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Shiha M, Cygler JE, MacRae R, Heath E. 4D Monte Carlo dose reconstructions using surface motion measurements. Phys Med 2023; 114:103135. [PMID: 37738806 DOI: 10.1016/j.ejmp.2023.103135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/01/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023] Open
Abstract
PURPOSE To investigate the feasibility of a 4D Monte Carlo based dose reconstruction method to study the dosimetric impact of respiratory motion using surface motion measurements for patients undergoing VMAT treatments for Non-Small Cell Lung Cancer. METHODS The 4Ddefdosxyznrc/EGSnrc algorithm was used to reconstruct VMAT doses delivered to the patients using machine log files and respiratory traces measured with the RADPOS 4D dosimetry system. The RADPOS sensor was adhered to the patient's abdomen prior to each treatment fraction and its position was used as a surrogate for tumour motion. Treatment log files were synchronized with the patient respiratory traces. Patient specific respiratory models were generated from deformable registration of the inhale and exhale 4DCT images and the respiratory traces. The reconstructed doses were compared to planned doses calculated with DOSXYZnrc/EGSnrc on the average-intensity and the exhale phase CT images. RESULTS Respiratory motion measurements and log files were acquired for 2 patients over 5 treatment fractions each. The motion was predominantly along the anterior/posterior direction (A/P). The average respiratory amplitudes were 8.7 ± 2.7 mm and 10.0 ± 1.2 mm for Patient 1 and 2, respectively. Both patients displayed inter- and intra-fractional variations in the baseline position. Small inter-fractional differences were observed in the reconstructed doses for each patient. Differences between the reconstructed and planned doses were attributed to differences in organ volumes. CONCLUSION The 4D reconstruction method was successfully implemented for the two patients studied. Small differences between the planned and reconstructed doses were observed due to the small tumour motion of these patients.
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Affiliation(s)
- Meaghen Shiha
- Department of Physics, Carleton University, Ottawa, ON K1S 5B6, Canada.
| | - Joanna E Cygler
- Department of Physics, Carleton University, Ottawa, ON K1S 5B6, Canada; Department of Medical Physics, The Ottawa Hospital Cancer Centre, Ottawa, ON K1H 8L6, Canada; Department of Radiology, University of Ottawa, Ottawa, ON K1H 8L6, Canada
| | - Robert MacRae
- Department of Radiology, Division of Radiation Oncology, University of Ottawa, 501 Smyth Road, Ottawa, ON K1H8L6, Canada
| | - Emily Heath
- Department of Physics, Carleton University, Ottawa, ON K1S 5B6, Canada
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Lin YS, Morozov V, Kadry AR, Caffrey J, Chou WC. Reconstructing population exposures to acrylamide from human monitoring data using a pharmacokinetic framework. Chemosphere 2023; 331:138798. [PMID: 37137393 DOI: 10.1016/j.chemosphere.2023.138798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/17/2023] [Accepted: 04/26/2023] [Indexed: 05/05/2023]
Abstract
BACKGROUND Acrylamide toxicity involves several metabolic pathways. Thus, a panel of blood and urinary biomarkers for the evaluation of acrylamide exposure was deemed appropriate. OBJECTIVE The study was designed to evaluate daily acrylamide exposure in US adults via hemoglobin adducts and urinary metabolites using a pharmacokinetic framework. METHODS A cohort of 2798 subjects aged 20-79 was selected from the National Health and Nutrition Examination Survey (NHANES, 2013-2016) for analysis. Three acrylamide biomarkers including hemoglobin adducts of acrylamide in blood and two urine metabolites, N-Acetyl-S-(2-carbamoylethyl)cysteine (AAMA) and N-Acetyl-S-(2-carbamoyl-2-hydroxyethyl)-l-cysteine (GAMA) were used to estimate daily acrylamide exposure using validated pharmacokinetic prediction models. Multivariate regression models were also used to examine key factors in determining estimated acrylamide intake. RESULTS The estimated daily acrylamide exposure varied across the sampled population. Estimated acrylamide daily exposure was comparable among the three different biomarkers (median: 0.4-0.7 μg/kg/d). Cigarette smoking emerged as the leading contributor to the acquired acrylamide dose. Smokers had the highest estimated acrylamide intake (1.20-1.49 μg/kg/d) followed by passive smokers (0.47-0.61) and non-smokers (0.45-0.59). Several covariates, particularly, body mass index and race/ethnicity, played roles in determining estimated exposures. DISCUSSION Estimated daily acrylamide exposures among US adults using multiple acrylamide biomarkers were similar to populations reported elsewhere providing additional support for using the current approach in assessing acrylamide exposure. This analysis assumes that the biomarkers used indicate intake of acrylamide into the body, which is consistent with the substantial known exposures due to diet and smoking. Although this study did not explicitly evaluate background exposure arising from analytical or internal biochemical factors, these findings suggest that the use of multiple biomarkers may reduce uncertainties regarding the ability of any single biomarker to accurately represent actual systemic exposures to the agent. This study also highlights the value of integrating a pharmacokinetic approach into exposure assessments.
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Affiliation(s)
- Yu-Sheng Lin
- Office of Research and Development, U.S. EPA, Washington, DC, 20460, USA.
| | - Viktor Morozov
- Office of Research and Development, U.S. EPA, Washington, DC, 20460, USA
| | - Abdel-Razak Kadry
- University of Maryland, School of Public Health, College Park, MD, 20742, USA
| | - James Caffrey
- University of North Texas Health Science Center, Fort Worth, TX, 76107, USA
| | - Wei-Chun Chou
- University of Florida, Center for Environmental and Human Toxicology, Gainesville, FL, 32610, USA
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van Prooijen M, Chau L, Tsui G, Kelly V, Holwell M, Tadic T, Tsang DS, Krema H, Laperriere N. Simple and effective immobilization for radiation treatment of choroidal melanoma. Med Dosim 2023:S0958-3947(23)00023-7. [PMID: 37120386 DOI: 10.1016/j.meddos.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 03/03/2023] [Accepted: 03/11/2023] [Indexed: 05/01/2023]
Abstract
At our institution, patients diagnosed with choroidal melanoma requiring external beam radiation therapy are treated with two 6 MV volumetric-modulated arcs delivering 50 Gy over 5 daily fractions. The patient is immobilized using an Orfit head and neck mask and is directed to look at a light emitting diode (LED) during CT simulation and treatment to minimize eye movement. Patient positioning is checked with cone beam computed tomography (CBCT) daily. Translational and rotational displacements greater than 1 mm or 1° off the planned isocenter position are corrected using a Hexapod couch. The aim of this study is to verify that the mask system provides adequate immobilization and to verify our 2-mm planning target volume (PTV) margins are sufficient. Residual displacements provided by pretreatment verification and post-treatment CBCT data sets were used to assess the impact of patient mobility during treatment on the reconstructed delivered dose to the target and organs at risk. The PTV margin calculated using van Herk's method1 was used to assess patient motion plus other factors that affect treatment position, such as kV-MV isocenter coincidence. Patient position variations were small and were shown to not cause significant dose variations between the planned and reconstructed dose to the target and organs at risk. The PTV margin analysis showed patient translational motion alone required a PTV margin of 1 mm. Given other factors that affect treatment delivery accuracy, a 2-mm PTV margin was shown to be sufficient for treatment of 95% of our patients with 100% of dose delivered to the GTV. The mask immobilization with LED focus is robust and we showed a 2-mm PTV margin is adequate with this technique.
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Affiliation(s)
- Monique van Prooijen
- Department of Medical Physics, Princess Margaret Cancer Centre, Toronto, ON, M5G 1Z5, Canada.
| | - Lily Chau
- Department of Radiation Therapy, Princess Margaret Cancer Centre, Toronto, ON, M5G 2M9, Canada
| | - Grace Tsui
- Department of Radiation Therapy, Princess Margaret Cancer Centre, Toronto, ON, M5G 2M9, Canada
| | - Valerie Kelly
- Department of Radiation Therapy, Princess Margaret Cancer Centre, Toronto, ON, M5G 2M9, Canada
| | - Michael Holwell
- Department of Radiation Therapy, Princess Margaret Cancer Centre, Toronto, ON, M5G 2M9, Canada
| | - Tony Tadic
- Department of Medical Physics, University of Toronto, Princess Margaret Cancer Centre, Toronto, ON, M5G 1Z5, Canada; Department of Radiation Oncology, University of Toronto, Princess Margaret Cancer Centre, Toronto, ON, M5G 1Z5, Canada
| | - Derek S Tsang
- Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON, M5G 1Z5, Canada
| | - Hatem Krema
- Department of Ocular Oncology, Princess Margaret Cancer Centre/ UHN, University of Toronto, Toronto, ON, M5G 2M9, Canada
| | - Normand Laperriere
- Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, ON, M5G 1Z5, Canada
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Woda C, Hiller M, Ademola JA, Bugrov NG, Degteva MO, Napier B. Luminescence dosimetry for evaluation of the external exposure in Metlino, upper Techa River valley, Southern Urals, Russia: Analysis of new results. Appl Radiat Isot 2023; 193:110618. [PMID: 36608624 DOI: 10.1016/j.apradiso.2022.110618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 11/22/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Luminescence dosimetry was applied in the former settlement of Metlino, Southern Urals, Russia as part of a full-scale study to validate the Techa River Dosimetry System (TRDS) 2016 for the upper Techa River region. The village, which was evacuated in 1956, was located 7 km downstream of the release point of liquid radioactive waste by the Mayak plutonium facility. Several brick samples were taken from north-eastern and south-eastern walls of the granary, facing the former Techa river shoreline and floodplain. Samples were all taken at the same height and measured at different depths into the brick. For the majority of brick samples, good Optically Stimulated Luminescence properties of the quartz grains were observed. In some cases, however, strong levels of sensitization and/or signal recuperation were encountered which necessitated adjustment in the measurement protocols. Anthropogenic doses in bricks varied from 1.5 to 6.6 Gy and the horizontal profiles along both walls showed significant variation, which is explained on a qualitative basis. A dose depth profile is observed for selected samples, which is different from the dose depth profile measured and simulated for samples from the north-western wall of the granary in previous studies. This is qualitatively explained by the differences in source configuration.
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Affiliation(s)
- C Woda
- Helmholtz Zentrum München- German Research Center for Environmental Health, Institute of Radiation Medicine, D-85764, Neuherberg, Germany.
| | - M Hiller
- Independent Researcher, Augsburg, Germany
| | - J A Ademola
- Department of Physics, University of Ibadan, Ibadan, Nigeria
| | - N G Bugrov
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - M O Degteva
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - B Napier
- Pacific Northwest National Laboratory, Richland, WA, USA
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Grimbergen G, Pötgens GG, Eijkelenkamp H, Raaymakers BW, Intven MPW, Meijer GJ. Feasibility of delivered dose reconstruction for MR-guided SBRT of pancreatic tumors with fast, real-time 3D cine MRI. Radiother Oncol 2023; 182:109506. [PMID: 36736589 DOI: 10.1016/j.radonc.2023.109506] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND PURPOSE In MR-guided SBRT of pancreatic cancer, intrafraction motion is typically monitored with (interleaved) 2D cine MRI. However, tumor surroundings are often not fully captured in these images, and motion might be distorted by through-plane movement. In this study, the feasibility of highly accelerated 3D cine MRI to reconstruct the delivered dose during MR-guided SBRT was assessed. MATERIALS AND METHODS A 3D cine MRI sequence was developed for fast, time-resolved 4D imaging, featuring a low spatial resolution that allows for rapid volumetric imaging at 430 ms. The 3D cines were acquired during the entire beam-on time of 23 fractions of online adaptive MR-guided SBRT for pancreatic tumors on a 1.5 T MR-Linac. A 3D deformation vector field (DVF) was extracted for every cine dynamic using deformable image registration. Next, these DVFs were used to warp the partial dose delivered in the time interval between consecutive cine acquisitions. The warped dose plans were summed to obtain a total delivered dose. The delivered dose was also calculated under various motion correction strategies. Key DVH parameters of the GTV, duodenum, small bowel and stomach were extracted from the delivered dose and compared to the planned dose. The uncertainty of the calculated DVFs was determined with the inverse consistency error (ICE) in the high-dose regions. RESULTS The mean (SD) relative (ratio delivered/planned) D99% of the GTV was 0.94 (0.06), and the mean (SD) relative D0.5cc of the duodenum, small bowel, and stomach were respectively 0.98 (0.04), 1.00 (0.07), and 0.98 (0.06). In the fractions with the lowest delivered tumor coverage, it was found that significant lateral drifts had occurred. The DVFs used for dose warping had a low uncertainty with a mean (SD) ICE of 0.65 (0.07) mm. CONCLUSION We employed a fast, real-time 3D cine MRI sequence for dose reconstruction in the upper abdomen, and demonstrated that accurate DVFs, acquired directly from these images, can be used for dose warping. The reconstructed delivered dose showed only a modest degradation of tumor coverage, mostly attainable to baseline drifts. This emphasizes the need for motion monitoring and development of intrafraction treatment adaptation solutions, such as baseline drift corrections.
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Owens CA, Rigaud B, Ludmir EB, Gupta AC, Shrestha S, Paulino AC, Smith SA, Peterson CB, Kry SF, Lee C, Henderson TO, Armstrong GT, Brock KK, Howell RM. Development and validation of a population-based anatomical colorectal model for radiation dosimetry in late effects studies of survivors of childhood cancer. Radiother Oncol 2022; 176:118-126. [PMID: 36063983 PMCID: PMC9845018 DOI: 10.1016/j.radonc.2022.08.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 08/10/2022] [Accepted: 08/24/2022] [Indexed: 01/19/2023]
Abstract
PURPOSE The purposes of this study were to develop and integrate a colorectal model that incorporates anatomical variations of pediatric patients into the age-scalable MD Anderson Late Effects (MDA-LE) computational phantom, and validate the model for pediatric radiation therapy (RT) dose reconstructions. METHODS Colorectal contours were manually derived from whole-body non-contrast computed tomography (CT) scans of 114 pediatric patients (age range: 2.1-21.6 years, 74 males, 40 females). One contour was used for an anatomical template, 103 for training and 10 for testing. Training contours were used to create a colorectal principal component analysis (PCA)-based statistical shape model (SSM) to extract the population's dominant deformations. The SSM was integrated into the MDA-LE phantom. Geometric accuracy was assessed between patient-specific and SSM contours using several overlap metrics. Two alternative colorectal shapes were generated using the first 17 dominant modes of the PCA-based SSM. Dosimetric accuracy was assessed by comparing colorectal doses from test patients' CT-based RT plans (ground truth) with reconstructed doses for the mean and two alternative models in age-matched MDA-LE phantoms. RESULTS When using all 103 PCA modes, the mean (min-max) Dice similarity coefficient, distance-to-agreement and Hausdorff distance between the patient-specific and reconstructed contours for the test patients were 0.89 (0.85-0.91), 2.1 mm (1.7-3.0), and 8.6 mm (5.7-14.3), respectively. The average percent difference between reconstructed and ground truth mean and maximum colorectal doses for the mean (alternative 1, 2) model were 6.3% (8.1%, 6.1%) and 4.4% (4.3%, 4.7%), respectively. CONCLUSIONS We developed, validated and integrated a colorectal PCA-based SSM into the MDA-LE phantom and demonstrated its dosimetric performance for accurate pediatric RT dose reconstruction.
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Affiliation(s)
- Constance A Owens
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Graduate Program in Medical Physics, Houston, TX, USA.
| | - Bastien Rigaud
- The University of Texas MD Anderson Cancer Center, Department of Imaging Physics, Houston, TX, USA
| | - Ethan B Ludmir
- The University of Texas MD Anderson Cancer Center, Department of Radiation Oncology, Houston, TX, USA; The University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX, USA
| | - Aashish C Gupta
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Graduate Program in Medical Physics, Houston, TX, USA
| | - Suman Shrestha
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Graduate Program in Medical Physics, Houston, TX, USA
| | - Arnold C Paulino
- The University of Texas MD Anderson Cancer Center, Department of Radiation Oncology, Houston, TX, USA
| | - Susan A Smith
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA
| | - Christine B Peterson
- The University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX, USA
| | - Stephen F Kry
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Graduate Program in Medical Physics, Houston, TX, USA
| | - Choonsik Lee
- National Cancer Institute, Division of Cancer Epidemiology and Genetics, Bethesda, MD, USA
| | - Tara O Henderson
- The University of Chicago, Department of Pediatrics, Chicago, IL, USA
| | - Gregory T Armstrong
- St. Jude Children's Research Hospital, Department of Epidemiology and Cancer Control, Memphis, TN, USA
| | - Kristy K Brock
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; The University of Texas MD Anderson Cancer Center, Department of Imaging Physics, Houston, TX, USA
| | - Rebecca M Howell
- The University of Texas MD Anderson Cancer Center, Department of Radiation Physics, Houston, TX, USA; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Graduate Program in Medical Physics, Houston, TX, USA.
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Xiong Y, Rabe M, Nierer L, Kawula M, Corradini S, Belka C, Riboldi M, Landry G, Kurz C. Assessment of intrafractional prostate motion and its dosimetric impact in MRI-guided online adaptive radiotherapy with gating. Strahlenther Onkol 2022. [PMID: 36151215 DOI: 10.1007/s00066-022-02005-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/04/2022] [Indexed: 10/14/2022]
Abstract
PURPOSE This study aimed to evaluate the intrafractional prostate motion captured during gated magnetic resonance imaging (MRI)-guided online adaptive radiotherapy for prostate cancer and analyze its impact on the delivered dose as well as the effect of gating. METHODS Sagittal 2D cine-MRI scans were acquired at 4 Hz during treatment at a ViewRay MRIdian (ViewRay Inc., Oakwood Village, OH, USA) MR linac. Prostate shifts in anterior-posterior (AP) and superior-inferior (SI) directions were extracted separately. Using the static dose cloud approximation, the planned fractional dose was shifted according to the 2D gated motion (residual motion in gating window) to estimate the delivered dose by superimposing and averaging the shifted dose volumes. The dose of a hypothetical non-gated delivery was reconstructed similarly using the non-gated motion. For the clinical target volume (CTV), rectum, and bladder, dose-volume histogram parameters of the planned and reconstructed doses were compared. RESULTS In total, 174 fractions (15.7 h of cine-MRI) from 10 patients were evaluated. The average (±1 σ) non-gated prostate motion was 0.6 ± 1.0 mm in the AP and 0.0 ± 0.6 mm in the SI direction with respect to the centroid position of the gating boundary. 95% of the shifts were within [-3.5, 2.7] mm in the AP and [-2.9, 3.2] mm in the SI direction. For the gated treatment and averaged over all fractions, CTV D98% decreased by less than 2% for all patients. The rectum and the bladder D2% increased by less than 3% and 0.5%, respectively. Doses reconstructed for gated and non-gated delivery were similar for most fractions. CONCLUSION A pipeline for extraction of prostate motion during gated MRI-guided radiotherapy based on 2D cine-MRI was implemented. The 2D motion data enabled an approximate estimation of the delivered dose. For the majority of fractions, the benefit of gating was negligible, and clinical dosimetric constraints were met, indicating safety of the currently adopted gated MRI-guided treatment workflow.
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Ehrbar S, Braga Käser S, Chamberlain M, Krayenbühl J, Wilke L, Mayinger M, Garcia Schüler H, Guckenberger M, Andratschke N, Tanadini-Lang S. MR-guided beam gating: Residual motion, gating efficiency and dose reconstruction for stereotactic treatments of the liver and lung. Radiother Oncol 2022; 174:101-108. [PMID: 35839937 DOI: 10.1016/j.radonc.2022.07.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 06/01/2022] [Accepted: 07/07/2022] [Indexed: 01/10/2023]
Abstract
PURPOSE This study aims to investigate the efficiency and the geometric as well as the dosimetric benefit of magnetic-resonance guided beam gating for stereotactic treatments in moving organs. METHOD Patients treated with MR-guided (MRIdian system) SBRT for lung (n = 10) and liver (n = 10) targets were analyzed. Breath-hold gating was performed based on lesion tracking in sagittal cine MRI images. The target offset from the geometric center of the gating window with and without gating was evaluated. A dose reconstruction workflow based on convolution of these 2D position-probability maps and the daily 3D dose distribution was used to estimate the daily delivered dose including motion. The dose to the clinical target volume (CTV) and to a 2-cm ring structure around the planning target volume were evaluated. RESULTS The applied gating protocol resulted in a mean (±standard deviation) gating efficiency of 55%±16%. Over all patients, the mean target offset (2D-root-mean-square error) was 8.3 ± 4.3 mm, which reduced to 2.4 ± 0.6 mm during gating. The dose reconstruction showed a mean deviation in CTV coverage (D95) from the static plans of -1.7%±1.8% with gating and -12.0%±8.4% if no gating would have been used. The mean dose (Dmean) in the ring structure, with respect to the static plans, showed mean deviations of -0.1%±0.3% with gating and -1.6%±1.8% without gating. CONCLUSION The MRIdian system enables gating based on the inner anatomy and the implemented dose reconstruction workflow demonstrated geometric robust delivery of the planned radiation doses.
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Affiliation(s)
- Stefanie Ehrbar
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland.
| | - Sarah Braga Käser
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Madalyne Chamberlain
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Jérôme Krayenbühl
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Lotte Wilke
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Michael Mayinger
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Helena Garcia Schüler
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Matthias Guckenberger
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Nicolaus Andratschke
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
| | - Stephanie Tanadini-Lang
- Department of Radiation Oncology, University Hospital Zürich and University of Zürich, Zürich, Switzerland
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Akhavanallaf A, Mohammadi R, Shiri I, Salimi Y, Arabi H, Zaidi H. Personalized brachytherapy dose reconstruction using deep learning. Comput Biol Med 2021; 136:104755. [PMID: 34388458 DOI: 10.1016/j.compbiomed.2021.104755] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/05/2021] [Accepted: 08/05/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND PURPOSE Accurate calculation of the absorbed dose delivered to the tumor and normal tissues improves treatment gain factor, which is the major advantage of brachytherapy over external radiation therapy. To address the simplifications of TG-43 assumptions that ignore the dosimetric impact of medium heterogeneities, we proposed a deep learning (DL)-based approach, which improves the accuracy while requiring a reasonable computation time. MATERIALS AND METHODS We developed a Monte Carlo (MC)-based personalized brachytherapy dosimetry simulator (PBrDoseSim), deployed to generate patient-specific dose distributions. A deep neural network (DNN) was trained to predict personalized dose distributions derived from MC simulations, serving as ground truth. The paired channel input used for the training is composed of dose distribution kernel in water medium along with the full-volumetric density maps obtained from CT images reflecting medium heterogeneity. RESULTS The predicted single-dwell dose kernels were in good agreement with MC-based kernels serving as reference, achieving a mean relative absolute error (MRAE) and mean absolute error (MAE) of 1.16 ± 0.42% and 4.2 ± 2.7 × 10-4 (Gy.sec-1/voxel), respectively. The MRAE of the dose volume histograms (DVHs) between the DNN and MC calculations in the clinical target volume were 1.8 ± 0.86%, 0.56 ± 0.56%, and 1.48 ± 0.72% for D90, V150, and V100, respectively. For bladder, sigmoid, and rectum, the MRAE of D5cc between the DNN and MC calculations were 2.7 ± 1.7%, 1.9 ± 1.3%, and 2.1 ± 1.7%, respectively. CONCLUSION The proposed DNN-based personalized brachytherapy dosimetry approach exhibited comparable performance to the MC method while overcoming the computational burden of MC calculations and oversimplifications of TG-43.
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Affiliation(s)
- Azadeh Akhavanallaf
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva 4, Switzerland
| | - Reza Mohammadi
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Isaac Shiri
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva 4, Switzerland
| | - Yazdan Salimi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva 4, Switzerland
| | - Hossein Arabi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva 4, Switzerland
| | - Habib Zaidi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva 4, Switzerland; Geneva University Neurocenter, Geneva University, CH-1205, Geneva, Switzerland; Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, 9700 RB, Groningen, Netherlands; Department of Nuclear Medicine, University of Southern Denmark, DK-500, Odense, Denmark.
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Jaccard M, Ehrbar S, Miralbell R, Hagen T, Koutsouvelis N, Poulsen P, Rouzaud M, Tanadini-Lang S, Tsoutsou P, Guckenberger M, Zilli T. Single-fraction prostate stereotactic body radiotherapy: Dose reconstruction with electromagnetic intrafraction motion tracking. Radiother Oncol 2021; 156:145-52. [PMID: 33310011 DOI: 10.1016/j.radonc.2020.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 02/07/2023]
Abstract
PURPOSE To reconstruct the dose delivered during single-fraction urethra-sparing prostate stereotactic body radiotherapy (SBRT) accounting for intrafraction motion monitored by intraprostatic electromagnetic transponders (EMT). METHODS We analyzed data of 15 patients included in the phase I/II "ONE SHOT" trial and treated with a single fraction of 19 Gy to the planning target volume (PTV) and 17 Gy to the urethra planning risk volume. During delivery, prostate motion was tracked with implanted EMT. SBRT was interrupted when a 3-mm threshold was trespassed and corrected unless the offset was transient. Motion-encoded reconstructed (MER) plans were obtained by splitting the original plans into multiple sub-beams with isocenter shifts based on recorded EMT positions, mimicking prostate motion during treatment. We analyzed intrafraction motion and compared MER to planned doses. RESULTS The median EMT motion range (±SD) during delivery was 0.26 ± 0.09, 0.22 ± 0.14 and 0.18 ± 0.10 cm in the antero-posterior, supero-inferior, and left-right axes, respectively. Treatment interruptions were needed for 8 patients because of target motion beyond limits in the antero-posterior (n = 6) and/or supero-inferior directions (n = 4). Comparing MER vs. original plan there was a median relative dose difference of -1.9% (range, -7.9 to -1.0%) and of +0.5% (-0.3-1.7%) for PTV D98% and D2%, respectively. The clinical target volume remained sufficiently covered with a median D98% difference of -0.3% (-1.6-0.5%). Bladder and rectum dosimetric parameters showed significant differences between original and MER plans, but mostly remained within acceptable limits. CONCLUSIONS The dosimetric impact of intrafraction prostate motion was minimal for target coverage for single-fraction prostate SBRT with real-time electromagnetic tracking combined with beam gating.
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11
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Imae T, Haga A, Watanabe Y, Takenaka S, Shiraki T, Nawa K, Ogita M, Takahashi W, Yamashita H, Nakagawa K, Abe O. Retrospective dose reconstruction of prostate stereotactic body radiotherapy using cone-beam CT and a log file during VMAT delivery with flattening-filter-free mode. Radiol Phys Technol 2020; 13:238-48. [PMID: 32656744 DOI: 10.1007/s12194-020-00574-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 07/01/2020] [Accepted: 07/06/2020] [Indexed: 10/23/2022]
Abstract
This study aimed to reconstruct the dose distribution of single fraction of stereotactic body radiotherapy for patients with prostate cancer using cone-beam computed tomography (CBCT) and a log file during volumetric-modulated arc therapy (VMAT) delivery with flattening-filter-free (FFF) mode. Twenty patients with clinically localized prostate cancer were treated with FFF-VMAT, and projection images for in-treatment CBCT (iCBCT) imaging were concomitantly acquired with a log file. A D95 dose of 36.25 Gy in five fractions was prescribed to each planning target volume (PTV) on each treatment planning CT (pCT). Deformed pCT (dCT) was obtained from the iCBCT using a hybrid deformable image registration algorithm. Dose distributions on the dCT were calculated using Pinnacle3 v9.10 by converting the log file data to Pinnacle3 data format using an in-house software. Dose warping was performed by referring to deformation vector fields calculated from pCT and dCT. Reconstructed dose distribution was compared with that of the original plan. Dose differences between the original and reconstructed dose distributions were within 3% at the isocenter and observed in PTV and organ-at-risk (OAR) regions. Differences in OAR regions were relatively larger than those in the PTV, presumably because OARs were more deformed than the PTV. Therefore, our method can be used successfully to reconstruct the dose distributions of one fraction using iCBCT and a log file during FFF-VMAT delivery.
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12
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Vanhanen A, Poulsen P, Kapanen M. Dosimetric effect of intrafraction motion and different localization strategies in prostate SBRT. Phys Med 2020; 75:58-68. [PMID: 32540647 DOI: 10.1016/j.ejmp.2020.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 05/04/2020] [Accepted: 06/06/2020] [Indexed: 01/02/2023] Open
Abstract
The aim of this study was to evaluate the dosimetric effect of continuous motion monitoring based localization (Calypso, Varian Medical Systems), gating and intrafraction motion correction in prostate SBRT. Delivered doses were modelled by reconstructing motion inclusive dose distributions for different localization strategies. Actually delivered dose (strategy A) utilized initial Calypso localization, CBCT and additional pre-treatment motion correction by kV-imaging and Calypso, and gating during the irradiation. The effect of gating was investigated by simulating non-gated treatments (strategy B). Additionally, non-gated and single image-guided (CBCT) localization was simulated (strategy C). A total of 308 fractions from 22 patients were reconstructed. The dosimetric effect was evaluated by comparing motion inclusive target and risk organ dose-volume parameters to planned values. Motion induced dose deficits were seen mainly in PTV and CTV to PTV margin regions, whereas CTV dose deficits were small in all strategies: mean ± SD difference in CTVD99% was -0.3 ± 0.4%, -0.4 ± 0.6% and -0.7 ± 1.2% in strategies A, B and C, respectively. Largest dose deficits were seen in individual fractions for strategy C (maximum dose reductions were -29.0% and -7.1% for PTVD95% and CTVD99%, respectively). The benefit of gating was minor, if additional motion correction was applied immediately prior to irradiation. Continuous motion monitoring based localization and motion correction ensured the target coverage and minimized the OAR exposure for every fraction and is recommended to use in prostate SBRT. The study is part of clinical trial NCT02319239.
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Affiliation(s)
- A Vanhanen
- Department of Oncology, Unit of Radiotherapy, Tampere University Hospital, POB-2000, 33521 Tampere, Finland; Department of Medical Physics, Medical Imaging Center, Tampere University Hospital, POB-2000, 33521 Tampere, Finland.
| | - P Poulsen
- Department of Oncology and Danish Center for Particle Therapy, Aarhus University Hospital, Palle Juul-Jensens Boulevard 25, Entrance B3, 8200 Aarhus N, Denmark
| | - M Kapanen
- Department of Oncology, Unit of Radiotherapy, Tampere University Hospital, POB-2000, 33521 Tampere, Finland; Department of Medical Physics, Medical Imaging Center, Tampere University Hospital, POB-2000, 33521 Tampere, Finland
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13
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Woda C, Hiller M, Ulanowski A, Bugrov NG, Degteva MO, Ivanov O, Romanov S, Tschiersch J, Shinonaga T. Luminescence dosimetry for evaluation of the external exposure in Metlino, upper Techa River valley, due to the shore of the Metlinsky Pond: A feasibility study. J Environ Radioact 2020; 214-215:106152. [PMID: 32063284 DOI: 10.1016/j.jenvrad.2019.106152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 12/20/2019] [Accepted: 12/22/2019] [Indexed: 06/10/2023]
Abstract
Luminescence dosimetry was performed using bricks from the former settlement of Metlino, Southern Urals, Russia, to investigate the feasibility of validating the Techa River Dosimetry System (TRDS) 2016 for the shore of the Metlinsky Pond, upper Techa River region. TRDS is a code for estimating external and internal doses for members of the Extended Techa River Cohort. Several brick samples were taken from the north-western wall of the granary, facing the Metlinsky Pond. Samples were measured at different heights and at different depths into the bricks. Dating of the granary was performed by analyzing well shielded bricks. Assessment of the gamma dose-rate at the sample positions was done by thermoluminescent dosimeters and the dose-rate in front of the granary mapped with a dose-rate meter. Anthropogenic doses in bricks vary from 0.8 to 1.7 Gy and show an increase with sampling height. A similar height profile is observed for the current gamma dose-rate, which is compatible with the results of the dose-rate mapping. Implications for validating the TRDS are discussed.
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Affiliation(s)
- C Woda
- Helmholtz Zentrum München, Institute of Radiation Medicine, 85764, Neuherberg, Germany.
| | - M Hiller
- Independent Researcher, Stolberg, Germany
| | - A Ulanowski
- Helmholtz Zentrum München, Institute of Radiation Medicine, 85764, Neuherberg, Germany; International Atomic Energy Agency, IAEA Environmental Laboratories, A-2444, Seibesdorf, Austria
| | - N G Bugrov
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - M O Degteva
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - O Ivanov
- National Research Center «Kurchatov Institute», Moscow, 123182, Russia
| | - S Romanov
- Southern Urals Biophysics Institute, Ozyorsk, Russia
| | - J Tschiersch
- Helmholtz Zentrum München, Institute of Radiation Medicine, 85764, Neuherberg, Germany
| | - T Shinonaga
- Helmholtz Zentrum München, Former Institute of Radiation Protection, 85764, Neuherberg, Germany
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14
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Menten MJ, Mohajer JK, Nilawar R, Bertholet J, Dunlop A, Pathmanathan AU, Moreau M, Marshall S, Wetscherek A, Nill S, Tree AC, Oelfke U. Automatic reconstruction of the delivered dose of the day using MR-linac treatment log files and online MR imaging. Radiother Oncol 2020; 145:88-94. [PMID: 31931291 PMCID: PMC7191265 DOI: 10.1016/j.radonc.2019.12.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 12/11/2019] [Accepted: 12/15/2019] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND PURPOSE Anatomical changes during external beam radiotherapy prevent the accurate delivery of the intended dose distribution. Resolving the delivered dose, which is currently unknown, is crucial to link radiotherapy doses to clinical outcomes and ultimately improve the standard of care. MATERIAL AND METHODS In this study, we present a dose reconstruction workflow based on data routinely acquired during MR-guided radiotherapy. It employs 3D MR images, 2D cine MR images and treatment machine log files to calculate the delivered dose taking intrafractional motion into account. The developed pipeline was used to measure anatomical changes and assess their dosimetric impact in 89 prostate radiotherapy fractions delivered with a 1.5 T MR-linac at our institute. RESULTS Over the course of radiation delivery, the CTV shifted 0.6 mm ± 2.1 mm posteriorly and 1.3 mm ± 1.5 mm inferiorly. When extrapolating the dose changes in each case to 20 fractions, the mean clinical target volume D98% and clinical target volume D50% dose-volume metrics decreased by 1.1 Gy ± 1.6 Gy and 0.1 Gy ± 0.2 Gy, respectively. Bladder D3% did not change (0.0 Gy ± 1.2 Gy), while rectum D3% decreased by 1.0 Gy ± 2.0 Gy. Although anatomical changes and their dosimetric impact were small in the majority of cases, large intrafractional motion caused the delivered dose to substantially deviate from the intended plan in some fractions. CONCLUSIONS The presented end-to-end workflow is able to reliably, non-invasively and automatically reconstruct the delivered prostate radiotherapy dose by processing MR-linac treatment log files and online MR images. In the future, we envision this workflow to be adapted to other cancer sites and ultimately to enter widespread clinical use.
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Affiliation(s)
- Martin J Menten
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK.
| | - Jonathan K Mohajer
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Rahul Nilawar
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Jenny Bertholet
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Alex Dunlop
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Angela U Pathmanathan
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | | | | | - Andreas Wetscherek
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Simeon Nill
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Alison C Tree
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Uwe Oelfke
- Joint Department of Physics at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
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15
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Lowther NJ, Marsh SH, Louwe RJW. Quantifying the dose accumulation uncertainty after deformable image registration in head-and-neck radiotherapy. Radiother Oncol 2020; 143:117-125. [PMID: 32063377 DOI: 10.1016/j.radonc.2019.12.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/12/2019] [Accepted: 12/15/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE Deformable image registration (DIR) facilitated dose reconstruction and accumulation can be applied to assess delivered dose and verify the validity of the treatment plan during treatment. This retrospective study used in silico deformations based on clinically observed anatomical changes as ground truth to investigate the uncertainty of reconstructed and accumulated dose in head-and-neck radiotherapy (HNRT). MATERIALS AND METHODS A planning CT (pCT), cone beam CT (CBCT) from week one of treatment and three later CBCTs were selected for 12 HNRT patients. These images were used to generate in silico reference CBCTs and deformation vector fields (DVFs) as ground truth with B-spline DIR. Inverse consistency (IC) of voxels was assessed by determining their net displacement after successive application of the forward and backward DVF. The reconstructed dose based on demons DIR was compared to the ground truth to assess the structure-specific uncertainties of this DIR algorithm for inverse consistent and inverse inconsistent voxels. RESULTS Overall, 98.5% of voxels were inverse consistent with the 95% level of confidence range for dose reconstruction of a single fraction equal to [-2.3%; +2.1%], [-10.2%; +15.2%] and [-9.5%; +12.5%] relative to their planned dose for target structures, critical organs at risk (OARs) and non-critical OARs, respectively. Inverse inconsistent voxels generally showed a higher level of uncertainty. CONCLUSION The uncertainty in accumulated dose using DIR can be accurately quantified and incorporated in dose-volume histograms (DVHs). This method can be used to prospectively assess the adequacy of target coverage during treatment in an objective manner.
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Affiliation(s)
- Nicholas J Lowther
- Wellington Blood and Cancer Centre, Department of Radiation Oncology, Wellington, New Zealand; University of Canterbury, School of Physical and Chemical Sciences, Christchurch, New Zealand
| | - Steven H Marsh
- University of Canterbury, School of Physical and Chemical Sciences, Christchurch, New Zealand
| | - Robert J W Louwe
- Wellington Blood and Cancer Centre, Department of Radiation Oncology, Wellington, New Zealand.
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16
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Hancock S, Vo NTK, Goncharova RI, Seymour CB, Byun SH, Mothersill CE. One-Decade-Spanning transgenerational effects of historic radiation dose in wild populations of bank voles exposed to radioactive contamination following the chernobyl nuclear disaster. Environ Res 2020; 180:108816. [PMID: 31627157 DOI: 10.1016/j.envres.2019.108816] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/08/2019] [Accepted: 10/08/2019] [Indexed: 06/10/2023]
Abstract
The concept of historic radiation doses associated with accidental radioactive releases and their role in leading to radiation-induced non-targeted effects on affected wild animals are currently being evaluated. Previous research studying Fukushima butterfly, Chernobyl bird and fruit fly populations shows that the effects are transgenerational, underlined by the principles of genomic instability, and varied from one species to another. To further expand on the responses of and their sensitivity in different taxonomically distinct groups, the present study sought to reconstruct historic radiation doses and delineate their effects on bank voles (Clethrionomys glareolus) found within a 400-km radius of the Chernobyl Nuclear Power Plant meltdown site. Historic dose reconstruction from the whole-body dose rates for the bank vole samples for their parental generation at the time of radioactive release was performed. Relationships between the historic doses and cytogenetic aberrations and embryonic lethality were examined via graphical presentations. Results suggest that genomic instability develops at the historic dose range of 20-51 mGy while a radioadaptive response develops at the historic dose range of 51-356 mGy. The Linear No-Threshold (LNT) relationship was absent at historic doses of lower than 356 mGy at all generations. However, LNT was apparent when the very high historic dose of 10.28 Gy in one sampling year was factored into the dose response curve for the bank vole generation 21-22. It is worth being reminded that natural mutation accumulation and other environmental stressors outside the realm of dose effects could contribute to the observed effects in a multiple-stressor environment. Nevertheless, the consistent development of genomic instability and radio-adaptive response across generations and sampling sites unearths the utmost fundamental radiobiological principle of transgenerational non-targeted effects. As a result, it calls for better attention and regulation from global governing bodies of environmental health protection.
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Affiliation(s)
- Samuel Hancock
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada
| | - Nguyen T K Vo
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Roza I Goncharova
- Institute of Genetics and Cytology, National Academy of Sciences, Minsk, Belarus
| | - Colin B Seymour
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Soo Hyun Byun
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada
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Kemerink GJ, Kütterer G, Kicken PJ, van Engelshoven JMA, Simon KJ, Wildberger JE. The skin dose of pelvic radiographs since 1896. Insights Imaging 2019; 10:39. [PMID: 30923937 PMCID: PMC6439109 DOI: 10.1186/s13244-019-0710-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/23/2019] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES To derive conversions of antiquated exposure data into modern equivalents and to apply these in the assessment of the skin dose of pelvic radiographs since 1896. METHODS The literature 1896-2018 was searched for implicit and explicit dose information. The early implicit dose data contained now obsolete descriptions of radiation quality and quantity for long since disappeared X-ray systems of limited efficiency. Converting the old information into modern specifications was achieved using contemporary data and computer simulations. Final dose calculations were done with modern software. Explicit radiation doses of later date reported in old quantities and units were adapted according to current recommendations. RESULTS For the period before 1927 conversion algorithms for spark gap data and penetrometer hardnesses to high voltage could be derived. Electrical and X-ray efficiencies of several old röntgen systems were determined. Together they allowed reconstruction of 53 doses. After 1927 doses were generally explicitly specified; 114 were retrieved. Although an enormous spread was observed, the average skin dose was reduced by a factor of about 400. CONCLUSIONS Antiquated exposure data were successfully used for dose reconstruction. Extreme dose variability was a constant. Efforts to cut down doses were effective as skin doses went down from sub-erythema values to about one milligray.
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Affiliation(s)
- Gerrit J Kemerink
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands.
| | - Gerhard Kütterer
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Pierre J Kicken
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Jos M A van Engelshoven
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Kees J Simon
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Joachim E Wildberger
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debijelaan 25, 6229 HX, Maastricht, The Netherlands
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Bales K, Dewji S, Sanchez E. Comparison of neutron organ and effective dose coefficients for PIMAL stylized phantom in bent postures in standard irradiation geometries. Radiat Environ Biophys 2018; 57:375-393. [PMID: 30167867 DOI: 10.1007/s00411-018-0751-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
Neutron dose coefficients for standard irradiation geometries have been reported in International Commission on Radiological Protection (ICRP) Publication 116 for the ICRP Publication 110 adult reference phantoms. In the present work, organ and effective dose coefficients have been calculated for a receptor in both upright and articulated (bent) postures representing more realistic working postures exposed to a mono-energetic neutron radiation field. This work builds upon prior work by Dewji and co-workers comparing upright and bent postures for exposure to mono-energetic photon fields. Simulations were conducted using the Oak Ridge National Laboratory's articulated stylized adult phantom, "Phantom wIth Moving Arms and Legs" (PIMAL) software package, and the Monte Carlo N-Particle (MCNP) version 6.1.1 radiation transport code. Organ doses were compared for the upright and bent (45° and 90°) phantom postures for neutron energies ranging from 1 × 10- 9 to 20 MeV for the ICRP Publication 116 external exposure geometries-antero-posterior (AP), postero-anterior (PA), and left and right lateral (LLAT, RLAT). Using both male and female phantoms, effective dose coefficients were computed using ICRP Publication 103 methodology. The resulting coefficients for articulated phantoms were compared to those of the upright phantom. Computed organ and effective dose coefficients are discussed as a function of neutron energy, phantom posture, and source irradiation geometry. For example, it is shown here that for the AP and PA irradiation geometries, the differences in the organ coefficients between the upright and bent posture become more pronounced with increasing bending angle. In the AP geometry, the brain dose coefficients are expectedly higher in the bent postures than in the upright posture, while all other organs have lower dose coefficients, with the thyroid showing the greatest difference. Overall, the effective dose estimated for the upright phantom is more conservative than that for the articulated phantom, which may have ramifications in the estimation or reconstruction of radiation doses.
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Affiliation(s)
- K Bales
- Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Oak Ridge, TN, USA
- Department of Nuclear Engineering, University of Tennessee, Knoxville, Knoxville, TN, USA
| | - S Dewji
- Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Oak Ridge, TN, USA.
| | - E Sanchez
- Oak Ridge National Laboratory, Center for Radiation Protection Knowledge, Oak Ridge, TN, USA
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
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Ivanov DV, Shishkina EA, Osipov DI, Starichenko VI, Bayankin SN, Zhukovsky MV, Pryakhin EA. Otoliths as object of EPR dosimetric research. Radiat Environ Biophys 2018; 57:357-363. [PMID: 30324495 DOI: 10.1007/s00411-018-0758-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 10/06/2018] [Indexed: 06/08/2023]
Abstract
Otoliths are the organs which fish use for hearing and keeping balance. Otoliths are the most calcified tissues in the fish body. In contrast to bones, otoliths are not affected by remodeling and, therefore, they are expected to accumulate any dose from ionizing radiation during lifetime. Therefore, EPR dosimetry with fish otoliths could be an important tool for dose reconstruction in radiobiology and radioecology. It could also provide useful information remediation actions to de-contaminate waterbodies. Consequently, in the present study, otoliths of three contaminated fish species (roach (Rutilus rutilus), pike (Esox lucius) and perch (Perca Fluviatilis)) were examined with Electron Paramagnetic Resonance (EPR) spectroscopy. The fish were caught at storage reservoirs of liquid radioactive waste from Mayak PA and from the upper reach of the Techa River, which have been contaminated with different levels of radionuclide activity concentrations. It is shown that the radiation-induced EPR signal of otolith is stable and characterized by a linear dose response. However, the slope of the calibration curve (corresponding to the radiation sensitivity of the material) is not the same for different species; this may be caused by differences in mineralization. The reconstructed doses were found to be in the range from undetectable (in fish from the upper stream of the Techa River) up to 265 Gy (in roach from the most contaminated waterbody). In parallel, otoliths were measured with β-counter to detect 90Sr/90Y. Samples were also tested on the presence of alpha-emitters, but no alpha activity above background could be detected. However, a significant activity concentration of 90Sr was detected (from 1 × 101 to 2 × 104 Bq/g). The EPR doses measured correlated with the 90Sr activity concentration measured in the otolith samples.
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Affiliation(s)
- D V Ivanov
- M. N. Miheev Institute of Metal Physics, Urals Division of Russian Academy of Sciences, 18, S. Kovalevskaya Str., 620108, Yekaterinburg, Russia.
- Ural Federal University, 19, Mira Str., 620002, Yekaterinburg, Russia.
| | - E A Shishkina
- Urals Research Center for Radiation Medicine, 68A, Vorovsky Str., 454076, Chelyabinsk, Russia
- Chelyabinsk State University, 129, Bratiev Kashirinykh Str., 454001, Chelyabinsk, Russia
| | - D I Osipov
- Urals Research Center for Radiation Medicine, 68A, Vorovsky Str., 454076, Chelyabinsk, Russia
| | - V I Starichenko
- Institute of Plants and Animals Ecology, Urals Division of Russian Academy of Sciences, 202, 8 Marta Str., 620144, Yekaterinburg, Russia
| | - S N Bayankin
- Sverdlovsk Regional Oncology Clinic, 29, Soboleva Str., 620036, Yekaterinburg, Russia
| | - M V Zhukovsky
- Ural Federal University, 19, Mira Str., 620002, Yekaterinburg, Russia
- Institute of Industrial Ecology, Urals Division of Russian Academy of Sciences, 20a, S. Kovalevskaya Str., 620219, Yekaterinburg, Russia
| | - E A Pryakhin
- Urals Research Center for Radiation Medicine, 68A, Vorovsky Str., 454076, Chelyabinsk, Russia
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20
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Sun WZ, Zhang DD, Peng YL, Chen L, Kang DH, Wang B, Deng XW. Retrospective dosimetry study of intensity-modulated radiation therapy for nasopharyngeal carcinoma: measurement-guided dose reconstruction and analysis. Radiat Oncol 2018; 13:42. [PMID: 29544512 PMCID: PMC5856312 DOI: 10.1186/s13014-018-0993-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 03/07/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Conventional phantom-based planar dosimetry (2D-PBD) quality assurance (QA) using gamma pass rate (GP (%)) is inadequate to reflect clinically relevant dose error in intensity-modulated radiation therapy (IMRT), owing to a lack of information regarding patient anatomy and volumetric dose distribution. This study aimed to evaluate the dose distribution accuracy of IMRT delivery for nasopharyngeal carcinoma (NPC), which passed the 2D-PBD verification, using a measurement-guided 3D dose reconstruction (3D-MGR) method. METHODS Radiation treatment plans of 30 NPC cases and their pre-treatment 2D-PBD data were analyzed. 3D dose distribution was reconstructed on patient computed tomography (CT) images using the 3DVH software and compared to the treatment plans. Global and organ-specific dose GP (%), and dose-volume histogram (DVH) deviation of each structure was evaluated. Interdependency between GP (%) and the deviation of the volumetric dose was studied through correlation analysis. RESULTS The 3D-MGR achieved global GP (%) similar to conventional 2D-PBD in the same criteria. However, structure-specific GP (%) significantly decreased under stricter criteria, including the planning target volume (PTV). The average deviation of all inspected dose volumes (DV) and volumetric dose (VD) parameters ranged from - 2.93% to 1.17%, with the largest negative deviation in V100% of the PTVnx of - 15.66% and positive deviation in D1cc of the spinal cord of 6.66%. There was no significant correlation between global GP (%) of 2D-PBD or 3D-MGR and the deviation of the most volumetric dosimetry parameters (DV or VD), when the Pearson's coefficient value of 0.8 was used for correlation evaluation. CONCLUSION Even upon passing the pre-treatment phantom based dosimetric QA, there could still be risk of dose error like under-dose in PTVnx and overdose in critical structures. Measurement-guided 3D volumetric dosimetry QA is recommended as the more clinically efficient verification for the complicated NPC IMRT.
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Affiliation(s)
| | | | - Ying-Lin Peng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China
| | - Li Chen
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China
| | - De-Hua Kang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China
| | - Bin Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China
| | - Xiao-Wu Deng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, 510060, People's Republic of China.
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Hirashima H, Nakamura M, Miyabe Y, Uto M, Nakamura K, Mizowaki T. Monitoring of mechanical errors and their dosimetric impact throughout the course of non-coplanar continuous volumetric-modulated arc therapy. Radiat Oncol 2018; 13:27. [PMID: 29444693 PMCID: PMC5813375 DOI: 10.1186/s13014-018-0972-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 02/11/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Volumetric-modulated Dynamic WaveArc therapy (VMDWAT) is a non-coplanar continuous volumetric modulated radiation therapy (VMAT) delivery technique. Here, we monitored mechanical errors and their impact on dose distributions in VMDWAT using logfiles throughout the course of treatment. METHODS Fifteen patients were enrolled (2 skull base tumor patients and 13 prostate cancer patients). VMDWAT plans were created for the enrolled patients. The prescribed dose for the skull base tumor was set as 54 Gy at 1.8 Gy per fraction, and that for the prostate cancer was set as 72 to 78 Gy at 2 Gy per fraction. We acquired logfiles to monitor mechanical errors and their impact on dose distribution in each fraction. The root mean square error (RMSE) in the multi-leaf collimator (MLC), gantry angle, O-ring angle and monitor unit (MU) were calculated using logfiles throughout the course of VMDWAT for each patient. The dosimetric impact of mechanical errors throughout the course of VMDWAT was verified using a logfile-based dose reconstruction method. Dosimetric errors between the reconstructed plans and the original plans were assessed. RESULTS A total of 517 datasets, including 55 datasets for the 2 skull base tumor patients and 462 datasets for the 13 prostate cancer patients, were acquired. The RMSE values were less than 0.1 mm, 0.2°, 0.1°, and 0.4 MU for MLC position, gantry angle, O-ring angle, and MU, respectively. For the skull base tumors, the absolute mean dosimetric errors and two standard deviations throughout the course of treatment were less than 1.4% and 1.1%, respectively. For prostate cancer, these absolute values were less than 0.3% and 0.5%, respectively. The largest dosimetric error of 2.5% was observed in a skull base tumor patient. The resultant dosimetric error in the accumulated daily delivered dose distribution, in the patient with the largest error, was up to 1.6% for all dose-volumetric parameters relative to the planned dose distribution. CONCLUSIONS MLC position, gantry rotation, O-ring rotation and MU were highly accurate and stable throughout the course of treatment. The daily dosimetric errors due to mechanical errors were small. VMDWAT provided high delivery accuracy and stability throughout the course of treatment. TRIAL REGISTRATION UMIN000023870 . Registered: 1 October 2016.
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Affiliation(s)
- Hideaki Hirashima
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Mitsuhiro Nakamura
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan. .,Division of Medical Physics, Department of Information Technology and Medical Engineering, Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - Yuki Miyabe
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Megumi Uto
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Kiyonao Nakamura
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
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Hirashima H, Nakamura M, Miyabe Y, Mukumoto N, Uto M, Nakamura K, Mizowaki T, Hiraoka M. Geometric and dosimetric quality assurance using logfiles and a 3D helical diode detector for Dynamic WaveArc. Phys Med 2017; 43:107-113. [PMID: 29195552 DOI: 10.1016/j.ejmp.2017.10.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/20/2017] [Accepted: 10/26/2017] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To conduct patient-specific geometric and dosimetric quality assurance (QA) for the Dynamic WaveArc (DWA) using logfiles and ArcCHECK (Sun Nuclear Inc., Melbourne, FL, USA). METHODS Twenty DWA plans, 10 for pituitary adenoma and 10 for prostate cancer, were created using RayStation version 4.7 (RaySearch Laboratories, Stockholm, Sweden). Root mean square errors (RMSEs) between the actual and planned values in the logfiles were evaluated. Next, the dose distributions were reconstructed based on the logfiles. The differences between dose-volumetric parameters in the reconstructed plans and those in the original plans were calculated. Finally, dose distributions were assessed using ArcCHECK. In addition, the reconstructed dose distributions were compared with planned ones. RESULTS The means of RMSEs for the gantry, O-ring, MLC position, and MU for all plans were 0.2°, 0.1°, 0.1 mm, and 0.4 MU, respectively. Absolute means of the change in PTV D99% were 0.4 ± 0.4% and 0.1 ± 0.1% points between the original and reconstructed plans for pituitary adenoma and prostate cancer, respectively. The mean of the gamma passing rate (3%/3 mm) between the measured and planned dose distributions was 97.7%. In addition, that between the reconstructed and planned dose distributions was 99.6%. CONCLUSIONS We have demonstrated that the geometric accuracy and gamma passing rates were within AAPM 119 and 142 criteria during DWA. Dose differences in the dose-volumetric parameters using the logfile-based dose reconstruction method were also clinically acceptable in DWA.
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Affiliation(s)
- Hideaki Hirashima
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Mitsuhiro Nakamura
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
| | - Yuki Miyabe
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Nobutaka Mukumoto
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Megumi Uto
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Kiyonao Nakamura
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
| | - Masahiro Hiraoka
- Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan
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Belosi MF, van der Meer R, Garcia de Acilu Laa P, Bolsi A, Weber DC, Lomax AJ. Treatment log files as a tool to identify treatment plan sensitivity to inaccuracies in scanned proton beam delivery. Radiother Oncol 2017; 125:514-519. [PMID: 29054379 DOI: 10.1016/j.radonc.2017.09.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 09/26/2017] [Accepted: 09/27/2017] [Indexed: 10/18/2022]
Abstract
Dose distributions delivered at Gantry 2 at the Paul Scherrer Institut (PSI) can be reconstructed on the patient anatomy based on machine log files. With the present work, the dependency of the log file calculation on the planning optimization technique and on other planning parameters, such as field direction and tumour size, has been investigated. Interestingly, and despite the typically higher modulation of Intensity Modulated Proton Therapy (IMPT) plans, the results for both Single Field Uniform Distribution and IMPT approaches have been found to be similar. In addition, complex fields with steep in-field dose gradients, such as Simultaneous Integrated Boost, and with couch movements in between the delivery, also resulted in good agreement between planned and reconstructed doses. Nevertheless, highly modulated plans can have regions of larger local dose deviations and attention should therefore be paid during the planning stage to the location of isolated, highly weighted pencil beams. We propose also, that further effort should be invested in order to predict field robustness to delivery fluctuations before the clinical delivery of the plan as part of the plan specific Quality Assurance.
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Affiliation(s)
| | | | | | - Alessandra Bolsi
- Centre for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
| | - Damien C Weber
- Centre for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland; Department of Radiation Oncology, University Hospital of Bern, Switzerland; Department of Radiation Oncology, University Hospital of Zürich, Switzerland
| | - Antony J Lomax
- Centre for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland; Department of Physics, Swiss Institute of Technology (ETH), Zürich, Switzerland
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Moignier A, Broggio D, Derreumaux S, Beaudré A, Girinsky T, Paul JF, Drubay D, Lefkopoulos D, Franck D, Aubert B, Deutsch E, Bourhis J. Coronary stenosis risk analysis following Hodgkin lymphoma radiotherapy: A study based on patient specific artery segments dose calculation. Radiother Oncol 2015; 117:467-72. [PMID: 26277431 DOI: 10.1016/j.radonc.2015.07.043] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 06/18/2015] [Accepted: 07/25/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND AND PURPOSE The dose effect-effect relationship for cardiac diseases following radiotherapy suffers from uncertainties. Three dimensional coronary artery (CA) dose calculation after mediastinal Hodgkin lymphoma radiotherapy was performed, using the patient's coronary CT angiography (CCTA), and the relationship between the coronary arteries' radiation doses and the risk of stenosis was estimated. MATERIALS AND METHODS Radiotherapy simulation CT scans and CCTAs of patients treated for a mediastinal Hodgkin lymphoma were used to merge thoracic and detailed cardiovascular anatomies. Radiation treatment parameters were used to estimate CA radiation doses. Twenty-one patients without coronary stenosis (controls) were matched with twelve patients with stenosis (cases). CA segments were considered as sub-volumes of interest. Radiation doses to stenotic segments were compared with those received by normal segments (from cases and controls) using a logistic regression. RESULTS In eleven cases out of twelve, the highest of the coronary dose distribution was on a damaged segment. Logistic regression with CA segments yielded an odds ratio associated with the risk of coronary stenosis of 1.049 per additional gray with the CA segment median dose (95% confidence interval, 1.004-1.095; p-value <0.05). CONCLUSION The CA segment dose significantly increased the risk of stenosis on the segment. Such personalized CA dose calculations on larger cohorts are expected to improve the understanding of the cardiovascular radiation dose-effect relationship.
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Affiliation(s)
- Alexandra Moignier
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SDI/LEDI, France
| | - David Broggio
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SDI/LEDI, France
| | - Sylvie Derreumaux
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SER/UEM, France.
| | - Anne Beaudré
- Institut Gustave Roussy, Service de Radiothérapie Oncologique, France
| | - Théodore Girinsky
- Institut Gustave Roussy, Service de Radiothérapie Oncologique, France
| | | | - Damien Drubay
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SRBE/LEPID, France
| | | | - Didier Franck
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SDI/LEDI, France
| | - Bernard Aubert
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-HOM/SER/UEM, France
| | - Eric Deutsch
- Institut Gustave Roussy, Service de Radiothérapie Oncologique, France
| | - Jean Bourhis
- Institut Gustave Roussy, Service de Radiothérapie Oncologique, France
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Wang ZD, Zhang XQ, Du J, Lu X, Wang Y, Tian R, Liu QJ, Chen Y. Continuous cytogenetic follow-up, over 5 years, of three individuals accidentally irradiated by a cobalt-60 source. Mutat Res Genet Toxicol Environ Mutagen 2015; 779:1-4. [PMID: 25813720 DOI: 10.1016/j.mrgentox.2015.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/26/2015] [Accepted: 01/28/2015] [Indexed: 11/21/2022]
Abstract
A cobalt-60 irradiation accident occurred in Shanxi, China, on April 11, 2008. Five people were exposed to total-body irradiation ranging from 1.7 to 14.5 Gy. Two victims died post-irradiation, due to acute intestinal radiation sickness (at 62 days) and tuberculosis (at 1.5 year). The other three victims received medical follow-ups and were monitored for 5 years with multiple cytogenetic analyses. Unstable chromosome aberrations, including dicentric and centric rings (dic+r) and the micronucleus frequency in binucleated lymphocytes, were monitored. In addition, G-banding karyotype and fluorescence in situ hybridization (FISH) methods were used to analyze translocations, for exploring chromosome stability and for retrospective dosimetry. The results show that unstable chromosome aberrations (dic+r) declined each year, dropping to about 20-40% of initial levels by the 5th year. A similar trend was observed for the micronucleus frequency. Our results show that the translocation frequencies of the three victims, detected by G-banding karyotype, remained stable for the 5 years. Five years after irradiation, the translocation rates of the three victims (G-banding and FISH analyses) were similar. The retrospective estimated doses, reconstructed based on the translocation frequencies, were consistent with the biological doses estimated at the first day post-irradiation using dic+r. The results of this study indicate that chromosome translocation frequencies can be used as a biological dosimeter and are an excellent index for dose reconstruction.
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Poulsen PR, Worm ES, Petersen JBB, Grau C, Fledelius W, Høyer M. Kilovoltage intrafraction motion monitoring and target dose reconstruction for stereotactic volumetric modulated arc therapy of tumors in the liver. Radiother Oncol 2014; 111:424-30. [PMID: 24997991 DOI: 10.1016/j.radonc.2014.05.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 04/30/2014] [Accepted: 05/24/2014] [Indexed: 12/21/2022]
Abstract
PURPOSE To use intrafraction kilovoltage (kV) imaging during liver stereotactic body radiotherapy (SBRT) delivered by volumetric modulated arc therapy (VMAT) to estimate the intra-treatment target motion and to reconstruct the delivered target dose. METHODS Six liver SBRT patients with 2-3 implanted gold markers received SBRT in three fractions of 18.75 Gy or 25 Gy. CTV-to-PTV margins of 5 mm in the axial plane and 10 mm in the cranio-caudal directions were applied. A VMAT plan was designed to give minimum target doses of 95% (CTV) and 67% (PTV). At each fraction, the 3D marker trajectory was estimated by fluoroscopic kV imaging throughout treatment delivery and used to reconstruct the actually delivered CTV dose. The reduction in D95 (minimum dose to 95% of the CTV) relative to the planned D95 was calculated. RESULTS The kV position estimation had mean root-mean-square errors of 0.36 mm and 0.47 mm parallel and perpendicular to the kV imager, respectively. Intrafraction motion caused a mean 3D target position error of 2.9 mm and a mean D95 reduction of 6.0%. The D95 reduction correlated with the mean 3D target position error during a fraction. CONCLUSIONS Kilovoltage imaging for detailed motion monitoring with dose reconstruction of VMAT-based liver SBRT was demonstrated for the first time showing large dosimetric impact of intrafraction tumor motion.
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Affiliation(s)
- Per Rugaard Poulsen
- Department of Oncology, Aarhus University Hospital, Denmark; Institute of Clinical Medicine, Aarhus University, Denmark.
| | - Esben S Worm
- Department of Oncology, Aarhus University Hospital, Denmark; Department of Medical Physics, Aarhus University Hospital, Denmark
| | | | - Cai Grau
- Department of Oncology, Aarhus University Hospital, Denmark; Institute of Clinical Medicine, Aarhus University, Denmark
| | - Walther Fledelius
- Department of Oncology, Aarhus University Hospital, Denmark; Department of Medical Physics, Aarhus University Hospital, Denmark
| | - Morten Høyer
- Department of Oncology, Aarhus University Hospital, Denmark; Institute of Clinical Medicine, Aarhus University, Denmark
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Paluska P, Hanus J, Sefrova J, Rouskova L, Grepl J, Jansa J, Kasaova L, Hodek M, Zouhar M, Vosmik M, Petera J. Utilization of cone-beam CT for offline evaluation of target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment. Rep Pract Oncol Radiother 2012; 17:134-40. [PMID: 24377014 DOI: 10.1016/j.rpor.2012.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 01/11/2012] [Accepted: 03/10/2012] [Indexed: 10/28/2022] Open
Abstract
AIM To assess target volume coverage during prostate image-guided radiotherapy based on bony anatomy alignment and to assess possibility of safety margin reduction. BACKGROUND Implementation of IGRT should influence safety margins. Utilization of cone-beam CT provides current 3D anatomic information directly in irradiation position. Such information enables reconstruction of the actual dose distribution. MATERIALS AND METHODS Seventeen prostate patients were treated with daily bony anatomy image-guidance. Cone-beam CT (CBCT) scans were acquired once a week immediately after bony anatomy alignment. After the prostate, seminal vesicles, rectum and bladder were contoured, the delivered dose distribution was reconstructed. Target dose coverage was evaluated by the proportion of the CTV encompassed by the 95% isodose. Original plans employed a 1 cm safety margin. Alternative plans assuming a smaller 7 mm margin between CTV and PTV were evaluated in the same way. Rectal and bladder volumes were compared with the initial ones. Rectal and bladder volumes irradiated with doses higher than 75 Gy, 70 Gy, 60 Gy, 50 Gy and 40 Gy were analyzed. RESULTS In 12% of reconstructed plans the prostate coverage was not sufficient. The prostate underdosage was observed in 5 patients. Coverage of seminal vesicles was not satisfactory in 3% of plans. Most of the target underdosage corresponded to excessive rectal or bladder filling. Evaluation of alternative plans assuming a smaller 7 mm margin revealed 22% and 11% of plans where prostate and seminal vesicles coverage, respectively, was compromised. These were distributed over 8 and 7 patients, respectively. CONCLUSION Sufficient dose coverage of target volumes was not achieved for all patients. Reducing of safety margin is not acceptable. Initial rectal and bladder volumes cannot be considered representative for subsequent treatment.
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Affiliation(s)
- Petr Paluska
- Department of Medical Biophysics, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Czech Republic ; Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Josef Hanus
- Department of Medical Biophysics, Faculty of Medicine in Hradec Kralove, Charles University in Prague, Czech Republic
| | - Jana Sefrova
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Lucie Rouskova
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Jakub Grepl
- Department of Radiology, University Hospital, Hradec Kralove, Czech Republic
| | - Jan Jansa
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Linda Kasaova
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Miroslav Hodek
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Milan Zouhar
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Milan Vosmik
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
| | - Jiri Petera
- Department of Oncology and Radiotherapy, University Hospital, Hradec Kralove, Czech Republic
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