with newly diagnosed high-grade gliomas underwent computed tomography (CT), gadolinium contrast-enhanced MRI, and {sup 18}F-FDOPA PET/CT. The image sets (CT, MRI, and PET/CT) were registered, and 5 observers contoured gross tumor volumes (GTVs) using MRI and PET. Consensus contours were obtained by simultaneous truth and performance level estimation (STAPLE). Interobserver variability was quantified by the percentage of volume overlap. Recurrent tumor locations after radiation therapy were contoured by each observer using CT or MRI. Consensus recurrence contours were obtained with STAPLE. Results: The mean interobserver volume overlap for PET GTVs (42% ± 22%) and MRI GTVs (41% ± 22%) was not significantly different (P=.67). The mean consensus volume was significantly larger for PET GTVs (58.6 ± 52.4 cm{sup 3}) than for MRI GTVs (30.8 ± 26.0 cm{sup 3}, P=.003). More than 95% of the consensus recurrence volume was within the 95% isodose surface for 11 of 12 (92%) cases with recurrent tumor imaging. Ten (91%) of these cases extended beyond the PET GTV, and 9 (82%) were contained within a 2-cm margin on the MRI GTV. One recurrence (8%) was located outside the 95% isodose surface. Conclusions: High-grade glioma contours obtained with {sup 18}F-FDOPA PET had similar interobserver agreement to volumes obtained with MRI. Although PET-based consensus target volumes were larger than MRI-based volumes, treatment planning using PET-based volumes may not have yielded better treatment outcomes, given that all but 1 recurrence extended beyond the PET GTV and most were contained by a 2-cm

  2. Costs and benefits of industrial reporting and voluntary targets for energy efficiency. A report to the Congress of the United States. Volume II: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This part sets forth the regulations for the Industrial Energy conservation Program established under Part E of Title III of the Act. It includes criteria and procedures for the identification of reporting corporations, reporting requirements, criteria and procedures for exemption from filing reports directly with DOE, voluntary industrial energy efficiency improvement targets and voluntary recovered materials utilization targets. The purpose of the program is to promote increased energy conservation by American industry and, as it relates to the use of recovered materials, to conserve valuable energy and scarce natural resources.

  3. State and Local Implementation of the No Child Left Behind Act. Volume VI--Targeting and Uses of Federal Education Funds

    Science.gov (United States)

    Chambers, Jay G.; Lam, Irene; Mahitivanichcha, Kanya; Esra, Phil; Shambaugh, Larisa; Stullich, Stephanie

    2009-01-01

    Achieving the goals of federal education legislation depends on how federal funds are distributed and used. Since the enactment of the Elementary and Secondary Education Act (ESEA) in 1965, various federal programs have been created to support educational improvement and target additional resources to meet the educational needs of children who are…

  4. 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography-Based Radiotherapy Target Volume Definition in Non-Small-Cell Lung Cancer: Delineation by Radiation Oncologists vs. Joint Outlining With a PET Radiologist?

    International Nuclear Information System (INIS)

    Purpose: 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) has benefits in target volume (TV) definition in radiotherapy treatment planning (RTP) for non-small-cell lung cancer (NSCLC); however, an optimal protocol for TV delineation has not been determined. We investigate volumetric and positional variation in gross tumor volume (GTV) delineation using a planning PET/CT among three radiation oncologists and a PET radiologist. Methods and Materials: RTP PET/CT scans were performed on 28 NSCLC patients (Stage IA-IIIB) of which 14 patients received prior induction chemotherapy. Three radiation oncologists and one PET radiologist working with a fourth radiation oncologist independently delineated the GTV on CT alone (GTVCT) and on fused PET/CT images (GTVPETCT). The mean percentage volume change (PVC) between GTVCT and GTVPETCT for the radiation oncologists and the PVC between GTVCT and GTVPETCT for the PET radiologist were compared using the Wilcoxon signed-rank test. Concordance index (CI) was used to assess both positional and volume change between GTVCT and GTVPETCT in a single measurement. Results: For all patients, a significant difference in PVC from GTVCT to GTVPETCT exists between the radiation oncologist (median, 5.9%), and the PET radiologist (median, -0.4%, p = 0.001). However, no significant difference in median concordance index (comparing GTVCT and GTVFUSED for individual cases) was observed (PET radiologist = 0.73; radiation oncologists = 0.66; p = 0.088). Conclusions: Percentage volume changes from GTVCT to GTVPETCT were lower for the PET radiologist than for the radiation oncologists, suggesting a lower impact of PET/CT in TV delineation for the PET radiologist than for the oncologists. Guidelines are needed to standardize the use of PET/CT for TV delineation in RTP.

  5. Study for identification of beneficial Uses of Space (BUS). Volume 2: Technical report. Book 3: Development and business analysis of space processed tungsten fox X-ray targets

    Science.gov (United States)

    1975-01-01

    The development plans, analysis of required R and D and production resources, the costs of such resources, and finally, the potential profitability of a commercial space processing opportunity for containerless melting and resolidification of tungsten are discussed. The aim is to obtain a form of tungsten which, when fabricated into targets for X-ray tubes, provides at least, a 50 percent increase in service life.

  6. Lipiodol injections for optimization of target volume delineation in a patient with a second tumor of the oropharynx. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Haderlein, Marlen; Merten, Ricarda; Stojanovic, Andrea; Speer, Stefan; Fietkau, Rainer; Ott, Oliver J. [University Hospitals of Erlangen, Department of Radiation Oncology, Erlangen (Germany); Scherl, Claudia [University Hospitals of Erlangen, Department of Otorhinolaryngology, Erlangen (Germany)

    2015-08-15

    Lipiodol injections were administered in the head and neck area to improve gross tumor volume (GTV) definition for small-volume re-irradiation of a 63-year-old previously irradiated patient with a second tumor of the oropharynx in the posterior wall with longitudinal ligament infiltration (cT4cN0cM0). The patient had dialysis-depending renal failure. On diagnostic computed tomography (CT), which was performed with intravenous contrast agent, the tumor in the oropharynx was not detectable. Because of dialysis-depending renal failure comorbidity, no contrast agent was applied in the planning CT and in the diagnostic magnetic resonance imaging (MRI) study. In each cross-sectional imaging study performed, the GTV, especially in craniocaudal extensions, was not safely delineable. Therefore, craniocaudal tumor margins were pharyngoscopically marked with Lipiodol injections, an iodine-containing contrast agent. In a second planning CT, the GTV could be defined with the help of the Lipiodol marks and small-volume re-irradiation was performed. No Lipiodol-associated side effects occurred in the patient. In the present case, the use of Lipiodol injections at the tumor margins facilitated the definition of the GTV. (orig.) [German] Anwendung von Lipiodolinjektionen im Kopf-Hals-Bereich zur Verbesserung der GTV-Definition bei einer kleinvolumigen Re-Bestrahlung eines 63-jaehrigen, vorbestrahlten Patienten mit einem Zweitmalignom im Oropharynx mit Infiltration des hinteren Laengsbandes (cT4cN0cM0). Nebenbefundlich bestand bei dem Patienten eine dialysepflichtige Niereninsuffizienz. Im initialen diagnostischen Kontrastmittel-CT der Hals und Thoraxregion war der Tumor nicht abgrenzbar, so dass das Bestrahlungsplanungs-CT in Anbetracht des diagnostischen CTs und der bekannten Niereninsuffizienz ohne intravenoeses Kontrastmittel durchgefuehrt wurde. Das diagnostische MRT (vgl. Abb. 1) wurde ebenfalls ohne intravenoeses Kontrastmittel durchgefuehrt wurden. In allen durchgefuehrten

  7. Impact of the target volume (prostate alone vs. prostate with seminal vesicles) and fraction dose (1.8 Gy vs. 2.0 Gy) on quality of life changes after external-beam radiotherapy for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Eble, Michael J. [Dept. of Radiotherapy, RWTH Aachen (Germany); Pinkawa, Michael; Piroth, Marc D.; Fischedick, Karin; Holy, Richard; Klotz, Jens; Nussen, Sandra; Krenkel, Barbara

    2009-11-15

    Purpose: to evaluate the impact of the clinical target volume (CTV) and fraction dose on quality of life (QoL) after external-beam radiotherapy (EBRT) for prostate cancer. Patients and methods: a group of 283 patients has been surveyed prospectively before, at the last day, at a median time of 2 months and 15 months after EBRT (70.2-72 Gy) using a validated questionnaire (Expanded Prostate Cancer Index Composite). FBRT of prostate alone (P, n = 70) versus prostate with seminal vesicles (PS, n = 213) was compared. Differences of fraction doses (1.8 Gy, n = 80, vs. 2.0 Gy, n = 69) have been evaluated in the patient group receiving a total dose of 72 Gy. Results: significantly higher bladder and rectum volumes were found at all dose levels for the patients with PS versus P within the CTV (p < 0.001). Similar volumes resulted in the groups with different fraction doses. Paradoxically, bowel function scores decreased significantly less 2 and 15 months after EBRT of PS versus P. 2 months after EBRT, patients with a fraction dose of 2.0 Gy versus 1.8 Gy reported pain with urination ({>=} once a day in 12% vs. 3%; p = 0.04) and painful bowel movements ({>=} rarely in 46% vs. 29%; p = 0.05) more frequently. No long-term differences were found. Conclusion: the risk of adverse QoL changes after EBRT for prostate cancer cannot be derived from the dose-volume histogram alone. Seminal vesicles can be included in the CTV up to a moderate total dose without adverse effects on QoL. Apart from a longer recovery period, higher fraction doses were not associated with higher toxicity. (orig.)

  8. Repeated CT scan in improving the reproducibility of grass tumor volume for moving target%重复CT扫描提高运动靶区勾画范围准确性研究

    Institute of Scientific and Technical Information of China (English)

    姜庆丰; 李光俊; 徐庆丰; 蒋晓芹; 柏森

    2010-01-01

    目的 通过运动靶区的模拟,探讨CT扫描对运动肿瘤靶区勾画范围准确性的影响,寻找提高运动靶区准确显示的方法.方法 以不同频率和振幅做简谐运动的靶区在CT机上扫描,每组分别重复扫描24次,然后对组内24次扫描图像每2、3次扫描随机分组融合.在Pinnacle计划系统中勾画靶区,分析运动对靶区沿运动方向长度的影响.结果 随运动幅度增加,CT扫描所得球形靶区最大体积与方形靶区最大长度都增加,球形靶区最小体积与方形靶区最小长度减小.运动频率对靶体积及长度影响较运动幅度小.对静止扫描长度为3.3 cm、运动频率为20和幅度为2 cm的方形运动靶区24次扫描中最大长度5.1 cm是最小长度2.1 cm的2.4倍.对组内24次扫描图像每1、2、3次融合,融合后靶区长度平均值±标准差分别为(3.77±1.20)、(4.18±0.91)、(4.52±0.59)cm.结论 随运动频率和幅度增加,CT扫描图像与靶区整个运动范围偏差增大.随扫描次数增加,融合所得靶区长度逐渐增加.在没有条件采取措施控制靶区运动情况下,重复CT扫描能简便有效地提高运动靶区勾画范围准确性.%Objective To find a method to improve the range accuracy of moving target such as peripheral lung tumors, since a single CT snapshot may not be accurate during the treatment process.Methods A simple harmonic motion phantom, embedded with a cube and a circular ball, was used to simulate the tumor motion. Individualized moving targets were scanned 24 times with different amplitudes and frequencies. Then the images were fused from every 1, 2 or 3 sets of CT scans. The GTV volume variation of circular target and the length variation of the cube target along the z axis were contoured and analyzed. Results As motion amplitude increased, the maximum of both circular target volume and cube target length was increased, while the minimum of the factors was decreased. Motion frequency affected the

  9. Geometrical differences in gross target volumes between 3DCT and 4DCT imaging in radiotherapy for non-small-cell lung cancer

    International Nuclear Information System (INIS)

    The aim of this study was to explore the characteristic of 3DCT scanning phases and estimate the comparative amount of respiration motion information included in 3DCT and 4DCT by comparing the volumetric and positional difference between the volumes from 3DCT and 4DCT for the radiotherapy of non-small-cell lung cancer (NSCLC). A total of 28 patients with NSCLC sequentially underwent 3DCT and 4DCT simulation scans of the thorax during free breathing. The 4DCT images with respiratory signal data were reconstructed and sorted into 10 phases throughout a respiratory cycle. GTV-3D from 3DCT, GTV-0%, GTV-20%, GTV-50% and GTV-70% from end-inspiration, mid-expiration, end-expiration and mid-inspiration of 4DCT, and the internal GTV (IGTV-10) from the fused phase of 4DCT were delineated based on the 50% phase image, respectively. The differences in the position, size, matching index (MI) and degree of inclusion (DI) for different volumes were evaluated. The variation in the centroid shifts of GTV-0% and GTV-3D, GTV-20% and GTV-3D, GTV-50% and GTV-3D, and GTV-90% and GTV-3D in the 3D direction was not significant (P = 0.990). The size ratios of GTV-0%, GTV-20%, GTV-50%, GTV-70% and IGTV-10 to GTV-3D were 0.94 ± 0.18, 0.95 ± 0.18, 0.98 ± 0.15, 1.00 ± 0.18 and 1.60 ± 0.55, respectively. DIs of GTV-3D in IGTV-10, and IGTV-10 in GTV-3D were 0.88 ± 0.14 and 0.59 ± 0.16 (P < 0.001). The 3DCT scanning phases are irregular. The CTV-to-ITV expansion should be isotropic when defining the ITV on the 3DCT. The internal GTV derived from 4DCT cannot completely include the GTV from 3DCT. An additional margin may be required when defining the ITV-based 4DCT

  10. Prospective evaluation of early treatment outcome in patients with meningiomas treated with particle therapy based on target volume definition with MRI and {sup 68}Ga-DOTATOC-PET

    Energy Technology Data Exchange (ETDEWEB)

    Combs, Stephanie E.; Welzel, Thomas; Habermehl, Daniel; Rieken, Stefan; Dittmar, Jan-Oliver; Kessel, Kerstin; Debus, Juergen [Univ. Hospital of Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany)], e-mail: Stephanie.Combs@med.uni-heidelberg.de; Jaekel, Oliver [Heidelberg Ion Therapy Center (HIT), Heidelberg (Germany); Haberkorn, Uwe [Univ. Hospital of Heidelberg, Dept. of Nuclear Medicine, Heidelberg (Germany)

    2013-04-15

    Purpose: To evaluate early treatment results and toxicity in patients with meningiomas treated with particle therapy. Material and methods: Seventy patients with meningiomas were treated with protons (n = 38) or carbon ion radiotherapy (n = 26). Median age was 49 years. Median age at treatment was 55 years, 24 were male (34%), and 46 were female (66%). Histology was benign meningioma in 26 patients (37%), atypical in 23 patients (33%) and anaplastic in four patients (6%). In 17 patients (24%) with skull base meningiomas diagnosis was based on the typical appearance of a meningioma. For benign meningiomas, total doses of 52.2-57.6 GyE were applied with protons. For high-grade lesions, the boost volume was 18 GyE carbon ions, with a median dose of 50 GyE applied as highly conformal radiation therapy. Nineteen patients were treated as re-irradiation. Treatment planning with MRI and 68-Ga-DOTATOC-PET was evaluated. Results: Very low rates of side effects developed, including headaches, nausea and dizziness. No severe treatment-related toxicity was observed. Local control for benign meningiomas was 100%. Five of 27 patients (19%) developed tumor recurrence during follow-up. Of these, four patients had been treated as re-irradiation for recurrent high-risk meningiomas. Actuarial local control after re-irradiation of high-risk meningiomas was therefore 67% at six and 12 months. In patients treated with primary radiotherapy, only one of 13 patients (8%) developed tumor recurrence 17 months after radiation therapy (photon and carbon ion boost). Conclusion: Continuous prospective follow-up and development of novel study concepts are required to fully exploit the long-term clinical data after particle therapy for meningiomas. To date, it may be concluded that when proton therapy is available, meningioma patients can be offered a treatment at least comparable to high-end photon therapy.

  11. 胰腺导管腺癌不同靶区勾画方法的稳定性研究%Stabilities of Different Strategies for Target Volume Delineation in Pancreatic Ductal Adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    李丹明; 穆庆霞; 孙新臣; 王沛沛

    2014-01-01

    Objective To compare the four various strategies [Radiation Therapy Oncology Group(RTOG),Oxford,Michigan and Selective Chemoradiation in Advanced Localized Pancreatic Cancer(SCALOP)]for target volume delineation in pancreatic ductal adenocarcinoma(PDAC). Methods Enhanced CT scanning was performed in 9 patients with pathologically proved PDAC, and planning target volumes(PTVs)were independently outlined by five radiotherapists according to the four different guidelines for target volume delineation.The size of PTVs,coefficient of vari-ance(COV),concordance index and Vintersection were compared quantificationally.Results The size of PTVs,Vintersection and concordance index were not significantly different between Ox-ford guideline and RTOG guideline(P>0.05),but were significantly different between RTOG or Oxford guidelines and Michigan or SCALOP guidelines(P0.05).Conclu-sion SCALOP and Michigan guidelines have better stability than RTOG and Oxford guidelines for target volume delineation in patients with PDAC.There are obvious differences in size of PTVs among the four various strategies.Further clinical evidence-based medical evidence is essen-tial to support the guideline that is beneficial for improving the survival of PDAC patients.%目的:研究4种[放射治疗肿瘤学组(RTOG)、牛津(Oxford)、密歇根(Michigan)和选择性放化疗协作组(SCALOP)]不同胰腺导管腺癌(PDAC)靶区勾画方法的差异。方法对9例病理确诊为 PDAC术后或未行手术的患者均行CT增强扫描,由5位医师在CT上根据4种不同的靶区定义独立勾画计划靶体积(PTVs)。比较9例患者的 RTOG、Oxford、Michigan和 SCALOP靶区勾画方法的 PTVs 情况,并以协方差(COV)、一致性指数(con-cordance index)和交集体积百分比(Vintersection)定量比较不同靶区勾画方法的勾画的稳定性。结果9例患者的 RTOG靶区勾画方法PTVs、Vintersection和 concordance index值与 Oxford

  12. 胶质母细胞瘤放射治疗靶区设计现状与思考%Target volume delineation for glioblastoma multiforme: current practice and advice

    Institute of Scientific and Technical Information of China (English)

    李明焕; 孔莉; 于金明

    2013-01-01

    胶质母细胞瘤(GBM)术后放疗大都采用MRI与CT融合影像来勾画靶区,但是否包含瘤周水肿区尚有争议.根据术后、放疗后的复发范围,不论靶区设计是否包含水肿区,大部分复发都发生在磁共振(MRI)显示增强原发肿瘤灶外2 cm之内,瘤周水肿程度与复发模式无必然关系.GBM的临床和病理特征对放化疗疗效预测和预后也有重要指导意义.GBM的靶区设计趋向于个体化,可在保证疗效的同时减少治疗毒性.%The use of adjuvant extemal-beam RT is well established in the postoperative treatment of glioblastoma multiforme (CBM).It is consensus that target volume should be determined based on the fusion images of MRI and CT,but the inclusion of peritumoural edematous is controversial.The vast majority of recurrences occur within 2 cm of the original tumor site or " in radiation field".There is no inevitable relation between the degree of peritumoral edema and recurrence model.The clinical and pathological characteristics may be as predictive and prognostic factors for the treatment of GBM.Target volume delineation for CBM tend to individual,which can maintain known outcomes and reduce treatment toxicity.

  13. Image-Guided Radiation Therapy for Muscle-Invasive Carcinoma of the Urinary Bladder with Cone Beam CT Scan: Use of Individualized Internal Target Volumes for a Single Patient

    Directory of Open Access Journals (Sweden)

    Gagan Saini

    2012-09-01

    Full Text Available Introduction: While planning radiation therapy (RT for a carcinoma of the urinary bladder (CaUB, the intra-fractional variation of the urinary bladder (UB volume due to filling-up needs to be accounted for. This internal target volume (ITV is obtained by adding internal margins (IM to the contoured bladder. This study was planned to propose a method of acquiring individualized ITVs for each patient and to verify their reproducibility. Methods: One patient with CaUB underwent simulation with the proposed ‘bladder protocol’. After immobilization, a planning CT scan on empty bladder was done. He was then given 300 ml of water to drink and the time (T was noted. Planning CT scans were performed after 20 min (T+20, 30 min (T+30 and 40 min (T+40. The CT scan at T+20 was co-registered with the T+30 and T+40 scans. The bladder volumes at 20, 30 and 40 min were then contoured as CTV20, CTV30 and CTV40 to obtain an individualized ITV for our patient. For daily treatment, he was instructed to drink water as above, and the time was noted; treatment was started after 20 min. Daily pre- and post-treatment cone beam CT (CBCT scans were done. The bladder visualized on the pre-treatment CBCT scan was compared with CTV20 and on the post-treatment CBCT scan with CTV30. Results: In total, there were 65 CBCT scans (36 pre- and 29 post-treatment. Individualized ITVs were found to be reproducible in 93.85% of all instances and fell outside in 4 instances. Conclusions: The proposed bladder protocol can yield a reproducible estimation of the ITV during treatment; this can obviate the need for taking standard IMs.

  14. Volumetric-modulated arc therapy for left-sided breast cancer and all regional nodes improves target volumes coverage and reduces treatment time and doses to the heart and left coronary artery, compared with a field-in-field technique

    International Nuclear Information System (INIS)

    We compared two intensity-modulated radiotherapy techniques for left-sided breast treatment, involving lymph node irradiation including the internal mammary chain. Inverse planned arc-therapy (VMAT) was compared with a forward-planned multi-segment technique with a mono-isocenter (MONOISO). Ten files were planned per technique, delivering a 50-Gy dose to the breast and 46.95 Gy to nodes, within 25 fractions. Comparative endpoints were planning target volume (PTV) coverage, dose to surrounding structures, and treatment delivery time. PTV coverage, homogeneity and conformality were better for two arc VMAT plans; V95%PTV-T was 96% for VMAT vs 89.2% for MONOISO. Homogeneity index (HI)PTV-T was 0.1 and HIPTV-N was 0.1 for VMAT vs 0.6 and 0.5 for MONOISO. Treatment delivery time was reduced by a factor of two using VMAT relative to MONOISO (84 s vs 180 s). High doses to organs at risk were reduced (V30left lung = 14% using VMAT vs 24.4% with MONOISO; dose to 2% of the volume (D2%)heart = 26.1 Gy vs 32 Gy), especially to the left coronary artery (LCA) (D2%LCA = 34.4 Gy vs 40.3 Gy). However, VMAT delivered low doses to a larger volume, including contralateral organs (mean dose [Dmean]right lung = 4 Gy and Dmeanright breast = 3.2 Gy). These were better protected using MONOISO plans (Dmeanright lung = 0.8 Gy and Dmeanright breast = 0.4 Gy). VMAT improved PTV coverage and dose homogeneity, but clinical benefits remain unclear. Decreased dose exposure to the LCA may be clinically relevant. VMAT could be used for complex treatments that are difficult with conventional techniques. Patient age should be considered because of uncertainties concerning secondary malignancies. (author)

  15. Clinical Validation of Atlas-Based Auto-Segmentation of Multiple Target Volumes and Normal Tissue (Swallowing/Mastication) Structures in the Head and Neck

    International Nuclear Information System (INIS)

    . Conclusion: Multiple-subject ABAS of computed tomography images proved to be a useful novel tool in the rapid delineation of target and normal tissues. Although editing of the autocontours is inevitable, a substantial time reduction was achieved using editing, instead of manual contouring (180 vs. 66 min).

  16. Clinical Validation of Atlas-Based Auto-Segmentation of Multiple Target Volumes and Normal Tissue (Swallowing/Mastication) Structures in the Head and Neck

    Energy Technology Data Exchange (ETDEWEB)

    Teguh, David N. [Department of Radiation Oncology, Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Levendag, Peter C., E-mail: p.levendag@erasmusmc.nl [Department of Radiation Oncology, Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Voet, Peter W.J.; Al-Mamgani, Abrahim [Department of Radiation Oncology, Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Han Xiao; Wolf, Theresa K.; Hibbard, Lyndon S. [Elekta-CMS Software, Maryland Heights, MO 63043 (United States); Nowak, Peter; Akhiat, Hafid; Dirkx, Maarten L.P.; Heijmen, Ben J.M.; Hoogeman, Mischa S. [Department of Radiation Oncology, Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2011-11-15

    . Conclusion: Multiple-subject ABAS of computed tomography images proved to be a useful novel tool in the rapid delineation of target and normal tissues. Although editing of the autocontours is inevitable, a substantial time reduction was achieved using editing, instead of manual contouring (180 vs. 66 min).

  17. New method for rapid solid-phase extraction of large-volume water samples and its application to non-target screening of North Sea water for organic contaminants by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Weigel, S; Bester, K; Hühnerfuss, H

    2001-03-30

    A method has been developed that allows the solid-phase extraction of microorganic compounds from large volumes of water (10 l) for non-target analysis of filtered seawater. The filtration-extraction system is operated with glass fibre filter candles and the polymeric styrene-divinylbenzene sorbent SDB-1 at flow-rates as high as 500 ml/min. Recovery studies carried out for a couple of model substances covering a wide range of polarity and chemical classes revealed a good performance of the method. Especially for polar compounds (log Kow 3.3-0.7) quantitative recovery was achieved. Limits of detection were between 0.1 and 0.7 ng/l in the full scan mode of the MS. The suitability of the method for the analysis of marine water samples is demonstrated by the non-target screening of water from the German Bight for the presence of organic contaminants. In the course of this screening a large variety of substances was identified including pesticides, industrial chemicals and pharmaceuticals. For some of the identified compounds their occurrence in marine ecosystems has not been reported before, such as dichloropyridines, carbamazepine, propyphenazone and caffeine.

  18. High-risk clinical target volume delineation in CT-guided cervical cancer brachytherapy - Impact of information from FIGO stage with or without systematic inclusion of 3D documentation of clinical gynecological examination

    Energy Technology Data Exchange (ETDEWEB)

    Hegazy, Neamat [Dept. of Radiotherapy, Comprehensive Cancer Centre Vienna, Medical Univ. of Vienna, Vienna (Austria); Dept. of Clinical Oncology, Medical Univ. of Alexandria, Alexandria (Egypt); Poetter Rickard; Kirisits, Christian [Dept. of Radiotherapy, Comprehensive Cancer Centre Vienna, Medical Univ. of Vienna, Vienna (Austria); Christian Doppler Lab. for Medical Radiation Research for Radiation Oncology, Medical Univ. Vienna (Austria); Berger, Daniel; Federico, Mario; Sturdza, Alina; Nesvacil, Nicole [Dept. of Radiotherapy, Comprehensive Cancer Centre Vienna, Medical Univ. of Vienna, Vienna (Austria)], e-mail: nicole.nesvacil@meduniwien.ac.at

    2013-10-15

    Purpose: The aim of the study was to improve computed tomography (CT)-based high-risk clinical target volume (HR CTV) delineation protocols for cervix cancer patients, in settings without any access to magnetic resonance imaging (MRI) at the time of brachytherapy. Therefore the value of a systematic integration of comprehensive three-dimensional (3D) documentation of repetitive gynecological examination for CT-based HR CTV delineation protocols, in addition to information from FIGO staging, was investigated. In addition to a comparison between reference MRI contours and two different CT-based contouring methods (using complementary information from FIGO staging with or without additional 3D clinical drawings), the use of standardized uterine heights was also investigated. Material and methods: Thirty-five cervix cancer patients with CT- and MR-images and 3D clinical drawings at time of diagnosis and brachytherapy were included. HR CTV{sub stage} was based on CT information and FIGO stage. HR CTV{sub stage} {sub +3Dclin} was contoured on CT using FIGO stage and 3D clinical drawing. Standardized HR CTV heights were: 1/1, 2/3 and 1/2 of uterine height. MRI-based HR CTV was delineated independently. Resulting widths, thicknesses, heights, and volumes of HR CTV{sub stage}, HR CTV{sub stage+3Dclin} and MRI-based HR CTV contours were compared. Results: The overall normalized volume ratios (mean{+-}SD of CT/MRI{sub ref} volume) of HR CTV{sub stage} and HR{sub stage+3Dclin} were 2.6 ({+-}0.6) and 2.1 ({+-}0.4) for 1/1 and 2.3 ({+-}0.5) and 1.8 ({+-}0.4), for 2/3, and 1.9 ({+-}0.5) and 1.5 ({+-}0.3), for 1/2 of uterine height. The mean normalized widths were 1.5{+-}0.2 and 1.2{+-}0.2 for HR CTV{sub stage} and HR CTV{sub stage+3Dclin}, respectively (p < 0.05). The mean normalized heights for HR CTV{sub stage} and HR CTV{sub stage+3Dclin} were both 1.7{+-}0.4 for 1/1 (p < 0.05.), 1.3{+-}0.3 for 2/3 (p < 0.05) and 1.1{+-}0.3 for 1/2 of uterine height. Conclusion: CT-based HR

  19. Time-Adjusted Internal Target Volume: A Novel Approach Focusing on Heterogeneity of Tumor Motion Based on 4-Dimensional Computed Tomography Imaging for Radiation Therapy Planning of Lung Cancer

    International Nuclear Information System (INIS)

    Purpose: To consider nonuniform tumor motion within the internal target volume (ITV) by defining time-adjusted ITV (TTV), a volume designed to include heterogeneity of tumor existence on the basis of 4-dimensional computed tomography (4D-CT). Methods and Materials: We evaluated 30 lung cancer patients. Breath-hold CT (BH-CT) and free-breathing 4D-CT scans were acquired for each patient. The tumors were manually delineated using a lung CT window setting (window, 1600 HU; level, −300 HU). Tumor in BH-CT images was defined as gross tumor volume (GTV), and the sum of tumors in 4D-CT images was defined as ITV-4D. The TTV images were generated from the 4D-CT datasets, and the tumor existence probability within ITV-4D was calculated. We calculated the TTV80 value, which is the percentage of the volume with a tumor existence probability that exceeded 80% on ITV-4D. Several factors that affected the TTV80 value, such as the ITV-4D/GTV ratio or tumor centroid deviation, were evaluated. Results: Time-adjusted ITV images were acquired for all patients, and tumor respiratory motion heterogeneity was visualized. The median (range) ITV-4D/GTV ratio and median tumor centroid deviation were 1.6 (1.0-4.1) and 6.3 mm (0.1-30.3 mm), respectively. The median TTV80 value was 43.3% (2.9-98.7%). Strong correlations were observed between the TTV80 value and the ITV-4D/GTV ratio (R=−0.71) and tumor centroid deviation (R=−0.72). The TTV images revealed the tumor motion pattern features within ITV. Conclusions: The TTV images reflected nonuniform tumor motion, and they revealed the tumor motion pattern features, suggesting that the TTV concept may facilitate various aspects of radiation therapy planning of lung cancer while incorporating respiratory motion in the future

  20. Time-Adjusted Internal Target Volume: A Novel Approach Focusing on Heterogeneity of Tumor Motion Based on 4-Dimensional Computed Tomography Imaging for Radiation Therapy Planning of Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nishibuchi, Ikuno [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Hiroshima Prefectural Hospital, Hiroshima (Japan); Kimura, Tomoki, E-mail: tkkimura@hiroshima-u.ac.jp [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Nakashima, Takeo; Ochi, Yusuke [Division of Radiation Therapy, Hiroshima University Hospital, Hiroshima (Japan); Takahashi, Ippei; Doi, Yoshiko; Kenjo, Masahiro; Kaneyasu, Yuko; Ozawa, Syuichi; Murakami, Yuji [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Wadasaki, Koichi [Department of Radiation Oncology, Hiroshima Prefectural Hospital, Hiroshima (Japan); Nagata, Yasushi [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan)

    2014-08-01

    Purpose: To consider nonuniform tumor motion within the internal target volume (ITV) by defining time-adjusted ITV (TTV), a volume designed to include heterogeneity of tumor existence on the basis of 4-dimensional computed tomography (4D-CT). Methods and Materials: We evaluated 30 lung cancer patients. Breath-hold CT (BH-CT) and free-breathing 4D-CT scans were acquired for each patient. The tumors were manually delineated using a lung CT window setting (window, 1600 HU; level, −300 HU). Tumor in BH-CT images was defined as gross tumor volume (GTV), and the sum of tumors in 4D-CT images was defined as ITV-4D. The TTV images were generated from the 4D-CT datasets, and the tumor existence probability within ITV-4D was calculated. We calculated the TTV{sub 80} value, which is the percentage of the volume with a tumor existence probability that exceeded 80% on ITV-4D. Several factors that affected the TTV{sub 80} value, such as the ITV-4D/GTV ratio or tumor centroid deviation, were evaluated. Results: Time-adjusted ITV images were acquired for all patients, and tumor respiratory motion heterogeneity was visualized. The median (range) ITV-4D/GTV ratio and median tumor centroid deviation were 1.6 (1.0-4.1) and 6.3 mm (0.1-30.3 mm), respectively. The median TTV{sub 80} value was 43.3% (2.9-98.7%). Strong correlations were observed between the TTV{sub 80} value and the ITV-4D/GTV ratio (R=−0.71) and tumor centroid deviation (R=−0.72). The TTV images revealed the tumor motion pattern features within ITV. Conclusions: The TTV images reflected nonuniform tumor motion, and they revealed the tumor motion pattern features, suggesting that the TTV concept may facilitate various aspects of radiation therapy planning of lung cancer while incorporating respiratory motion in the future.

  1. CT/MRI融合图像在盆腔肿瘤放疗靶区勾画中的应用%Application of CT/MRI Image Fusion in the Delineating of the Gross Tumor Target Volumes in the Radiotherapy for Pelvic Cavity Tumor

    Institute of Scientific and Technical Information of China (English)

    张海南; 汤日杰; 张书旭; 蔡霜

    2011-01-01

    Objective To study the value of application of CT/MRI image fusion in the delineating of the gross tumor target volumes in the radiotherapy for pelvic tumor in the middle-aged and elderly patients. Methods Nineteen patients suffering from pelvic tumor underwent CT and MRI examination within one week.All CT and MRI images were manually transported to the Nucletron PLATO Radiation Treatment Planning System(V 8.0, Philips medical corporation), and CT/MRI images were processed for image fusion.The experienced radiotherapeutic physicians delineated and analyzed the target volume of CT and MRI images, and gross tumor target volume of the CT/MR image fusion. Results The gross tumor target volume of the CT/MR image fusion relative the target volume of CT increased 6.29%,and relative MRI raised 11.84%,CT/MRI image fusion is superior to single CT and MRI image in the delineation of the gross tumor target volume, which was verified by test. Conclusion The technology of CT/MR image fusion can help to confirm target volume for pelvic tumor which will improve the accuracy in demarcating of the gross tumor target volume of pelvic cavity tumor, and promote the diagnosis and treatment of pelvic cavity tumor.%目的 探讨CT/MRI融合图像在中老年盆腔肿瘤放疗靶区(GTV)勾画中的应用价值.方法 19例盆腔肿瘤患者均在1周内分别进行CT、MRI异机非同步扫描.全部CT和MRI图像手工配准后传送至飞利浦公司的PINNACLE V8.0放射治疗计划系统,并进行图像融合.由有经验的放疗科医师对CT靶区、MRI靶区及CT与MR融合图像肿瘤靶区(GTV)进行勾画及评价分析.结果 GTVFUSION相对GTVCT提高了6.29%、相对GTVMRI提高了11.84%,融合图像对GTV的勾画明显优于单独CT图像或MRI图像.结论 CT/MRI图像融合技术有利于盆腔肿瘤靶区的确定,提高了临床对盆腔肿瘤靶区(GTV)勾画的准确率,利于患者的诊治.

  2. Deuterium High Pressure Target

    CERN Document Server

    Perevozchikov, V; Vinogradov, Yu I; Vikharev, M D; Ganchuk, N S; Golubkov, A N; Grishenchkin, S K; Demin, A M; Demin, D L; Zinov, V G; Kononenko, A A; Lobanov, V N; Malkov, I L; Yukhimchuk, S A

    2001-01-01

    The design of the deuterium high-pressure target is presented. The target having volume of 76 cm^3 serves to provide the experimental research of muon catalyzed fusion reactions in ultra-pure deuterium in the temperature range 80-800 K under pressures of up to 150 MPa. The operation of the main systems of the target is described: generation and purification of deuterium gas, refrigeration, heating, evacuation, automated control system and data collection system.

  3. Deuterium high pressure target

    International Nuclear Information System (INIS)

    The design of the deuterium high-pressure target is presented. The target having volume of 76 cm3 serves to provide the experimental research of muon catalyzed fusion reactions in ultra-pure deuterium in the temperature range 80-800 K under pressures of up to 150 MPa. The operation of the main systems of the target is described: generation and purification of deuterium gas, refrigeration, heating, evacuation, automated control system and data collection system

  4. Laser program annual report, 1977. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Bender, C.F.; Jarman, B.D. (eds.)

    1978-07-01

    This volume contains detailed information on each of the following sections: (1) fusion target design, (2) target fabrication, (3) laser fusion experiments and analysis, (4) advanced lasers, (5) systems and applications studies, and (6) laser isotope separation program. (MOW)

  5. Laser program annual report, 1977. Volume 2

    International Nuclear Information System (INIS)

    This volume contains detailed information on each of the following sections: (1) fusion target design, (2) target fabrication, (3) laser fusion experiments and analysis, (4) advanced lasers, (5) systems and applications studies, and (6) laser isotope separation program

  6. A teaching intervention in a contouring dummy run improved target volume delineation in locally advanced non-small cell lung cancer. Reducing the interobserver variability in multicentre clinical studies

    Energy Technology Data Exchange (ETDEWEB)

    Schimek-Jasch, Tanja; Prokic, Vesna; Doll, Christian; Grosu, Anca-Ligia; Nestle, Ursula [University Medical Center Freiburg, Department of Radiation Oncology, Freiburg (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); German Cancer Consortium (DKTK) partner site: Freiburg, Heidelberg (Germany); Troost, Esther G.C. [Maastricht University Medical Centre, Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht (Netherlands); Ruecker, Gerta [University Medical Center Freiburg, Institute for Medical Biometry and Statistics, Centre for Medical Biometry and Medical Informatics, Freiburg (Germany); Avlar, Melanie [German Cancer Research Center (DKFZ), Heidelberg (Germany); Duncker-Rohr, Viola [Ortenau-Klinikum Offenburg-Gengenbach, Department of Radiation Oncology, Gengenbach (Germany); Mix, Michael [University Medical Center Freiburg, Department of Nuclear Medicine, Freiburg (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); German Cancer Consortium (DKTK) partner site: Freiburg, Heidelberg (Germany)

    2015-02-10

    Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(κ) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study

  7. Distribution pattern of lymph node metastases and its implication in individualized radiotherapeutic clinical target volume delineation of regional lymph nodes in patients with stage IA to IIA cervical cancer

    International Nuclear Information System (INIS)

    To study the distribution pattern of lymph node metastases of stage IA to IIA cervical cancer and to clarify the individualized clinical target volume delineation of regional lymph nodes (CTVn). A total of 665 cases with International Federation Gynecology and Obstetrics stage IA to IIA cervical cancer who underwent radical hysterectomy and pelvic lymphadenectomy were retrospectively reviewed. The clinicopathological factors related to lymph node metastases were analyzed using logistic regression analysis. Pelvic lymph node metastases were found in 168 of 665 patients resulting in a metastasis rate of 25.3%. Binary logistic regression analysis showed that age, lymph vascular space involvement, and deep stromal invasion statistically influenced pelvic lymph node metastases (p = 0.017, < 0.001, < 0.001, respectively). Pathological morphology type, lymph node metastases of the obturator, the external iliac and internal iliac, and the para-aortic had a strong influence on lymph node metastases of the common iliac (p = 0.022, 0.003, < 0.001, 0.009, respectively). Tumor size and lymph node metastases of the common iliac were significantly related to lymph node metastases of the para-aortic (p = 0.045, < 0.001, respectively). Lymph node metastases of the obturator, the external iliac and internal iliac were strongly correlated to lymph node metastases of the circumflex iliac node distal to the external iliac node (CINDEIN; p = 0.027, 0.024, respectively). Factors related to lymph node metastases should be comprehensively considered to design and tailor CTVn for radiotherapy of cervical cancer. Selective regional irradiation including the correlated lymphatic drainage regions should be performed

  8. Patterns of Local-Regional Failure in Completely Resected Stage IIIA(N2) Non-Small Cell Lung Cancer Cases: Implications for Postoperative Radiation Therapy Clinical Target Volume Design

    International Nuclear Information System (INIS)

    Purpose: To analyze patterns of local-regional failure (LRF) for completely resected stage IIIA(N2) non-small cell lung cancer (NSCLC) patients treated in our hospital and to propose a clinical target volume (CTV) for postoperative radiation therapy (PORT) in these patients. Methods and Materials: From 2005 to 2011, consecutive patients with pT1-3N2 NSCLC who underwent complete resection in our hospital but who did not receive PORT were identified. The patterns of first LRF were assessed and evaluated as to whether these areas would be encompassed by our proposed PORT CTV. Results: With a median follow-up of 24 months, 173 of 250 patients (69.2%) experienced disease recurrence. Of the 54 patients with LRF as the first event, 48 (89%) had recurrence within the proposed PORT CTV, and 6 (11%) had failures occurring both within and outside the proposed CTV (all of which occurred in patients with right-lung cancer). Ninety-three percent of failure sites (104 of 112) would have been contained within the proposed PORT CTV. For left-sided lung cancer, the most common lymph node station failure site was 4R, followed by 7, 4L, 6, 10L, and 5. For right-sided lung cancer, the most common site was station 2R, followed by 10R, 4R, and 7. Conclusions: LRF following complete surgery was an important and potentially preventable pattern of failure in stage IIIA(N2) patients. Ipsilateral superior mediastinal recurrences dominated for right-sided tumors, whereas left-sided tumors frequently involved the bilateral superior mediastinum. Most of the LRF sites would have been covered by the proposed PORT CTV. A prospective investigation of patterns of failure after PORT (following our proposed CTV delineation guideline) is presently underway and will be reported in a separate analysis

  9. Sequential (gemcitabine/vinorelbine and concurrent (gemcitabine radiochemotherapy with FDG-PET-based target volume definition in locally advanced non-small cell lung cancer: first results of a phase I/II study

    Directory of Open Access Journals (Sweden)

    Stanzel Sven

    2007-06-01

    Full Text Available Abstract Background The aim of the study was to determine the maximal tolerated dose (MTD of gemcitabine every two weeks concurrent to radiotherapy, administered during an aggressive program of sequential and simultaneous radiochemotherapy for locally advanced, unresectable non-small cell lung cancer (NSCLC and to evaluate the efficacy of this regime in a phase II study. Methods 33 patients with histologically confirmed NSCLC were enrolled in a combined radiochemotherapy protocol. 29 patients were assessable for evaluation of toxicity and tumor response. Treatment included two cycles of induction chemotherapy with gemcitabine (1200 mg/m2 and vinorelbine (30 mg/m2 at day 1, 8 and 22, 29 followed by concurrent radiotherapy (2.0 Gy/d; total dose 66.0 Gy and chemotherapy with gemcitabine every two weeks at day 43, 57 and 71. Radiotherapy planning included [18F] fluorodeoxyglucose positron emission tomography (FDG PET based target volume definition. 10 patients were included in the phase I study with an initial gemcitabine dose of 300 mg/m2. The dose of gemcitabine was increased in steps of 100 mg/m2 until the MTD was realized. Results MTD was defined for the patient group receiving gemcitabine 500 mg/m2 due to grade 2 (next to grade 3 esophagitis in all patients resulting in a mean body weight loss of 5 kg (SD = 1.4 kg, representing 8% of the initial weight. These patients showed persisting dysphagia 3 to 4 weeks after completing radiotherapy. In accordance with expected complications as esophagitis, dysphagia and odynophagia, we defined the MTD at this dose level, although no dose limiting toxicity (DLT grade 3 was reached. In the phase I/II median follow-up was 15.7 months (4.1 to 42.6 months. The overall response rate after completion of therapy was 64%. The median overall survival was 19.9 (95% CI: [10.1; 29.7] months for all eligible patients. The median disease-free survival for all patients was 8.7 (95% CI: [2.7; 14.6] months. Conclusion

  10. Sequential (gemcitabine/vinorelbine) and concurrent (gemcitabine) radiochemotherapy with FDG-PET-based target volume definition in locally advanced non-small cell lung cancer: first results of a phase I/II study

    International Nuclear Information System (INIS)

    The aim of the study was to determine the maximal tolerated dose (MTD) of gemcitabine every two weeks concurrent to radiotherapy, administered during an aggressive program of sequential and simultaneous radiochemotherapy for locally advanced, unresectable non-small cell lung cancer (NSCLC) and to evaluate the efficacy of this regime in a phase II study. 33 patients with histologically confirmed NSCLC were enrolled in a combined radiochemotherapy protocol. 29 patients were assessable for evaluation of toxicity and tumor response. Treatment included two cycles of induction chemotherapy with gemcitabine (1200 mg/m2) and vinorelbine (30 mg/m2) at day 1, 8 and 22, 29 followed by concurrent radiotherapy (2.0 Gy/d; total dose 66.0 Gy) and chemotherapy with gemcitabine every two weeks at day 43, 57 and 71. Radiotherapy planning included [18F] fluorodeoxyglucose positron emission tomography (FDG PET) based target volume definition. 10 patients were included in the phase I study with an initial gemcitabine dose of 300 mg/m2. The dose of gemcitabine was increased in steps of 100 mg/m2 until the MTD was realized. MTD was defined for the patient group receiving gemcitabine 500 mg/m2 due to grade 2 (next to grade 3) esophagitis in all patients resulting in a mean body weight loss of 5 kg (SD = 1.4 kg), representing 8% of the initial weight. These patients showed persisting dysphagia 3 to 4 weeks after completing radiotherapy. In accordance with expected complications as esophagitis, dysphagia and odynophagia, we defined the MTD at this dose level, although no dose limiting toxicity (DLT) grade 3 was reached. In the phase I/II median follow-up was 15.7 months (4.1 to 42.6 months). The overall response rate after completion of therapy was 64%. The median overall survival was 19.9 (95% CI: [10.1; 29.7]) months for all eligible patients. The median disease-free survival for all patients was 8.7 (95% CI: [2.7; 14.6]) months. After induction chemotherapy, the maximum tolerated dose

  11. Effects of breast-air and breast-lung interfaces on the dose rate at the planning target volume of a MammoSite catheter for Yb-169 and Ir-192 HDR sources

    Energy Technology Data Exchange (ETDEWEB)

    Cazeca, Mario J.; Medich, David C.; Munro, John J. III [Department of Physics and Applied Physics, University of Massachusetts Lowell, 1 University Avenue, Lowell, Massachusetts 01854 (United States); Radiation Laboratory, University of Massachusetts Lowell, 1 University Avenue, Lowell, Massachusetts 01854 (United States); Source Production and Equipment Co., Inc., 113 Teal Street, St. Rose, Louisiana 70087 (United States)

    2010-08-15

    Purpose: To study the effects of the breast-air and breast-lung interfaces on the absorbed dose within the planning target volume (PTV) of a MammoSite balloon dose delivery system as well as the effect of contrast material on the dose rate in the PTV. Methods: The Monte Carlo MCNP5 code was used to simulate dose rate in the PTV of a 2 cm radius MammoSite balloon dose delivery system. The simulations were carried out using an average female chest phantom (AFCP) and a semi-infinite water phantom for both Yb-169 and Ir-192 high dose rate sources for brachytherapy application. Gastrografin was introduced at varying concentrations to study the effect of contrast material on the dose rate in the PTV. Results: The effect of the density of the materials surrounding the MammoSite balloon containing 0% contrast material on the calculated dose rate at different radial distances in the PTV was demonstrated. Within the PTV, the ratio of the calculated dose rate for the AFCP and the semi-infinite water phantom for the point closest to the breast-air interface (90 deg.) is less than that for the point closest to the breast-lung interface (270 deg.) by 11.4% and 4% for the HDR sources of Yb-169 and Ir-192, respectively. When contrast material was introduced into the 2 cm radius MammoSite balloon at varying concentrations, (5%, 10%, 15%, and 20%), the dose rate in the AFCP at 3.0 cm radial distance at 90 deg. was decreased by as much as 14.8% and 6.2% for Yb-169 and Ir-192, respectively, when compared to that of the semi-infinite water phantom with contrast concentrations of 5%, 10%, 15%, and 20%, respectively. Conclusions: Commercially available software used to calculate dose rate in the PTV of a MammoSite balloon needs to account for patient anatomy and density of surrounding materials in the dosimetry analyses in order to avoid patient underdose.

  12. Defining the “Hostile Pelvis” for Intensity Modulated Radiation Therapy: The Impact of Anatomic Variations in Pelvic Dimensions on Dose Delivered to Target Volumes and Organs at Risk in Patients With High-Risk Prostate Cancer Treated With Whole Pelvic Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yirmibeşoğlu Erkal, Eda, E-mail: eyirmibesoglu@yahoo.com [Department of Radiation Oncology, Kocaeli University Faculty of Medicine, Kocaeli (Turkey); Karabey, Sinan [Department of Radiation Oncology, Kocaeli University Faculty of Medicine, Kocaeli (Turkey); Karabey, Ayşegül [Department of Radiation Oncology, Kocaeli State Hospital, Kocaeli (Turkey); Hayran, Mutlu [Department of Preventive Oncology, Hacettepe University Cancer Institute, Ankara (Turkey); Erkal, Haldun Şükrü [Department of Radiation Oncology, Sakarya University Faculty of Medicine, Sakarya (Turkey)

    2015-07-15

    Purpose: The aim of this study was to evaluate the impact of variations in pelvic dimensions on the dose delivered to the target volumes and the organs at risk (OARs) in patients with high-risk prostate cancer (PCa) to be treated with whole pelvic radiation therapy (WPRT) in an attempt to define the hostile pelvis in terms of intensity modulated radiation therapy (IMRT). Methods and Materials: In 45 men with high-risk PCa to be treated with WPRT, the target volumes and the OARs were delineated, the dose constraints for the OARs were defined, and treatment plans were generated according to the Radiation Therapy Oncology Group 0924 protocol. Six dimensions to reflect the depth, width, and height of the bony pelvis were measured, and 2 indexes were calculated from the planning computed tomographic scans. The minimum dose (D{sub min}), maximum dose (D{sub max}), and mean dose (D{sub mean}) for the target volumes and OARs and the partial volumes of each of these structures receiving a specified dose (V{sub D}) were calculated from the dose-volume histograms (DVHs). The data from the DVHs were correlated with the pelvic dimensions and indexes. Results: According to an overall hostility score (OHS) calculation, 25 patients were grouped as having a hospitable pelvis and 20 as having a hostile pelvis. Regarding the OHS grouping, the DVHs for the bladder, bowel bag, left femoral head, and right femoral head differed in favor of the hospitable pelvis group, and the DVHs for the rectum differed for a range of lower doses in favor of the hospitable pelvis group. Conclusions: Pelvimetry might be used as a guide to define the challenging anatomy or the hostile pelvis in terms of treatment planning for IMRT in patients with high-risk PCa to be treated with WPRT.

  13. Optimal margins between clinical target volume (CTV) and planning target volume (PTV)

    OpenAIRE

    Hjulfors, Emmelie Maria

    2011-01-01

    The purpose of this study was to estimate the CTV-PTV margin required for prostate and head and neck cancer treatments at the radiotherapy departments of Karolinska University Hospital.    Portal image data from patients treated at the radiotherapy departments during the period of 2009-2011 was used to estimate the set-up displacements for each treatment area. By using the acquired images the magnitude of the systematic, i.e. preparatory, and random, i.e. execution, error was determined in th...

  14. Renormalized Volume

    CERN Document Server

    Gover, A Rod

    2016-01-01

    For any conformally compact manifold with hypersurface boundary we define a canonical renormalized volume functional and compute an explicit, holographic formula for the corresponding anomaly. For the special case of asymptotically Einstein manifolds, our method recovers the known results. The anomaly does not depend on any particular choice of regulator, but the coefficients of divergences do. We give explicit formulae for these divergences valid for any choice of regulating hypersurface; these should be relevant to recent studies of quantum corrections to entanglement entropies. The anomaly is expressed as a conformally invariant integral of a local Q-curvature that generalizes the Branson Q-curvature by including data of the embedding. In each dimension this canonically defines a higher dimensional generalization of the Willmore energy/rigid string action. We show that the variation of these energy functionals is exactly the obstruction to solving a singular Yamabe type problem with boundary data along the...

  15. Multi-scenario based robust intensity-modulated proton therapy (IMPT) plans can account for set-up errors more effectively in terms of normal tissue sparing than planning target volume (PTV) based intensity-modulated photon plans in the head and neck region

    International Nuclear Information System (INIS)

    In a previous report, we compared the conformity of robust intensity-modulated proton therapy (IMPT) plans with that of helical tomotherapy plans for re-irradiations of head and neck carcinomas using a fixed set-up error of 2 mm. Here, we varied the maximum set-up errors between 0 and 5 mm and compared the robust IMPT-plans with planning target volume (PTV) based intensity-modulated photon therapy (IMRT). Seven patients were treated with a PTV-based tomotherapy plan. Set-up margins of 0, 2, and 5 mm were subtracted from the PTV to generate target volumes (TV) TV0mm, TV2mm, and TV5mm, for which robust IMPT-plans were created assuming range uncertainties of ±3.5% and using worst case optimization assuming set-up errors of 0, 2, and 5 mm, respectively. Robust optimization makes use of the feature that set-up errors in beam direction alone do not affect the distal and proximal margin for that beam. With increasing set-up errors, the body volumes that were exposed to a selected minimum dose level between 20% and 95% of the prescribed dose decreased. In IMPT-plans with 0 mm set-up error, the exposed body volumes were on average 6.2% ± 0.9% larger than for IMPT-plans with 2 mm set-up error, independent of the considered dose level (p < 0.0001, F-test). In IMPT-plans accounting for 5 mm set-up error, the exposed body volumes were by 11.9% ± 0.8% smaller than for IMPT-plans with 2 mm set-up error at a fixed minimum dose (p < 0.0001, F-test). This set-up error dependence of the normal tissue exposure around the TV in robust IMPT-plans corresponding to the same IMRT-plan led to a decrease in the mean dose to the temporal lobes and the cerebellum, and in the D2% of the brain stem or spinal cord with increasing set-up errors considered during robust IMPT-planning. For recurrent head and neck cancer, robust IMPT-plan optimization led to a decrease in normal tissue exposure with increasing set-up error for target volumes corresponding to the same PTV

  16. CERN: Fixed target targets

    International Nuclear Information System (INIS)

    Full text: While the immediate priority of CERN's research programme is to exploit to the full the world's largest accelerator, the LEP electron-positron collider and its concomitant LEP200 energy upgrade (January, page 1), CERN is also mindful of its long tradition of diversified research. Away from LEP and preparations for the LHC proton-proton collider to be built above LEP in the same 27-kilometre tunnel, CERN is also preparing for a new generation of heavy ion experiments using a new source, providing heavier ions (April 1992, page 8), with first physics expected next year. CERN's smallest accelerator, the LEAR Low Energy Antiproton Ring continues to cover a wide range of research topics, and saw a record number of hours of operation in 1992. The new ISOLDE on-line isotope separator was inaugurated last year (July, page 5) and physics is already underway. The remaining effort concentrates around fixed target experiments at the SPS synchrotron, which formed the main thrust of CERN's research during the late 1970s. With the SPS and LEAR now approaching middle age, their research future was extensively studied last year. Broadly, a vigorous SPS programme looks assured until at least the end of 1995. Decisions for the longer term future of the West Experimental Area of the SPS will have to take into account the heavy demand for test beams from work towards experiments at big colliders, both at CERN and elsewhere. The North Experimental Area is the scene of larger experiments with longer lead times. Several more years of LEAR exploitation are already in the pipeline, but for the longer term, the ambitious Superlear project for a superconducting ring (January 1992, page 7) did not catch on. Neutrino physics has a long tradition at CERN, and this continues with the preparations for two major projects, the Chorus and Nomad experiments (November 1991, page 7), to start next year in the West Area. Delicate neutrino oscillation effects could become

  17. Sputter target

    Science.gov (United States)

    Gates, Willard G.; Hale, Gerald J.

    1980-01-01

    The disclosure relates to an improved sputter target for use in the deposition of hard coatings. An exemplary target is given wherein titanium diboride is brazed to a tantalum backing plate using a gold-palladium-nickel braze alloy.

  18. Impact of planning target volume (PTV) on the late toxicity and on survival without biochemical relapse among patients suffering from a prostate cancer and treated by intensity-modulated conformational irradiation guided by three-dimensional echography; Impact du volume cible previsionnel (PTV) sur la toxicite tardive et la survie sans rechute biochimique chez des patients atteints d'un cancer de la prostate traite par irradiation conformationnalle avec modulation d'intensite guidee par echographie tridimensionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Mirjolet, C.; Crehange, G.; Gauthier, M.; Azelie, C.; Martin, E.; Truc, G.; Peignaux, K.; Bonnetain, F.; Naudy, S.; Maingon, P. [Centre Georges Francois Leclerc, 21 - Dijon (France)

    2010-10-15

    As several dosimetric studies demonstrated a theoretical benefit of the image-guided and intensity-modulated conformational radiotherapy (IMRT) to reduce the planning target volume (PTV) margins and irradiated healthy tissues, the authors report and discuss data obtained on 170 men suffering from a prostate cancer and treated by IMRT with a daily repositioning performed using a three-dimensional echography. Patients have been classified in two groups with respect to the margin value. Toxicity has been assessed and survival without biochemical progress has been computed. Few grade 2 genital-urinary effects have been observed. Only patients having a Gleason score greater than 7 or suffering from diabetes have a lower survival rate without biochemical advance. Short communication

  19. Influence of CT/MRI Fusion Image on Target Volume and 3-D Conformal Radiotherapy in Non-small Cell Lung Cancer with Brain Metastasis%CT/MRI诊断影像融合对非小细胞肺癌脑转移瘤靶区及三维适形治疗影响

    Institute of Scientific and Technical Information of China (English)

    杨金山; 魏永兵; 侯超; 李静; 朱瑞霞

    2014-01-01

    目的:比较CT图像和CT/MRI融合图像来源的肺癌脑转移肿瘤靶区,评价CT/MRI融合靶区容积应用于三维适形放射治疗时,对治疗剂量的影响。方法:将20例非小细胞肺癌脑转移患者的增强CT和MRI扫描的图像传送至图像处理工作站,在CT和CT/MRI融合图像上分别勾画GTV和周围重要的器官。每个病例分别在CT图像和CT/MRI融合图像都做1个三维适形放射治疗计划。肿瘤的处方剂量为60 Gy,比较2个治疗计划中肿瘤靶区的95%容积(D95)受照平均剂量、周围正常组织的5%容积(D5)受照平均剂量。结果:CT/MRI融合图像上的肿瘤靶区平均比CT上的肿瘤靶区大21.32%。用CT上勾画的靶区有一部分肿瘤处于低剂量区,CT/MRI融合图像上的靶区D95剂量分布较好,但在周围重要器官的剂量分布较高。结论:CT/MRI融合图像有助于靶区的确定,在三维适形放射治疗计划上的肿瘤靶区剂量分布足够,能提高靶区勾画的准确性,更利于精确放疗的实施。%Objective:To compare the CT images and CT/MRI images fusion sources of lung cancer with brain metastasis tumor target,and to evaluae the effects of dose for treatment on target volume CT/MRI fusion for three-dimensional conformal radiotherapy. Method:The enhancement CT and MRI scan image of 20 patients with brain metastases from non-small cell lung cancer was transfer to image processing workstation,GTV and surrounding vital organs on CT and CT/MRI images fusion was delineated respectively. A three-dimensional conformal radiotherapy plan was done in CT images and CT/MRI fusion images of ach case. Tumor prescription dose was 60 Gy. Compared the average dose of the 95%volume(D95)tumor target,the average dose of the 5%of the normal tissue around of the two treatment plans. Result:The tumor targets of the CT/MRI images fusion was greater than those of the CT tumor targets on average 21.32%. A part of the tumor was

  20. CTVision系统在分析鼻咽癌放疗过程靶区体积及其剂量学变化规律中的应用%Application of CTVision System in Analysis of the Change Law of the Target Volume and Dose for Nasopharyngeal Carcinoma in the Course of Radiotherapy

    Institute of Scientific and Technical Information of China (English)

    甘晓根; 徐子海; 廖福锡

    2015-01-01

    Objective To study the effectiveness of application of CTVision system in analysis of the change law of the target volume and dose for nasopharyngeal carcinoma in the course of radiotherapy. Methods Image-guided IMRT (Intensity-Modulated Radiation Therapy) was performed in 10 patients with nasopharyngeal carcinoma by using CTVision system to analyze the change law of the volume of target area and parotids. Then, the CT images were transmitted back to the TPS (Treatment Planning System) for recalculation and analysis of the dose for organs at risk.Results The volume of target area as well as the volume of bilateral parotids was diminishing with the progress of radiotherapy. And the volume of target area as well as the volume of right-sided parotids revealed obvious differences in the 4th week of radiotherapy from the pre-treatment volume. The volume of left-sided parotids revealed obvious differences in the 5th week of radiotherapy from the pre-treatment volume. Meanwhile, the radiation dose received by bilateral parotids increased gradually with the shrinkage of the volume, and was positively associated with the shrinkage degree (Right-sided parotids:r=0.471,P=0.036; Left-sided parotids:r=0.578,P=0.008).Conclusion For nasopharyngeal carcinoma patients who were experiencing IMRT, the volume of target area and parotids was shrinking with the progress of radiotherapy, leading to the increasing of the dose for organs. In view of this, it was suggested to redraw the outline of the target area and redesign the radiotherapy plan in the 4th to 5th week in of IMRT, which would improve the local control rate of nasopharyngeal carcinoma and reduce the side effects of radiation.%目的:探讨CTVision系统在分析鼻咽癌放疗过程靶区体积及其剂量学变化规律中的应用价值。方法采用CTVision系统对10例鼻咽癌患者进行图像引导调强放疗,分析鼻咽癌靶区及腮腺体积在放疗过程中的变化规律。并将采集到的CT图像传

  1. Is it always possible to respect dose constraints for target volumes and organs at risk within the frame of breast radiotherapy after conservative treatment?; Le respect des contraintes de dose aux volumes cibles et aux organes a risque est-il toujours possible dans le cadre d'une radiotherapie du sein apres traitement conservateur?

    Energy Technology Data Exchange (ETDEWEB)

    Renoult, F.; Faivre, J.C.; Charra Brunaud, C.; Tournier-Rangeard, L.; Lostette, J.; Huger, S.; Marchesi, V.; Peiffert, D.; Marchal, C. [Centre Alexis-Vautrin, 54 - Nancy (France); Xemard, S. [Centre hospitalier Jean-Monnet, 88 - Epinal (France)

    2010-10-15

    The use of three-dimensional breast radiotherapy after a conservative treatment allowed cardiotoxicity as well as the dose delivered to lungs to be significantly reduced. However several bibliographic references give different dose constraints. Based on the constraints given by the Oncological radiotherapy French Society (SFRO), the authors analysed whether these recommendations could be actually respected within a daily practice. Based on a sample of 91 patients, the authors collected the following data: mammary gland volumes receiving respectively 95 and 107% of the dose before the boost calculation, heart and pulmonary volumes receiving different dose levels. Coverage constraints are indicated. It appears that the present technique does not allow the constraints to be respected in a majority of cases. Short communication

  2. Antiproton Target

    CERN Multimedia

    1980-01-01

    Antiproton target used for the AA (antiproton accumulator). The first type of antiproton production target used from 1980 to 1982 comprised a rod of copper 3mm diameter and 120mm long embedded in a graphite cylinder that was itself pressed into a finned aluminium container. This assembly was air-cooled and it was used in conjunction with the Van der Meer magnetic horn. In 1983 Fermilab provided us with lithium lenses to replace the horn with a view to increasing the antiproton yield by about 30%. These lenses needed a much shorter target made of heavy metal - iridium was chosen for this purpose. The 50 mm iridium rod was housed in an extension to the original finned target container so that it could be brought very close to the entrance to the lithium lens. Picture 1 shows this target assembly and Picture 2 shows it mounted together with the lithium lens. These target containers had a short lifetime due to a combination of beam heating and radiation damage. This led to the design of the water-cooled target in...

  3. Liquid Hydrogen Target for the COMPASS experiment

    CERN Document Server

    Bremer, J; Duday-Chanat, L; Geyer, R; Mallot, G K; Pirotte, O; Vullierme, B

    2014-01-01

    A liquid hydrogen target has been developed for the COMPASS experiment at CERN. The target has a diameter of 40 mm and a length of 2.5 meter, creating an active volume of about 3 liter of liquid hydrogen. The cylindrical part of the target wall is formed by a Kapton® foil strip, wound and glued to a thickness of 0.125 mm. The Kapton® foil is used to minimize the energy loss of the particles, scattered or created within the target volume, crossing the target boundary. The two end-caps enclosing the target volume have been fabricated from Mylar®. The system is cooled with a 30 W at 20 K cryocooler, delivering the cooling capacity for the cool-down as well as for the continuous operation of the system.

  4. CT与MRI图像融合对脑转移瘤三维适形放疗靶区的影响%The influence of target volume by CT/MRI image fusion on brain metastasis's three-dimensional conformal radiotherapy

    Institute of Scientific and Technical Information of China (English)

    陈苏玮; 袁锋; 林志仁; 王伟锋

    2012-01-01

    Objective To improve the accuracy of delineating three-dimensional conformal radiotherapy target volume by comparing the difference between computed tomography(CT)/magnetic resonance imaging (MRI) image fusion on brain metastasis area and CT's target area. Methods CT's images and MRI's images collected from 25 cases with brain metastasis in the same period were transmitted to image processing workstation and fused into CT/MRI images, and then 41 pairs of gross tumor volume (GTV) were delineated in CT and CT/MRI, and finally difference was compared between the two group. Results The value of GTVCT in 41 pairs from 25 cases was (31.75±9.93) cm3 and in GTVCT/MRI was (28.92±8.25) cm3. Among 41 control groups, the number of the accuracy of GTVCT lower than that of GTVCT/MRI was 18, GTCCT higher than that of GTVCT/MRI was 23. Conclusion The improving accuracy of brain metastasis's target volume sketched by CT/MRI image fusion is more suitable for three-dimensional conformal radiotherapy.%目的 研究CT与MRI图像融合的脑转移瘤靶区与CT图像靶区的不同,提高三维适形放疗靶区勾画的准确性.方法 同期采集25例脑转移瘤患者的CT和MRI图像,传送至图像处理工作站融合成CT/MRI图像,分别在CT及CT/MRI融合图像勾画41组GTV,比较两种图像勾画的GTV的差别.结果 25例患者共41组靶区的GTVcr为(31.75±9.93)cm3,GTVCT/MRI为(28.92±8.25)cm3.41个对照组中,GTVCr <GTVCT/MRI为18个,GTVCT >GTVCT/MRI为23个.结论 采用CT/MRI融合后图像勾画的脑转移瘤靶区精确度提高,更适合于三维立体适形放疗.

  5. Targeted multi-pinhole SPECT

    NARCIS (Netherlands)

    Branderhorst, W.; Vastenhouw, B.; Van der Have, F.; Blezer, E.L.A.; Bleeker, W.K.; Beekman, F.J.

    2010-01-01

    Purpose: Small-animal single photon emission computed tomography (SPECT) with focused multi-pinhole collimation geometries allows scanning modes in which large amounts of photons can be collected from specific volumes of interest. Here we present new tools that improve targeted imaging of specific o

  6. Estimation of daily interfractional larynx residual setup error after isocentric alignment for head and neck radiotherapy: Quality-assurance implications for target volume and organ-at-risk margination using daily CT-on-rails imaging

    Science.gov (United States)

    Baron, Charles A.; Awan, Musaddiq J.; Mohamed, Abdallah S. R.; Akel, Imad; Rosenthal, David I.; Gunn, G. Brandon; Garden, Adam S.; Dyer, Brandon A.; Court, Laurence; Sevak, Parag R; Kocak-Uzel, Esengul; Fuller, Clifton D.

    2016-01-01

    Larynx may alternatively serve as a target or organ-at-risk (OAR) in head and neck cancer (HNC) image-guided radiotherapy (IGRT). The objective of this study was to estimate IGRT parameters required for larynx positional error independent of isocentric alignment and suggest population–based compensatory margins. Ten HNC patients receiving radiotherapy (RT) with daily CT-on-rails imaging were assessed. Seven landmark points were placed on each daily scan. Taking the most superior anterior point of the C5 vertebra as a reference isocenter for each scan, residual displacement vectors to the other 6 points were calculated post-isocentric alignment. Subsequently, using the first scan as a reference, the magnitude of vector differences for all 6 points for all scans over the course of treatment were calculated. Residual systematic and random error, and the necessary compensatory CTV-to-PTV and OAR-to-PRV margins were calculated, using both observational cohort data and a bootstrap-resampled population estimator. The grand mean displacements for all anatomical points was 5.07mm, with mean systematic error of 1.1mm and mean random setup error of 2.63mm, while bootstrapped POIs grand mean displacement was 5.09mm, with mean systematic error of 1.23mm and mean random setup error of 2.61mm. Required margin for CTV-PTV expansion was 4.6mm for all cohort points, while the bootstrap estimator of the equivalent margin was 4.9mm. The calculated OAR-to-PRV expansion for the observed residual set-up error was 2.7mm, and bootstrap estimated expansion of 2.9mm. We conclude that the interfractional larynx setup error is a significant source of RT set-up/delivery error in HNC both when the larynx is considered as a CTV or OAR. We estimate the need for a uniform expansion of 5mm to compensate for set up error if the larynx is a target or 3mm if the larynx is an OAR when using a non-laryngeal bony isocenter. PMID:25679151

  7. ICF target positioning robot system

    International Nuclear Information System (INIS)

    Based on the function analysis of target positioner for inertial confinement fusion, a kind of ICF target positioning robot system is designed to realize the adjustment and the alignment of a target. The robot system includes a target storage sub-system, a target exchange subsystem, a target transport subsystem and a 6-degree of freedom precision parallel robot subsystem, the structure and principle of every subsystem are dissertated. The system realizes micro scale position by parallel structure which is in the front of the system, and has the advantages of low mass, high stiffness, small cone angle, small volume and high precision. The robot system can position a target into a very small micro scale scope around the center of the target chamber whose diameter is several meters, the precision of the position reaches micro scale. Motion parameter of the positioning robot system has been tested. Experiment proves that the robot system has realized precision target position and target exchange on the condition of vacuum. (authors)

  8. Targeted Learning

    CERN Document Server

    van der Laan, Mark J

    2011-01-01

    The statistics profession is at a unique point in history. The need for valid statistical tools is greater than ever; data sets are massive, often measuring hundreds of thousands of measurements for a single subject. The field is ready to move towards clear objective benchmarks under which tools can be evaluated. Targeted learning allows (1) the full generalization and utilization of cross-validation as an estimator selection tool so that the subjective choices made by humans are now made by the machine, and (2) targeting the fitting of the probability distribution of the data toward the targe

  9. Ovarian volume throughout life

    DEFF Research Database (Denmark)

    Kelsey, Thomas W; Dodwell, Sarah K; Wilkinson, A Graham;

    2013-01-01

    cancer. To date there is no normative model of ovarian volume throughout life. By searching the published literature for ovarian volume in healthy females, and using our own data from multiple sources (combined n=59,994) we have generated and robustly validated the first model of ovarian volume from...... to about 2.8 mL (95% CI 2.7-2.9 mL) at the menopause and smaller volumes thereafter. Our model allows us to generate normal values and ranges for ovarian volume throughout life. This is the first validated normative model of ovarian volume from conception to old age; it will be of use in the diagnosis...

  10. B-mode ultrasound for defining planning target volume in intensity-modulated radiotherapy for prostate cancer%超声图像引导定义前列腺癌调强放疗的计划靶区

    Institute of Scientific and Technical Information of China (English)

    任陈; 刘佳宾; 袁亚维; 陈龙华; 刘英

    2011-01-01

    目的 分析超声图像引导摆位系统(B mode acquisition and targeting,BAT)辅助前列腺癌调强放疗时等中心摆位误差,定义无影像引导下前列腺癌调强放疗计划靶区(PTV)的边界.材料和方法 选择10例前列腺癌患者每日应用BAT弓导摆位进行调强放疗,记录每次等中心前后(AP)、左右和头脚方向上移位的偏差,共255次.采用Kolmogorov-Smimov方法分析检验所获得的数据.结果 BAT验证后等中心移位在左右方向为(3.56 ±2.71)mm,前后方向(4.08±3.99) mm,头脚方向(3.20±2.92)mm.各个方向上的偏差符合正态分布(RL P=0.806,AP P=0.0.061,SIP=0.106).在没有图像引导前列腺癌调强放疗摆位的情况下,为满足95%的等剂量曲线覆盖90%患者的CTV,PTV边界需在左右方向向右扩大8.97 mm,向左1.87 mm,前后方向向前需扩大12.05 mm,向后3.91 mm,头脚方向向头侧扩大9.06 mm,向脚侧扩大2.66 mm.结论 超声图像引导摆位操作简便,无辐射,系统误差小,可实时纠正.%Objective To investigate the prevalence of cardiovascular diseases (CVD) in patients with systemic lupus erythematosus (SLE) and estimate the associated risk factors for CVD. Methods This cross-sectional study was conducted in 879 SLE patients treated in our hospital between March, 2006 and March, 2011. The demographic data and the clinical data including SLE duration, therapeutic regimen, renal pathological data, estimated glomerular filtration rate (eGFR), SLE Disease Activity Index (SLEDAI), and associated biochemical parameters were analyzed. Cardiovascular ultrasound was used for detecting and analyzing the cardiovascular structural and functional abnormalities. Results Eighty-five cases of CVD were found in the 879 SLE cases (9.7%). After age stratification, CVD was identified in 5.8%, 9.0%, 14.0% and 20.0% in SLE patients aged ≤19, 20-39, 40-59 and ≥60 years, respectively, showing a tendency to increase with age (P=0.002). The prevalence of CVD

  11. Volume Regulation in Epithelia

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Hoffmann, Else Kay

    2016-01-01

    We review studies on regulatory volume decrease (RVD) and regulatory volume increase (RVI) of major ion and water transporting vertebrate epithelia. The rate of RVD and RVI is faster in cells of high osmotic permeability like amphibian gallbladder and mammalian proximal tubule as compared...... to amphibian skin and mammalian cortical collecting tubule of low and intermediate osmotic permeability. Crosstalk between entrance and exit mechanisms interferes with volume regulation both at aniso-osmotic and iso-osmotic volume perturbations. It has been proposed that cell volume regulation is an intrinsic...

  12. Follicular penetration and targeting.

    Science.gov (United States)

    Lademann, Jürgen; Otberg, Nina; Jacobi, Ute; Hoffman, Robert M; Blume-Peytavi, Ulrike

    2005-12-01

    In the past, intercellular penetration was assumed to be the most important penetration pathway of topically applied substances. First hints that follicular penetration needs to be taken into consideration were confirmed by recent investigations, presented during the workshop "Follicular Penetration and Targeting" at the 4th Intercontinental Meeting of Hair Research Societies", in Berlin 2004. Hair follicles represent an efficient reservoir for the penetration of topically applied substances with subsequent targeting of distinct cell populations, e.g., nestin-expressing follicular bulge cells. The volume of this reservoir can be determined by differential stripping technology. The follicular penetration processes are significantly influenced by the state of the follicular infundibulum; recent experimental investigations could demonstrate that it is essential to distinguish between open and closed hair follicles. Topically applied substances can only penetrate into open hair follicle. Knowledge of follicular penetration is of high clinical relevance for functional targeting of distinct follicular regions. Human hair follicles show a hair-cycle-dependent variation of the dense neuronal and vascular network. Moreover, during hair follicle cycling with initiation of anagen, newly formed vessels occur. Thus, the potential of nestin-expressing hair follicle stem cells to form neurons and blood vessels was investigated.

  13. IUCF liquid hydrogen target system

    International Nuclear Information System (INIS)

    A liquid hydrogen or deuterium target system is described for use with intermediate energy light ion beams at IUCF. In its present use as a production target for polarized neutrons, the target cell is mounted within the beamline. Thus, certain safety features are required which prevent a possible hydrogen explosion inside the beamline or the cyclotron. These safety devices include an acoustical delay line which slows the hydrogen gas shock wave and a fast valve which closes before any large volume of escaping gas reaches it. Other safety interlocks to reduce the chances of target cell breakage and to quickly shut off ignition sources are discussed. A device involving a variable heat load which is coupled directly to the cryocondenser and is used to continually monitor and stabilize the pressure and temperature of the liquid hydrogen is described here

  14. 基于3D-CT与4D-CT勾画保留乳房手术后全乳靶区的比较研究%Comparison study of clinical target volumes of whole breast after breast-conserving surgery based on three-dimensional CT and four-dimensional CT images

    Institute of Scientific and Technical Information of China (English)

    王素贞; 李建彬; 张英杰; 王玮; 李奉祥; 徐敏; 邵倩; 范廷勇; 刘同海

    2012-01-01

    Objective To study the differences of the clinical target volume ( CTV) based on three-dimensional CT (3D-CT) and four-dimensional CT (4D-CT) of the whole breast after breast-conserving surgery. Methods Thirteen patients after breast-conserving surgery underwent 3D-CT simulation scans followed by 4D-CT simulation scans of the thorax during free breathing. During 4D-CT scanning, real-time position management ( RPM ) system simultaneously recorded the respiratory signals. The CT images with respiratory signal data were reconstructed and sorted into 10 phase groups in a respiratory cycle. Data sets for 3D-CT and 4D-CT scans were then transferred to Eclipse treatment planning software. The 4D-CT image of the end-inhalation phase (TO) served as a background and the other nine phases ( T10 , T20 , T30··· T90 ) , maximum intensity projection ( MIP ) image and 3D-CT image were registered. The CTV were manually delineated on the registered images of the 3D-CT, TO, middle-exhalation (T20) , end-exhalation (T50) , MIP images based on the TO of 4D-CT by a radiation oncologist at two different times. Then the CTV3D , CTV0 , CTV10··· CTVMIP were delineated and defined on the 3D-CT, TO, T10···MIP images based on the TO images of 4D-CT by the same radiation oncologist. All the CTVs ( CTV0 , CTV10 , CTV10··· CTV90) delineated on the 10 phases of the 4D-CT images were fused into an internal clinical target volume (ICTV). The TO , T20 , T50 , MIP images were selected from the CTVs of the 4D-CT to compare with the 3D-CT image. The differences of the targets delineated on the same images by the same radiation oncologist at different times were compared. The volumes of the CTVS, the matching index ( MI) and the degree of inclusion ( DI) were compared respectively. Results There was no difference in the CTV delineated by the same oncologist no matter based on 3D-CT or 4D-CT( P>0. 050). The CTVs volumes of ten phases in 4D-CT were not impacted by respiratory movement( P>0. 05

  15. Calf muscle volume estimates: Implications for Botulinum toxin treatment?

    DEFF Research Database (Denmark)

    Bandholm, Thomas Quaade; Sonne-Holm, Stig; Thomsen, Carsten;

    2007-01-01

    An optimal botulinum toxin dose may be related to the volume of the targeted muscle. We investigated the suitability of using ultrasound and anthropometry to estimate gastrocnemius and soleus muscle volume. Gastrocnemius and soleus muscle thickness was measured in 11 cadaveric human legs, using...

  16. Liquid hydrogen target cooled by circulating helium

    International Nuclear Information System (INIS)

    Structure and characteristics of a liquid hydrogen target, where hydrogen is liquefied with liquid helium flow using evaporation heat of liquid helium and vapour cold, are described. Good thermal insulation of liquid helium supply line permits to remove out of the target the most volumetric and heavy component - helium tank - and to supply liquid helium along spreaded pipeline from the Dewar helium flask. It results in considerable reduction of dimensions and weight, the structure simplification and work facilitation with the target. The target having a working volume of 400 mm length and 60 mm diameter was tested. Vacuum casing of the working volume was made of foam plastic, heat flow to the working volume is equal to 1.5 W. Achieving mode of operation including structure cooling and hydrogen liquefaction took approximately 3 h, liquid helium flow rate for liquefaction of 1 l hydrogen is 2.7 l. Liquid helium flow rate in the mode of operation was equal to 0.7 l/h, i.e. target operation period without adding liquid helium to the Dewar flask is 4-5 days. The target described is notable for simplicity in fabrication, reliability in operation and is very suitable for using in experiment as compared to existing targets with hydrogen liquefaction with liquid helium. Unit structure of the target enables to easily change its configuration relative to problems of concrete physical experiment

  17. Volume difference inequalities

    OpenAIRE

    Giannopoulos, Apostolos; Koldobsky, Alexander

    2016-01-01

    We prove several inequalities estimating the distance between volumes of two bodies in terms of the maximal or minimal difference between areas of sections or projections of these bodies. We also provide extensions in which volume is replaced by an arbitrary measure.

  18. The study of clinical target volume motion of radical intensity-modulated radiotherapy for non-surgical cer-vical cancer patients by cone beam computed tomography%锥形束CT评价根治性宫颈癌调强放疗患者肿瘤临床靶区运动度的研究∗

    Institute of Scientific and Technical Information of China (English)

    丁嘉佩; 袁君; 朱红; 吴苏日娜; 严思奇; 马觉

    2016-01-01

    Objective To investigate the motion of clinical target volume(CTV)by using cone beam computed tomography ( CBCT) on linear accelerator and to determine a internal margin( IM) value for the internal target volume( ITV) during intensity-modula-ted radiotherapy( IMRT) for non-surgical cervical cancer. Methods One hundred and forty CBCT images from 20 non-surgical cervical cancer patients who underwent radical IMRT from Dec 2013 to Oct 2014 were selected for this study. The deformation and displacement between the simulation CT and CBCTs were measured. Results The volume reductions of CTV1 between the simulation CT and CBCTs were(33. 56±22. 52) cm3(range from 1. 04-110. 22 cm3) and the percentages of the volume reductions were(10. 19±6. 32)%(range from 0. 37%-32. 01%). The motion between the simulation CT and CBCTs were(1. 19±0. 82)cm,(0. 80±0. 55)cm,(0. 16±0. 25)cm,(0. 23± 0. 29) cm, ( 0. 27 ± 0. 42) cm, ( 0. 18 ± 0. 24) cm and ( 0. 78 ± 1. 09) cm in the anterio-posterior directions of uterus, anterio-posterior directions of cervix, superior directions of uterus, lateral directions of the same side, the opposite side of the bottom of uterus, respective-ly. If the IM was set less than 2 cm, the CTV of 85% CBCTs could be covered completely. 95% patients showed greater uterus motions than cervical motions in all directions. The motion of CTV1 had great individual difference. Conclusion The strategies of target outline for different IM size at three dimensional direction obtained by CBCT and different IM size of uterus and cervix, in combination with indi-vidualized image guided radiotherapy may be a good clinical form for realizing precise radiotherapy in cervical cancer.%目的:探讨采用锥形束 CT ( CBCT )评价未手术宫颈癌患者适形调强放射治疗( IMRT )中肿瘤临床靶区(CTV)内界值的移动度,以期为未手术宫颈癌根治性放疗患者肿瘤CTV-ITV扩界值(IM)的设定提供参考。方法收集2013年12

  19. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G. [David Geffen School of Medicine at UCLA, Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, Los Angeles, CA (United States); Strange, Charlie [Medical University of South Carolina, Department of Pulmonary and Critical Care Medicine, Columbia, SC (United States); Tashkin, Donald P. [David Geffen School of Medicine at UCLA, Division of Pulmonary and Critical Care Medicine, Los Angeles, CA (United States)

    2012-07-15

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  20. Bronchoscopic lung volume reduction

    Directory of Open Access Journals (Sweden)

    M. I. Polkey

    2006-12-01

    Full Text Available Surgical lung volume reduction can improve exercise performance and forced expiratory volume in one second in patients with emphysema. However, the procedure is associated with a 5% mortality rate and a nonresponse rate of 25%. Accordingly, interest has focused on alternative ways of reducing lung volume. Two principle approaches are used: collapse of the diseased area using blockers placed endobronchially and the creation of extrapulmonary pathways. Preliminary data from the former approach suggest that it can be successful and that the magnitude of success is related to reduction in dynamic hyperinflation.

  1. Towards the Amplituhedron Volume

    CERN Document Server

    Ferro, Livia; Orta, Andrea; Parisi, Matteo

    2015-01-01

    It has been recently conjectured that scattering amplitudes in planar N=4 super Yang-Mills are given by the volume of the (dual) amplituhedron. In this paper we show some interesting connections between the tree-level amplituhedron and a special class of differential equations. In particular we demonstrate how the amplituhedron volume for NMHV amplitudes is determined by these differential equations. The new formulation allows for a straightforward geometric description, without any reference to triangulations. Finally we discuss possible implications for volumes related to generic N^kMHV amplitudes.

  2. LLE Review Quarterly Report (April-June 1985). Volume 23

    Energy Technology Data Exchange (ETDEWEB)

    Skupsky, S. [Univ. of Rochester, NY (United States)

    1985-06-01

    This volume of the LLE Review contains articles on the fully UV converted OMEGA laser system, mass-ablation rate experiments, reactor-size target designs, plasma processes in the target corona, degradation in optical performance of dielectric thin films, and the National Laser Users Facility activities for April-June 1985.

  3. Live ultrasound volume reconstruction using scout scanning

    Science.gov (United States)

    Meyer, Amelie; Lasso, Andras; Ungi, Tamas; Fichtinger, Gabor

    2015-03-01

    Ultrasound-guided interventions often necessitate scanning of deep-seated anatomical structures that may be hard to visualize. Visualization can be improved using reconstructed 3D ultrasound volumes. High-resolution 3D reconstruction of a large area during clinical interventions is challenging if the region of interest is unknown. We propose a two-stage scanning method allowing the user to perform quick low-resolution scouting followed by high-resolution live volume reconstruction. Scout scanning is accomplished by stacking 2D tracked ultrasound images into a low-resolution volume. Then, within a region of interest defined in the scout scan, live volume reconstruction can be performed by continuous scanning until sufficient image density is achieved. We implemented the workflow as a module of the open-source 3D Slicer application, within the SlicerIGT extension and building on the PLUS toolkit. Scout scanning is performed in a few seconds using 3 mm spacing to allow region of interest definition. Live reconstruction parameters are set to provide good image quality (0.5 mm spacing, hole filling enabled) and feedback is given during live scanning by regularly updated display of the reconstructed volume. Use of scout scanning may allow the physician to identify anatomical structures. Subsequent live volume reconstruction in a region of interest may assist in procedures such as targeting needle interventions or estimating brain shift during surgery.

  4. Environmental chemistry: Volume A

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T.F.

    1999-08-01

    This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

  5. Cooking the volumes

    OpenAIRE

    Sparavigna, Amelia Carolina

    2012-01-01

    Cooking possesses a system of units of measurement, that includes measures of volumes based on pre-metric units. This paper discusses the cooking measures and compares their features with those of the ancient Roman measures of capacity.

  6. Integers annual volume 2013

    CERN Document Server

    Landman, Bruce

    2014-01-01

    ""Integers"" is a refereed online journal devoted to research in the area of combinatorial number theory. It publishes original research articles in combinatorics and number theory. This work presents all papers of the 2013 volume in book form.

  7. Free volume under shear

    Science.gov (United States)

    Maiti, Moumita; Vinutha, H. A.; Sastry, Srikanth; Heussinger, Claus

    2015-10-01

    Using an athermal quasistatic simulation protocol, we study the distribution of free volumes in sheared hard-particle packings close to, but below, the random-close packing threshold. We show that under shear, and independent of volume fraction, the free volumes develop features similar to close-packed systems — particles self-organize in a manner as to mimick the isotropically jammed state. We compare athermally sheared packings with thermalized packings and show that thermalization leads to an erasure of these structural features. The temporal evolution in particular the opening-up and the closing of free-volume patches is associated with the single-particle dynamics, showing a crossover from ballistic to diffusive behavior.

  8. Generalized Partial Volume

    DEFF Research Database (Denmark)

    Darkner, Sune; Sporring, Jon

    2011-01-01

    Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV). Their theoret......Mutual Information (MI) and normalized mutual information (NMI) are popular choices as similarity measure for multimodal image registration. Presently, one of two approaches is often used for estimating these measures: The Parzen Window (PW) and the Generalized Partial Volume (GPV...

  9. Volume anomaly in ferrimagnetism

    OpenAIRE

    Pascard, H.; Globus, A.

    1981-01-01

    The volume anomaly ΔV/V due to the magnetic energy corresponding to the exchange interactions is experimentally determined for YIG. The experimental values (from 77 K to Tc) agree with the values deduced from the theoretical expression based on the Néel's theories of volume anomaly and of ferrimagnetism. These results are compared with those obtained by other authors on ferromagnetic and antiferromagnetic materials with localized magnetic moments : a reduced curve is obtained.

  10. New volume and inverse volume operators for loop quantum gravity

    OpenAIRE

    Yang, Jinsong; Ma, Yongge

    2016-01-01

    A new alternative volume operator is constructed for loop quantum gravity by using the so-called co-triad operators as building blocks. It is shown that the new volume operator shares the same qualitative properties with the standard volume operator. Moreover, a new alternative inverse volume operator is also constructed in the light of the construction of the alternative volume operator, which is possessed of the same qualitative properties as those of the alternative volume operator. The ne...

  11. Reachable volume RRT

    KAUST Repository

    McMahon, Troy

    2015-05-01

    © 2015 IEEE. Reachable volumes are a new technique that allows one to efficiently restrict sampling to feasible/reachable regions of the planning space even for high degree of freedom and highly constrained problems. However, they have so far only been applied to graph-based sampling-based planners. In this paper we develop the methodology to apply reachable volumes to tree-based planners such as Rapidly-Exploring Random Trees (RRTs). In particular, we propose a reachable volume RRT called RVRRT that can solve high degree of freedom problems and problems with constraints. To do so, we develop a reachable volume stepping function, a reachable volume expand function, and a distance metric based on these operations. We also present a reachable volume local planner to ensure that local paths satisfy constraints for methods such as PRMs. We show experimentally that RVRRTs can solve constrained problems with as many as 64 degrees of freedom and unconstrained problems with as many as 134 degrees of freedom. RVRRTs can solve problems more efficiently than existing methods, requiring fewer nodes and collision detection calls. We also show that it is capable of solving difficult problems that existing methods cannot.

  12. Volume rendering: application in static field conformal radiosurgery

    Science.gov (United States)

    Bourland, J. Daniel; Camp, Jon J.; Robb, Richard A.

    1992-09-01

    Lesions in the head which are large or irregularly shaped present challenges for radiosurgical treatment by linear accelerator or other radiosurgery modalities. To treat these lesions we are developing static field, conformal stereotactic radiosurgery. In this procedure seven to eleven megavoltage x-ray beams are aimed at the target volume. Each beam is designed from the beam's-eye view, and has its own unique geometry: gantry angle, table angle, and shape which conforms to the projected cross-section of the target. A difficulty with this and other 3- D treatment plans is the visualization of the treatment geometry and proposed treatment plan. Is the target volume geometrically covered by the arrangement of beams, and is the dose distribution adequate? To answer these questions we have been investigating the use of ANALYZETM volume rendering to display the target anatomy and the resultant dose distribution.

  13. Retrospective clinical study of simultaneous reduced dose in clinical target volume of radical intensity-modulated radiotherapy for treatment of stage Ⅲ non-small-cell lung cancer%CTV同步减量根治性IMRT对Ⅲ期NSCLC回顾观察

    Institute of Scientific and Technical Information of China (English)

    陈秀丽; 刘宁波; 赵路军; 姬凯; 石翔宇; 王大权; 陈曦; 王平

    2016-01-01

    Objective To evaluate the efficacy and adverse effects of radical intensity-modulated radiotherapy (IMRT) with simultaneous reduced dose in clinical target volume (CTV) for inoperable stage Ⅲ non-small cell lung cancer (NSCLC).Methods A retrospective analysis was performed on a total of 70 patients with stage Ⅲ NSCLC who were admitted to our hospital from 2010 to 2014.All patients received simultaneous reduced-dose IMRT with a prescribed dose of 60 Gy in 30 fractions or 60.2 Gy in 28 fractions for primary gross tumor volume (PGTV,expansion of gross tumor volume by 0.5 cm) and a prescribed dose of 54 Gy in 30 fractions or 50.4 Gy in 28 fractions for planning target volume (PTV).In the 70 patients,40 received neoadjuvant chemotherapy prior to radiotherapy,50 concurrent chemoradiotherapy,and 25 adjuvant chemotherapy after radiotherapy.Short-term treatment outcomes and adverse reactions were evaluated.The Kaplan-Meier method was used for survival analysis.Results The median follow-up time was 42.8 months (16.9-68.3 months).The short-term response rate (complete response (CR) plus partial response (PR))was 81.4%.The CR,PR,stable disease,and progressive disease rates were 7%(5/70),74% (52/70),13%(9/70),and 6%(4/70),respectively.In all patients,the median survival time was 26.6 months (5.2-68.3 months).The 2-year overall survival,local recurrence-free survival,and progression-free survival rates were 55%,68%,and 45%,respectively.In all patients,9%(6/70) had grade ≥3 radiation pneumonitis,4% (3/70) grade ≥ 3 oesophagitis,and 7% (5/70) grade ≥ 3 myelosuppression.Conclusions IMRT with simultaneous reduced dose in CTV is effective for stage Ⅲ NSCLC.It deserves further prospective studies with large sample sizes.%目的 观察CTV同步减量根治性IMRT对不能手术的Ⅲ期NSCLC患者的疗效及不良反应.方法 回顾分析2010-2014年本院收治的Ⅲ期NSCLC患者共70例,均为IMRT同步减量照射,PGTV(GTV外放0.5cm)剂量为60

  14. Google attention and target price run ups

    OpenAIRE

    Siganos, A.

    2013-01-01

    We explore the increase in the share prices of target firms before their merger announcements. We use a novelty Google search volume to proxy the market expectation hypothesis according to which firms with an abnormal upward change in Google searches are identified as firms with potential merger activity. We find that Google indicators can explain a larger percentage of the price increase in target firms before their mergers than the Financial Times. However even the Google proxy of the marke...

  15. The planning target volume margins detected by cone-beam CT in head and neck cancer patients treated by image-guided intensity modulated radiotherapy%图像引导调强放疗头颈部肿瘤摆位误差对靶区外扩边界大小的影响

    Institute of Scientific and Technical Information of China (English)

    刘均; 陈宏; 张国桥; 陈飞; 张利

    2011-01-01

    Objective To determine the planning target volume margins of head and neck cancers treated by image guided radiotherapy (IGRT).Methods 464 sets cone beam computed tomography (CBCT) images before setup correction and 126 sets CBCT images after correction were obtained from 51 head and neck cancer patients treated by IGRT in our department.The systematic and random errors were evaluated by either online or offline correction through registering the CBCT images to the planning CT.The data was divided into 3 groups according to the online correction times.Results The isocenter shift were 0.37 mm±2.37 mm, -0.43 mm±2.30 mm and 0.47 mm±2.65 mm in right-left (RL), anterior-posterior (AP) and superior-inferior (SI) directions respectively before correction, and it reduced to 0.08 mm±0.68 mm, -0.03 mm±0.74 mm and 0.03 mm±0.80 mm when evaluated by 126 sets corrected CBCT images.The planning target volume (PTV) margin from clinical target volume (CTV) before correction were:6.41 mm,6.15 mm and 7.10 mm based on two parameter model, and it reduced to 1.78 mm,1.80 mm and 1.97 mm after correction.The PTV margins were 3.8 mm,3.8 mm,4.0 mm;4.0 mm,4.0 mm,5.0 mm and 5.4 mm,5.2 mm,6.1 mm in RL, AP and SI respectively when online-correction times were more than 15 times, 11-15 times,5-10 times.Conclusions CBCT-based on online correction reduce the PTV margin for head and neck cancers treated by IGRT and ensure more precise dose delivery and less normal tissue complications.%目的 利用锥形束CT (CBCT)图像分析跟踪头颈部恶性肿瘤调强放疗分次治疗间和分次治疗内肿瘤中心误差情况,并以此误差探讨临床靶体积(CTV)外放边界大小.方法 51例头颈部肿瘤经图像引导调强放疗,其中治疗前CBCT引导464次,治疗后CBCT 126次.根据CBCT图像与计划CT图像匹配实现在线和离线分析得到位移偏差.按不同在线校正次数(15次、11~15次、5~10次)和3个方向偏差依照双模型参数

  16. Image registration and target volume margins in cone-beam computed tomography-guided intensity-modulated radiotherapy for prostate cancer%CBCT 引导前列腺癌 IMRT 图像配准及靶区外放边界分析

    Institute of Scientific and Technical Information of China (English)

    李明; 高鸿; 修霞; 侯秀玉; 徐勇刚; 钟秋子; 赵婷; 林海磊; 李高峰

    2016-01-01

    Objective To analyze the data from intensity-modulated radiotherapy ( IMRT) for prostate cancer guided by kilovoltage cone-beam computed tomography (CBCT), and to provide a clinical basis for selecting the optimal image registration method and reasonable target volume margins.Methods A total of 16 patients with prostate cancer who received radical IMRT were enrolled, and CBCT for online position verification was performed 214 times.The images were obtained after conventional skin marking and laser alignment, and automatic registration, bone registration, soft tissue registration, and manual registration were performed for CBCT images and planned CT images.The differences between these four registration methods were evaluated, and the margins for extending clinical target volume into planning target volume (PTV) were calculated.Results The setup errors in left-right, anterior-posterior, and cranial-caudal directions for automatic registration, bone registration, soft tissue registration, and manual registration were-0.6±2.8 mm/-0.6±4.5 mm/-0.6±3.8 mm,-0.7±2.7 mm/-0.9±4.5 mm/-0.8±4.1 mm,-0.8± 2.6 mm/-0.3±4.4 mm/-1.1±4.0 mm, and-0.6±2.9 mm/-0.7±5.1 mm/-0.9±3.9 mm, respectively. There were no significant differences between the four registration methods.The margins for extension in the left-right, anterior-posterior, and cranial-caudal directions were calculated as 4.7 mm, 5.2 mm, and 6.5 mm, respectively.Conclusions With a comprehensive consideration of various factors, a default setting of automatic registration and manual fine adjustment is appropriate for CBCT-guided radiotherapy for prostate cancer.The margins for extension in the left-right, anterior-posterior, and cranial-caudal directions are 4.7 mm, 5.2 mm, and 6.5 mm, respectively.%目的:通过分析千伏级 CBCT 引导前列腺癌 IMRT 的数据,为选择合理的图像配准方法和适宜的外放边界提供临床依据。方法针对16例接受根治性 IMRT 的

  17. Factors influencing the difference between forecasted and actual drug sales volumes under the price-volume agreement in South Korea.

    Science.gov (United States)

    Park, Sun-Young; Han, Euna; Kim, Jini; Lee, Eui-Kyung

    2016-08-01

    This study analyzed factors contributing to increases in the actual sales volumes relative to forecasted volumes of drugs under price-volume agreement (PVA) policy in South Korea. Sales volumes of newly listed drugs on the national formulary are monitored under PVA policy. When actual sales volume exceeds the pre-agreed forecasted volume by 30% or more, the drug is subject to price-reduction. Logistic regression assessed the factors related to whether drugs were the PVA price-reduction drugs. A generalized linear model with gamma distribution and log-link assessed the factors influencing the increase in actual volumes compared to forecasted volume in the PVA price-reduction drugs. Of 186 PVA monitored drugs, 34.9% were price-reduction drugs. Drugs marketed by pharmaceutical companies with previous-occupation in the therapeutic markets were more likely to be PVA price-reduction drugs than drugs marketed by firms with no previous-occupation. Drugs of multinational pharmaceutical companies were more likely to be PVA price-reduction drugs than those of domestic companies. Having more alternative existing drugs was significantly associated with higher odds of being PVA price-reduction drugs. Among the PVA price-reduction drugs, the increasing rate of actual volume compared to forecasted volume was significantly higher in drugs with clinical usefulness. By focusing the negotiation efforts on those target drugs, PVA policy can be administered more efficiently with the improved predictability of the drug sales volumes.

  18. Nuclear maintenance work volume model

    International Nuclear Information System (INIS)

    This presentation will cover a work volume model, detailing what contributes to a maintenance backlog and demonstrate the impact of these contributing factors on it's reduction. In our quest to achieve sustainable nuclear excellence, we have engaged in many debates over our degree of success in reducing the maintenance backlog at Ontario Power Generation plants. The backlog is a volume of work and a simplified analogy would be to consider it as the water level in a tank. The inflow would be the new work requests/minor work orders not completed by the Fix It Now Team, and the outflow would be the completed work orders. The equilibrium in the tank would be the result of the incoming rate of new work versus the rate of outgoing completed work. We can accommodate increasing levels for short durations, but our success depends on our ability to manage the process and achieving timely long term reduction in backlog. Although everyone seemed to have an understanding for the type of change required, it was difficult to quantify the optimum combination. Increasing the work force always seems to be an obvious choice, along with productivity improvements but there must be careful consideration given to the preventative maintenance program and resource allocation such as Support Staff, Fix It Now Team, Outages, Projects, etc. Various other factors impacting on our work rates would include training loads, sick leave and overtime. A need was identified for some analytical tool that would illustrate if our goals were attainable with our present course of action, and demonstrate what changes needed to be implemented in order to be successful. We developed a model consisting of an Excel spreadsheet that trends the backlog for each maintenance workgroup. The user populates the model with specific historical data for plant resource profiles and work execution. The program generates two sets of charts for each maintenance groups, one for actual data and another for target data. The

  19. WYSIWYG (What You See is What You Get) volume visualization.

    Science.gov (United States)

    Guo, Hanqi; Mao, Ningyu; Yuan, Xiaoru

    2011-12-01

    In this paper, we propose a volume visualization system that accepts direct manipulation through a sketch-based What You See Is What You Get (WYSIWYG) approach. Similar to the operations in painting applications for 2D images, in our system, a full set of tools have been developed to enable direct volume rendering manipulation of color, transparency, contrast, brightness, and other optical properties by brushing a few strokes on top of the rendered volume image. To be able to smartly identify the targeted features of the volume, our system matches the sparse sketching input with the clustered features both in image space and volume space. To achieve interactivity, both special algorithms to accelerate the input identification and feature matching have been developed and implemented in our system. Without resorting to tuning transfer function parameters, our proposed system accepts sparse stroke inputs and provides users with intuitive, flexible and effective interaction during volume data exploration and visualization. PMID:22034329

  20. Volumes of chain links

    CERN Document Server

    Kaiser, James; Rollins, Clint

    2011-01-01

    Agol has conjectured that minimally twisted n-chain links are the smallest volume hyperbolic manifolds with n cusps, for n at most 10. In his thesis, Venzke mentions that these cannot be smallest volume for n at least 11, but does not provide a proof. In this paper, we give a proof of Venzke's statement. The proof for n at least 60 is completely rigorous. The proof for n between 11 and 59 uses a computer calculation, and can be made rigorous for manifolds of small enough complexity, using methods of Moser and Milley. Finally, we prove that the n-chain link with 2m or 2m+1 half-twists cannot be the minimal volume hyperbolic manifold with n cusps, provided n is at least 60 or |m| is at least 8, and we give computational data indicating this remains true for smaller n and |m|.

  1. HARNESSING BIG DATA VOLUMES

    Directory of Open Access Journals (Sweden)

    Bogdan DINU

    2014-04-01

    Full Text Available Big Data can revolutionize humanity. Hidden within the huge amounts and variety of the data we are creating we may find information, facts, social insights and benchmarks that were once virtually impossible to find or were simply inexistent. Large volumes of data allow organizations to tap in real time the full potential of all the internal or external information they possess. Big data calls for quick decisions and innovative ways to assist customers and the society as a whole. Big data platforms and product portfolio will help customers harness to the full the value of big data volumes. This paper deals with technical and technological issues related to handling big data volumes in the Big Data environment.

  2. Aperiodic Volume Optics

    Science.gov (United States)

    Gerke, Tim D.

    Presented in this thesis is an investigation into aperiodic volume optical devices. The three main topics of research and discussion are the aperiodic volume optical devices that we call computer-generated volume holograms (CGVH), defects within periodic 3D photonic crystals, and non-periodic, but ordered 3D quasicrystals. The first of these devices, CGVHs, are designed and investigated numerically and experimentally. We study the performance of multi-layered amplitude computer-generated volume holograms in terms of efficiency and angular/frequency selectivity. Simulation results show that such aperiodic devices can increase diffraction efficiency relative to periodic amplitude volume holograms while maintaining angular and wavelength selectivity. CGVHs are also designed as voxelated volumes using a new projection optimization algorithm. They are investigated using a volumetric diffraction simulation and a standard 3D beam propagation technique as well as experimentally. Both simulation and experiment verify that the structures function according to their design. These represent the first diffractive structures that have the capacity for generating arbitrary transmission and reflection wave fronts and that provide the ability for multiplexing arbitrary functionality given different illumination conditions. Also investigated and discussed in this thesis are 3D photonic crystals and quasicrystals. We demonstrate that these devices can be fabricated using a femtosecond laser direct writing system that is particularly appropriate for fabrication of such arbitrary 3D structures. We also show that these devices can provide 3D partial bandgaps which could become complete bandgaps if fabricated using high index materials or by coating lower index materials with high index metals. Our fabrication method is particularly suited to the fabrication of engineered defects within the periodic or quasi-periodic systems. We demonstrate the potential for fabricating defects within

  3. Volume holographic memory

    Directory of Open Access Journals (Sweden)

    Cornelia Denz

    2000-05-01

    Full Text Available Volume holography represents a promising alternative to existing storage technologies. Its parallel data storage leads to high capacities combined with short access times and high transfer rates. The design and realization of a compact volume holographic storage demonstrator is presented. The technique of phase-coded multiplexing implemented to superimpose many data pages in a single location enables to store up to 480 holograms per storage location without any moving parts. Results of analog and digital data storage are shown and real time optical image processing is demonstrated.

  4. Design for volume reduction

    NARCIS (Netherlands)

    Wever, R.; Boks, C.; Stevels, A.

    2007-01-01

    Traditionally packaging design-for-sustainability (DfS) strongly focuses on resource conservation and material recycling. The type and amount of materials used has been the driver in design. For consumer electronics (CE) products this weight-based approach is too limited; a volume-based approach is

  5. Introduction to the Volume.

    Science.gov (United States)

    Emihovich, Catherine; Schroder, Barbara; Panofsky, Carolyn P.

    1999-01-01

    Introduces a volume that examines the issue of critical thinking and whether or not it is culturally specific, discussing recent research on the subject. The papers focus on critical thinking and culture, historical consciousness and critical thinking, critical thinking as cultural-historical practice, culture and the development of critical…

  6. Postoperative volume balance

    DEFF Research Database (Denmark)

    Frost, H; Mortensen, C.R.; Secher, N H;

    2016-01-01

    In healthy humans, stroke volume (SV) and cardiac output (CO) do not increase with expansion of the central blood volume by head-down tilt or administration of fluid. Here, we exposed 85 patients to Trendelenburg's position about one hour after surgery while cardiovascular variables were determined...... non-invasively by Modelflow. In Trendelenburg's position, SV (83 ± 19 versus 89 ± 20 ml) and CO (6·2 ± 1·8 versus 6·8 ± 1·8 l/min; both P... (39%) with a > 10% increase in SV (from 78 ± 16 to 90 ± 17 ml) corresponding to an increase in CO from 5·9 ± 1·5 to 6·9 ± 1·6 l min(-1) (Phead-down, administration of 250 ml Ringer's lactate solution increased SV (to 88 ± 18 ml) and CO (to 6·8 ± 1·7 l min(-1) ). In conclusion...

  7. Mean nuclear volume

    DEFF Research Database (Denmark)

    Mogensen, O.; Sørensen, Flemming Brandt; Bichel, P.;

    1999-01-01

    We evaluated the following nine parameters with respect to their prognostic value in females with endometrial cancer: four stereologic parameters [mean nuclear volume (MNV), nuclear volume fraction, nuclear index and mitotic index], the immunohistochemical expression of cancer antigen (CA125...... included total abdominal hysterectomy and bilateral salpingo-oophorectomy. All patients underwent radical operations. The tumors were classified postsurgically as P-stage I-III. All patients received the same postoperative radiation therapy. The surviving patients were observed for a median of 6.4 years...... (range 5.0-8.4 years). Cox regression analysis (automatic forward selection) showed the MNV to be the most significant prognostic parameter followed by the P-stage. Patients who had localized tumors or tumors with small nuclei had a better probability of surviving than did women with advanced tumors...

  8. Mixed volumes of hypersimplices

    OpenAIRE

    Liu, Gaku

    2014-01-01

    In this paper we consider mixed volumes of combinations of hypersimplices. These numbers, called "mixed Eulerian numbers", were first considered by A. Postnikov and were shown to satisfy many properties related to Eulerian numbers, Catalan numbers, binomial coefficients, etc. We give a general combinatorial interpretation for mixed Eulerian numbers and prove the above properties combinatorially. In particular, we show that each mixed Eulerian number enumerates a certain set of permutations in...

  9. Prostate cancer: Doses and volumes of radiotherapy; Cancer de prostate: doses et volumes cibles

    Energy Technology Data Exchange (ETDEWEB)

    Hennequin, C.; Rivera, S.; Quero, L. [Service de cancerologie-radiotherapie, hopital Saint-Louis, AP-HP, 75 - Paris (France); Latorzeff, I. [Service de radiotherapie, groupe Oncorad-Garonne, clinique Pasteur, -l' Atrium-, 31 - Toulouse (France)

    2010-10-15

    Radiotherapy is nowadays a major therapeutic option in prostate cancer. Technological improvements allowed dose escalation without increasing late toxicity. Some randomized trials have shown that dose escalation decreases the biochemical failure rate, without any benefit in survival with the present follow-up. However, some studies indicate that the distant metastases rate is also decreased. Most of these studies have been done without hormonal treatment, and the role of dose escalation in case of long-term androgen deprivation is unknown. The target volume encompassed the whole gland: however, complete or partial focal treatment of the prostate can be done with sophisticated IMRT technique and must be evaluated. Proximal part of the seminal vesicles must be included in the target volumes. The role of nodal irradiation is another debate, but it could be logically proposed for the unfavourable group. (authors)

  10. 4D-CT-based plan target volume (PTV)definition compared with conventional PTV definition using general margin in radiotherapy for lung cancer%肺癌放疗中四维CT技术与传统方法勾画靶区计划比较

    Institute of Scientific and Technical Information of China (English)

    鞠潇; 李明辉; 周宗玫; 张可; 韩伟; 符贵山; 曹莹; 王绿化

    2014-01-01

    目的 比较肺癌放疗中四维CT(4D-CT)技术与传统方法勾画计划靶区体积(PTV)的治疗计划差异.方法 选择10例肺癌患者,均行4D-CT及普通螺旋CT定位扫描,分别采用4D-CT和常规经验外扩PTV方法确定计划靶区(PTV4D和PTWconv)和制定治疗计划(Plan4D和Planconv),测量大体肿瘤体积(GTV)质心在三维方向上随呼吸运动的位移,计算三维空间位移向量| (v)|.比较4D-CT技术与传统方法所得PTV、双肺平均受量(MLD)、双肺V5(Vx表示接受xGy照射的百分体积)、双肺V1o、双肺V15、双肺V20、心脏平均受量(MHD)、心脏V30、心脏V40、99%靶体积受照剂量(D99)和95%靶体积受照剂量(D95)的变化,并分析其与三维空间位移向量|(v)|的关系.结果 10例患者中,8例患者PTV4D< PTVconv,减少(13.0±8.0)%(P=0.018),2例患者PTV4D> PTVconv.GTV质心三维空间位移向量|(v)|为(0.78±0.72)cm.MLD4D较MLDconv减少(8.6±9.9)%(P=0.037).Plan4D的双肺V5、V10、V15、V20分别较Planconv减少(7.2±10.5)%、(5.5±8.9)%、(6.5±8.4)%和(5.7±7.4)%(均P<0.05).10例患者Plan4D和Planconv的D99分别为(56.68±1.82) Gy和(56.12±2.23) Gy(P=0.092),Plan4D和Planconv的D95分别为(60.04±0.46) Gy和(59.86±0.51) Gy (P =0.026).PTV4D/PTVconv与三维空间位移向量| (v) |呈正相关关系(P =0.008),D994D/D99conv与| (v) |呈负相关关系(P=0.002),D994D/D99conv、(MLDconv-MLD4D)/MLDconv、双肺(V5conv-V54D)/V5conv、双肺(V10conv-V104D)/V10conv、(MHDconv-MHD4D)/MHDconv、心脏(V30conv-V304D)/V30convv与PTV4D/PTVconv呈负相关关系(均P<0.05).结论 4D-CT可准确评价肺部肿瘤随呼吸运动的位移,应用4D-CT数据定义靶区及制定计划,可缩小肿瘤动度小的PTV,提高靶区内剂量,减少正常组织受量,对于肿瘤动度大的患者,可在不明显增加正常组织受量的前提下,避免靶区遗漏.%Objective To investigate the dosimetric benefit of 4D-CT in the planning target volume (PTV) definition

  11. Information architecture. Volume 4: Vision

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The Vision document marks the transition from definition to implementation of the Department of Energy (DOE) Information Architecture Program. A description of the possibilities for the future, supported by actual experience with a process model and tool set, points toward implementation options. The directions for future information technology investments are discussed. Practical examples of how technology answers the business and information needs of the organization through coordinated and meshed data, applications, and technology architectures are related. This document is the fourth and final volume in the planned series for defining and exhibiting the DOE information architecture. The targeted scope of this document includes DOE Program Offices, field sites, contractor-operated facilities, and laboratories. This document paints a picture of how, over the next 7 years, technology may be implemented, dramatically improving the ways business is conducted at DOE. While technology is mentioned throughout this document, the vision is not about technology. The vision concerns the transition afforded by technology and the process steps to be completed to ensure alignment with business needs. This goal can be met if those directing the changing business and mission-support processes understand the capabilities afforded by architectural processes.

  12. Electrically charged targets

    Science.gov (United States)

    Goodman, Ronald K.; Hunt, Angus L.

    1984-01-01

    Electrically chargeable laser targets and method for forming such charged targets in order to improve their guidance along a predetermined desired trajectory. This is accomplished by the incorporation of a small amount of an additive to the target material which will increase the electrical conductivity thereof, and thereby enhance the charge placed upon the target material for guidance thereof by electrostatic or magnetic steering mechanisms, without adversely affecting the target when illuminated by laser energy.

  13. Environmental Report 1996, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Harrach, R.J.

    1996-01-01

    This is Volume 2 of the Lawrence Livermore National Laboratory`s (LLNL`s) annual Environmental Report 1996, prepared for the US Department of Energy. Volume 2 supports Volume 1 summary data and is essentially a detailed data report that provides individual data points, where applicable. Volume 2 includes information on monitoring of air, air effluents, sewerable water, surface water, ground water, soil and sediment, vegetation and foodstuff, environmental radiation, and quality assurance.

  14. Calculus Students' Understanding of Volume

    Science.gov (United States)

    Dorko, Allison; Speer, Natasha M.

    2013-01-01

    Researchers have documented difficulties that elementary school students have in understanding volume. Despite its importance in higher mathematics, we know little about college students' understanding of volume. This study investigated calculus students' understanding of volume. Clinical interview transcripts and written responses to volume…

  15. New volume and inverse volume operators for loop quantum gravity

    CERN Document Server

    Yang, Jinsong

    2016-01-01

    A new alternative volume operator is constructed for loop quantum gravity by using the so-called co-triad operators as building blocks. It is shown that the new volume operator shares the same qualitative properties with the standard volume operator. Moreover, a new alternative inverse volume operator is also constructed in the light of the construction of the alternative volume operator, which is possessed of the same qualitative properties as those of the alternative volume operator. The new inverse volume operator can be employed to construct the Hamiltonian operator of matter fields, which may lead to an anomaly-free on shell quantum constraint algebra without any special restriction on the regularization procedure for gravity coupled to matter fields.

  16. New volume and inverse volume operators for loop quantum gravity

    Science.gov (United States)

    Yang, Jinsong; Ma, Yongge

    2016-08-01

    A new alternative volume operator is constructed for loop quantum gravity by using the so-called cotriad operators as building blocks. It is shown that the new volume operator shares the same qualitative properties with the standard volume operator. Moreover, a new alternative inverse volume operator is also constructed in the light of the construction of the alternative volume operator, which is possessed of the same qualitative properties as those of the alternative volume operator. The new inverse volume operator can be employed to construct the Hamiltonian operator of matter fields, which may lead to an anomaly-free on-shell quantum constraint algebra without any special restriction on the regularization procedure for gravity coupled to matter fields.

  17. Radwaste '86: proceedings volume

    International Nuclear Information System (INIS)

    The volume contains all the papers presented at the above Conference, which was held in Cape Town, South Africa from 7 to 12 September 1986. A total of 55 contributions cover the full spectrum of the theme of the Conference, which was subdivided into four sessions. Conditioning, treatment and management of radioactive waste: 12 papers reporting on experiences in various countries, as well as specialist topics such as the extraction of radioactive contaminants from reactor pool water. Containment, safe handling and long-term integrity of ILLW packages: 2 papers dealing with cask design. Transport and storage of radwaste and spent fuel: 7 papers ranging from broad overviews to specific operations in different parts of the world. Radioactive waste disposal and environmental impact: 32 papers covering topics from site selection, design and operation, to modelling and monitoring studies. South Africa's Vaalputs radioactive waste disposal facility is comprehensively described. The volume is a useful reference for anyone interested in the disposal of radioactive waste, especially in arid environments, as well as its treatment and management prior to disposal, and will appeal to a wide range of disciplines including engineers, geologists, geophysicists, life scientists and environmentalists. Of particular interest would be the intensive studies undertaken in South Africa prior to the establishment of a radioactive waste repository in that country

  18. Target Visualization at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Daniel Abraham [Univ. of California, Davis, CA (United States)

    2011-01-01

    As the National Ignition Facility continues its campaign to achieve ignition, new methods and tools will be required to measure the quality of the targets used to achieve this goal. Techniques have been developed to measure target surface features using a phase-shifting diffraction interferometer and Leica Microsystems confocal microscope. Using these techniques we are able to produce a detailed view of the shell surface, which in turn allows us to refine target manufacturing and cleaning processes. However, the volume of data produced limits the methods by which this data can be effectively viewed by a user. This paper introduces an image-based visualization system for data exploration of target shells at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. It aims to combine multiple image sets into a single visualization to provide a method of navigating the data in ways that are not possible with existing tools.

  19. Volume of an Industrial Autoclave

    Directory of Open Access Journals (Sweden)

    Nicholas Madaffari

    2010-01-01

    Full Text Available We were able to determine the volume of an industrial autoclave sterilization tank using a technique learned in calculus. By measuring the dimensions of the tank and roughly estimating the equation of curvature at the ends of the tank, we were able to revolve half of the end of the tank around the x axis to get its fluid volume. Adding the two volumes of the ends and the volume of the cylindrical portion on the tank yielded the total volume.

  20. TARGET COSTING FUNCTIONS

    OpenAIRE

    Dimi OFILEANU

    2015-01-01

    This article aims to highlight the concept of Target Costing. Based on the characteristics of Target Costing, identified in specialized literature, the article presents its main advantages and disadvantages. Also, a comparison is being made between Target Cost and Traditional Cost (in its traditional form, the cost represents an independent variable on the basis of which the sell price is established; and in the Target Cost form the cost represents a dependent variable which is determined on ...

  1. Multilayer polymer microspot targets

    International Nuclear Information System (INIS)

    Last year the authors reported on the development of a seeded microspot x-ray diagnostic target. This target consisted of a 300-μm-diam, 2-μm-thick disk of silicon or sulfur-seeded hydrocarbon polymer nested tightly in a hole in a 2-μm-thick film of pure hydrocarbon polymer. This year they extended our work on the microspot target, fully encapsulating the microspot in what they call the multilayer polymer microspot target

  2. The Targeting of Advertising

    OpenAIRE

    Ganesh Iyer; David Soberman; J. Miguel Villas-Boas

    2005-01-01

    An important question that firms face in advertising is developing effective media strategy. Major improvements in the quality of consumer information and the growth of targeted media vehicles allow firms to precisely target advertising to consumer segments within a market. This paper examines advertising strategy when competing firms can target advertising to different groups of consumers within a market. With targeted advertising, we find that firms advertise more to consumers who have a st...

  3. Target Price Accuracy

    OpenAIRE

    Alexander G. Kerl

    2011-01-01

    This study analyzes the accuracy of forecasted target prices within analysts’ reports. We compute a measure for target price forecast accuracy that evaluates the ability of analysts to exactly forecast the ex-ante (unknown) 12-month stock price. Furthermore, we determine factors that explain this accuracy. Target price accuracy is negatively related to analyst-specific optimism and stock-specific risk (measured by volatility and price-to-book ratio). However, target price accuracy is positive...

  4. An actionable climate target

    Science.gov (United States)

    Geden, Oliver

    2016-05-01

    The Paris Agreement introduced three mitigation targets. In the future, the main focus should not be on temperature targets such as 2 or 1.5 °C, but on the target with the greatest potential to effectively guide policy: net zero emissions.

  5. High Power Cryogenic Targets

    Energy Technology Data Exchange (ETDEWEB)

    Gregory Smith

    2011-08-01

    The development of high power cryogenic targets for use in parity violating electron scattering has been a crucial ingredient in the success of those experiments. As we chase the precision frontier, the demands and requirements for these targets have grown accordingly. We discuss the state of the art, and describe recent developments and strategies in the design of the next generation of these targets.

  6. COMPASS polarized target for Drell-Yan

    CERN Document Server

    Pešek, M

    2014-01-01

    In the COMPASS Drell–Yan experiment the pion beam with momen tum of 190 GeV/ c and in- tensity up to 10 8 pions/s will interact with transversely polarized proton t arget producing muon pair via Drell–Yan process. The solid-state NH 3 will be polarized by dynamic nuclear polar- ization. Maximum polarization reached during data taking i s expected to be up to 90%. The non-interacting beam and other particles produced inside t he target will be stopped in the hadron absorber after the target. Two target cells, sepparated by a 20 cm gap in between, each 55 cm long and 4 cm in diameter give the target material volume about 691 cm 3 . The target platform needs to be moved by 2.3 m in upstream dire ction from the position used in previous experiments in order to accomodate the absorber. D uring the beam time higher radiation is expected in the area of the control room. Thus a new target r emote control system is needed. The target magnet is undergoing a substantial upgrade. Drell–Yan data taking is expected t...

  7. Targeted cancer therapies

    Institute of Scientific and Technical Information of China (English)

    Li Yan; Neal Rosen; Carlos Arteaga

    2011-01-01

    With unprecedented understanding of molecular events underlying human cancer in this genomic era, a large number of drugs specifically targeting hypothesized oncogenic drivers to which tumors are potentially addicted to have been developed and continue to be developed. These targeted cancer therapies are being actively tested in clinical trials with mixed successes. This editorial provides an overview on successful targeted cancer drugs on the market and those drugs that are in late clinical development stages. Importantly, the article lays out main challenges in developing molecular targeted therapies and potential path forward to overcome these challenges, as well as opportunities for China in this new era of targeted agents. The editorial serves as an introduction to the Targeted Cancer Therapies serias that will review in depth of major pathways and drugs targeting these pathways to be published in the coming issues of the Chinese Journal of Cancer.

  8. Polarized targets and beams

    International Nuclear Information System (INIS)

    First the experimental situation of the single-pion photoproduction and the photodisintegration of the deuteron is briefly discussed. Then a description of the Bonn polarization facilities is given. The point of main effort is put on the polarized target which plays a vital role in the program. A facility for photon induced double polarization experiments at ELSA will be presented in section 4. Properties of a tensor polarized deuteron target are discussed in section 5. The development in the field of polarized targets, especially on new target materials, enables a new generation of polarized target experiments with (polarized) electrons. Some comments on the use of a polarized target in combination with electron beams will be discussed in section 6. Electron deuteron scattering from a tensor polarized deuteron target is considered and compared with other experimental possibilities. (orig./HSI)

  9. SHADOW MAPPING OR SHADOW VOLUME?

    Directory of Open Access Journals (Sweden)

    Hoshang Kolivand

    2011-01-01

    Full Text Available In this paper two techniques of shadow generation are described. Volume shadow is geometric base but shadow mapping is image base. Silhouette detection is a most expensive step to create volume shadow. Two algorithms to recognize silhouette are introduced. Stencil buffer and Z- buffer are two other tools for creating shadow by volume shadow technique. Both algorithms are implemented in virtual environment with moveable light source. Triangular method and the Visible-non visible method are introduced. The recent traditional silhouette detection and implementation techniques used in volume shadow algorithm are improved. With introduce flowchart of both algorithms, the last volume shadow algorithm using stencil buffer is rewritten. A very simple algorithm to create volume shadow is proposed. The last shadow mapping algorithm is rewritten. These techniques are poised to bring realism into commercial games. It may be use in virtual reality applications.

  10. Heliophysics 3 Volume Set

    Science.gov (United States)

    Schrijver, Carolus J.; Siscoe, George L.

    2010-11-01

    Volume 1: Preface; 1. Prologue Carolus J. Schrijver and George L. Siscoe; 2. Introduction to heliophysics Thomas J. Bogdan; 3. Creation and destruction of magnetic field Matthias Rempel; 4. Magnetic field topology Dana W. Longcope; 5. Magnetic reconnection Terry G. Forbes; 6. Structures of the magnetic field Mark B. Moldwin, George L. Siscoe and Carolus J. Schrijver; 7. Turbulence in space plasmas Charles W. Smith; 8. The solar atmosphere Viggo H. Hansteen; 9. Stellar winds and magnetic fields Viggo H. Hansteen; 10. Fundamentals of planetary magnetospheres Vytenis M. Vasyliūnas; 11. Solar-wind magnetosphere coupling: an MHD perspective Frank R. Toffoletto and George L. Siscoe; 12. On the ionosphere and chromosphere Tim Fuller-Rowell and Carolus J. Schrijver; 13. Comparative planetary environments Frances Bagenal; Bibliography; Index. Volume 2: Preface; 1. Perspective on heliophysics George L. Siscoe and Carolus J. Schrijver; 2. Introduction to space storms and radiation Sten Odenwald; 3. In-situ detection of energetic particles George Gloeckler; 4. Radiative signatures of energetic particles Tim Bastian; 5. Observations of solar and stellar eruptions, flares, and jets Hugh Hudson; 6. Models of coronal mass ejections and flares Terry Forbes; 7. Shocks in heliophysics Merav Opher; 8. Particle acceleration in shocks Dietmar Krauss-Varban; 9. Energetic particle transport Joe Giacalone; 10. Energy conversion in planetary magnetospheres Vytenis Vasyliūnas; 11. Energization of trapped particles Janet Green; 12. Flares, CMEs, and atmospheric responses Tim Fuller-Rowell and Stanley C. Solomon; 13. Energetic particles and manned spaceflight 358 Stephen Guetersloh and Neal Zapp; 14. Energetic particles and technology Alan Tribble; Appendix I. Authors and editors; List of illustrations; List of tables; Bibliography; Index. Volume 3: Preface; 1. Interconnectedness in heliophysics Carolus J. Schrijver and George L. Siscoe; 2. Long-term evolution of magnetic activity of Sun

  11. Flayer target acceleration and energy transfer at its collision with massive targets

    International Nuclear Information System (INIS)

    Investigations of efficiency of macroparticle acceleration and crater creation processes for the two wavelengths of the PALS (Prague Asterix Laser System) facility laser beam: λ1=1.315 μm and λ3=0.438 μm, and two types of targets made of Al: single massive target and double target consisting of a foil (thickness of 6 and 11 μm) placed before the massive target at the distance of 200-500 μm are presented. Targets were irradiated by the iodine laser beam: EL=120-240 J, the focal spot diameter of 250 μm, and the pulse duration of 0.4 ns. Velocities of the accelerated macroparticles as well as electron density distributions of plasma stream were determined by means of a 3-frame interferometry. Shape and volume of craters were obtained employing crater replica technology and microscopy measurement. Experimental results were analyzed and interpreted by means of two-dimensional theoretical and numerical simulations. Energy transfer as well as two- dimensional shock wave generation and crater formation at the collision of laser-driven macroparticle with massive target have been described. The values of laser energy absorption coefficient, ablation loading efficiency and efficiency of energy transfer at the laser-driven macroparticle impact have been obtained at the different wavelength of laser radiation by crater volume measurement data. (author)

  12. Volume and Surface-Enhanced Volume Negative Ion Sources

    CERN Document Server

    Stockli, M P

    2013-01-01

    H- volume sources and, especially, caesiated H- volume sources are important ion sources for generating high-intensity proton beams, which then in turn generate large quantities of other particles. This chapter discusses the physics and technology of the volume production and the caesium-enhanced (surface) production of H- ions. Starting with Bacal's discovery of the H- volume production, the chapter briefly recounts the development of some H- sources, which capitalized on this process to significantly increase the production of H- beams. Another significant increase was achieved in the 1990s by adding caesiated surfaces to supplement the volume-produced ions with surface-produced ions, as illustrated with other H- sources. Finally, the focus turns to some of the experience gained when such a source was successfully ramped up in H- output and in duty factor to support the generation of 1 MW proton beams for the Spallation Neutron Source.

  13. Semipermanent Volumization by an Absorbable Filler: Onlay Injection Technique to the Bone

    Directory of Open Access Journals (Sweden)

    Takanobu Mashiko, MD

    2013-04-01

    Conclusions: Semipermanent volumizing effects can be achieved by HA injection if the target area has an underlying bony floor. Periosteal stem cells may be activated by HA injection and may contribute to persistent volumizing effects. This treatment may be a much less invasive alternative to fat or bone grafting.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-22

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

  15. Influences of Motion Artifacts on Three-Dimensional Reconstruction Volume and Conformal Radiotherapy Planning

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To investigate the influences of motion artifacts on three-dimensional (3D) reconstruction volume and conformal radiotherapy planning. Methods: A phantom which can mimic the clip motion of lung tumor along the cranial-caudal direction is constructed by step motor, small ball of polyethylene and potato. Ten different scan protocols were set and CT data of the phantom were acquired by using a commercial GE LightSpeed16 CT scanner. The 3D reconstruction of the CT data was implemented by adopting volume-rendering technology of GE AdvantageSim 6.0 system. The reconstructed volumes of each target in different scan protocols were measured through 3D measuring tools. Thus, relative deviations of the reconstruction volumes between moving targets and static ones were determined. The three-dimensional conformal radiation therapy (3DCRT) plans and conformal fields were created and compared for a static/moving target with the WiMRT treatment planning system (TPS). Results:For a static target, there was no obvious difference among the 3D reconstruction volumes when the CT data were acquired with different pitches and slices. The appearance of 3D reconstruction volume and 3D conformal field of a moving target was quite different from that of static one. The maximum relative deviation is nearly 90% for a moving target scanned with different scan protocols. The relative deviations are variable among the different targets, about from -39.8% to 89.5% for a smaller target and from -18.4% to 20.5% for a larger one.Conclusion:The motion artifacts have great effects on 3D-CRT planning and reconstruction volume, which will greatly induce distorted conformal radiation fields and false DVHs for a moving target.

  16. Evaluating the agreement between tumour volumetry and the estimated volumes of tumour lesions using an algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Laubender, Ruediger P. [German Cancer Consortium (DKTK), Heidelberg (Germany); University Hospital Munich - Campus Grosshadern, Institute of Medical Informatics, Biometry, and Epidemiology (IBE), Munich (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Lynghjem, Julia; D' Anastasi, Melvin; Graser, Anno [University Hospital Munich - Campus Grosshadern, Institute for Clinical Radiology, Munich (Germany); Heinemann, Volker; Modest, Dominik P. [University Hospital Munich - Campus Grosshadern, Department of Medical Oncology, Munich (Germany); Mansmann, Ulrich R. [University Hospital Munich - Campus Grosshadern, Institute of Medical Informatics, Biometry, and Epidemiology (IBE), Munich (Germany); Sartorius, Ute; Schlichting, Michael [Merck KGaA, Darmstadt (Germany)

    2014-07-15

    To evaluate the agreement between tumour volume derived from semiautomated volumetry (SaV) and tumor volume defined by spherical volume using longest lesion diameter (LD) according to Response Evaluation Criteria In Solid Tumors (RECIST) or ellipsoid volume using LD and longest orthogonal diameter (LOD) according to World Health Organization (WHO) criteria. Twenty patients with metastatic colorectal cancer from the CIOX trial were included. A total of 151 target lesions were defined by baseline computed tomography and followed until disease progression. All assessments were performed by a single reader. A variance component model was used to compare the three volume versions. There was a significant difference between the SaV and RECIST-based tumour volumes. The same model showed no significant difference between the SaV and WHO-based volumes. Scatter plots showed that the RECIST-based volumes overestimate lesion volume. The agreement between the SaV and WHO-based relative changes in tumour volume, evaluated by intraclass correlation, showed nearly perfect agreement. Estimating the volume of metastatic lesions using both the LD and LOD (WHO) is more accurate than those based on LD only (RECIST), which overestimates lesion volume. The good agreement between the SaV and WHO-based relative changes in tumour volume enables a reasonable approximation of three-dimensional tumour burden. (orig.)

  17. Targeted tumor radiotherapy

    Directory of Open Access Journals (Sweden)

    Unak Perihan

    2002-01-01

    Full Text Available Targeted tumor radiotherapy is selectively delivery of curative doses of radiation to malignant sites. The aim of the targeted tumor radiotherapy is to use the radionuclides which have high LET particle emissions conjugated to appropriate carrier molecules. The radionuclides are selectively collected by tumor cells, depositing lethal doses to tumor cells while no admission occur to normal cells. In theory, targeted radiotherapy has several advantages over conventional radiotherapy since it allows a high radiation dose to be administered without causing normal tissue toxicity, although there are some limitations in the availability of appropriate targeting agents and in the calculations of administered doses. Therefore, for routine clinical applications more progress is still needed. In this article, the potential use of targeted tumor radiotherapy is briefly reviewed. More general aspects and considerations, such as potential radionuclides, mechanisms of tumor targeting was also outlined.

  18. Assessing the optimal liquid volume to be sprayed on isolated olive trees according to their canopy volumes.

    Science.gov (United States)

    Miranda-Fuentes, A; Llorens, J; Rodríguez-Lizana, A; Cuenca, A; Gil, E; Blanco-Roldán, G L; Gil-Ribes, J A

    2016-10-15

    The application of pesticides to traditional and intensive olive orchards in Southern Spain has led to environmental problems. More specifically, the lack of an accurate, useful criterion to regulate the spray volume in relation to canopy characteristics has led to spray drift and runoff, which are threats to local ecosystems. The aim of this study was to determine the optimal relationship between canopy volume and the spray application volume, called specific spray volume, CV, through laboratory and field trials. In the laboratory trial, 6 specific spray volumes (0.05, 0.08, 0.10, 0.12, 0.15, and 0.20Lm(-3)) were tested in a specially designed structure containing small, live olive trees in order to simulate an intensive plantation system. The model aimed to evaluate the coverage of pesticide application on water sensitive paper (WSP) collectors. In the field trial, the three laboratory specific spray volumes that gave the best coverage values were tested on live, intensively managed trees, whose crown volume was manually measured. Food dye E-102 was used to determine the spray deposition on artificial targets (10×10cm absorbent paper pieces), and WSP was used to evaluate spray coverage. The spray penetration and deposit homogeneity inside the canopy were also evaluated. Weather conditions during the field trial were monitored with a weather station. The results of the laboratory trial showed that the three best specific spray volumes were 0.08, 0.10, and 0.12Lm(-3), resulting in mean coverage values of approximately 30%. The ANOVA of the field trial results showed that the 0.12Lm(-3) was the optimal specific spray volume for isolated olive trees. This specific spray volume gave the highest mean deposits, the best efficiency (as measured by the greatest normalized deposit), the most favourable penetration and homogeneity, and the highest coverage values.

  19. Reduced cardiac volumes in chronic fatigue syndrome associate with plasma volume but not length of disease: a cohort study

    Science.gov (United States)

    Newton, Julia L; Finkelmeyer, Andreas; Petrides, George; Frith, James; Hodgson, Tim; Maclachlan, Laura; MacGowan, Guy; Blamire, Andrew M

    2016-01-01

    Objectives To explore potential mechanisms that underpin the cardiac abnormalities seen in chronic fatigue syndrome (CFS) using non-invasive cardiac impedance, red cell mass and plasma volume measurements. Methods Cardiac MR (MR) examinations were performed using 3 T Philips Intera Achieva scanner (Best, NL) in participants with CFS (Fukuda; n=47) and matched case-by-case controls. Total volume (TV), red cell volume (RCV) and plasma volume (PV) measurements were performed (41 CFS and 10 controls) using the indicator dilution technique using simultaneous 51-chromium labelling of red blood cells and 125-iodine labelling of serum albumin. Results The CFS group length of history (mean±SD) was 14±10 years. Patients with CFS had significantly reduced end-systolic and end-diastolic volumes together with reduced end-diastolic wall masses (all p<0.0001). Mean±SD RCV was 1565±443 mL with 26/41 (63%) having values below 95% of expected. PV was 2659±529 mL with 13/41 (32%) <95% expected. There were strong positive correlations between TV, RCV and PV and cardiac end-diastolic wall mass (all p<0.0001; r2=0.5). Increasing fatigue severity correlated negatively with lower PV (p=0.04; r2=0.2). There were no relationships between any MR or volume measurements and length of history, suggesting that deconditioning was unlikely to be the cause of these abnormalities. Conclusions This study confirms an association between reduced cardiac volumes and blood volume in CFS. Lack of relationship between length of disease, cardiac and plasma volumes suggests findings are not secondary to deconditioning. The relationship between plasma volume and severity of fatigue symptoms suggests a potential therapeutic target in CFS. PMID:27403329

  20. SU-E-J-79: Internal Tumor Volume Motion and Volume Size Assessment Using 4D CT Lung Data

    International Nuclear Information System (INIS)

    Purpose: To assess internal tumor volume change through breathing cycle and associated tumor motion using the 4DCT data. Methods: Respiration induced volume change through breathing cycle and associated motion was analyzed for nine patients that were scanned during the different respiratory phases. The examined datasets were the maximum and average intensity projections (MIP and AIP) and the 10 phases of the respiratory cycle. The internal target volume (ITV) was delineated on each of the phases and the planning target volume (PTV) was then created by adding setup margins to the ITV. Tumor motion through the phases was assessed using the acquired 4DCT dataset, which was then used to determine if the margins used for the ITV creation successfully encompassed the tumor in three dimensions. Results: Results showed that GTV motion along the superior inferior axes was the largest in all the cases independent of the tumor location and/or size or the use of abdomen compression. The extent of the tumor motion was found to be connected with the size of the GTV. The smallest GTVs exhibited largest motion vector independent of the tumor location. The motion vector size varied through the phases depending on the tumor size and location and it was smallest for phases 20 and 30. The smaller the volume of the delineated GTV, the greater its volume difference through the different respiratory phases was. The average GTV volume change was largest for the phases 60 and 70. Conclusion: Even if GTV is delineated using both AIP and MIP datasets, its motion extent will exceed the used margins especially for the very small GTV volumes. When the GTV size is less than 10 cc it is recommended to use fusion of the GTVs through all the phases to create the planning ITV

  1. Moving Target Defense

    CERN Document Server

    Jajodia, Sushil; Swarup, Vipin; Wang, Cliff; Wang, X Sean

    2011-01-01

    Moving Target Defense: Creating Asymmetric Uncertainty for Cyber Threats was developed by a group of leading researchers. It describes the fundamental challenges facing the research community and identifies new promising solution paths. Moving Target Defense which is motivated by the asymmetric costs borne by cyber defenders takes an advantage afforded to attackers and reverses it to advantage defenders. Moving Target Defense is enabled by technical trends in recent years, including virtualization and workload migration on commodity systems, widespread and redundant network connectivity, instr

  2. Target Window Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-11

    The target window design implemented and tested in experiments at ANL have performed without failure for the available beam of 6 mm FWHM on a 12 mm diameter target. However, scaling that design to a 25 mm diameter target size for a 12 mm FWHM beam has proven problematic. Combined thermal and mechanical (pressure induced) stresses and strains are too high to maintain the small coolant gaps and provide adequate fatigue lifetime.

  3. The ISOLDE target robots

    CERN Multimedia

    Maximilein Brice

    2002-01-01

    ISOLDE targets need to be changed frequently, around 80 times per year. The high radiation levels do not permit this to be done by human hands and the target changes are effected by 2 industrial robots (picture _01). On the left, in the distance, the front-end of the GPS (General Purpose Separator) is seen, while the HRS (High Resolution Separator) is at the right. Also seen are the doors to the irradiated-target storage.

  4. A Lumped-Parameter Subject-Specific Model of Blood Volume Response to Fluid Infusion.

    Science.gov (United States)

    Bighamian, Ramin; Reisner, Andrew T; Hahn, Jin-Oh

    2016-01-01

    This paper presents a lumped-parameter model that can reproduce blood volume response to fluid infusion. The model represents the fluid shift between the intravascular and interstitial compartments as the output of a hypothetical feedback controller that regulates the ratio between the volume changes in the intravascular and interstitial fluid at a target value (called "target volume ratio"). The model is characterized by only three parameters: the target volume ratio, feedback gain (specifying the speed of fluid shift), and initial blood volume. This model can obviate the need to incorporate complex mechanisms involved in the fluid shift in reproducing blood volume response to fluid infusion. The ability of the model to reproduce real-world blood volume response to fluid infusion was evaluated by fitting it to a series of data reported in the literature. The model reproduced the data accurately with average error and root-mean-squared error (RMSE) of 0.6 and 9.5% across crystalloid and colloid fluids when normalized by the underlying responses. Further, the parameters derived for the model showed physiologically plausible behaviors. It was concluded that this simple model may accurately reproduce a variety of blood volume responses to fluid infusion throughout different physiological states by fitting three parameters to a given dataset. This offers a tool that can quantify the fluid shift in a dataset given the measured fractional blood volumes. PMID:27642283

  5. Targeted Radionuclide Therapy

    Directory of Open Access Journals (Sweden)

    David Cheng

    2011-10-01

    Full Text Available Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose.

  6. Bayesian multiple target tracking

    CERN Document Server

    Streit, Roy L

    2013-01-01

    This second edition has undergone substantial revision from the 1999 first edition, recognizing that a lot has changed in the multiple target tracking field. One of the most dramatic changes is in the widespread use of particle filters to implement nonlinear, non-Gaussian Bayesian trackers. This book views multiple target tracking as a Bayesian inference problem. Within this framework it develops the theory of single target tracking, multiple target tracking, and likelihood ratio detection and tracking. In addition to providing a detailed description of a basic particle filter that implements

  7. Target Assembly Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Target Assembly Facility integrates new armor concepts into actual armored vehicles. Featuring the capability ofmachining and cutting radioactive materials, it...

  8. Targeting the tumor microenvironment

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, P.A.; Lee, G.Y.; Bissell, M.J.

    2006-11-07

    Despite some notable successes cancer remains, for the most part, a seemingly intractable problem. There is, however, a growing appreciation that targeting the tumor epithelium in isolation is not sufficient as there is an intricate mutually sustaining synergy between the tumor epithelial cells and their surrounding stroma. As the details of this dialogue emerge, new therapeutic targets have been proposed. The FDA has already approved drugs targeting microenvironmental components such as VEGF and aromatase and many more agents are in the pipeline. In this article, we describe some of the 'druggable' targets and processes within the tumor microenvironment and review the approaches being taken to disrupt these interactions.

  9. Optimal target VOI size for accurate 4D coregistration of DCE-MRI

    Science.gov (United States)

    Park, Brian; Mikheev, Artem; Zaim Wadghiri, Youssef; Bertrand, Anne; Novikov, Dmitry; Chandarana, Hersh; Rusinek, Henry

    2016-03-01

    Dynamic contrast enhanced (DCE) MRI has emerged as a reliable and diagnostically useful functional imaging technique. DCE protocol typically lasts 3-15 minutes and results in a time series of N volumes. For automated analysis, it is important that volumes acquired at different times be spatially coregistered. We have recently introduced a novel 4D, or volume time series, coregistration tool based on a user-specified target volume of interest (VOI). However, the relationship between coregistration accuracy and target VOI size has not been investigated. In this study, coregistration accuracy was quantitatively measured using various sized target VOIs. Coregistration of 10 DCE-MRI mouse head image sets were performed with various sized VOIs targeting the mouse brain. Accuracy was quantified by measures based on the union and standard deviation of the coregistered volume time series. Coregistration accuracy was determined to improve rapidly as the size of the VOI increased and approached the approximate volume of the target (mouse brain). Further inflation of the VOI beyond the volume of the target (mouse brain) only marginally improved coregistration accuracy. The CPU time needed to accomplish coregistration is a linear function of N that varied gradually with VOI size. From the results of this study, we recommend the optimal size of the VOI to be slightly overinclusive, approximately by 5 voxels, of the target for computationally efficient and accurate coregistration.

  10. Finding related functional neuroimaging volumes

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2004-01-01

    We describe a content-based image retrieval technique for finding related functional neuroimaging experiments by voxelization of sets of stereotactic coordinates in Talairach space, comparing the volumes and reporting related volumes in a sorted list. Voxelization is accomplished by convolving each...

  11. LLE Review Quarterly Report (January-March 2000). Volume 82

    Energy Technology Data Exchange (ETDEWEB)

    Radha, P. B. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics

    2000-03-01

    This volume of the LLE Review, covering the period January-March 2000, includes a report on OMEGA cryogenic target designs for the soon-to-be-commissioned OMEGA Cryogenic Target Handling System. R. P. J. Town, J. A. Delettrez, R. Epstein, V. N. Goncharov, P. W. McKenty, P. B. Radha, and S. Skupsky use two-dimensional hydrodynamic simulations in conjunction with a stability analysis model to study the performance of OMEGA cryogenic capsules. They show that these targets are energy-scaled from the NIF ignition designs and have similar 1-D behavior and stability properties. This similarity will facilitate the extrapolation of cryogenic target studies on OMEGA to ignition targets on the NIF. Other articles in this volume are: Imprint Reduction using an Intensity Spike in Omega Cryogenic Targets; Measurement of Preheat Due to Fast Electrons in Laser Implosions; Holographic Transmission Gratings for Spectral Dispersion; Laser Beam Smoothing Caused by the Small-Spatial-Scale B-Integral; Three-Dimensional Modeling of Capsule Implosions in OMEGA Tetrahedral Hohlraums; and, Nanoindentation Hardness of Particles Used in Magnetoheological finishing (MRF).

  12. Device overlay method for high volume manufacturing

    Science.gov (United States)

    Lee, Honggoo; Han, Sangjun; Kim, Youngsik; Kim, Myoungsoo; Heo, Hoyoung; Jeon, Sanghuck; Choi, DongSub; Nabeth, Jeremy; Brinster, Irina; Pierson, Bill; Robinson, John C.

    2016-03-01

    Advancing technology nodes with smaller process margins require improved photolithography overlay control. Overlay control at develop inspection (DI) based on optical metrology targets is well established in semiconductor manufacturing. Advances in target design and metrology technology have enabled significant improvements in overlay precision and accuracy. One approach to represent in-die on-device as-etched overlay is to measure at final inspection (FI) with a scanning electron microscope (SEM). Disadvantages to this approach include inability to rework, limited layer coverage due to lack of transparency, and higher cost of ownership (CoO). A hybrid approach is investigated in this report whereby infrequent DI/FI bias is characterized and the results are used to compensate the frequent DI overlay results. The bias characterization is done on an infrequent basis, either based on time or triggered from change points. On a per-device and per-layer basis, the optical target overlay at DI is compared with SEM on-device overlay at FI. The bias characterization results are validated and tracked for use in compensating the DI APC controller. Results of the DI/FI bias characterization and sources of variation are presented, as well as the impact on the DI correctables feeding the APC system. Implementation details in a high volume manufacturing (HVM) wafer fab will be reviewed. Finally future directions of the investigation will be discussed.

  13. Sparse PDF Volumes for Consistent Multi-Resolution Volume Rendering

    KAUST Repository

    Sicat, Ronell

    2014-12-31

    This paper presents a new multi-resolution volume representation called sparse pdf volumes, which enables consistent multi-resolution volume rendering based on probability density functions (pdfs) of voxel neighborhoods. These pdfs are defined in the 4D domain jointly comprising the 3D volume and its 1D intensity range. Crucially, the computation of sparse pdf volumes exploits data coherence in 4D, resulting in a sparse representation with surprisingly low storage requirements. At run time, we dynamically apply transfer functions to the pdfs using simple and fast convolutions. Whereas standard low-pass filtering and down-sampling incur visible differences between resolution levels, the use of pdfs facilitates consistent results independent of the resolution level used. We describe the efficient out-of-core computation of large-scale sparse pdf volumes, using a novel iterative simplification procedure of a mixture of 4D Gaussians. Finally, our data structure is optimized to facilitate interactive multi-resolution volume rendering on GPUs.

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

    International Nuclear Information System (INIS)

    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

  15. 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.

  16. Nano-oncologicals new targeting and delivery approaches

    CERN Document Server

    Alonso, Maria Jose

    2014-01-01

    This authoritative volume focuses on emerging technologies in cancer nano medicine, characterized by their multi-functionality and potential to address simultaneously diverse issues of clinical relevance in the treatment of cancer. The book consists of sixteen chapters divided into six sections: 1) Biological Barriers in Cancer; 2) Tumor Targeting; 3) Targeting the Immune System; 4) Gene Therapy; 5) Nano theranostics and 6) Translational Aspects of Nano-Oncologicals. The volume starts with an introduction describing the biological barriers associated with cancer therapy and highlighting ways

  17. The CNGS target

    CERN Multimedia

    Patrice Loïez

    2005-01-01

    The CERN Neutrinos to Gran Sasso (CNGS) target ‘magazine’ of five target units. Each unit contains a series of 10-cm long graphite rods distributed over a length of 2 m. It is designed to maximize the number of secondary particles produced and hence the number of neutrinos. One unit is used at a time to prevent over heating.

  18. Strategic Targeted Advertising

    NARCIS (Netherlands)

    A. Galeotti; J.L. Moraga-Gonzalez (José Luis)

    2003-01-01

    textabstractWe present a strategic game of pricing and targeted-advertising. Firms can simultaneously target price advertisements to different groups of customers, or to the entire market. Pure strategy equilibria do not exist and thus market segmentation cannot occur surely. Equilibria exhibit rand

  19. Targeted therapy in lymphoma

    Directory of Open Access Journals (Sweden)

    Cavalli Franco

    2010-11-01

    Full Text Available Abstract Discovery of new treatments for lymphoma that prolong survival and are less toxic than currently available agents represents an urgent unmet need. We now have a better understanding of the molecular pathogenesis of lymphoma, such as aberrant signal transduction pathways, which have led to the discovery and development of targeted therapeutics. The ubiquitin-proteasome and the Akt/mammalian target of rapamycin (mTOR pathways are examples of pathological mechanisms that are being targeted in drug development efforts. Bortezomib (a small molecule protease inhibitor and the mTOR inhibitors temsirolimus, everolimus, and ridaforolimus are some of the targeted therapies currently being studied in the treatment of aggressive, relapsed/refractory lymphoma. This review will discuss the rationale for and summarize the reported findings of initial and ongoing investigations of mTOR inhibitors and other small molecule targeted therapies in the treatment of lymphoma.

  20. Volumetric Spectroscopic Imaging of Glioblastoma Multiforme Radiation Treatment Volumes

    International Nuclear Information System (INIS)

    Purpose: Magnetic resonance (MR) imaging and computed tomography (CT) are used almost exclusively in radiation therapy planning of glioblastoma multiforme (GBM), despite their well-recognized limitations. MR spectroscopic imaging (MRSI) can identify biochemical patterns associated with normal brain and tumor, predominantly by observation of choline (Cho) and N-acetylaspartate (NAA) distributions. In this study, volumetric 3-dimensional MRSI was used to map these compounds over a wide region of the brain and to evaluate metabolite-defined treatment targets (metabolic tumor volumes [MTV]). Methods and Materials: Volumetric MRSI with effective voxel size of ∼1.0 mL and standard clinical MR images were obtained from 19 GBM patients. Gross tumor volumes and edema were manually outlined, and clinical target volumes (CTVs) receiving 46 and 60 Gy were defined (CTV46 and CTV60, respectively). MTVCho and MTVNAA were constructed based on volumes with high Cho and low NAA relative to values estimated from normal-appearing tissue. Results: The MRSI coverage of the brain was between 70% and 76%. The MTVNAA were almost entirely contained within the edema, and the correlation between the 2 volumes was significant (r=0.68, P=.001). In contrast, a considerable fraction of MTVCho was outside of the edema (median, 33%) and for some patients it was also outside of the CTV46 and CTV60. These untreated volumes were greater than 10% for 7 patients (37%) in the study, and on average more than one-third (34.3%) of the MTVCho for these patients were outside of CTV60. Conclusions: This study demonstrates the potential usefulness of whole-brain MRSI for radiation therapy planning of GBM and revealed that areas of metabolically active tumor are not covered by standard RT volumes. The described integration of MTV into the RT system will pave the way to future clinical trials investigating outcomes in patients treated based on metabolic information

  1. Minivoids in the Local Volume

    CERN Document Server

    Tikhonov, A V

    2006-01-01

    We consider a sphere of 7.5 Mpc radius, which contains 355 galaxies with accurately measured distances, to detect the nearest empty volumes. Using a simple void detection algorithm, we found six large (mini)voids in Aquila, Eridanus, Leo, Vela, Cepheus and Octans, each of more than 30 Mpc^3. Besides them, 24 middle-size "bubbles" of more than 5 Mpc^3 volume are detected, as well as 52 small "pores". The six largest minivoids occupy 58% of the considered volume. Addition of the bubbles and pores to them increases the total empty volume up to 75% and 81%, respectively. The detected local voids look like oblong potatoes with typical axial ratios b/a = 0.75 and c/a = 0.62 (in the triaxial ellipsoide approximation). Being arranged by the size of their volume, local voids follow power law of volumes-rankes dependence. A correlation Gamma-function of the Local Volume galaxies follows a power low with a formally calculated fractal dimension D = 1.5. We found that galaxies surrounding the local minivoids do not differ...

  2. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, F; Christensen, N J;

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

  3. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Frandsen, Henrik Lund; Christensen, N J;

    1991-01-01

    -induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

  4. Cell swelling and volume regulation

    DEFF Research Database (Denmark)

    Hoffmann, Else Kay

    1992-01-01

    The extracellular space in the brain is typically 20% of the tissue volume and is reduced to at least half its size under conditions of neural insult. Whether there is a minimum size to the extracellular space was discussed. A general model for cell volume regulation was presented, followed...... by a discussion on how many of the generally involved mechanisms are identified in neural cells and (or) in astrocytes. There seems to be clear evidence suggesting that parallel K+ and Cl- channels mediate regulatory volume decrease in primary cultures of astrocytes, and a stretch-activated cation channel has...

  5. Dictionary Based Segmentation in Volumes

    DEFF Research Database (Denmark)

    Emerson, Monica Jane; Jespersen, Kristine Munk; Jørgensen, Peter Stanley;

    2015-01-01

    We present a method for supervised volumetric segmentation based on a dictionary of small cubes composed of pairs of intensity and label cubes. Intensity cubes are small image volumes where each voxel contains an image intensity. Label cubes are volumes with voxelwise probabilities for a given...... label. The segmentation process is done by matching a cube from the volume, of the same size as the dictionary intensity cubes, to the most similar intensity dictionary cube, and from the associated label cube we get voxel-wise label probabilities. Probabilities from overlapping cubes are averaged and...

  6. Dictionary Based Segmentation in Volumes

    DEFF Research Database (Denmark)

    Emerson, Monica Jane; Jespersen, Kristine Munk; Jørgensen, Peter Stanley;

    2015-01-01

    We present a method for supervised volumetric segmentation based on a dictionary of small cubes composed of pairs of intensity and label cubes. Intensity cubes are small image volumes where each voxel contains an image intensity. Label cubes are volumes with voxelwise probabilities for a given...... label. The segmentation process is done by matching a cube from the volume, of the same size as the dictionary intensity cubes, to the most similar intensity dictionary cube, and from the associated label cube we get voxel-wise label probabilities. Probabilities from overlapping cubes are averaged...

  7. Particles in small volume injections.

    Science.gov (United States)

    Taylor, S A; Spence, J

    1983-12-01

    The level of particulate contamination in small volume injections has been examined using the light blockage (HIAC) and electrical sensing zone (Coulter counter) techniques, the HIAC system being found to be the more suitable. Particle counts on the same batch of injection showed a large and variable difference between the HIAC and the Coulter counter results, especially below 5 micron. None of the injections examined complied with the British Pharmacopoeia limits for particulates in large volume parenterals, suggesting the unsuitability of the limits for small volume parenterals. PMID:6141237

  8. Nuclear target development

    Energy Technology Data Exchange (ETDEWEB)

    Greene, J.P.; Thomas, G.E.

    1995-08-01

    The Physics Division operates a target development laboratory that produces thin foil targets needed for experiments performed at the ATLAS and Dynamitron accelerators. Targets are not only produced for the Physics Division but also for other divisions and occasionally for other laboratories and universities. In the past year, numerous targets were fabricated by vacuum evaporation either as self-supporting foils or on various substrates. Targets produced included Ag, Au, {sup 10,11}B, {sup 138}Ba, Be, {sup 12}C, {sup 40}Ca, {sup 116}Cd, {sup 155,160}Gd, {sup 76}Ge, In, LID, {sup 6}LiH, Melamine, Mg, {sup 142,150}Nd, {sup 58}Ni, {sup 206,208}Pb, {sup 194}Pt, {sup 28}Si, {sup 144,148}Sm, {sup 120,122,124}Sn, Ta, {sup 130}Te, ThF{sub 4}, {sup 46,50}Ti, TiH, U, UF{sub 4}, {sup 182}W and {sup 170}Yb. Polypropylene and aluminized polypropylene, along with metallized Mylar were produced for experiments at ATLAS. A number of targets of {sup 11}B of various thickness were made for the DEP 2-MeV Van de Graff accelerator. An increased output of foils fabricated using our small rolling mill included targets of Au, C, {sup 50}Cr, Cu, {sup 155,160}Gd, Mg, {sup 58}Ni, {sup 208}Pb, {sup 105,110}Pd. Sc, Ti, and {sup 64,66}Zn.

  9. FT coverage and UK target price run-ups

    OpenAIRE

    Siganos, Antonios; Papa, Marco

    2015-01-01

    We focus on the market expectation hypothesis to explain the increase in share prices and trading volume of target firms before their merger announcements that have conventionally been attributed to either insider trading or market expectation. We use Financial Times (FT) coverage as a proxy of merger expectation and search for relevant articles for 783 UK target firms between 1998 and 2010. We identify a total of 1049 rumour articles and find that the FT market expectation proxy explains a s...

  10. Volume Ignition via Time-like Detonation in Pellet Fusion

    CERN Document Server

    Csernai, L P

    2015-01-01

    Relativistic fluid dynamics and the theory of relativistic detonation fronts are used to estimate the space-time dynamics of the burning of the D-T fuel in Laser driven pellet fusion experiments. The initial "High foot" heating of the fuel makes the compressed target transparent to radiation, and then a rapid ignition pulse can penetrate and heat up the whole target to supercritical temperatures in a short time, so that most of the interior of the target ignites almost simultaneously and instabilities will have no time to develop. In these relativistic, radiation dominated processes both the interior, time-like burning front and the surrounding space-like part of the front will be stable against Rayleigh-Taylor instabilities. To achieve this rapid, volume ignition the pulse heating up the target to supercritical temperature should provide the required energy in less than ~ 10 ps.

  11. AA antiproton production target

    CERN Multimedia

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing of stainless steel. At the entrance to the target assembly was a scintillator screen, imprinted with circles every 5 mm in radius, which allowed to precisely aim the 26 GeV high-intensity proton beam from the PS onto the centre of the target rod. The scintillator screen was a 1 mm thick plate of Cr-doped alumina. See also 7903034 and 7905091.

  12. Internal polarized targets

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, E.R.; Coulter, K.; Gilman, R.; Holt, R.J.; Kowalczyk, R.S.; Napolitano, J.; Potterveld, D.H.; Young, L. (Argonne National Lab., IL (USA)); Mishnev, S.I.; Nikolenko, D.M.; Popov, S.G.; Rachek, I.A.; Temnykh, A.B.; Toporkov, D.K.; Tsentalovich, E.P.; Wojtsekhowski, B.B. (AN SSSR, Novosibirsk (USSR). Inst. Yadernoj Fiziki)

    1989-01-01

    Internal polarized targets offer a number of advantages over external targets. After a brief review of the basic motivation and principles behind internal polarized targets, the technical aspects of the atomic storage cell will be discussed in particular. Sources of depolarization and the means by which their effects can be ameliorated will be described, especially depolarization by the intense magnetic fields arising from the circulating particle beam. The experience of the Argonne Novosibirsk collaboration with the use of a storage cell in a 2 GeV electron storage ring will be the focus of this technical discussion. 17 refs., 11 figs.

  13. STIS target acquisition

    Science.gov (United States)

    Kraemer, Steve; Downes, Ron; Katsanis, Rocio; Crenshaw, Mike; McGrath, Melissa; Robinson, Rich

    1997-01-01

    We describe the STIS autonomous target acquisition capabilities. We also present the results of dedicated tests executed as part of Cycle 7 calibration, following post-launch improvements to the Space Telescope Imaging Spectrograph (STIS) flight software. The residual pointing error from the acquisitions are < 0.5 CCD pixels, which is better than preflight estimates. Execution of peakups show clear improvement of target centering for slits of width 0.1 sec or smaller. These results may be used by Guest Observers in planning target acquisitions for their STIS programs.

  14. 10 CFR 63.332 - Representative volume.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Representative volume. 63.332 Section 63.332 Energy... Protection Standards § 63.332 Representative volume. (a) The representative volume is the volume of ground... radionuclides released from the Yucca Mountain disposal system that will be in the representative volume....

  15. Organ volume estimation using SPECT

    CERN Document Server

    Zaidi, H

    1996-01-01

    Knowledge of in vivo thyroid volume has both diagnostic and therapeutic importance and could lead to a more precise quantification of absolute activity contained in the thyroid gland. In order to improve single-photon emission computed tomography (SPECT) quantitation, attenuation correction was performed according to Chang's algorithm. The dual-window method was used for scatter subtraction. We used a Monte Carlo simulation of the SPECT system to accurately determine the scatter multiplier factor k. Volume estimation using SPECT was performed by summing up the volume elements (voxels) lying within the contour of the object, determined by a fixed threshold and the gray level histogram (GLH) method. Thyroid phantom and patient studies were performed and the influence of 1) fixed thresholding, 2) automatic thresholding, 3) attenuation, 4) scatter, and 5) reconstruction filter were investigated. This study shows that accurate volume estimation of the thyroid gland is feasible when accurate corrections are perform...

  16. Human gallbladder pressure and volume

    DEFF Research Database (Denmark)

    Borly, L; Højgaard, L; Grønvall, S;

    1996-01-01

    influenced by respiration (n = 8) and the pressure seems to be higher in the sitting position than in the supine position (n = 5). Cystic duct opening pressure was 10.4, 11.2 and 16.8 mmHg (n = 3). Pressure-volume responses showed that the GB up to a certain volume could accommodate increases in intraluminal...... volume with only slight changes in intraluminal pressure (n = 4). Except for the zero drift, this piece of equipment seemed to fulfil the requirements of being able to measure pressure in the GB. In vivo measurements showed a good clinical reproducibility of the method, and also that respiration...... and patient posture influenced the pressure measurements. Further, a GB pressure-volume relationship was demonstrated, and the possibility of a cystic duct opening pressure was described....

  17. On algebraic volume density property

    OpenAIRE

    Kaliman, Shulim; Kutzschebauch, Frank

    2012-01-01

    A smooth affine algebraic variety $X$ equipped with an algebraic volume form $\\omega$ has the algebraic volume density property (AVDP) if the Lie algebra generated by completely integrable algebraic vector fields of $\\omega$-divergence zero coincides with the space of all algebraic vector fields of $\\omega$-divergence zero. We develop an effective criterion of verifying whether a given $X$ has AVDP. As an application of this method we establish AVDP for any homogeneous space $X=G/R$ that admi...

  18. Target Price Accuracy

    Directory of Open Access Journals (Sweden)

    Alexander G. Kerl

    2011-04-01

    Full Text Available This study analyzes the accuracy of forecasted target prices within analysts’ reports. We compute a measure for target price forecast accuracy that evaluates the ability of analysts to exactly forecast the ex-ante (unknown 12-month stock price. Furthermore, we determine factors that explain this accuracy. Target price accuracy is negatively related to analyst-specific optimism and stock-specific risk (measured by volatility and price-to-book ratio. However, target price accuracy is positively related to the level of detail of each report, company size and the reputation of the investment bank. The potential conflicts of interests between an analyst and a covered company do not bias forecast accuracy.

  19. Targeted therapies for cancer

    Science.gov (United States)

    ... to be untrue. Possible side effects from targeted therapies include: Diarrhea Liver problems Skin problems such as rash, dry skin, and nail changes Problems with blood clotting and wound healing High blood pressure As with any treatment, you ...

  20. LLE Review Quarterly Report (October - December 2007). Volume 113

    Energy Technology Data Exchange (ETDEWEB)

    Zuegel, Jonathan D. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics

    2007-12-01

    This volume of the LLE Review, covering October–December 2007, features “High-Intensity Laser–Plasma Interactions in the Refluxing Limit,” by P. M. Nilson, W. Theobald, J. Myatt, C. Stoeckl, M. Storm, O. V. Gotchev, J. D. Zuegel, R. Betti, D. D. Meyerhofer, and T. C. Sangster. In this article (p. 1), the authors report on target experiments using the Multi-Terawatt (MTW) Laser Facility to study isochoric heating of solid-density targets by fast electrons produced from intense, short-pulse laser irradiation. Electron refluxing occurs due to target-sheath field effects and contains most of the fast electrons within the target volume. This efficiently heats the solid-density plasma through collisions. X-ray spectroscopic measurements of absolute Kα (x-radiation) photon yields and variations of the Kβ/Kα b emission ratio both indicate that laser energy couples to fast electrons with a conversion efficiency of approximately 20%. Bulk electron temperatures of at least 200 eV are inferred for the smallest mass targets.

  1. Preliminary study of the internal margin of the gross tumor volume in thoracic esophageal cancer

    International Nuclear Information System (INIS)

    Purpose. - To measure the displacement of the tumor of the gross tumor volume (GTV) of thoracic esophageal cancer in the calm states of end-inspiration and end-expiration for determining the internal margin of the GTV (IGTV). Methods. - Twenty-two patients with thoracic esophageal cancer who were unable to undergo surgery were identified in our hospital. The patients received radiotherapy. By using 16-slice spiral computed tomography (CT), we acquired the calm states of end-inspiration and end-expiration. The displacement and volume changes in tumor target volume were measured, and the changes were analyzed to determine if these were associated with the tidal volume and the location and length of the target volume V. In the end, we analyzed the displacement of tumor target volume and calculated the internal margin of the GTV by empirical formula. Results. - The average tidal volume was 463.6 ml. The average GTV at end-inspiration was 33.3 ml and at end-expiration was 33.35 ml. Three was not any significant between two groups (T -0.034, P > 0.05). The IGTV (X-axis direction) was 3.09 mm for the right sector and 4.08 mm for the left border; the IGTV (Z-axis direction) was 3.96 mm for the anterior border and 2.83 mm for the posterior border; and the IGTV (Y-axis direction) was 7.31 mm for the upper boundary (head direction) and 10.16 mm for the lower boundary (feet direction). The motion of the GTV showed no significant correlation with the tidal volume of patients and the length of the tumor, but in relation to the tumor location, the displacement of the lower thoracic and the middle thoracic target volumes occurred in the direction of the anterior and right, which were not significantly different (T = 0.859, 0.229, P > 0.05) The significant differences were observed for the other directions (P < 0.05). Conclusions. - Because of respiratory and organ movements, the displacement of the tumor target volume was different in all directions. Therefore, we recommend that

  2. LLE Review quarterly report, April--June 1993. Volume 55

    Energy Technology Data Exchange (ETDEWEB)

    Hutchison, R.J. [ed.

    1993-10-01

    This volume of the LLE Review, covering the period April--June 1993, contains articles on spectral features from argon-filled target implosions on OMEGA, and on the theory of an implicit difference scheme for the Fokker-Planck equation. The advanced technology section includes reports on a novel polymer liquid-crystal wave plate and a new scheme for phase conversion of the OMEGA Upgrade beams that results in greater, smoother energy deposition on fusion targets. Finally, reports on the as-designed configuration of the OMEGA newly configured glass development laser system are summarized.

  3. LLE Review Quarterly Report (October-December 1990). Volume 45

    Energy Technology Data Exchange (ETDEWEB)

    Epperlein, E. M. [Univ. of Rochester, NY (United States)

    1990-12-01

    This volume of the LLE Review, covering the period October-December 1990, contains descriptions of a new phase-conversion technique designed to improve irradiation uniformity, a report on the interpretation of highdensity implosion experiments of argon-filled targets, and an article on the use of absorption spectroscopy to diagnose compressed target layers. The section on advanced technology has a report on the application of KTP crystals as electro-optic amplitude modulators, and describes the use of chirped-pulse technology to measure X(3) by nearly degenerate four-wave mixing. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  4. Optimising stroke volume and oxygen delivery in abdominal aortic surgery

    DEFF Research Database (Denmark)

    Bisgaard, J; Gilsaa, T; Rønholm, E;

    2012-01-01

    BACKGROUND: Post-operative complications after open elective abdominal aortic surgery are common, and individualised goal-directed therapy may improve outcome in high-risk surgery. We hypothesised that individualised goal-directed therapy, targeting stroke volume and oxygen delivery, can reduce...... group (P = 0.01). However, the number of complications per patient or length of stay in the intensive care unit or hospital did not differ between the groups. CONCLUSION: Perioperative individualised goal-directed therapy targeting stroke volume and oxygen delivery did not affect post...... complications and minimise length of stay in intensive care unit and hospital following open elective abdominal aortic surgery. METHODS: Seventy patients scheduled for open elective abdominal aortic surgery were randomised to individualised goal-directed therapy or conventional therapy. In the intervention...

  5. Liposomes for cardiovascular targeting.

    Science.gov (United States)

    Levchenko, Tatyana S; Hartner, William C; Torchilin, Vladimir P

    2012-04-01

    Liposome-based pharmaceuticals used within the cardiovascular system are reviewed in this article. The delivery of diagnostic and therapeutic agents by plain liposomes and liposomes with surface-attached targeting antibodies or polyethylene glycol to prolong their circulation time and accumulation at vascular injuries, ischemic zones or sites of thrombi are also discussed. An overview of the advantages and disadvantages of liposome-mediated in vitro, ex vivo and in vivo targeting is presented, including discussion of the targeting of liposomes to pathological sites on the blood vessel wall and a description of liposomes that can be internalized by endothelial cells. Diagnostic liposomes used to target myocardial infarction and the relative importance of liposome size, targetability of immunoliposomes and prolonged circulation time on the efficiency of sealing hypoxia-induced plasma membrane damage to cardiocytes are discussed as a promising approach for therapy. The progress in the use of targeted liposomal plasmids for the transfection of hypoxic cardiomyocytes and myocardium is presented. Stent-mediated liposomal-based drug delivery is also reviewed briefly. PMID:22834079

  6. Radar target detection simulation

    Directory of Open Access Journals (Sweden)

    Tarig Ibrahim Osman

    2014-12-01

    Full Text Available Standard radar detection process requires that the sensor output is compared to a predetermined threshold. The threshold is selected based on a-priori knowledge available and/or certain assumptions. However, any knowledge and/or assumptions become in adequate due to the presence of multiple targets with varying signal return and usually non stationary background. Thus, any predetermined threshold may result in either increased false alarm rate or increased track loss. Even approaches where the threshold is adaptively varied will not perform well in situations when the signal return from the target of interest is too low compared to the average level of the background .Track-before-detect techniques eliminate the need for a detection threshold and provide detecting and tracking targets with lower signal-to-noise ratios than standard methods. However, although trackbefore-detect techniques eliminate the need for detection threshold at sensor's signal processing stage, they often use tuning thresholds at the output of the filtering stage .This paper presents a computerized simulation model for target detection process. Moreover, the proposed model method is based on the target motion models, the output of the detection process can easily be employed for maneuvering target tracking.

  7. An ISOLDE target unit

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    A good dozen different targets are available for ISOLDE, made of different materials and equipped with different kinds of ion-sources, according to the needs of the experiments. Each separator (GPS: general purpose; HRS: high resolution) has its own target. Because of the high radiation levels, robots effect the target changes, about 80 times per year. In the standard unit shown in picture _01, the target is the cylindrical object in the front. It contains uranium-carbide kept at a temperature of 2200 deg C, necessary for the isotopes to be able to escape. At either end, one sees the heater current leads, carrying 700 A. The Booster beam, some 3E13 protons per pulse, enters the target from left. The evaporated isotope atoms enter a hot-plasma ion source (the black object behind the target). The whole unit sits at 60 kV potential (pulsed in synchronism with the arrival of the Booster beam) which accelerates the ions (away from the viewer) towards one of the 2 separators.

  8. LLE Review Quarterly Report (January-March 1988). Volume 34

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, J. [Univ. of Rochester, NY (United States)

    1988-03-01

    This volume of the LLE Review, covering the period January-March 1988, contains articles on the spectra of scattered laser radiation from laser-produced plasmas and on the bounce coating of ablation layers on fusion targets. The advanced technology section has reports on a novel technique for characterizing surface breakdown on semiconductor devices and on a versatile alexandrite regenerative amplifier. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  9. Insular volume reduction in schizophrenia.

    Science.gov (United States)

    Saze, Teruyasu; Hirao, Kazuyuki; Namiki, Chihiro; Fukuyama, Hidenao; Hayashi, Takuji; Murai, Toshiya

    2007-12-01

    Structural and functional abnormalities of the insular cortex have been reported in patients with schizophrenia. Most studies have shown that the insular volumes in schizophrenia patients are smaller than those of healthy people. As the insular cortex is functio-anatomically divided into anterior and posterior subdivisons, recent research is focused on uncovering a specific subdivisional abnormality of the insula in patients with schizophrenia. A recent ROI-based volumetric MRI study demonstrated specific left anterior insular volume reduction in chronic schizophrenia patients (Makris N, Goldstein J, Kennedy D, Hodge S, Caviness V, Faraone S, Tsuang M, Seidman L (2006) Decreased volume of left and total anterior insular lobule in schizophrenia. Schizophr Res 83:155-171). On the other hand, our VBM-based volumetric study revealed a reduction in right posterior insular volume (Yamada M, Hirao K, Namiki C, Hanakawa T, Fukuyama H, Hayashi T, Murai T (2007) Social cognition and frontal lobe pathology in schizophrenia: a voxel-based morphometric study. NeuroImage 35:292-298). In order to address these controversial results, ROI-based subdivisional volumetry was performed using the MRI images from the same population we analyzed in our previous VBM-study. The sample group comprised 20 schizophrenia patients and 20 matched healthy controls. Patients with schizophrenia showed a global reduction in insular gray matter volumes relative to healthy comparison subjects. In a simple comparison of the volumes of each subdivision between the groups, a statistically significant volume reduction in patients with schizophrenia was demonstrated only in the right posterior insula. This study suggests that insular abnormalities in schizophrenia would include anterior as well as posterior parts. Each subdivisional abnormality may impact on different aspects of the pathophysiology and psychopathology of schizophrenia; these relationships should be the focus of future research.

  10. The Sinuous Target

    Energy Technology Data Exchange (ETDEWEB)

    Zwaska, R. [Fermilab

    2015-06-01

    We report on the concept for a target material comprised of a multitude of interlaced wires of small dimension. This target material concept is primarily directed at high-power neutrino targets where the thermal shock is large due to small beam sizes and short durations; it also has applications to other high-power targets, particularly where the energy deposition is great or a high surface area is preferred. This approach ameliorates the problem of thermal shock by engineering a material with high strength on the micro-scale, but a very low modulus of elasticity on the meso-scale. The low modulus of elasticity is achieved by constructing the material of spring-like wire segments much smaller than the beam dimension. The intrinsic bends of the wires will allow them to absorb the strain of thermal shock with minimal stress. Furthermore, the interlaced nature of the wires provides containment of any segment that might become loose. We will discuss the progress on studies of analogue materials and fabrication techniques for sinuous target materials.

  11. Production Target Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-07-28

    The Northstar 99Mo production target, a cylindrical length of 100Mo rod, has evolved considerably since its first conception.  The cylinder was very early sliced into disks to increase the heat transfer area, first to 1 mm thick disks then to the current 0.5 mm thick.  The coolant was changed early in the target development from water to helium to eliminate corrosion and dissolution.  The diameter has increased from initially 6 mm to 12 mm, the current diameter of the test target now at ANL, to nominally 28 mm (26-30.6 mm, depending upon optimal beam spot size and shape).  The length has also changed to improve the production to cost ratio, so now the target is nominally 41 mm long (excluding coolant gaps between disks), and irradiated on both ends.  This report summarizes the current status of the plant target design.

  12. GTV and CTV in radiation therapy: lung cancer; Volume tumoral macroscopique et volume-cible anatomoclinique en radiotherapie: cancer bronchique

    Energy Technology Data Exchange (ETDEWEB)

    Mornex, F.; Chapet, O.; Sentenac, I. [Centre Hospitalier Lyon-Sud, Dept. de Radiotherapie Oncologie, EA 643, 69 - Pierre Benite (France); Loubeyre, P. [Centre Hospitalier Lyon-Sud, Dept. de Radiologie, 69 - Pierre Benite (France); Giraud, P. [Institut Curie, Dept. d' Oncologie Radiotherapie, 75 - Paris (France); Van Houtte, P. [Institut Jules Bordet, Dept. de Radiotherapie, Bruxelles (Belgium); Bonnette, P. [Hopital Foch, Chirurgie Thoracique, 92 - Suresnes (France)

    2001-10-01

    Radiotherapy plays a major role as a curative treatment of various stages non-small cell lung cancers (NSCLC): as an exclusive treatment in curative attempt for patients with unresectable stages I and II; as a preoperative treatment, which is often associated with chemotherapy, for patients with surgically stage IIIA NSCLC in clinical trials; in association with chemotherapy for unresectable stages IIIA and IIIB patients. Currently, three-dimensional conformal radiotherapy allows for some dose escalation, increasing radiation quality. However, the high inherent conformality of this radiotherapy technique requires a rigorous approach and an optimal quality of the preparation throughout the treatment procedure and specifically of the accurate definition of the safety margins (GTV, CTV...). Different questions remain specific to lung cancers: 1) Despite the absence of randomized trials, the irradiated lymph nodes volume should be only, for the majority of the authors, the visible macroscopically involved lymph nodal regions. However, local control remains low and solid arguments suggest the poor local control is due to an insufficient delivered dose. Therefore the goal of radiotherapy, in this particular location, is to improve local control by increasing the dose until the maximum normal tissue tolerance is achieved, which essentially depends on the dose to the organs at risk (OAR) and specifically for the lung, the esophagus and the spinal cord. For this reason, the irradiated volume should be as tiny as possible, leading to not including the macroscopically uninvolved lymph nodes regions in prophylactic view in the target volume; 2) The lung is one of the rare organs with extensive motion within the body, making lung tumors difficult to treat. This particular point is not specifically considered in the GTV and CTV definitions but it is important enough to be noted; 3) When radiation therapy starts after a good response to chemotherapy, the residual tumoral volume

  13. Inflation Forecast Targeting: Implementing and Monitoring Inflation Targets

    OpenAIRE

    Lars E.O. Svensson

    1996-01-01

    Inflation targeting is shown to imply inflation forecast targeting: the central bank's inflation forecast becomes an intermediate target. Inflation forecast targeting simplifies both implementing and monitoring of monetary policy. The inflation forecast is actually an ideal intermediate target: it is most correlated with the goal, easier to control than the goal, more observable than the goal, and very transparent. Money growth targeting generally leads to higher inflation variability than in...

  14. [Radiotherapy of cancers of the pancreas and extrahepatic biliary tree. Gross tumor volume (GTV). Clinical target volume (CTV)].

    Science.gov (United States)

    Atlan, D; Mornex, F

    2001-10-01

    Anatomical data of pancreas, biliary tree, regional lymph nodes is required to define GTV and CTV. In case of postoperative irradiation, CTV is designed in collaboration with radiation oncologist and surgeon oncologist. For exclusive radiotherapy, endodigestive ultrasonography, CT scan and MRI could help radiation oncologist defining GTV. Although, accuracy of all the imaging techniques in past years remains poor. Currently, no available literature is published regarding security margins for the definition of CTV. Therefore, recommendations according to clinical experience are proposed. PMID:11715305

  15. Phoenix Color Targets

    Science.gov (United States)

    2008-01-01

    These images of three Phoenix color targets were taken on sols 1 and 2 by the Surface Stereo Imager (SSI) on board the Phoenix lander. The bottom target was imaged in approximate color (SSI's red, green, and blue filters: 600, 530, and 480 nanometers), while the others were imaged with an infrared filter (750 nanometers). All of them will be imaged many times over the mission to monitor the color calibration of the camera. The two at the top show grains 2 to 3 millimeters in size that were likely lifted to the Phoenix deck during landing. Each of the large color chips on each target contains a strong magnet to protect the interior material from Mars' magnetic dust. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. Targeted Phototherapy (newer phototherapy

    Directory of Open Access Journals (Sweden)

    Zonunsanga

    2015-04-01

    Full Text Available Conventional phototherapy uses a whole body cabinet or body part machine such as hand, foot or scalp machines. They have many disadvantages due to which new phototherapy technique was then developed to overcome this situation. This new technique is called targeted phototherapy which includes excimer laser, intense pulse light system (IPL, photodynamic therapy and ultraviolet (UV light source with a sophisticated delivery system which is easy to be operated by hands. The mechanisms of action of targeted phototherapy systems are similar to those in conventional UVB/UVA therapy. They have many advantages like less chances of side effects, avoidance of exposure of unnecessary sites, faster response, shortening of the duration of treatments. But they have disadvantages like high costs and inability to use for extensive areas. This review article discusses targeted phototherapy in considerable to the mechanism of actions and advantages and disadvantages in comparison to the conventional phototherapy.

  17. Setting reference targets

    International Nuclear Information System (INIS)

    Reference Targets are used to represent virtual quantities like the magnetic axis of a magnet or the definition of a coordinate system. To explain the function of reference targets in the sequence of the alignment process, this paper will first briefly discuss the geometry of the trajectory design space and of the surveying space, then continue with an overview of a typical alignment process. This is followed by a discussion on magnet fiducialization. While the magnetic measurement methods to determine the magnetic centerline are only listed (they will be discussed in detail in a subsequent talk), emphasis is given to the optical/mechanical methods and to the task of transferring the centerline position to reference targets

  18. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    hill, amanda; Leinikka Dall, Ole; Andersen, Frits Møller

    2014-01-01

    Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22......% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses...... how the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish...

  19. Symmetry Breaking in Finite Volume

    Institute of Scientific and Technical Information of China (English)

    LIU Chuan

    2000-01-01

    Spontaneous symmetry breaking is a cooperative phenomenon for systems with infinitely many degrees of freedom and it plays an essential role in quantum field theories. Lattice O(N) model is studied within the Hamiltonian approach using an adiabatic approximation. It is shown that the low-lying spectrum of the system in the broken phase can be understood by using the adiabatic, or Born-Oppenheimer approximation, which turns out to become an expansion in the inverse power of volume. In the infinite volume limit, the symmetry is broken while in the finite volume the slow rotation of the zero-momentum mode restores the symmetry and gives rise to the rotator spectrum, which has been observed in realistic Monte Carlo simulations.

  20. AA antiproton production target

    CERN Multimedia

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long (actually a row of 11 rods, each 1 cm long) and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing made of stainless steel. The casing had fins for forced-air cooling. In this picture, the 26 GeV high-intensity beam from the PS enters from the right, where a scintillator screen, with circles every 5 mm in radius, permits precise aim at the target centre. See also 7903034 and 7905094.

  1. Targeting peroxiredoxins against leukemia.

    Science.gov (United States)

    Liu, Chuan-Xu; Zhou, Hu-Chen; Yin, Qian-Qian; Wu, Ying-Li; Chen, Guo-Qiang

    2013-01-15

    Peroxiredoxins (Prx), a family of small non-seleno peroxidases, are important regulators for cellular reactive oxygen species (ROS), which contribute to many signaling pathways and pathogenesis of diseases. Targeting redox homeostasis is being developed as a promising therapeutic strategy for many diseases such as cancers. This mini-review attempts to focus on our recent discoveries on adenanthin as the first natural molecule to specifically target the resolving cysteines of Prx I and Prx II and thus inhibit their peroxidase activities, and its role in differentiation induction in vitro and in vivo of acute myeloid leukemic cells.

  2. Gas volume contents within a container, smart volume instrument

    Science.gov (United States)

    Kelley, Anthony R. (Inventor); Van Buskirk, Paul D. (Inventor)

    2008-01-01

    A method for determining the volume of an incompressible gas in a system including incompressible substances in a zero-gravity environment. The method includes inducing a volumetric displacement within a container and measuring the resulting pressure change. From this data, the liquid level can be determined.

  3. Plasmas physic. Volume 1. Physique des Plasmas. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Delcroix, J.L. (Paris-11 Univ., 91 - Orsay (France)); Bers, A. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Electrical Engineering Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center Massachusetts Inst. of Tech., Cambridge, MA (United States). Research Lab. of Electronics)

    1994-01-01

    An introduction to plasmas physic is done with qualitative and elementary calculus. Trajectory in a magnetic field, elastic and inelastic collisions, macroscopic description of low ionized gases, an hydrodynamic description of waves on electrons beams, and of instabilities in plasmas current are the main fields covered by this first volume. (A.B.). 369 refs., figs., tabs.

  4. Planimetric determination of lung volume

    International Nuclear Information System (INIS)

    The total volume of the lungs was determined by digital planimetry in 102 patients with emphysema and 33 normal controls aged between 30 and 79 years. The results were compared with the findings obtained from spirometric measurements. Mean values showed a significant relationship to age, body size and body surface. Planimetrically determined lung volume did not show a linear relationship with age, but increased after 60 years. Beyong 60 years, spirometric findings were lower because of an increase in the number of patients with emphysema. The results have shown that digital planimetry is a useful addition to spirometry. (orig.)

  5. Large volume cryogenic silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Braggio, C. [Dipartimento di Fisica, Universita di Padova, via Marzolo 8, 35131 Padova (Italy); Boscardin, M. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy); Bressi, G. [INFN sez. di Pavia, via Bassi 6, 27100 Pavia (Italy); Carugno, G.; Corti, D. [INFN sez. di Padova, via Marzolo 8, 35131 Padova (Italy); Galeazzi, G. [INFN lab. naz. Legnaro, viale dell' Universita 2, 35020 Legnaro (Italy); Zorzi, N. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy)

    2009-12-15

    We present preliminary measurements for the development of a large volume silicon detector to detect low energy and low rate energy depositions. The tested detector is a one cm-thick silicon PIN diode with an active volume of 31 cm{sup 3}, cooled to the liquid helium temperature to obtain depletion from thermally-generated free carriers. A thorough study has been done to show that effects of charge trapping during drift disappears at a bias field value of the order of 100V/cm.

  6. SNS second target station moderator performance update

    International Nuclear Information System (INIS)

    In its first years of operations of its first target station, the Spallation Neutron Source (SNS) is working towards a facility upgrade by a megawatt-class second target station operated at 20 Hz repetition rate, which is intended to complement the existing ORNL neutron sources, the first SNS target station and the HFIR reactor, with high-intensity cold neutron beams.The first round of optimization calculations converged on larger-volume cylindrical para-hydrogen moderators placed in wing configuration on top and bottom of a flat mercury target, premoderated by layers of ambient water and surrounded by beryllium reflector. The metric of these optimization calculations was time-averaged and energy-integrated neutron brightness below 5 meV with the requirement to be able to serve 20 ports with neutrons. A summary of these calculations will be given including lessons learned from the variety of simulated configurations and detailed neutron performance characteristics like spectral intensities, emission time distributions, local variations of moderator brightness at the viewed areas, and sensitivity of the optimization metric to optimized parameters for the most promising configuration.

  7. Hodgkin's disease: from GTV to CTV, firm data and pending questions; Maladie de hodgkin: du volume tumoral macroscopique au volume-cible anatomoclinique, donnees acquises et problemes non resolus

    Energy Technology Data Exchange (ETDEWEB)

    Lagrange, J.L.; Kirova, Y.; Le Bourgeois, J.P. [Centre Hospitalier Universitaire Henri Mondor, Service de Radiotherapie, 94 - Creteil (France); Cosset, J.M. [Institut Curie, 75 - Paris (France)

    2001-10-01

    The purpose of this article is to specify the target volumes, using ICRU criteria in the treatment of Hodgkin's disease. Because of the complexity of irradiation fields, the literature was carefully reviewed. However, with the variations of the recommendations and in the absence of large-scale studies, usual criteria can still be used. A consensus about the precise specification of the target volumes on CATscan is still urgently awaited. (authors)

  8. Major Targets for 2010

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ This year, the main targets we have set for economic and social development are: increasing GDP by approximately 8 percent, creating jobs for more than 9 million people, keeping the urban registered unemployment rate no higher than 4.6 percent, holding the rise in consumer prices to around 3 percent, and improving the balance of payments.

  9. Target chambers for gammashpere

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Falout, J.W.; Nardi, B.G. [and others

    1995-08-01

    One of our responsibilities for Gammasphere, was designing and constructing two target chambers and associated beamlines to be used with the spectrometer. The first chamber was used with the early implementation phase of Gammasphere, and consisted of two spun-Al hemispheres welded together giving a wall thickness of 0.063 inches and a diameter of 12 inches.

  10. Enhanced target factor analysis.

    Science.gov (United States)

    Rostami, Akram; Abdollahi, Hamid; Maeder, Marcel

    2016-03-10

    Target testing or target factor analysis, TFA, is a well-established soft analysis method. TFA answers the question whether an independent target test vector measured at the same wavelengths as the collection of spectra in a data matrix can be excluded as the spectrum of one of the components in the system under investigation. Essentially, TFA cannot positively prove that a particular test spectrum is the true spectrum of one of the components, it can, only reject a spectrum. However, TFA will not reject, or in other words TFA will accept, many spectra which cannot be component spectra. Enhanced Target Factor Analysis, ETFA addresses the above problem. Compared with traditional TFA, ETFA results in a significantly narrower range of positive results, i.e. the chance of a false positive test result is dramatically reduced. ETFA is based on feasibility testing as described in Refs. [16-19]. The method has been tested and validated with computer generated and real data sets. PMID:26893084

  11. Cancer immunotherapy targeting neoantigens.

    Science.gov (United States)

    Lu, Yong-Chen; Robbins, Paul F

    2016-02-01

    Neoantigens are antigens encoded by tumor-specific mutated genes. Studies in the past few years have suggested a key role for neoantigens in cancer immunotherapy. Here we review the discoveries of neoantigens in the past two decades and the current advances in neoantigen identification. We also discuss the potential benefits and obstacles to the development of effective cancer immunotherapies targeting neoantigens.

  12. ISOLDE back on target

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    Today, Friday 1 August, the ISOLDE installation, supplied by the beams of the PS Booster, restarted its physics programme. After a shutdown of almost a year and a half, there was a real buzz in the air as the first beam of protons hit the target of the first post-LS1 ISOLDE experiment.   One of the new target-handling robots installed by ISOLDE during LS1. Many improvements have been made to the ISOLDE installation during LS1. One of the main projects was the installation of new robots for handling the targets (see photo 1). “Our targets are bombarded by protons from the PS Booster’s beams and become very radioactive,” explains Maria Jose Garcia Borge, spokesperson for the ISOLDE collaboration. “They therefore need to be handled carefully, which is where the robots come in. The robots we had until now were already over 20 years old and were starting to suffer from the effects of radiation. So LS1 was a perfect opportunity to replace them with more moder...

  13. 40 CFR 791.48 - Production volume.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Production volume. 791.48 Section 791... (CONTINUED) DATA REIMBURSEMENT Basis for Proposed Order § 791.48 Production volume. (a) Production volume.... (b) For the purpose of determining fair reimbursement shares, production volume shall include...

  14. The relative volume growth of minimal submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2002-01-01

    The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature.......The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature....

  15. Tumor-Targeted Nanomedicines

    Science.gov (United States)

    ElBayoumi, Tamer A.; Torchilin, Vladimir P.

    2009-01-01

    Purpose The efficacy of drug delivery systems can be enhanced by making them target-specific via the attachment of various ligands. We attempted to enhance tumor accumulation and therapeutic effect of doxorubicin-loaded long-circulating PEGylated liposomes (Doxil®, ALZA Corp.) by coupling to their surface the anti-cancer monoclonal antibody 2C5 (mAb 2C5) with nuclesome (NS)-restricted activity, that can recognize the surface of various tumor but not normal cells and specifically targets pharmaceutical carriers to tumor cells in vitro and in vivo. Following earlier in vitro results with various cancer cell lines, the mAb 2C5-liposomes were studied in vivo vs. plain and non-specific IgG-liposomes. Experimental design Antibody coupling to Doxil® was performed via the “post-insertion” technique. Using 111In-labeled liposomes, the tissue biodistribution and pharmacokinetic profile were studied, as well as their accumulation in tumors in mice was followed by the whole-body γ-scintigraphic imaging. Therapeutic efficacy of mAb 2C5-targeted Doxil® vs. non-specific IgG-modified and original Doxil® controls was followed by registering live tumor growth and determining tumor weights upon mice sacrifice. Results mAb2C5 antibody-targeted liposomes demonstrate enhanced accumulation in tumors, and the in vivo therapeutic activity of the mAb 2C5-Doxil® treatment was found to be significantly superior, resulting in final tumor weights of only 25-40% compared to all Doxil® control treatments, when tested against the subcutaneous primary murine tumors of 4T1 and C26 and human PC3 tumor in nude mice. Conclusions Our results demonstrate the remarkable capability of 2C5-targeted Doxil® to specifically deliver its cargo into various tumors significantly increasing the efficacy of therapy. PMID:19276264

  16. Modern Chemical Technology, Volume 1.

    Science.gov (United States)

    Pecsok, Robert L.; Chapman, Kenneth

    This volume is the first in a series of the ACS "Modern Chemical Technology" (ChemTeC) curriculum which is to prepare chemical technicians. The chapters concentrate on gas chromatography, tests for purity, properties of gases, and gas measurements. Included is the appropriate content, exercises, laboratory activities, and all needed mathematics.…

  17. PATRAM '80. Proceedings. Volume 1

    International Nuclear Information System (INIS)

    Volume 1 contains papers from the following sessions: Plenary Session; Regulations, Licensing and Standards; LMFBR Systems Concepts; Risk/Safety Assessment I; Systems and Package Design; US Institutional Issues; Risk/Safety Assessment II; Leakage, Leak Rate and Seals; Poster Session A; Operations and Systems Experience I; Manufacturing Processes and Materials; and Quality Assurance and Maintenance. Individual papers were processed. (LM)

  18. Moment Maps and Equivariant Volumes

    Institute of Scientific and Technical Information of China (English)

    Alberto DELLA VEDOVA; Roberto PAOLETTI

    2007-01-01

    The study of the volume of big line bundles on a complex projective manifold M has been one of the main veins in the recent interest in the asymptotic properties of linear series. In this article,we consider an equivariant version of this problem, in the presence of a linear action of a reductive group on M.

  19. Summation of IMS Volume Frequencies.

    Science.gov (United States)

    Gordillo, Frank

    A computer program designed to produce summary information on the data processing volume of the Southwest Regional Laboratory's (SWRL) Instructional Management System (IMS) is described. Written in FORTRAN IV for use on an IBM 360 Model 91, the program sorts IMS input data on the basis of run identifier and on the basis of classroom identification…

  20. PATRAM '80. Proceedings. Volume 2

    International Nuclear Information System (INIS)

    Volume 2 contains papers from the following sessions: Safeguards-Related Problems; Neutronics and Criticality; Operations and Systems Experience II; Plutonium Systems; Intermediate Storage in Casks; Operations and Systems Planning; Institutional Issues; Structural and Thermal Evaluation I; Poster Session B; Extended Testing I; Structural and Thermal Evaluation II; Extended Testing II; and Emergency Preparedness and Response. Individual papers were processed. (LM)

  1. Plasma volume in acute hypoxia

    DEFF Research Database (Denmark)

    Poulsen, T D; Klausen, T; Richalet, J P;

    1998-01-01

    Exposure to acute hypoxia is associated with changes in body fluid homeostasis and plasma volume (PV). This study compared a dye dilution technique using Evans' blue (PV[Evans']) with a carbon monoxide (CO) rebreathing method (PV[CO]) for measurements of PV in ten normal subjects at sea level...

  2. Editorial, Volume 5, Issue 1

    Directory of Open Access Journals (Sweden)

    Kristy L. Archuleta

    2014-08-01

    Full Text Available Welcome to Volume 5, Issue 1 of the Journal of Financial Therapy! In this issue, four scholarly papers are presented along with two profiles and a book review. These four papers address very important issues, such as mental health therapists’ competency in working with financial issues, financial stress of college students, parental messages about money, and financial advice media.

  3. History of CERN. Volume 3

    International Nuclear Information System (INIS)

    The present volume continues the story of the history of the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, concentrating on the years between the mid 1960s and the late 1970s. Whereas the first two volumes were the product of a team of historians, this book is rather a collection of studies by authors with very different professional backgrounds and institutional locations. It also differs from the predecessor volumes in the fact that it consists of distinct case studies dealing with a number of issues deemed important. The first part of this volume, containing contributions by historians of science, perceives the laboratory as being at the node of a complex of interconnected relationships between scientists and science managers on the staff, the users in the member states, and the governments which were called upon to finance the laboratory. In part 2 the physical results, obtained at CERN, are surveyed, while in part 3 two chapters are presented, one on engineering and technology, and the other on the research and development of electronic position detectors

  4. Octree-based Volume Sculpting

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas

    1998-01-01

    A volume sculpting system is presented. The system provides tools for interactive editing of a voxel raster that is stored in an octree data structure. Two different modes of sculpting are supported: Sculpting by adding and subtracting solids, and sculpting with tools that are based on a spray ca...... metaphor. The possibility of extending the method to support multiresolution sculpting is discussed....

  5. Eddy current manual, volume 2

    International Nuclear Information System (INIS)

    This report on eddy current testing is divided into three sections: (a) Demonstration of Basic Principles, (b) Practical (Laboratory) Tests and, (c) Typical Certification Questions. It is intended to be used as a supplement to ΣEddy Current Manual, Volume 1Σ (AECL-7523) during CSNDT Foundation Level II and III courses

  6. PATRAM '80. Proceedings. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, H.W. (ed.)

    1980-01-01

    Volume 2 contains papers from the following sessions: Safeguards-Related Problems; Neutronics and Criticality; Operations and Systems Experience II; Plutonium Systems; Intermediate Storage in Casks; Operations and Systems Planning; Institutional Issues; Structural and Thermal Evaluation I; Poster Session B; Extended Testing I; Structural and Thermal Evaluation II; Extended Testing II; and Emergency Preparedness and Response. Individual papers were processed. (LM)

  7. PATRAM '80. Proceedings. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, H.W. (ed.)

    1980-01-01

    Volume 1 contains papers from the following sessions: Plenary Session; Regulations, Licensing and Standards; LMFBR Systems Concepts; Risk/Safety Assessment I; Systems and Package Design; US Institutional Issues; Risk/Safety Assessment II; Leakage, Leak Rate and Seals; Poster Session A; Operations and Systems Experience I; Manufacturing Processes and Materials; and Quality Assurance and Maintenance. Individual papers were processed. (LM)

  8. Modern Chemical Technology, Volume 5.

    Science.gov (United States)

    Pecsok, Robert L., Ed.; Chapman, Kenneth, Ed.

    This volume contains chapters 26-31 for the American Chemical Society (ACS) "Modern Chemical Technology" (ChemTeC) instructional material intended to prepare chemical technologists. Chapter 26 reviews oxidation and reduction, including applications in titrations with potassium permanganate and iodometry. Coordination compounds are described in the…

  9. Watergift klein volume substraat lelie

    NARCIS (Netherlands)

    Kok, B.J.

    2005-01-01

    In eerder onderzoek is gebleken dat het mogelijk is om lelies te broeien op een klein volume substraat. Deze teelt biedt vele mogelijkheden voor een hogere productie per m² en verdere technische ontwikkelingen (o.a. automatisering). Voorwaarde voor een goed teeltresultaat is een goede vochtvoorzieni

  10. The African Experience. Volume I: Syllabus Lectures; Volume II: Bibliographic References; Volume IIIA: Introductory Essays; Volume IIIB: Introductory Essays.

    Science.gov (United States)

    Paden, John N.; Soja, Edward W.

    In response to demands for more and better teaching about Africa in American higher education, the US Office of Education requested that the Program of African Studies at Northwestern University generate a set of teaching materials which could be used in introductory undergraduate courses. Included in these volumes, these materials provide…

  11. Wavelet-Based Volume Visualization

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.; Westenberg, Michel A.

    1999-01-01

    We consider multiresolution visualization of large volume data sets based on wavelets. Starting from a wavelet decomposition of the data, a low resolution image is computed; this approximation can be successively refined. The practical need for such a multiresolution approach is motivated. The mathe

  12. Spectrum '86: Proceedings: Volume 2

    International Nuclear Information System (INIS)

    This document, Volume 2, contains 96 papers on various aspects of radioactive waste management. Session topics include decontamination and decommissioning/endash/industry experience, characterization and safety, techniques, facility and plant decontamination; TRU waste management; regulatory aspects; economics; environmental issues and impacts; construction, operation, and maintenance. Individual papers were processed separately for the data bases

  13. Partial specific volume of xanthan

    Science.gov (United States)

    Wohlfarth, Ch.

    This document is part of Subvolume D2 'Polymer Solutions - Physical Properties and their Relations I (Thermodynamic Properties: PVT -Data and miscellaneous Properties of polymer Solutions) of Volume 6 `Polymers' of Landolt-Börnstein - Group VIII `Advanced Materials and Technologies'.

  14. Maximum-Intensity Volumes for Fast Contouring of Lung Tumors Including Respiratory Motion in 4DCT Planning

    International Nuclear Information System (INIS)

    Purpose: To assess the accuracy of maximum-intensity volumes (MIV) for fast contouring of lung tumors including respiratory motion. Methods and Materials: Four-dimensional computed tomography (4DCT) data of 10 patients were acquired. Maximum-intensity volumes were constructed by assigning the maximum Hounsfield unit in all CT volumes per geometric voxel to a new, synthetic volume. Gross tumor volumes (GTVs) were contoured on all CT volumes, and their union was constructed. The GTV with all its respiratory motion was contoured on the MIV as well. Union GTVs and GTVs including motion were compared visually. Furthermore, planning target volumes (PTVs) were constructed for the union of GTVs and the GTV on MIV. These PTVs were compared by centroid position, volume, geometric extent, and surface distance. Results: Visual comparison of GTVs demonstrated failure of the MIV technique for 5 of 10 patients. For adequate GTVMIVs, differences between PTVs were <1.0 mm in centroid position, 5% in volume, ±5 mm in geometric extent, and ±0.5 ± 2.0 mm in surface distance. These values represent the uncertainties for successful MIV contouring. Conclusion: Maximum-intensity volumes are a good first estimate for target volume definition including respiratory motion. However, it seems mandatory to validate each individual MIV by overlaying it on a movie loop displaying the 4DCT data and editing it for possible inadequate coverage of GTVs on additional 4DCT motion states

  15. Polarization discrimination between repeater false-target and radar target

    Institute of Scientific and Technical Information of China (English)

    SHI LongFei; WANG XueSong; XIAO ShunPing

    2009-01-01

    High fidelity repeater false-target badly affects a radar system's detecting, tracking, and data processing. It is an available approach of confronting false-target for radar that discriminates firstly and then eliminates. Whereas for the technique progress about the repeater false-target jam, it is more and more difficult to discriminate this jam in the time-domain, frequency-domain, or space-domain. The technique using polarization information to discriminate the target and false-target is discussed in this paper. With the difference that false-target signal vector's polarization ratio is fixed and target echo signal vector's polarization ratio is variational along with radar transmission signal's polarization, we transform the discrimination problem to beeline distinguish problem in the 2-dim complex space. The distributing characteristic expression of the false-target discrimination statistic is constructed, with which the discrimination ratio of false-target is analyzed. For the target case, the decomposed model of target scattering matrix and the concept of distinguish quantity are proposed. Then, the discrimination ratio of target can be forecasted according to target distinguish quantity. Thus, the performance of discrimination method has been analyzed integrally. The simulation results demonstrate the method in this paper is effective on the discrimination of target and false-target.

  16. Evolution with Drifting Targets

    CERN Document Server

    Kanade, Varun; Vaughan, Jennifer Wortman

    2010-01-01

    We consider the question of the stability of evolutionary algorithms to gradual changes, or drift, in the target concept. We define an algorithm to be resistant to drift if, for some inverse polynomial drift rate in the target function, it converges to accuracy 1 -- \\epsilon , with polynomial resources, and then stays within that accuracy indefinitely, except with probability \\epsilon , at any one time. We show that every evolution algorithm, in the sense of Valiant (2007; 2009), can be converted using the Correlational Query technique of Feldman (2008), into such a drift resistant algorithm. For certain evolutionary algorithms, such as for Boolean conjunctions, we give bounds on the rates of drift that they can resist. We develop some new evolution algorithms that are resistant to significant drift. In particular, we give an algorithm for evolving linear separators over the spherically symmetric distribution that is resistant to a drift rate of O(\\epsilon /n), and another algorithm over the more general prod...

  17. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    Hill, Amanda Louise; Leinikka Dall, Ole; Andersen, Frits M.

    2014-01-01

    the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...... will need to make efforts to recover all recyclable fractions, and that the increased recycling efforts of only selected municipalities will not be sufficient to reach the target.......Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22...

  18. Physics of polarized targets

    CERN Document Server

    Niinikoski, Tapio

    2014-01-01

    For developing, building and operating solid polarized targets we need to understand several fields of physics that have seen sub stantial advances during the last 50 years. W e shall briefly review a selection of those that are important today. These are: 1) quantum statistical methods to describe saturation and relaxation in magnetic resonance; 2) equal spin temperature model for dy namic nuclear polarization; 3 ) weak saturation during NMR polarization measurement; 4 ) refrigeration using the quantum fluid properties of helium isotopes. These, combined with superconducting magnet technologies, permit today to reach nearly complete pola rization of almost any nuclear spins. Targets can be operated in frozen spin mode in rather low and inhomogeneous field of any orientation, and in DNP mode in beams of high intensity. Beyond such experiments of nuclear and particle physics, applications a re also emerging in macromolecular chemistry and in magnetic resonance imaging. This talk is a tribute to Michel Borghini...

  19. Gene Targeting in Neuroendocrinology.

    Science.gov (United States)

    Candlish, Michael; De Angelis, Roberto; Götz, Viktoria; Boehm, Ulrich

    2015-09-20

    Research in neuroendocrinology faces particular challenges due to the complex interactions between cells in the hypothalamus, in the pituitary gland and in peripheral tissues. Within the hypothalamus alone, attempting to target a specific neuronal cell type can be problematic due to the heterogeneous nature and level of cellular diversity of hypothalamic nuclei. Because of the inherent complexity of the reproductive axis, the use of animal models and in vivo experiments are often a prerequisite in reproductive neuroendocrinology. The advent of targeted genetic modifications, particularly in mice, has opened new avenues of neuroendocrine research. Within this review, we evaluate various mouse models used in reproductive neuroendocrinology and discuss the different approaches to generate genetically modified mice, along with their inherent advantages and disadvantages. We also discuss a variety of versatile genetic tools with a focus on their potential use in reproductive neuroendocrinology.

  20. O*NET Final Technical Report. Volume I [and] Volume II [and] Volume III.

    Science.gov (United States)

    Peterson, Norman G.; Mumford, Michael D.; Borman, Walter C.; Jeanneret, P. Richard; Fleishman, Edwin A.; Levin, Kerry Y.

    This document contains the three volumes of the technical report for development of the prototype of the Occupational Information Network (O*NET), which is intended to replace the "Dictionary of Occupational Titles.""General Introduction" (Norman G. Peterson) presents an overview of O*NET's purpose, content, and structure. "Research Method:…

  1. Targeting fragile X

    OpenAIRE

    Gantois, Ilse; Kooy, R. Frank

    2002-01-01

    Ten years after the identification of the gene responsible for fragile X syndrome, recent studies have revealed a list of mRNAs bound by the fragile X gene product and have identified specific sequences required for the interaction between the fragile X protein and its targets. These results are a breakthrough in understanding why absence of the fragile X protein leads to mental retardation.

  2. Decreased 3D observer variation with matched CT-MRI, for target delineation in nasopharynx cancer

    NARCIS (Netherlands)

    Rasch, C.R.; Steenbakkers, R.J.; Fitton, I.; Duppen, J.C.; Nowak, P.J.; Pameijer, F.A.; Eisbruch, A.; Kaanders, J.H.A.M.; Paulsen, F.; Herk, M. van

    2010-01-01

    PURPOSE: To determine the variation in target delineation of nasopharyngeal carcinoma and the impact of measures to minimize this variation. MATERIALS AND METHODS: For ten nasopharyngeal cancer patients, ten observers each delineated the Clinical Target Volume (CTV) and the CTV elective. After 3D an

  3. Decreased 3D observer variation with matched CT-MRI, for target delineation in Nasopharynx cancer

    NARCIS (Netherlands)

    C.R.N. Rasch (Coen); R.J.H.M. Steenbakkers (Roel); I. Fitton (Isabelle); J.C. Duppen (Joop); P.J.C.M. Nowak (Peter); F.A. Pameijer (Frank); A. Eisbruch (Avraham); J.H.A.M. Kaanders (Johannes); F. Paulsen (Frank); M. Herk (Marcel)

    2010-01-01

    textabstractPurpose: To determine the variation in target delineation of nasopharyngeal carcinoma and the impact of measures to minimize this variation.Materials and methods: For ten nasopharyngeal cancer patients, ten observers each delineated the Clinical Target Volume (CTV) and the CTV elective.

  4. Diffuse volume transport in fluids

    Science.gov (United States)

    Brenner, Howard

    2010-10-01

    The diffuse flux of volume j in a single-component liquid or gas, the subject of this paper, is a purely molecular quantity defined as the difference between the flux of volume n and the convective flux of volume nvˆ carried by the flowing mass, with n the mass flux, vˆ=1/ρ the specific volume, and ρ the mass density. Elementary statistical-mechanical arguments are used to derive the linear constitutive equation j=DS∇lnρ, valid in near-equilibrium fluids from which body forces are absent. Here, DS is the fluid’s self-diffusion coefficient. The present derivation is based on Einstein’s mesoscopic Brownian motion arguments, albeit applied here to volume- rather than particle-transport phenomena. In contrast to these mesoscale arguments, all prior derivations were based upon macroscale linear irreversible thermodynamic (LIT) arguments. DS replaces the thermometric diffusivity α as the phenomenological coefficient appearing in earlier, ad hoc, derivations. The prior scheme based on α, which had been shown to accord with Burnett’s well-known gas-kinetic constitutive data for the heat flux and viscous stress, carries over intact to now show comparable accord of DS with these same data, since for gases the dimensionless Lewis number Le=α/DS is essentially unity. On the other hand for most liquids, where Le≫1, use of DS in place of α is shown to agree much better with existing experimental data for liquids. For the case of binary mixtures it is shown for the special case of isothermal, isobaric, force-free, Fick’s law-type molecular diffusion processes that j=D∇lnρ, where D is the binary diffusion coefficient. In contrast with the preceding use in the single-component case of both mesoscopic and LIT models to obtain a constitutive equation for j, the corresponding mixture result is derived here without use of any physical model whatsoever. Rather, the derivation effectively requires little more than the respective definitions of the diffuse volume

  5. Large-volume en-bloc staining for electron microscopy-based connectomics

    OpenAIRE

    Hua, Yunfeng; Laserstein, Philip; Helmstaedter, Moritz

    2015-01-01

    Large-scale connectomics requires dense staining of neuronal tissue blocks for electron microscopy (EM). Here we report a large-volume dense en-bloc EM staining protocol that overcomes the staining gradients, which so far substantially limited the reconstructable volumes in three-dimensional (3D) EM. Our protocol provides densely reconstructable tissue blocks from mouse neocortex sized at least 1 mm in diameter. By relaxing the constraints on precise topographic sample targeting, it makes the...

  6. Inflation targeting and core inflation

    OpenAIRE

    Julie Smith

    2005-01-01

    This paper examines the interaction of core inflation and inflation targeting as a monetary policy regime. Interest in core inflation has grown because of inflation targeting. Core inflation is defined in numerous ways giving rise to many potential measures; this paper defines core inflation as the best forecaster of inflation. A cross-country study finds before the start of inflation targeting, but not after, core inflation differs between non-inflation targeters and inflation targeters. Thr...

  7. Waste minimization handbook, Volume 1

    International Nuclear Information System (INIS)

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility's life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996

  8. Waste minimization handbook, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility`s life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996.

  9. Seismic engineering: 1993--Volume 1

    International Nuclear Information System (INIS)

    Separate abstracts were prepared for the technical papers presented at the American Society of Mechanical Engineers 1993 Pressure Vessels and Piping Conference on July 25--29 in Denver, Colorado. Knowledge gained from seismic effect and method development for seismic analysis have seen continuing advancement in the past year. This volume contains fifteen papers dealing with seismic methods, analysis, and applications, nine papers dealing with piping seismic design and evaluation, and eight papers dealing with piping supports and components

  10. Prices Up and Volumes Stable

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011 First Half China Garment Industry Report Exports Grew at a Slower Pace China Customs reported the garment & accessories export value of $51.286 billion for the first five months of this year, up 23.12% y/y, accounting for 56.28 percent of the total, 5% lower than the previous year’s points.Despite sales prices increase, sales volume remain stable. From Jan. to May

  11. Analytic torsion and symplectic volume

    DEFF Research Database (Denmark)

    McLellan, Brendan Donald Kenneth

    2013-01-01

    This article studies the abelian analytic torsion on a closed, oriented, quasi-regular Sasakian three-manifold and identifies this quantity as a specific multiple of the natural unit symplectic volume form on the moduli space of flat abelian connections. This identification effectively computes...... the analytic torsion explicitly in terms of Seifert data for a given quasi-regular Sasakian structure on a three-manifold....

  12. Memorial volume for Y. Nambu

    CERN Document Server

    Chang, Lay Nam; Han, Moo-Young; Phua, Kok Khoo

    2016-01-01

    We have lost one of the giants of the twentieth century physics when Yoichiro Nambu passed away in July, 2015, at the age of 94. Today's Standard Model, though still incomplete in many respects, is the culmination of the most successful theory of the Universe to date, and it is built upon foundations provided by discoveries made by Nambu in the 1960s: the mechanism of spontaneously broken symmetry in Nature (with G Jona-Lasinio) and the hidden new SU(3) symmetry of quarks and gluons (with M-Y Han). In this volume honoring Nambu's memory, World Scientific Publishing presents a unique collection of papers written by his former colleagues, collaborating researchers and former students and associates, not only citing Nambu's great contributions in physics but also many personal and private reminiscences, some never told before. This volume also contains the very last scientific writing by Professor Nambu himself, discussing the development of particle physics. This book is a volume for all who benefited not on...

  13. Volumetric Spectroscopic Imaging of Glioblastoma Multiforme Radiation Treatment Volumes

    Energy Technology Data Exchange (ETDEWEB)

    Parra, N. Andres [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Maudsley, Andrew A. [Department of Radiology, University of Miami Miller School of Medicine, Miami, Florida (United States); Gupta, Rakesh K. [Department of Radiology and Imaging, Fortis Memorial Research Institute, Gurgaon, Haryana (India); Ishkanian, Fazilat; Huang, Kris [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Walker, Gail R. [Biostatistics and Bioinformatics Core Resource, Sylvester Cancer Center, University of Miami Miller School of Medicine, Miami, Florida (United States); Padgett, Kyle [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Department of Radiology, University of Miami Miller School of Medicine, Miami, Florida (United States); Roy, Bhaswati [Department of Radiology and Imaging, Fortis Memorial Research Institute, Gurgaon, Haryana (India); Panoff, Joseph; Markoe, Arnold [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Stoyanova, Radka, E-mail: RStoyanova@med.miami.edu [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States)

    2014-10-01

    Purpose: Magnetic resonance (MR) imaging and computed tomography (CT) are used almost exclusively in radiation therapy planning of glioblastoma multiforme (GBM), despite their well-recognized limitations. MR spectroscopic imaging (MRSI) can identify biochemical patterns associated with normal brain and tumor, predominantly by observation of choline (Cho) and N-acetylaspartate (NAA) distributions. In this study, volumetric 3-dimensional MRSI was used to map these compounds over a wide region of the brain and to evaluate metabolite-defined treatment targets (metabolic tumor volumes [MTV]). Methods and Materials: Volumetric MRSI with effective voxel size of ∼1.0 mL and standard clinical MR images were obtained from 19 GBM patients. Gross tumor volumes and edema were manually outlined, and clinical target volumes (CTVs) receiving 46 and 60 Gy were defined (CTV{sub 46} and CTV{sub 60}, respectively). MTV{sub Cho} and MTV{sub NAA} were constructed based on volumes with high Cho and low NAA relative to values estimated from normal-appearing tissue. Results: The MRSI coverage of the brain was between 70% and 76%. The MTV{sub NAA} were almost entirely contained within the edema, and the correlation between the 2 volumes was significant (r=0.68, P=.001). In contrast, a considerable fraction of MTV{sub Cho} was outside of the edema (median, 33%) and for some patients it was also outside of the CTV{sub 46} and CTV{sub 60}. These untreated volumes were greater than 10% for 7 patients (37%) in the study, and on average more than one-third (34.3%) of the MTV{sub Cho} for these patients were outside of CTV{sub 60}. Conclusions: This study demonstrates the potential usefulness of whole-brain MRSI for radiation therapy planning of GBM and revealed that areas of metabolically active tumor are not covered by standard RT volumes. The described integration of MTV into the RT system will pave the way to future clinical trials investigating outcomes in patients treated based on

  14. Cell volume regulation: physiology and pathophysiology

    DEFF Research Database (Denmark)

    Lambert, I H; Hoffmann, E K; Pedersen, Stine Helene Falsig

    2008-01-01

    Cell volume perturbation initiates a wide array of intracellular signalling cascades, leading to protective and adaptive events and, in most cases, activation of volume-regulatory osmolyte transport, water loss, and hence restoration of cell volume and cellular function. Cell volume is challenged....../hypernatremia. On the other hand, it has recently become clear that an increase or reduction in cell volume can also serve as a specific signal in the regulation of physiological processes such as transepithelial transport, cell migration, proliferation and death. Although the mechanisms by which cell volume perturbations...

  15. Computing proton dose to irregularly moving targets

    Science.gov (United States)

    Phillips, Justin; Gueorguiev, Gueorgui; Shackleford, James A.; Grassberger, Clemens; Dowdell, Stephen; Paganetti, Harald; Sharp, Gregory C.

    2014-08-01

    Purpose: While four-dimensional computed tomography (4DCT) and deformable registration can be used to assess the dose delivered to regularly moving targets, there are few methods available for irregularly moving targets. 4DCT captures an idealized waveform, but human respiration during treatment is characterized by gradual baseline shifts and other deviations from a periodic signal. This paper describes a method for computing the dose delivered to irregularly moving targets based on 1D or 3D waveforms captured at the time of delivery. Methods: The procedure uses CT or 4DCT images for dose calculation, and 1D or 3D respiratory waveforms of the target position at time of delivery. Dose volumes are converted from their Cartesian geometry into a beam-specific radiological depth space, parameterized in 2D by the beam aperture, and longitudinally by the radiological depth. In this new frame of reference, the proton doses are translated according to the motion found in the 1D or 3D trajectory. These translated dose volumes are weighted and summed, then transformed back into Cartesian space, yielding an estimate of the dose that includes the effect of the measured breathing motion. The method was validated using a synthetic lung phantom and a single representative patient CT. Simulated 4DCT was generated for the phantom with 2 cm peak-to-peak motion. Results: A passively-scattered proton treatment plan was generated using 6 mm and 5 mm smearing for the phantom and patient plans, respectively. The method was tested without motion, and with two simulated breathing signals: a 2 cm amplitude sinusoid, and a 2 cm amplitude sinusoid with 3 cm linear drift in the phantom. The tumor positions were equally weighted for the patient calculation. Motion-corrected dose was computed based on the mid-ventilation CT image in the phantom and the peak exhale position in the patient. Gamma evaluation was 97.8% without motion, 95.7% for 2 cm sinusoidal motion, 95.7% with 3 cm drift in the

  16. Upper extremity muscle volumes and functional strength after resistance training in older adults.

    Science.gov (United States)

    Daly, Melissa; Vidt, Meghan E; Eggebeen, Joel D; Simpson, W Greg; Miller, Michael E; Marsh, Anthony P; Saul, Katherine R

    2013-04-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions. PMID:22952203

  17. Targeted therapy for sarcomas

    Directory of Open Access Journals (Sweden)

    Forscher C

    2014-03-01

    Full Text Available Charles Forscher,1 Monica Mita,2 Robert Figlin3 1Sarcoma Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA; 2Experimental Therapeutics Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA; 3Academic Development Program, Samuel Oschin Comprehensive Cancer Institute, and Division of Hematology/Oncology, Cedars-Sinai Medical Center, Los Angeles, CA, USA Abstract: Sarcomas are tumors of mesenchymal origin that make up approximately 1% of human cancers. They may arise as primary tumors in either bone or soft tissue, with approximately 11,280 soft tissue tumors and 2,650 bone tumors diagnosed each year in the United States. There are at least 50 different subtypes of soft tissue sarcoma, with new ones described with ever-increasing frequency. One way to look at sarcomas is to divide them into categories on the basis of their genetic make-up. One group of sarcomas has an identifiable, relatively simple genetic signature, such as the X:18 translocation seen in synovial sarcoma or the 11:22 translocation seen in Ewing's sarcoma. These specific abnormalities often lead to the presence of fusion proteins, such as EWS-FLI1 in Ewing's sarcoma, which are helpful as diagnostic tools and may become therapeutic targets in the future. Another group of sarcomas is characterized by complex genetic abnormalities as seen in leiomyosarcoma, osteosarcoma, and undifferentiated sarcoma. It is important to keep these distinctions in mind when contemplating the development of targeted agents for sarcomas. Different abnormalities in sarcoma could be divided by tumor subtype or by the molecular or pathway abnormality. However, some existing drugs or drugs in development may interfere with or alter more than one of the presented pathways. Keywords: sarcoma, targeted agents, tyrosine kinase inhibitors, mTor inhibition

  18. Cooperative assembly in targeted drug delivery

    Science.gov (United States)

    Auguste, Debra

    2012-02-01

    Described as cell analogues, liposomes are self-assembled lipid bilayer spheres that encapsulate aqueous volumes. Liposomes offer several drug delivery advantages due to their structural versatility related to size, composition, bilayer fluidity, and ability to encapsulate a large variety of compounds non-covalently. However, liposomes lack the structural information embedded within cell membranes. Partitioning of unsaturated and saturated lipids into liquid crystalline (Lα) and gel phase (Lβ) domains, respectively, affects local molecular diffusion and elasticity. Liposome microdomains may be used to pattern molecules, such as antibodies, on the liposome surface to create concentrated, segregated binding regions. We have synthesized, characterized, and evaluated a series of homogeneous and heterogeneous liposomal vehicles that target inflamed endothelium. These drug delivery vehicles are designed to complement the heterogeneous presentation of lipids and receptors on endothelial cells (ECs). EC surfaces are dynamic; they segregate receptors within saturated lipid microdomains on the cell surface to regulate binding and signaling events. We have demonstrated that cooperative binding of two antibodies enhances targeting by multiple fold. Further, we have shown that organization of these antibodies on the surface can further enhance cell uptake. The data suggest that EC targeting may be enhanced by designing liposomes that mirror the segregated structure of lipid and receptor molecules involved in neutrophil-EC adhesion. This strategy is employed in an atherosclerotic mouse model in vivo.

  19. High efficiency diffusion molecular retention tumor targeting.

    Directory of Open Access Journals (Sweden)

    Yanyan Guo

    Full Text Available Here we introduce diffusion molecular retention (DMR tumor targeting, a technique that employs PEG-fluorochrome shielded probes that, after a peritumoral (PT injection, undergo slow vascular uptake and extensive interstitial diffusion, with tumor retention only through integrin molecular recognition. To demonstrate DMR, RGD (integrin binding and RAD (control probes were synthesized bearing DOTA (for (111 In(3+, a NIR fluorochrome, and 5 kDa PEG that endows probes with a protein-like volume of 25 kDa and decreases non-specific interactions. With a GFP-BT-20 breast carcinoma model, tumor targeting by the DMR or i.v. methods was assessed by surface fluorescence, biodistribution of [(111In] RGD and [(111In] RAD probes, and whole animal SPECT. After a PT injection, both probes rapidly diffused through the normal and tumor interstitium, with retention of the RGD probe due to integrin interactions. With PT injection and the [(111In] RGD probe, SPECT indicated a highly tumor specific uptake at 24 h post injection, with 352%ID/g tumor obtained by DMR (vs 4.14%ID/g by i.v.. The high efficiency molecular targeting of DMR employed low probe doses (e.g. 25 ng as RGD peptide, which minimizes toxicity risks and facilitates clinical translation. DMR applications include the delivery of fluorochromes for intraoperative tumor margin delineation, the delivery of radioisotopes (e.g. toxic, short range alpha emitters for radiotherapy, or the delivery of photosensitizers to tumors accessible to light.

  20. International Linear Collider Technical Design Report (Volumes 1 through 4)

    Energy Technology Data Exchange (ETDEWEB)

    Harrison M.

    2013-03-27

    The design report consists of four volumes: Volume 1, Executive Summary; Volume 2, Physics; Volume 3, Accelerator (Part I, R and D in the Technical Design Phase, and Part II, Baseline Design); and Volume 4, Detectors.

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

    International Nuclear Information System (INIS)

    In a consecutive series of 10 patients with primary irradiated endometrial carcinoma we analyzed the correlation between target volume and treated volume using either standard 1-channel applicators or individual Heyman-applicators. Application of the ovoids was followed by a planning CT scan for all patients. Based on this, target volume (uterus volume) was estimated on a 3D-planning system. According to the measurable length of the uterus cavity we determined the corresponding standard 1-channel applicator and calculated the respectively treated volume. Estimating the advantages of an optimized treatment planning strategy for individual Heyman-applications we compared the treated volumes, which result from a standardized and optimized treatment planning procedure. The mean uterus volume was 180 cm3 (range 57 to 316 cm3). Asymmetric uterus configurations with longitudinal or sagittal side differences exceeding 1 cm were found in 40% of the cases. Using standard 1-channel applicators on average 47% (range 25 to 89%) of the uterus volume were enclosed by the treated volume compared to 70% for Heyman-applications. Differentiating these individual applications according to the variable treatment modality values of mean 66% (range 36 to 110%) for the standardized and 73% (range 48 to 95%) for the optimized treatment planning strategy were found. Moreover optimized planning modalities led to an improved coverage of the target volume in 5 out of 10 cases with an increase in volume of 20% on average (range 11 to 32%). In 3 cases changes of less than 5% were noticed (no improvement). In order to protect organs at risk treated volume had to be decreased in 2 cases for 19% and 40% respectively. (orig./MG)

  2. Site Environmental Report for 2005 Volume I and Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Ruggieri, Michael

    2006-07-07

    Each year, Ernest Orlando Lawrence Berkeley National Laboratory prepares an integrated report on its environmental programs to satisfy the requirements of United States Department of Energy Order 231.1A, ''Environment, Safety, and Health Reporting''. The ''Site Environmental Report for 2005'' summarizes Berkeley Lab's environmental management performance, presents environmental monitoring results, and describes significant programs for calendar year 2005. (Throughout this report, Ernest Orlando Lawrence Berkeley National Laboratory is referred to as ''Berkeley Lab'', ''the Laboratory'', ''Lawrence Berkeley National Laboratory'', and ''LBNL''.) The report is separated into two volumes. Volume I contains an overview of the Laboratory, the status of environmental programs, and summarized results from surveillance and monitoring activities. This year's Volume I text body is organized into an executive summary followed by six chapters. The report's structure has been reorganized this year, and it now includes a chapter devoted to environmental management system topics. Volume II contains individual data results from surveillance and monitoring activities. The ''Site Environmental Report'' is distributed by releasing it on the Web from the Berkeley Lab Environmental Services Group (ESG) home page, which is located at http://www.lbl.gov/ehs/esg/. Many of the documents cited in this report also are accessible from the ESG Web page. CD and printed copies of this Site Environmental Report are available upon request. The report follows the Laboratory's policy of using the International System of Units (SI), also known as the metric system of measurements. Whenever possible, results are also reported using the more conventional (non-SI) system of measurements, because the non-SI system is referenced by several current

  3. Low intensity beam target unit

    CERN Multimedia

    1976-01-01

    This is a wheel fitted with many targets around its periphery (each with three longitudinally arranged thin rods) of which one is placed into the beam via a rotation of the wheel. Upstream of each target is placed a luminescent screen, aligbed on each target axis and viewed with a TV camera, to make sure that one is hitting the target. This target unit was probably used to study target's behaviour (like beam heating). Gualtiero Del Torre stands on the left, Pierre Gerdil on the right.

  4. System for manipulating and optically targeting micro objects

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to a system 100 for independently holding and manipulating one or more microscopic objects 158 and for targeting at least a part of the one or more microscopic objects within a trapping volume 102 with electromagnetic radiation 138. The system comprises trapping means...... for holding and manipulating the one or more microscopic objects and electromagnetic radiation targeting means (116). The light means comprising a light source and a spatial light modulator which serve to modify the light from the light source so as to enable specific illumination of at least a part...... of the one or more microscopic objects. The trapping means and the electromagnetic radiation targeting means (116) are enabled to function independently of each other, so that the trapped objects may be moved around without taking being dependent on which parts are being targeted and vice versa....

  5. Shielding calculations for a production target for secondary beams

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K.E.; Back, B.B.; Jiang, C.L. [and others

    1995-08-01

    In order to estimate the amount of shielding required for a radioactive beam facility dose rate were performed. The calculations for production targets with different geometries were performed. The calculations were performed with the MSU shielding code assuming a 500-p{mu}A 200-MeV deuteron beam stopped in a thick Al target. The target and the ion-optical elements for beam extraction are located in a 2 m{sup 3} large volume at the center of the production cell. These dose rate calculations show that with a combination of Fe and concrete it is possible to reduce the dose rate expected at the surface of a 7-m-wide cube housing the production target to less than 2 mrem/hr.

  6. LLE Review: Volume 63. Quarterly report, April--June 1995

    International Nuclear Information System (INIS)

    This volume of the LLE Review, covering the period of April--June 1995, includes a description of the initial performance results of the upgraded OMEGA laser system. A series of acceptance tests were completed, demonstrating that all 60 beams can irradiate targets with more energy and better beam balance than was required by the Department of Energy's acceptance criteria. Other articles in this volume include a description of a novel energy measurement system used to diagnose all 60 OMEGA beams; a theoretical calculation of the cutoff wave number of the ablative Rayleigh-Taylor instability, applicable to both direct and indirect drive; a description of a new algorithm used for designing distributed phase plates that will produce super-Gaussian focal-plane irradiance profiles: a study of the photoresponse of high-Tc YBCO thin films; and a description of magnetorheological finishing, a new process for optics polishing

  7. Powder metallurgical high performance materials. Proceedings. Volume 4: late papers

    International Nuclear Information System (INIS)

    This is the fourth volume (late papers) of the 15th International Plansee seminar 2001 which general theme was 'Powder metallurgical high performance materials'. The seminar looked beyond the refractory metals and cemented carbides, which remain as its focus, to novel classes of materials, such as intermetallic compounds, with potential for high temperature applications. This volume 4 contains papers dealing with high performance P/M metals (ITER and fusion reactors, solid targets, materials microstructure, novel alloys, etc.), P/M hard materials ( production and characterization, tungsten carbides, titanium carbides, microstructural design, coatings composition and performance, etc.) and general topics. From 37 papers 24 correspond to INIS subject scope and they were indexed separately. (nevyjel)

  8. Target Housing Material Options

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-11

    With gas cooling, heat transfer coefficients are low compared to water. The benefit of gas from a heat transfer point of view is that there is really no upper temperature limit for the coolant, as compared to water, which is limited ultimately by the critical point, and in practice the critical heat flux. In our case with parallel flow channels, water is limited to even lower operating limits by nucleate boiling. So gas can get as hot as the containment material will allow, but to get the density and heat transfer up to something reasonable, we must also increase pressure, thus increasing stress on the containment, namely the front and back faces. We are designing to ASME BPVC, which, for most materials allows a maximum stress of UTS/3. So we want the highest possible UTS. For reference, the front face stress in the 12 mm target at 300 psi was about 90 MPa. The inconel 718 allowable stress at 900°C is 1/3 of 517 or 172 MPa. So we are in a very safe place, but the uTS is dropping rapidly with temperature above 900°C. As we increase target diameter, the challenge will be to keep the stress down. We are probably looking at keeping the allowable at or above the present value, and at as high a temperature as possible.

  9. RADTRAN 4: User guide. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Neuhauser, K S [Sandia National Labs., Albuquerque, NM (United States); Kanipe, F L [GRAM, Inc., Albuquerque, NM (United States)

    1992-01-01

    RADTRAN 4 is used to evaluate radiological consequences of incident-free transportation, as well as the radiological risks from vehicular accidents occurring during transportation. This User Guide is Volume 3 in a series of four volume of the documentation of the RADTRAN 4 computer code for transportation risk analysis. The other three volumes are Volume 1, the Executive Summary; Volume 2, the Technical Manual; and Volume 4, the Programmer`s Manual. The theoretical and calculational basis for the operations performed by RADTRAN 4 are discussed in Volume 2. Throughout this User Guide the reader will be referred to Volume 2 for detailed discussions of certain RADTRAN features. This User Guide supersedes the document ``RADTRAN III`` by Madsen et al. (1983). This RADTRAN 4 User Guide specifies and describes the required data, control inputs, input sequences, user options, program limitations, and other activities necessary for execution of the RADTRAN 4 computer code.

  10. Crater morphology in sandstone targets: The MEMIN impact parameter study

    Science.gov (United States)

    Dufresne, Anja; Poelchau, Michael H.; Kenkmann, Thomas; Deutsch, Alex; Hoerth, Tobias; SchńFer, Frank; Thoma, Klaus

    2013-01-01

    Hypervelocity (2.5-7.8 km s-1) impact experiments into sandstone were carried out to investigate the influence of projectile velocity and mass, target pore space saturation, target-projectile density contrast, and target layer orientation on crater size and shape. Crater size increases with increasing projectile velocity and mass as well as with increasing target pore space saturation. Craters in water-saturated porous targets are generally shallower and larger in volume and in diameter than craters from equivalent impacts into dry porous sandstone. Morphometric analyses of the resultant craters, 5-40 cm in diameter, reveal features that are characteristic of all of our experimental craters regardless of impact conditions (I) a large central depression within a fragile, light-colored central part, and (II) an outer spallation zone with areas of incipient spallation. Two different mechanical processes, grain fragmentation and intergranular tensile fracturing, are recorded within these crater morphologies. Zone (I) approximates the shape of the transient crater formed by material compression, displacement, comminution, and excavation flow, whereas (II) is the result of intergranular tensile fracturing and spallation. The transient crater dimensions are reconstructed by fitting quadric parabolas to crater profiles from digital elevation models. The dimensions of this transient and of the final crater show the same trends: both increase in volume with increasing impact energy, and with increasing water saturation of the target pore space. The relative size of the transient crater (in percent of the final crater volume) decreases with increasing projectile mass and velocity, signifying a greater contribution of spallation on the final crater size when projectile mass and velocity are increased.

  11. GTV and CTV in radiation therapy of tumours of the oral cavity; Volume tumoral macroscopique et volume-cible anatomoclinique en radiotherapie. Tumeur de la cavite buccale

    Energy Technology Data Exchange (ETDEWEB)

    Bardet, E. [Centre Regional de Lutte Contre le Cancer Rene-Gauducheau, Service de Radiotherapie, 44 - Nantes (France); Piot, B.; Savary, V. [Centre Hospitalier Universitaire de Nantes, Service de Stomatologie, 44 - Nantes (France); Gayet, M. [Centre Hospitalier Universitaire de Nantes, Service de Radiologie, 44 - Nantes (France)

    2001-10-01

    Radiation therapy, either alone or combined with surgery is a cornerstone in the treatment of oral cavity tumors. Target volumes to be treated with external beam radiation must take under consideration the initial tumor location, providing information on satellites lymph nodes to be irradiated as well. Modern imaging, with emphasis on CT scan with injection, is now mandatory for a better analysis of initial lesions including both tumor location and invaded lymph nodes. Tumor volumes based on clinical examination and CT scan analysis might be divided in two groups. First, volumes susceptible to receive a prophylactic irradiation for an hypothetical microscopic spread (CTV) to be treated with a prophylactic dose; second, volumes including lesions visible clinically or on CT scan that should receive a higher radiation dose (GTV). Clinical tolerance will largely be depending upon radiation-induced mucositis, impairing food intake. Radiation techniques aiming at normal tissues preservation should be used, including devices allowing keeping an open mouth during radiation delivery. (authors)

  12. Oncoplastic breast conserving surgery: Volume replacement vs. volume displacement.

    Science.gov (United States)

    Noguchi, M; Yokoi-Noguchi, M; Ohno, Y; Morioka, E; Nakano, Y; Kosaka, T; Kurita, T

    2016-07-01

    Oncoplastic breast conserving surgery (BCS) has emerged as a third option between conventional BCS and mastectomy. Oncoplastic BCS includes two fundamentally different approaches: volume replacement and volume displacement. The former involves partial mastectomy and immediate reconstruction of the breast with the transposition of autologous tissue from elsewhere, while the latter involves partial mastectomy and using the remaining breast tissue to fill the defect resulting from extirpation of the tumor. There are several benefits associated with oncoplastic BCS. First, it allows partial mastectomy without cosmetic penalties, and can achieve better cosmetic outcomes than total mastectomy with immediate breast reconstruction. Second, it avoids the need for total mastectomy in an increasing number of patients without compromising local control. Third, partial breast reconstruction is less extensive and has fewer complications than conventional procedures. Partial mastectomy and partial breast reconstruction can be carried out either simultaneously as a one-stage procedure, or using a two-stage approach. Although patients prefer a one-stage procedure, it requires intraoperative confirmation of complete tumor excision using frozen-section analysis. Moreover, oncoplastic BCS requires combined skills, knowledge, and understanding of both oncological and plastic surgeries, which may be optimally achieved by an oncoplastic surgeon. PMID:26988623

  13. Functional renormalisation group in a finite volume

    OpenAIRE

    Fister, Leonard; Pawlowski, Jan Martin

    2015-01-01

    We study a $\\phi^4$-theory at finite temperature in a finite volume. Quantum, thermal and volume fluctuations are treated with the functional renormalisation group. Specifically, we focus on the interplay of temperature and length scales driving the system. We find that thermodynamical observables at finite volume such as the pressure approach the infinite volume limit similarly to that of the vanishing temperature limit. We also advance the functional renormalisation group method at finite v...

  14. Finite volume hydromechanical simulation in porous media

    OpenAIRE

    Nordbotten, Jan Martin

    2014-01-01

    Cell-centered finite volume methods are prevailing in numerical simulation of flow in porous media. However, due to the lack of cell-centered finite volume methods for mechanics, coupled flow and deformation is usually treated either by coupled finite-volume-finite element discretizations, or within a finite element setting. The former approach is unfavorable as it introduces two separate grid structures, while the latter approach loses the advantages of finite volume methods for the flow equ...

  15. Computational stress analysis using finite volume methods

    OpenAIRE

    Fallah, Nosrat Allah

    2000-01-01

    There is a growing interest in applying finite volume methods to model solid mechanics problems and multi-physics phenomena. During the last ten years an increasing amount of activity has taken place in this area. Unlike the finite element formulation, which generally involves volume integrals, the finite volume formulation transfers volume integrals to surface integrals using the divergence theorem. This transformation for convection and diffusion terms in the governing equations, ensures...

  16. The parallel volume at large distances

    DEFF Research Database (Denmark)

    Kampf, Jürgen

    In this paper we examine the asymptotic behavior of the parallel volume of planar non-convex bodies as the distance tends to infinity. We show that the difference between the parallel volume of the convex hull of a body and the parallel volume of the body itself tends to . This yields a new proof...... for the fact that a planar body can only have polynomial parallel volume, if it is convex. Extensions to Minkowski spaces and random sets are also discussed....

  17. The parallel volume at large distances

    DEFF Research Database (Denmark)

    Kampf, Jürgen

    In this paper we examine the asymptotic behavior of the parallel volume of planar non-convex bodies as the distance tends to infinity. We show that the difference between the parallel volume of the convex hull of a body and the parallel volume of the body itself tends to 0. This yields a new proof...... for the fact that a planar body can only have polynomial parallel volume, if it is convex. Extensions to Minkowski spaces and random sets are also discussed....

  18. On the volume of cremated remains

    DEFF Research Database (Denmark)

    Harvig, Lise Lock; Lynnerup, Niels

    2013-01-01

    Harvig, L., Lynnerup, N. 2013. On the effective volume of prehistoric cremains - a comparative study of cremated bone volume measured manually and assessed by Computed Tomography. Journal of Archaeological Science 40, p. 2713–2722.......Harvig, L., Lynnerup, N. 2013. On the effective volume of prehistoric cremains - a comparative study of cremated bone volume measured manually and assessed by Computed Tomography. Journal of Archaeological Science 40, p. 2713–2722....

  19. Optimizing Reactors Selection and Sequencing:Minimum Cost versus Minimum Volume

    Institute of Scientific and Technical Information of China (English)

    Rachid Chebbi

    2014-01-01

    The present investigation targets minimum cost of reactors in series for the case of one single chemical reaction, considering plug flow and stirred tank reactor(s) in the sequence of flow reactors. Using Guthrie’s cost correlations three typical cases were considered based on the profile of the reaction rate reciprocal versus conversion. Significant differences were found compared to the classical approach targeting minimum total reactor volume.

  20. Environmental Report 1995. Volume 1

    International Nuclear Information System (INIS)

    This report contains the results of Lawrence Livermore National Laboratory's (LLNL) environmental monitoring and compliance effort and an assessment of the impact of LLNL operations on the environment and the public. This first volume describes LLNL's environmental impact and compliance activities and features descriptive and explanatory text, summary data tables, and plots showing data trends. The summary data include measures of the center of data, their spread or variability, and their extreme values. Chapters on monitoring air, sewage, surface water, ground water, soil and sediment, vegetation and foodstuff, and environmental radiation are present

  1. Environmental Report 1995. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Harrach, R.J.; Failor, R.A.; Gallegos, G.M. [and others

    1996-09-01

    This report contains the results of Lawrence Livermore National Laboratory`s (LLNL) environmental monitoring and compliance effort and an assessment of the impact of LLNL operations on the environment and the public. This first volume describes LLNL`s environmental impact and compliance activities and features descriptive and explanatory text, summary data tables, and plots showing data trends. The summary data include measures of the center of data, their spread or variability, and their extreme values. Chapters on monitoring air, sewage, surface water, ground water, soil and sediment, vegetation and foodstuff, and environmental radiation are present.

  2. Spectrum '86: Proceedings: Volume 1

    International Nuclear Information System (INIS)

    This document, Volume 1 of two, contains 100 papers on various aspects of Radioactive Waste Management. Session topics include: nuclear success stories; low-level waste-grout; filtration and ion exchange, qualification, and pretreatment; solid waste treatment/endash/special grouts, and incineration; equipment design/endash/remote technology, and special equipment; high-level waste/endash/international vitrification projects, plans and system testing, product performance, meltor and product testing, off-gas behavior and processing. Individual reports were processed separately for the data bases

  3. Comparing Volumes of Prisms and Pyramids

    Science.gov (United States)

    Vinogradova, Natalya

    2012-01-01

    Students' experience in using formulas for volumes is often limited to substituting numbers into given formulas. An activity presented in this article may help students make connections between the formulas for volumes of prisms and volumes of pyramids. In addition, some interesting facts from number theory arise, demonstrating strong connections…

  4. Culture of Schools. Final Report. Volume IV.

    Science.gov (United States)

    American Anthropological Association, Washington, DC.

    The final volume of this 4-volume report contains further selections from "Anthropological Perspectives on Education," a monograph to be published by Basic Books of New York. (Other selections are in Vol. III, SP 003 902.) Monograph selections appearing in this volume are: "Great Tradition, Little Tradition, and Formal Education;""Indians,…

  5. A Note on Inflation Targeting.

    Science.gov (United States)

    Lai, Ching-chong; Chang, Juin-jen

    2001-01-01

    Presents a pedagogical graphical exposition to illustrate the stabilizing effect of price target zones. Finds that authorities' commitment to defend a price target zone affects the public's inflation expectations and, in turn, reduces actual inflation. (RLH)

  6. Some Issues in Inflation Targeting

    OpenAIRE

    Andrew Haldane

    1997-01-01

    This paper discusses some of the operational issues relevant to the implementation of an inflation-targeting regime. In particular it focuses on: whether inflation targeting is 'new'; whether (and how) the forward-looking nature of inflation-targeting helps to prevent instabilities in inflation; whether inflation-targeting potentially destabilises output; and whether it requires too much knowledge on the part of the authorities. The paper argues that none of these propositions is in general c...

  7. ORION laser target diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, C. D.; Edwards, R. D.; Andrew, J. E.; James, S. F.; Gardner, M. D.; Comley, A. J.; Vaughan, K.; Horsfield, C. J.; Rubery, M. S.; Rothman, S. D.; Daykin, S.; Masoero, S. J.; Palmer, J. B.; Meadowcroft, A. L.; Williams, B. M.; Gumbrell, E. T.; Fyrth, J. D.; Brown, C. R. D.; Hill, M. P.; Oades, K. [Plasma Physics Department, Atomic Weapons Establishment, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom); and others

    2012-10-15

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  8. Electromagnetic targeting of guns

    Energy Technology Data Exchange (ETDEWEB)

    Pogue, E.W.; Boat, R.M.; Holden, D.N.; Lopez, J.R. [and others

    1996-10-01

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Electromagnetic pulse (EMP) signals produced from explosives being fired have been reported in the literature for fifty years. When a gun is fired it produces an EMP muzzle blast signal. The strength and nature of these signals was first analyzed in the early 1970s, while the results were interesting, no follow-up studies were conducted. With modern detection and signal processing technology, we believe that these signals could be used to instantaneously locate guns of virtually all calibers as they fire. The objective of our one-year project was to establish the basic nature of these signals and their utility in the concept of electromagnetic targeting of guns.

  9. ORION laser target diagnosticsa)

    Science.gov (United States)

    Bentley, C. D.; Edwards, R. D.; Andrew, J. E.; James, S. F.; Gardner, M. D.; Comley, A. J.; Vaughan, K.; Horsfield, C. J.; Rubery, M. S.; Rothman, S. D.; Daykin, S.; Masoero, S. J.; Palmer, J. B.; Meadowcroft, A. L.; Williams, B. M.; Gumbrell, E. T.; Fyrth, J. D.; Brown, C. R. D.; Hill, M. P.; Oades, K.; Wright, M. J.; Hood, B. A.; Kemshall, P.

    2012-10-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics.

  10. ORION laser target diagnostics.

    Science.gov (United States)

    Bentley, C D; Edwards, R D; Andrew, J E; James, S F; Gardner, M D; Comley, A J; Vaughan, K; Horsfield, C J; Rubery, M S; Rothman, S D; Daykin, S; Masoero, S J; Palmer, J B; Meadowcroft, A L; Williams, B M; Gumbrell, E T; Fyrth, J D; Brown, C R D; Hill, M P; Oades, K; Wright, M J; Hood, B A; Kemshall, P

    2012-10-01

    The ORION laser facility is one of the UK's premier laser facilities which became operational at AWE in 2010. Its primary mission is one of stockpile stewardship, ORION will extend the UK's experimental plasma physics capability to the high temperature, high density regime relevant to Atomic Weapons Establishment's (AWE) program. The ORION laser combines ten laser beams operating in the ns regime with two sub ps short pulse chirped pulse amplification beams. This gives the UK a unique combined long pulse/short pulse laser capability which is not only available to AWE personnel but also gives access to our international partners and visiting UK academia. The ORION laser facility is equipped with a comprehensive suite of some 45 diagnostics covering optical, particle, and x-ray diagnostics all able to image the laser target interaction point. This paper focuses on a small selection of these diagnostics. PMID:23126904

  11. LLE review. Quarterly report, January 1994--March 1994, Volume 58

    Energy Technology Data Exchange (ETDEWEB)

    Simon, A. [ed.

    1994-07-01

    This volume of the LLE Review, covering the period Jan - Mar 1994, contains articles on backlighting diagnostics; the effect of electron collisions on ion-acoustic waves and heat flow; using PIC code simulations for analysis of ultrashort laser pulses interacting with solid targets; creating a new instrument for characterizing thick cryogenic layers; and a description of a large-aperture ring amplifier for laser-fusion drivers. Three of these articles - backlighting diagnostics; characterizing thick cryogenic layers; and large-aperture ring amplifier - are directly related to the OMEGA Upgrade, now under construction. Separate abstracts have been prepared for articles from this report.

  12. LLE review quarterly report, July--September 1991. Volume 48

    Energy Technology Data Exchange (ETDEWEB)

    Jaanimagi, P.A. [ed.

    1991-12-31

    This volume of the LLE Review, contains articles describing the results of imploding-target burnthrough experiments using smoothing by spectral dispersion (SSD), and a practical nonlocal model for electron transport in laser plasmas. The section on advanced technology includes a report on explosion fraction measurements of water-cooled xenon flashlamps, results on perfluorinated copolymer coatings for high-power laser applications, and a time-resolved study of surface disordering of Pb(110). A brief report reviewing the projects from the high school summer student program is also included. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  13. LLE Review Quarterly Report (April-June 1987). Volume 31

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, W. [Univ. of Rochester, NY (United States)

    1987-06-01

    This volume of the LLE Review, covering the period April-June 1987, contains a summary of the recent high-density campaign on the OMEGA laser system; a report on the absorption and radiation of energy from spherically irradiated targets; and a computer model describing the source of hot spots in the OMEGA laser. The section on advanced technology has reports on a method for accurately measuring the phase of a high power laser and the development of an extremely bright and compact laser. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  14. LLE review. Quarterly report, April 1997--June 1997. Volume 71

    International Nuclear Information System (INIS)

    This volume of the LLE Review, covering the period April-June 1997, includes an article discussing the results from recent experiments performed on OMEGA. These experiments used a new beam-smoothing device-distributed polarization rotators-in concert with existing techniques to improve the on-target uniformity of each beam. The result of this improved radiation uniformity was a substantive reduction in imprinting-the nonuniformity caused by the laser. A novel way to study the time dependence of this imprinting is also presented in this article

  15. LLE review. Quarterly report, April 1997--June 1997. Volume 71

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    This volume of the LLE Review, covering the period April-June 1997, includes an article discussing the results from recent experiments performed on OMEGA. These experiments used a new beam-smoothing device-distributed polarization rotators-in concert with existing techniques to improve the on-target uniformity of each beam. The result of this improved radiation uniformity was a substantive reduction in imprinting-the nonuniformity caused by the laser. A novel way to study the time dependence of this imprinting is also presented in this article.

  16. LLE Review Quarterly Report (April-June 1986). Volume 27

    Energy Technology Data Exchange (ETDEWEB)

    Yaakobi, B. [Univ. of Rochester, NY (United States)

    1986-06-01

    This volume of the LLE Review, covering the period April-June 1986, contains reports on GDL and OMEGA laser activities; analysis of neutron diagnostic methods of compressed laser targets; modeling of non-local heat flow in laser-heated plasmas; and development~ in advanced technology areas at LLE: protective polymeric coatings for nonlinear optical materials, time-resolved observation of electron-phonon relaxation in copper, and non-contact electro-optic sampling of high-speed electrical wave forms with a gallium-arsenide injection laser. Finally, the National Laser Users Facility activities for this period are summarized.

  17. LLE Review Quarterly Report (October-December 1987). Volume 33

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, W. [Univ. of Rochester, NY (United States)

    1987-09-01

    This volume of the LLE Review, covering the period October-December 1987, contains descriptions of the implementation of distributed phase plates for improved irradiation uniformity and the implementation of a cryogenic target capability on the OMEGA facility. The section on advanced technology has reports on the design and optimization of recombination x-ray lasers and a near-infrared dichroic dye for use in both active and passive liquid-crystal devices. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  18. Targeting of Antibodies using Aptamers

    OpenAIRE

    Missailidis, Sotiris

    2003-01-01

    The chapter presents a methodology for the rapid selection of aptamers against antibody targets. It is a detailed account of the various methodological steps that describe the selection of aptamers, including PCR steps, buffers to be used, target immobilisation, partitioning and amplification of aptamers, clonning and sequencing, to results in high affinity and specificity ligands for the chosen target antibody.

  19. After treat-to-target

    DEFF Research Database (Denmark)

    Wakefield, Richard J; D'Agostino, Maria Antonietta; Naredo, Esperanza;

    2012-01-01

    rheumatologists who have recently formed a research network - the Targeted Ultrasound Initiative (TUI) group. The statement proposes that targeting therapy to PD activity provides superior outcomes compared with treating to clinical targets alone and introduces the rationale for a new randomised trial using...

  20. Skin aging: are adipocytes the next target?

    Science.gov (United States)

    Kruglikov, Ilja L; Scherer, Philipp E

    2016-07-01

    Dermal white adipose tissue (dWAT) is increasingly appreciated as a special fat depot. The adipocytes in this depot exert a variety of unique effects on their surrounding cells and can undergo massive phenotypic changes. Significant modulation of dWAT content can be observed both in intrinsically and extrinsically aged skin. Specifically, skin that has been chronically photo-damaged displays a reduction of the dWAT volume, caused by the replacement of adipocytes by fibrotic structures. This is likely to be caused by the recently uncovered process described as "adipocyte-myofibroblast transition" (AMT). In addition, contributions of dermal adipocytes to the skin aging processes are also indirectly supported by spatial correlations between the prevalence of hypertrophic scarring and the appearance of signs of skin aging in different ethnic groups. These observations could elevate dermal adipocytes to prime targets in strategies aimed at counteracting skin aging. PMID:27434510

  1. Design of a liquid hydrogen target system

    International Nuclear Information System (INIS)

    An internal liquid hydrogen target is described for use with intermediate energy light ion beams. As a result, certain safety features are required to prevent a possible hydrogen explosion within the beamline or cyclotron. These safety features include an acoustical delay line which slows the hydrogen gas shock wave and a fast closing valve which shuts before any large volume of escaping gas reaches it. Other safety devices which reduce the changes of cell breakage and quickly shut off various ignition sources are discussed. Also described is a device involving a variable heat load which is coupled directly to the cryocondenser and is used to continually monitor and stabilize the pressure and temperature of the liquid hydrogen. (orig.)

  2. Petroleum supply annual 1994. Volume 1

    International Nuclear Information System (INIS)

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1994 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1994, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Below is a description of each section in Volume 1 of the PSA

  3. Petroleum supply annual 1994. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-22

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1994 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1994, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Below is a description of each section in Volume 1 of the PSA.

  4. Petroleum supply annual 1993. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1993 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1993, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Below is a description of each section in Volume 1 of the PSA.

  5. Physiology of cell volume regulation in vertebrates

    DEFF Research Database (Denmark)

    Hoffmann, Else K; Lambert, Ian H; Pedersen, Stine F

    2009-01-01

    cases, activation of volume regulatory osmolyte transport. After acute swelling, cell volume is regulated by the process of regulatory volume decrease (RVD), which involves the activation of KCl cotransport and of channels mediating K(+), Cl(-), and taurine efflux. Conversely, after acute shrinkage...... and their regulation by, e.g., membrane deformation, ionic strength, Ca(2+), protein kinases and phosphatases, cytoskeletal elements, GTP binding proteins, lipid mediators, and reactive oxygen species, upon changes in cell volume. We also discuss the nature of the upstream elements in volume sensing in vertebrate...

  6. LLE Review Quarterly Report (October-December 1999). Volume 81

    Energy Technology Data Exchange (ETDEWEB)

    Radha, P. B. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics

    1999-12-01

    This volume of the LLE Review, covering the period October–December 1999, includes a report on the stability of direct-drive NIF capsules. V. N. Goncharov, R. Betti, J. A. Delettrez, P. W. McKenty, S. Skupsky, and R. P. J. Town examine the conditions under which direct-drive NIF capsules ignite. Their numerical study uses two-dimensional hydrodynamic simulations in conjunction with a model that includes the various mechanisms that can influence target performance. Inner-surface roughness of the DT ice of the direct-drive cryogenic capsules and laser nonuniformities have been identified as the principal seeds of the instabilities that can potentially quench ignition. The authors conclude that a target gain greater than 10 can be achieved for a realistic inner-surface ice roughness when beam smoothing with 2-D SSD and a bandwidth greater than 0.5 THz is used.

  7. Phantom investigation of 3D motion-dependent volume aliasing during CT simulation for radiation therapy planning

    Directory of Open Access Journals (Sweden)

    Varchena Vladimir

    2007-02-01

    Full Text Available Abstract Purpose To quantify volumetric and positional aliasing during non-gated fast- and slow-scan acquisition CT in the presence of 3D target motion. Methods Single-slice fast, single-slice slow, and multi-slice fast scan helical CTs were acquired of dynamic spherical targets (1 and 3.15 cm in diameter, embedded in an anthropomorphic phantom. 3D target motions typical of clinically observed tumor motion parameters were investigated. Motion excursions included ± 5, ± 10, and ± 15 mm displacements in the S-I direction synchronized with constant displacements of ± 5 and ± 2 mm in the A-P and lateral directions, respectively. For each target, scan technique, and motion excursion, eight different initial motion-to-scan phase relationships were investigated. Results An anticipated general trend of target volume overestimation was observed. The mean percentage overestimation of the true physical target volume typically increased with target motion amplitude and decreasing target diameter. Slow-scan percentage overestimations were larger, and better approximated the time-averaged motion envelope, as opposed to fast-scans. Motion induced centroid misrepresentation was greater in the S-I direction for fast-scan techniques, and transaxial direction for the slow-scan technique. Overestimation is fairly uniform for slice widths Conclusion Non-gated CT imaging of targets describing clinically relevant, 3D motion results in aliased overestimation of the target volume and misrepresentation of centroid location, with little or no correlation between the physical target geometry and the CT-generated target geometry. Slow-scan techniques are a practical method for characterizing time-averaged target position. Fast-scan techniques provide a more reliable, albeit still distorted, target margin.

  8. Phantom investigation of 3D motion-dependent volume aliasing during CT simulation for radiation therapy planning

    International Nuclear Information System (INIS)

    To quantify volumetric and positional aliasing during non-gated fast- and slow-scan acquisition CT in the presence of 3D target motion. Single-slice fast, single-slice slow, and multi-slice fast scan helical CTs were acquired of dynamic spherical targets (1 and 3.15 cm in diameter), embedded in an anthropomorphic phantom. 3D target motions typical of clinically observed tumor motion parameters were investigated. Motion excursions included ± 5, ± 10, and ± 15 mm displacements in the S-I direction synchronized with constant displacements of ± 5 and ± 2 mm in the A-P and lateral directions, respectively. For each target, scan technique, and motion excursion, eight different initial motion-to-scan phase relationships were investigated. An anticipated general trend of target volume overestimation was observed. The mean percentage overestimation of the true physical target volume typically increased with target motion amplitude and decreasing target diameter. Slow-scan percentage overestimations were larger, and better approximated the time-averaged motion envelope, as opposed to fast-scans. Motion induced centroid misrepresentation was greater in the S-I direction for fast-scan techniques, and transaxial direction for the slow-scan technique. Overestimation is fairly uniform for slice widths < 5 mm, beyond which there is gross overestimation. Non-gated CT imaging of targets describing clinically relevant, 3D motion results in aliased overestimation of the target volume and misrepresentation of centroid location, with little or no correlation between the physical target geometry and the CT-generated target geometry. Slow-scan techniques are a practical method for characterizing time-averaged target position. Fast-scan techniques provide a more reliable, albeit still distorted, target margin

  9. Reduced central blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Bendtsen, F; Henriksen, Jens Henrik Sahl; Sørensen, T I;

    1989-01-01

    The pathogenesis of ascites formation in cirrhosis is uncertain. It is still under debate whether the effective blood volume is reduced (underfilling theory) or whether the intravascular compartment is expanded (overflow theory). This problem has not yet been solved because of insufficient tools...... for measuring the central blood volume. We have developed a method that enables us to determine directly the central blood volume, i.e., the blood volume in the heart cavities, lungs, and central arterial tree. In 60 patients with cirrhosis and 16 control subjects the central blood volume was assessed according...... to the kinetic theory as the product of cardiac output and mean transit time of the central vascular bed. Central blood volume was significantly smaller in patients with cirrhosis than in controls (mean 21 vs. 27 ml/kg estimated ideal body weight, p less than 0.001; 25% vs. 33% of the total blood volume, p less...

  10. Comparison of Hippocampal Volume in Dementia Subtypes

    International Nuclear Information System (INIS)

    Aims. To examine the relationship between different types of dementia and hippocampal volume. Methods. Hippocampal volume was measured using FL3D sequence magnetic resonance imaging in 26 Alzheimer's, vascular dementia, mixed dementia, and normal pressure hydrocephalus patients and 15 healthy controls and also hippocampal ratio, analyzed. Minimental scale was used to stratify patients on cognitive function impairments. Results. Hippocampal volume and ratio was reduced by 25% in Alzheimer's disease, 21% in mixed dementia, 11% in vascular dementia and 5% in normal pressure hydrocephalus in comparison to control. Also an asymmetrical decrease in volume of left hippocampus was noted. The severity of dementia increased in accordance to decreasing hippocampal volume. Conclusion. Measurement in hippocampal volume may facilitate in differentiating different types of dementia and in disease progression. There was a correlation between hippocampal volume and severity of cognitive impairment

  11. Hypoxia targeting copper complexes

    International Nuclear Information System (INIS)

    The importance and incidence of tumour hypoxia, its measurement and current treatments available, including pharmacological and radiopharmacological methods of targeting hypoxia, are discussed. A variety of in vitro and in vivo methods for imposing hypoxia have been developed and are reviewed. Copper, its chemistry, biochemistry and radiochemistry, the potential for use of copper radionuclides and its use to date in this field is considered with particular reference to the thiosemicarbazones. Their biological activity, metal chelation, in vitro and in vivo studies of their radiocopper complexes and the potential for their use as hypoxia targeting radiopharmaceuticals is described. The reduction of the copper(II) complex to copper(l), its pivotal importance in their biological behaviour, and the potential for manipulation of this to effect hypoxia selectivity are described. An in vitro method for assessing the hypoxia selectivity of radiopharmaceuticals is reported. The rapid deoxygenation and high viability of a mammalian cell culture in this system is discussed and factors which may affect the cellular uptake of a radiopharmaceutical are described. The design, synthesis and complexation with copper and radiocopper of a range of bis(thiosemicarbazones) is reported. Synthesis of these compounds is simple giving high yields of pure products. The characteristics of the radiocopper complexes (64Cu) including lipophilicity and redox activity are reported (reduction potentials in the range -0.314 - -0.590 V). High cellular uptakes of the radiocopper complexes of the ligands, in hypoxic and normoxic EMT6 and CHO320 cells, were observed. Extremes of selectivity are shown ranging from the hypoxia selective 64Cu(II)ATSM to normoxic cell selective 64Cu(II)GTS. The selectivities observed are compared with the physico chemical characteristics of the complexes. A good correlation exists between selectivity of the complex and its Cu(II)/Cu(I) reduction potential, with hypoxia

  12. Hypoxia targeting copper complexes

    Energy Technology Data Exchange (ETDEWEB)

    Dearling, J.L

    1998-11-01

    The importance and incidence of tumour hypoxia, its measurement and current treatments available, including pharmacological and radiopharmacological methods of targeting hypoxia, are discussed. A variety of in vitro and in vivo methods for imposing hypoxia have been developed and are reviewed. Copper, its chemistry, biochemistry and radiochemistry, the potential for use of copper radionuclides and its use to date in this field is considered with particular reference to the thiosemicarbazones. Their biological activity, metal chelation, in vitro and in vivo studies of their radiocopper complexes and the potential for their use as hypoxia targeting radiopharmaceuticals is described. The reduction of the copper(II) complex to copper(l), its pivotal importance in their biological behaviour, and the potential for manipulation of this to effect hypoxia selectivity are described. An in vitro method for assessing the hypoxia selectivity of radiopharmaceuticals is reported. The rapid deoxygenation and high viability of a mammalian cell culture in this system is discussed and factors which may affect the cellular uptake of a radiopharmaceutical are described. The design, synthesis and complexation with copper and radiocopper of a range of bis(thiosemicarbazones) is reported. Synthesis of these compounds is simple giving high yields of pure products. The characteristics of the radiocopper complexes ({sup 64}Cu) including lipophilicity and redox activity are reported (reduction potentials in the range -0.314 - -0.590 V). High cellular uptakes of the radiocopper complexes of the ligands, in hypoxic and normoxic EMT6 and CHO320 cells, were observed. Extremes of selectivity are shown ranging from the hypoxia selective {sup 64}Cu(II)ATSM to normoxic cell selective {sup 64}Cu(II)GTS. The selectivities observed are compared with the physico chemical characteristics of the complexes. A good correlation exists between selectivity of the complex and its Cu(II)/Cu(I) reduction potential

  13. Time course and predictive factors for lung volume reduction following stereotactic ablative radiotherapy (SABR) of lung tumors

    International Nuclear Information System (INIS)

    Stereotactic ablative volume reduction (SAVR) is a potential alternative to lung-volume reduction surgery in patients with severe emphysema and excessive surgical risk. Having previously observed a dose-volume response for localized lobar volume reduction after stereotactic ablative radiotherapy (SABR) for lung tumors, we investigated the time course and factors associated with volume reduction. We retrospectively identified 70 eligible patients receiving lung tumor SABR during 2007-2013. We correlated lobar volume reduction (relative to total, bilateral lung volume [TLV]) with volume receiving high biologically effective doses (VXXBED3) and other pre-treatment factors in all patients, and measured the time course of volume changes on 3-month interval CT scans in patients with large V60BED3 (n = 21, V60BED3 ≥4.1 % TLV). Median CT follow-up was 15 months. Median volume reduction of treated lobes was 4.5 % of TLV (range 0.01–13.0 %), or ~9 % of ipsilateral lung volume (ILV); median expansion of non-target adjacent lobes was 2.2 % TLV (−4.6–9.9 %; ~4 % ILV). Treated lobe volume reduction was significantly greater with larger VXXBED3 (XX = 20–100 Gy, R2 = 0.52–0.55, p < 0.0001) and smaller with lower pre-treatment FEV1% (R2 = 0.11, p = 0.005) in a multivariable linear model. Maximum volume reduction was reached by ~12 months and persisted. We identified a multivariable model for lobar volume reduction after SABR incorporating dose-volume and pre-treatment FEV1% and characterized its time course. The online version of this article (doi:10.1186/s13014-016-0616-8) contains supplementary material, which is available to authorized users

  14. Magnetic targeted drug delivery

    Directory of Open Access Journals (Sweden)

    Timothy Wiedmann

    2009-10-01

    Full Text Available Lung cancer is the most common cause of death from cancer in both men and women. Treatment by intravenous or oral administration of chemotherapy agents results in serious and often treatment-limiting side effects. Delivery of drugs directly to the lung by inhalation of an aerosol holds the promise of achieving a higher concentration in the lung with lower blood levels. To further enhance the selective lung deposition, it may be possible to target deposition by using external magnetic fields to direct the delivery of drug coupled to magnetic particles. Moreover, alternating magnetic fields can be used to induce particle heating, which in turn controls the drug release rate with the appropriate thermal sensitive material.With this goal, superparamagetic nanoparticles (SPNP were prepared and characterized, and enhanced magnetic deposition was demonstrated in vitro and in vivo. SPNPs were also incorporated into a lipid-based/SPNP aerosol formulation, and drug release was shown to be controlled by thermal activation. Because of the inherent imaging potential of SPNPs, this use of nanotechnology offers the possibility of coupling the diagnosis of lung cancer to drug release, which perhaps will ultimately provide the “magic bullet” that Paul Ehrlich originally sought.

  15. LLE Review Quarterly Report (January-March 2002). Volume 90

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, William R. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics

    2002-03-01

    This volume of the LLE Review, covering January-March 2002, features “First Results from Cryogenic Target Implosions on OMEGA” by C. Stoeckl et al. (p. 49). This article describes initial results from direct-drive spherical cryogenic target implosions on the 60-beam OMEGA laser system. These experiments are part of the scientific base leading to direct-drive ignition implosions planned for the National Ignition Facility (NIF). Results shown include neutron yield, secondary-neutron and proton yields, the time of peak neutron emission, and both time-integrated and time-resolved x-ray images of the imploding core. The experimental values are compared with 1-D numerical simulations. The target with an ice-layer nonuniformity of srms = 9 mm showed 30% of the 1-D predicted neutron yield. These initial results are encouraging for future cryogenic implosions on OMEGA and the NIF. Other articles in this issue are titled the following: Equation-of-State Measurements of Porous Materials on OMEGA: Numerical Modeling; Observations of Modulated Shock Waves in Solid Targets Driven by Spatially Modulated Laser Beams; Time-Dependent Electron Thermal Flux Inhibition in direct-Drive Laser Implosions; Precision Spectral Sculpting of Broadband FM Pulses Amplified in a Narrowband Medium; Electric-Field-Induced Motion of Polymer Cholesteric Liquid Crystal Flakes in a Moderately Conductive Fluid; and, Femtosecond Response of a Freestanding LT-GaAs Photoconductive Switch.

  16. ATF2 Proposal Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Grishanov, B.I.; Logachev, P.; Podgorny, F.; Telnov, V.; /Novosibirsk, IYF; Angal-Kalinin, D.; Jones, J.; Kalinin, A.; /Daresbury; Napoly, O.; Payet, J.; /DAPNIA, Saclay; Braun, H.H.; Schulte, D.; Zimmermann, F.; /CERN; Appleby, R.; Barlow, R.; Bailey, I.; Jenner, L.; Jones, R.; Kourevlev, G.; /Cockcroft Inst.; Elsen, E.; Vogel, V.; Walker, N.; /DESY

    2006-02-27

    For achieving the high luminosity required at the International Linear Collider (ILC), it is critical to focus the beams to nanometer size with the ILC Beam Delivery System (BDS), and to maintain the beam collision with a nanometer-scale stability. To establish the technologies associated with this ultra-high precision beam handling, it has been proposed to implement an ILC-like final focus optics in an extension of the existing extraction beamline of ATF at KEK. The ATF is considered to be the best platform for this exercise, since it provides an adequate ultra-low emittance electron beam in a manner dedicated to the development of ILC. The two major goals for this facility, called ATF2, are: (A) Achievement of a 37 nm beam size, and (B) control of beam position down to 2 nm level. The scientific justification for the ATF2 project and its technical design have been described in Volume 1 of the ATF2 Proposal [1]. We present here Volume 2 of the ATF2 Proposal, in which we present specifics of the construction plans and the group organization to execute the research programs at ATF2. The sections in this report have been authored by relevant ATF2 subgroups within the International ATF Collaboration. The time line of the project is described in Section 2. Section 3 discuss the structure of the international collaboration. Sections 4 and 5 discuss budget considerations, which are presented as well as the design and construction tasks to be shared by the international collaboration at ATF2. Concluding remarks have been contributed by Dr. Ewan Paterson, Chair of the International Collaboration Board of the ATF collaboration.

  17. [Plasma osmolarity and cerebral volume].

    Science.gov (United States)

    Boulard, G

    2001-02-01

    Under normal physiological conditions, the osmolarity of extracellular fluids (ECFs) and natremia are controlled by two regulatory mechanisms modulating the water balance and sodium outflow from information collected by the osmoreceptors and baroreceptors, respectively. As well, under normal physiological conditions, water and electrolytes of brain ECFs are secreted by the endothelial cells of brain capillaries. Furthermore, isotonicity is present on both sides of the blood-brain barrier. In the event of systemic osmolarity disorders, water transport subject to osmosis laws occurs at the level of the blood-brain barrier. In the case of plasmatic hyperosmolarity cerebral dehydration is observed, while cerebral edema occurs in the contrary case. However, plasmatic osmolarity disorders have less effect on the cerebral volume when their introduction is slow. Experimentation in acute conditions shows that measured variations of the cerebral water content are lower than calculated variations, thus suggesting the existence of an adaptive mechanism, that is, the cerebral osmoregulation which limits the variation of the volume of brain cells by modulating their osmoactive molecule content. These osmoactive molecules are, on the one hand, the electrolytes, which are early and rapidly mobilized, and, on the other hand, the organic osmoles (amino acids, etc.), whose secretion is slower and delayed. This phenomenon should be taken into account in the treatment of osmolarity disorders. Thus, the related-risk of treatment for natremia disorders is therapeutic reversal of the osmotic gradient at the level of the blood-brain barrier. This reversal, which corresponds to a second osmotic stress, requires the implementation of a new procedure of cerebral osmoregulation in the opposite direction of the preceding one. As successive osmotic stresses decrease the effectiveness of brain osmoregulation, the risk for cerebral dehydration and pontine myelinolysis increases when the treatment

  18. Radiotherapy planning for glioblastoma based on a tumor growth model: Improving target volume delineation

    CERN Document Server

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

    2013-01-01

    Glioblastoma are known to infiltrate the brain parenchyma instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In clinical practice, a uniform margin is applied to account for microscopic spread of disease. The current treatment planning procedure can potentially be improved by accounting for the anisotropy of tumor growth: Anatomical barriers such as the falx cerebri represent boundaries for migrating tumor cells. In addition, tumor cells primarily spread in white matter and infiltrate gray matter at lower rate. We investigate the use of a phenomenological tumor growth model for treatment planning. The model is based on the Fisher-Kolmogorov equation, which formalizes these growth characteristics and estimates the spatial distribution of tumor cells in normal appearing regions of the brain...

  19. Quantitation of 211At in small volumes for evaluation of targeted radiotherapy in animal models

    International Nuclear Information System (INIS)

    We have evaluated SPECT and two planar imaging methods, geometric mean (GM) and buildup factor (BF), for their potential to quantitate in vivo 211At distributions in rat spinal subarachnoid spaces using phantom studies. The use of medium-energy collimators and the small diameter (3 mm) of the subarachnoid space complicate quantitation. Net activities from distributions in various backgrounds were obtained using a large region of interest with background subtraction. Results showed quantitation accuracy within 10% for SPECT and BF in low backgrounds increasing to 25% at higher background levels while GM errors ranged from 20 to 45%. We have also obtained images of [211At]astatide distributions, administered intrathecally, in rats

  20. The ADVANCE project: Formal evaluation of the targeted deployment. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    The ADVANCE familiar driver test provided a small sample of drivers familiar with their local road network and patterns of recurring congestion with an opportunity to drive a vehicle equipped with the ADVANCE dynamic route guidance system for a period of two weeks of normal use. On the basis of this test experience, drivers were asked to evaluate the ADVANCE system and to assess the value of features for future in-vehicle route guidance systems. This test involved 80 volunteer households living in the ADVANCE test area in northwest suburban Chicago; 110 drivers from these households used the ADVANCE vehicle and responded to both baseline (pre-test) and post-test surveys. Thirty two of these drivers participated in focus groups. Drivers also maintained written logs describing their rerouting experiences with the ADVANCE system.

  1. Windowless target: Design of the XT-ADS spallation target

    International Nuclear Information System (INIS)

    The design of the XT-ADS spallation target is performed within the European integrated project EUROTRANS (FP6 Contract FI6W-516520) that has started in April 2005. At the current status of the spallation target design process, the boundary conditions for the spallation target loop with respect to the XT-ADS performance requirements and the design of the subcritical core and primary system have been established. The next steps will concentrate on further development of the spallation target nozzle, the vacuum and spallation product confinement system and the pumping, LIDAR (LIght Detection And Ranging) and cooling system

  2. Site Environmental Report for 2009, Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Suying

    2010-08-19

    Volume II of the Site Environmental Report for 2009 is provided by Ernest Orlando Lawrence Berkeley National Laboratory as a supplemental appendix to Volume I, which contains the body of the report. Volume II contains the environmental monitoring and sampling data used to generate summary results of routine and nonroutine sampling at the Laboratory, except for groundwater sampling data, which may be found in the reports referred to in Chapter 4 of Volume I. The results from sample collections are more comprehensive in Volume II than in Volume I: for completeness, all results from sample collections that began or ended in calendar year (CY) 2009 are included in this volume. However, the samples representing CY 2008 data have not been used in the summary results that are reported in Volume I. (For example, although ambient air samples collected on January 6, 2009, are presented in Volume II, they represent December 2008 data and are not included in Table 4-2 in Volume I.) When appropriate, sampling results are reported in both conventional and International System (SI) units. For some results, the rounding procedure used in data reporting may result in apparent differences between the numbers reported in SI and conventional units. (For example, stack air tritium results reported as < 1.5 Bq/m3 are shown variously as < 39 and < 41 pCi/m3. Both of these results are rounded correctly to two significant digits.)

  3. Predicting Nonauditory Adverse Radiation Effects Following Radiosurgery for Vestibular Schwannoma: A Volume and Dosimetric Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hayhurst, Caroline; Monsalves, Eric; Bernstein, Mark; Gentili, Fred [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada); Heydarian, Mostafa; Tsao, May [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Schwartz, Michael [Radiation Oncology Program and Division of Neurosurgery, Sunnybrook Hospital, Toronto (Canada); Prooijen, Monique van [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Millar, Barbara-Ann; Menard, Cynthia [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Kulkarni, Abhaya V. [Division of Neurosurgery, Hospital for Sick Children, University of Toronto (Canada); Laperriere, Norm [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Zadeh, Gelareh, E-mail: Gelareh.Zadeh@uhn.on.ca [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada)

    2012-04-01

    Purpose: To define clinical and dosimetric predictors of nonauditory adverse radiation effects after radiosurgery for vestibular schwannoma treated with a 12 Gy prescription dose. Methods: We retrospectively reviewed our experience of vestibular schwannoma patients treated between September 2005 and December 2009. Two hundred patients were treated at a 12 Gy prescription dose; 80 had complete clinical and radiological follow-up for at least 24 months (median, 28.5 months). All treatment plans were reviewed for target volume and dosimetry characteristics; gradient index; homogeneity index, defined as the maximum dose in the treatment volume divided by the prescription dose; conformity index; brainstem; and trigeminal nerve dose. All adverse radiation effects (ARE) were recorded. Because the intent of our study was to focus on the nonauditory adverse effects, hearing outcome was not evaluated in this study. Results: Twenty-seven (33.8%) patients developed ARE, 5 (6%) developed hydrocephalus, 10 (12.5%) reported new ataxia, 17 (21%) developed trigeminal dysfunction, 3 (3.75%) had facial weakness, and 1 patient developed hemifacial spasm. The development of edema within the pons was significantly associated with ARE (p = 0.001). On multivariate analysis, only target volume is a significant predictor of ARE (p = 0.001). There is a target volume threshold of 5 cm3, above which ARE are more likely. The treatment plan dosimetric characteristics are not associated with ARE, although the maximum dose to the 5th nerve is a significant predictor of trigeminal dysfunction, with a threshold of 9 Gy. The overall 2-year tumor control rate was 96%. Conclusions: Target volume is the most important predictor of adverse radiation effects, and we identified the significant treatment volume threshold to be 5 cm3. We also established through our series that the maximum tolerable dose to the 5th nerve is 9 Gy.

  4. LLE Review Quarterly Report (October-December 2001). Volume 89

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, William R. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics

    2001-12-01

    This volume of the LLE Review, covering October-December 2001, features “Time-Integrated Light Images of OMEGA Implosions” by P. Morley and W. Seka (p. 1). E. Kowaluk initiated this project for aesthetic rather than scientific reasons when he began taking visible light photographs of imploding OMEGA targets. These beautiful images are used to communicate LLE’s mission to the general public. A closer examination of the images revealed a one-to-one correspondence between the bright spots in the image and each of the 60 laser beams. The intensity of the bright spots has been related to refraction and absorption in the plasma surrounding the imploding target. These photographs are now proving to be the basis of a new laser-plasma interaction diagnostic. Other articles in this volume are titled the following: Analytical Model of Nonlinear, Single-Mode, Classical Rayleigh-Taylor Instability at Arbitrary Atwood Numbers; A High-Pass Phase Plate Design for OMEGA and the NIF; Advanced Tritium Recovery System; Establishing Links Between Single Gold Nanoparticles Buried Inside SiO2 Thin Film and 351-nm Pulsed-Laser-Damage Morphology; Resistive Switching Dynamics in Current-Biased Y-Ba-Cu-O Microbridges Excited by Nanosecond Electrical Pulses; and, Properties of Amorphous Carbon Films.

  5. Facility target insert shielding assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mocko, Michal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-06

    Main objective of this report is to assess the basic shielding requirements for the vertical target insert and retrieval port. We used the baseline design for the vertical target insert in our calculations. The insert sits in the 12”-diameter cylindrical shaft extending from the service alley in the top floor of the facility all the way down to the target location. The target retrieval mechanism is a long rod with the target assembly attached and running the entire length of the vertical shaft. The insert also houses the helium cooling supply and return lines each with 2” diameter. In the present study we focused on calculating the neutron and photon dose rate fields on top of the target insert/retrieval mechanism in the service alley. Additionally, we studied a few prototypical configurations of the shielding layers in the vertical insert as well as on the top.

  6. The OLYMPUS internal hydrogen target

    Energy Technology Data Exchange (ETDEWEB)

    Bernauer, J.C., E-mail: bernauer@mit.edu [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA 02139 (United States); Carassiti, V.; Ciullo, G. [Istituto Nazionale di Fisica Nucleare and Università, 44100 Ferrara (Italy); Henderson, B.S. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA 02139 (United States); Ihloff, E.; Kelsey, J. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA 02139 (United States); MIT-Bates Linear Accelerator Center, Middleton, MA 01949 (United States); Lenisa, P. [Istituto Nazionale di Fisica Nucleare and Università, 44100 Ferrara (Italy); Milner, R. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA 02139 (United States); MIT-Bates Linear Accelerator Center, Middleton, MA 01949 (United States); Schmidt, A. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA 02139 (United States); Statera, M. [Istituto Nazionale di Fisica Nucleare and Università, 44100 Ferrara (Italy)

    2014-08-01

    An internal hydrogen target system was developed for the OLYMPUS experiment at DESY, in Hamburg, Germany. The target consisted of a long, thin-walled, tubular cell within an aluminum scattering chamber. Hydrogen entered at the center of the cell and exited through the ends, where it was removed from the beamline by a multistage pumping system. A cryogenic coldhead cooled the target cell to counteract heating from the beam and increase the density of hydrogen in the target. A fixed collimator protected the cell from synchrotron radiation and the beam halo. A series of wakefield suppressors reduced heating from beam wakefields. The target system was installed within the DORIS storage ring and was successfully operated during the course of the OLYMPUS experiment in 2012. Information on the design, fabrication, and performance of the target system is reported.

  7. The OLYMPUS Internal Hydrogen Target

    CERN Document Server

    Bernauer, J C; Ciullo, G; Henderson, B S; Ihloff, E; Kelsey, J; Lenisa, P; Milner, R; Schmidt, A; Statera, M

    2014-01-01

    An internal hydrogen target system was developed for the OLYMPUS experiment at DESY, in Hamburg, Germany. The target consisted of a long, thin-walled, tubular cell within an aluminum scattering chamber. Hydrogen entered at the center of the cell and exited through the ends, where it was removed from the beamline by a multistage pumping system. A cryogenic coldhead cooled the target cell to counteract heating from the beam and increase the density of hydrogen in the target. A fixed collimator protected the cell from synchrotron radiation and the beam halo. A series of wakefield suppressors reduced heating from beam wakefields. The target system was installed within the DORIS storage ring and was successfully operated during the course of the OLYMPUS experiment in 2012. Information on the design, fabrication, and performance of the target system is reported.

  8. Oxide Fiber Targets at ISOLDE

    CERN Document Server

    Köster, U; Carminati, D; Catherall, R; Cederkäll, J; Correia, J G; Crepieux, B; Dietrich, M; Elder, K; Fedosseev, V; Fraile-Prieto, L M; Franchoo, S; Fynbo, H O U; Georg, U; Giles, T; Joinet, A; Jonsson, O C; Kirchner, R; Lau, C; Lettry, Jacques; Maier, H J; Mishin, V I; Oinonen, M; Peräjärvi, K; Ravn, H L; Rinaldi, T; Santana-Leitner, M; Wahl, U; Weissman, L

    2003-01-01

    Many elements are rapidly released from oxide matrices. Some oxide powder targets show a fast sintering, thus losing their favorable release characteristics. Loosely packed oxyde fiber targets are less critical since they may maintain their open structure even when starting to fuse together at some contact points. The experience with various oxyde fiber targets (titania, zirconia, ceria and thoria) used in the last years at ISOLDE is reviewed. For short-lived isotopes of Cu, Ga and Xe the zirconia and ceria targets respectively provided significantly higher yields than any other target (metal foils, oxide powders, etc.) tested before. Titania fibers, which were not commercially available, were produced in a relic process by impregnation of a rayon felt in a titanium chloride solution and subsequent calcination by heating the dried felt in air. Thoria fibers were obtained either by the same process or by burning commercial gas lantern mantle cloth. In the future a beryllia fiber target could be used to produce...

  9. Relationship between stroke volume and pulse pressure during blood volume perturbation: a mathematical analysis.

    Science.gov (United States)

    Bighamian, Ramin; Hahn, Jin-Oh

    2014-01-01

    Arterial pulse pressure has been widely used as surrogate of stroke volume, for example, in the guidance of fluid therapy. However, recent experimental investigations suggest that arterial pulse pressure is not linearly proportional to stroke volume. However, mechanisms underlying the relation between the two have not been clearly understood. The goal of this study was to elucidate how arterial pulse pressure and stroke volume respond to a perturbation in the left ventricular blood volume based on a systematic mathematical analysis. Both our mathematical analysis and experimental data showed that the relative change in arterial pulse pressure due to a left ventricular blood volume perturbation was consistently smaller than the corresponding relative change in stroke volume, due to the nonlinear left ventricular pressure-volume relation during diastole that reduces the sensitivity of arterial pulse pressure to perturbations in the left ventricular blood volume. Therefore, arterial pulse pressure must be used with care when used as surrogate of stroke volume in guiding fluid therapy.

  10. An estimate of global glacier volume

    Directory of Open Access Journals (Sweden)

    A. Grinsted

    2013-01-01

    Full Text Available I assess the feasibility of using multivariate scaling relationships to estimate glacier volume from glacier inventory data. Scaling laws are calibrated against volume observations optimized for the specific purpose of estimating total global glacier ice volume. I find that adjustments for continentality and elevation range improve skill of area–volume scaling. These scaling relationships are applied to each record in the Randolph Glacier Inventory, which is the first globally complete inventory of glaciers and ice caps. I estimate that the total volume of all glaciers in the world is 0.35 ± 0.07 m sea level equivalent, including ice sheet peripheral glaciers. This is substantially less than a recent state-of-the-art estimate. Area–volume scaling bias issues for large ice masses, and incomplete inventory data are offered as explanations for the difference.

  11. Volume-effect in radiation therapy part one: volume-effect and tumour; L'effet volume en radiotherapie premiere partie: effet volume et tumeur

    Energy Technology Data Exchange (ETDEWEB)

    Huchet, A.; Wu, J. [Hopital Europeen Georges-Pompidou (AP-HP), Service de Radiotherapie, 75 - Paris (France); Caudry, M.; Trouette, R.; Vendrely, V.; Causse, N.; Recaldini, L.; Dahan, O.; Maire, J.P. [Hopital Saint-Andre, Service de Radiotherapie, 33 - Bordeaux (France); Belkacemi, Y. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiotherapie, 59 - Lille (France)

    2003-04-01

    Volume is an important parameter of radiation therapy. Local control is inversely related to tumor size and the complication rate increases with the importance of the irradiated volume. Although the effect of irradiated volume has been widely reported since the beginning of radiotherapy, it has been less studied than other radiation parameters such as dose, fractionation, or treatment duration. One of the first organ system in which the adverse effect of increased volume was well defined is the skin. Over the last twenty years, numerous mathematical models have been developed for different organs. In this report we will discuss the relation between irradiated volume and tumor control. In a second article we will study the impact of irradiated volume on radiation adverse effects. (authors)

  12. Reduced central blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Bendtsen, Flemming; Sørensen, T I;

    1989-01-01

    was inversely correlated to the systemic vascular resistance (r = -0.49, p less than 0.001), the latter being significantly reduced in the patient group. Patients with cirrhosis apparently are unable to maintain a normal central blood volume. This may be due to arteriolar vasodilation, portosystemic collateral......The pathogenesis of ascites formation in cirrhosis is uncertain. It is still under debate whether the effective blood volume is reduced (underfilling theory) or whether the intravascular compartment is expanded (overflow theory). This problem has not yet been solved because of insufficient tools...... for measuring the central blood volume. We have developed a method that enables us to determine directly the central blood volume, i.e., the blood volume in the heart cavities, lungs, and central arterial tree. In 60 patients with cirrhosis and 16 control subjects the central blood volume was assessed according...

  13. Targeting Nominal Income: A Note

    OpenAIRE

    Kenneth D. West

    1986-01-01

    This paper compares nominal income and monetary targets in a standard aggregate demand - aggregate supply framework. If the desirability of policies is measured by their effect on the unconditional variance of output, nominal income targeting is preferable if and only if the aggregate elasticity of demand for real balances is greater than one. This is precisely the opposite of the condition that in Bean (1984) is sufficient to make nominal income targeting preferable.This points out the impor...

  14. Nominal Income and Inflation Targeting

    OpenAIRE

    Arayssi, Mahmoud

    2014-01-01

    In this paper a macro- economic model in the area of monetary policy game theory is extended to one-sided dismissal rules concerning observed nominal output and inflation targets for the central banker. These rules specify firing the central banker if some observed policy targets have been exceeded. Such rules are shown to reduce inflationary bias if the central banker perceives her reappointment chances as being strong and is preferred to discretionary monetary policy. Various policy targets...

  15. Target properties and nuclear data

    International Nuclear Information System (INIS)

    The influence of the properties of the target on nuclear data was shown. In the case of targets consisting of fissionable material, this influence was demonstrated in experiments involving fission cross-section, average number of neutrons, and prompt fission neutron spectrum. The experimental methods for determining certain corrections were analysed. The method of tritium density determination for a solid target used as neutron source was likewise demonstrated. (author). 10 refs, 4 figs

  16. Learning About Intervention Target Zones

    OpenAIRE

    Klein, Michael W; Karen K. Lewis

    1991-01-01

    This paper provides a framework for evaluating how market participants' beliefs about foreign exchange target zones change as they learn about central bank intervention policy. In order to examine this behavior, we first generalize the standard target zone model to allow for intra-marginal intervention. Intra-marginal intervention implies that the position of market participants' beliefs about the target zone can be determined from their beliefs about the likelihood of intervention. As an app...

  17. Inertial-confinement-fusion targets

    International Nuclear Information System (INIS)

    Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques have been devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented

  18. 'Inflation Targeting and Inflation Persistence'

    OpenAIRE

    George J. Bratsiotis; Jakob Madsen; Christopher Martin

    2015-01-01

    This paper argues that the adoption of an inflation target reduces the persistence of inflation. We develop the theoretical literature on inflation persistence by introducing a Taylor rule for monetary policy into a model of persistence and showing that inflation targets reduce inflation persistence. We investigate changes in the time series properties of inflation in seven countries that introduced inflation targets in the late 1980s or early 1990s. We find that the persistenc...

  19. Heliophysics 3 Volume Paperback Set

    Science.gov (United States)

    Schrijver, Carolus J.; Siscoe, George L.

    2013-03-01

    Volume 1: Preface; 1. Prologue Carolus J. Schrijver and George L. Siscoe; 2. Introduction to heliophysics Thomas J. Bogdan; 3. Creation and destruction of magnetic field Matthias Rempel; 4. Magnetic field topology Dana W. Longcope; 5. Magnetic reconnection Terry G. Forbes; 6. Structures of the magnetic field Mark B. Moldwin, George L. Siscoe and Carolus J. Schrijver; 7. Turbulence in space plasmas Charles W. Smith; 8. The solar atmosphere Viggo H. Hansteen; 9. Stellar winds and magnetic fields Viggo H. Hansteen; 10. Fundamentals of planetary magnetospheres Vytenis M. Vasyliunas; 11. Solar-wind magnetosphere coupling: an MHD perspective Frank R. Toffoletto and George L. Siscoe; 12. On the ionosphere and chromosphere Tim Fuller-Rowell and Carolus J. Schrijver; 13. Comparative planetary environments Frances Bagenal; Bibliography; Index. Volume 2: Preface; 1. Perspective on heliophysics George L. Siscoe and Carolus J. Schrijver; 2. Introduction to space storms and radiation Sten Odenwald; 3. In-situ detection of energetic particles George Gloeckler; 4. Radiative signatures of energetic particles Tim Bastian; 5. Observations of solar and stellar eruptions, flares, and jets Hugh Hudson; 6. Models of coronal mass ejections and flares Terry Forbes; 7. Shocks in heliophysics Merav Opher; 8. Particle acceleration in shocks Dietmar Krauss-Varban; 9. Energetic particle transport Joe Giacalone; 10. Energy conversion in planetary magnetospheres Vytenis Vasyliunas; 11. Energization of trapped particles Janet Green; 12. Flares, CMEs, and atmospheric responses Tim Fuller-Rowell and Stanley C. Solomon; 13. Energetic particles and manned spaceflight Stephen Guetersloh and Neal Zapp; 14. Energetic particles and technology Alan Tribble; Appendix I. Authors and editors; List of illustrations; List of tables; Bibliography; Index. Volume 3: Preface; 1. Interconnectedness in heliophysics Carolus J. Schrijver and George L. Siscoe; 2. Long-term evolution of magnetic activity of Sun

  20. Target support for inertial confinement fusion

    International Nuclear Information System (INIS)

    General Atomics (GA) plays an important industrial support role for the US Inertial Confinement Fusion (ICF) program in the area of target technology. This includes three major activities: target fabrication support, target handling systems development, and target chamber design. The work includes target fabrication for existing ICF experiments, target and target system development for future experiments, and target research and target chamber design for experiments on future machines, such as the National Ignition Facility (NIF)