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Shiraishi S, Yamanaka M, Murai T, Tokuuye K. Evaluation of Delivered Doses in Proton Beam Therapy for Prostate Cancer Using Positron Emission Tomography/Computed Tomography Imaging. Clin Oncol (R Coll Radiol) 2024; 36:265-270. [PMID: 38272762 DOI: 10.1016/j.clon.2024.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/14/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
AIMS Proton beams deposit energy along their paths and stop abruptly without penetrating the opposite side, making it difficult to detect their actual paths. However, confirming the path may lead to evaluating the actual doses to organs at risk in proton therapy for prostate cancer. As proton beams produce positron emitters through nuclear fragmentation reactions, theoretically, proton beam paths can be measured by positron emission tomography/computed tomography (PET/CT). Therefore, this study investigated whether conducting PET/CT examinations immediately after proton beam therapy helps to assess the doses delivered to the rectal and urinary bladder walls, which are the major sites of radiation-related toxicity. MATERIALS AND METHODS Between June 2022 and June 2023, 51 consecutive patients with prostate cancer who underwent proton beam therapy were enrolled and imaged with PET/CT to measure these radioactive particles and validate the actual dose delivered to the rectal and urinary bladder walls. RESULTS The delivered doses assessed using PET/CT after proton beam therapy strongly correlated with the planned volume for proton beam treatment. CONCLUSIONS PET/CT exhibited potential as a valuable tool for validating the irradiated dose to organs at risk.
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Affiliation(s)
- S Shiraishi
- Department of Radiation Oncology, Shonan Kamakura General Hospital, Kamakura City, Kanagawa, Japan; Department of Radiology, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan.
| | - M Yamanaka
- Department of Medical Physics, Shonan Kamakura General Hospital, Kamakura City, Kanagawa, Japan
| | - T Murai
- Department of Radiation Oncology, Shonan Kamakura General Hospital, Kamakura City, Kanagawa, Japan
| | - K Tokuuye
- Department of Radiation Oncology, Shonan Kamakura General Hospital, Kamakura City, Kanagawa, Japan; Department of Radiology, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan
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2
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Cheng HL, Wang JL, Wang XY, Wu XG, Xiao JF, Wang Y, Zheng Y, Jin X, Xu Y, He LJ, Li CB, Li TX, Zheng M, Zhao ZH, He ZY, Li JZ, Li YQ, Hong R. A torus source and its application for non-primary radiation evaluation. Phys Med Biol 2023; 68:245003. [PMID: 37549670 DOI: 10.1088/1361-6560/acede7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 08/07/2023] [Indexed: 08/09/2023]
Abstract
Objective. Non-primary radiation doses to normal tissues from proton therapy may be associated with an increased risk of secondary malignancies, particularly in long-term survivors. Thus, a systematic method to evaluate if the dose level of non-primary radiation meets the IEC standard requirements is needed.Approach. Different from the traditional photon radiation therapy system, proton therapy systems are composed of several subsystems in a thick bunker. These subsystems are all possible sources of non-primary radiation threatening the patient. As a case study, 7 sources in the P-Cure synchrotron-based proton therapy system are modeled in Monte Carlo (MC) code: tandem injector, injection, synchrotron ring, extraction, beam transport line, scanning nozzle and concrete reflection/scattering. To accurately evaluate the synchrotron beam loss and non-primary dose, a new model called the torus source model is developed. Its parametric equations define the position and direction of the off-orbit particle bombardment on the torus pipe shell in the Cartesian coordinate system. Non-primary doses are finally calculated by several FLUKA simulations.Main results. The ratios of summarized non-primary doses from different sources to the planned dose of 2 Gy are all much smaller than the IEC requirements in both the 15-50 cm and 50-200 cm regions. Thus, the P-Cure synchrotron-based proton therapy system is clean and patient-friendly, and there is no need an inner shielding concrete between the accelerator and patient.Significance. Non-primary radiation dose level is a very important indicator to evaluate the quality of a PT system. This manuscript provides a feasible MC procedure for synchrotron-based proton therapy with new beam loss model. Which could help people figure out precisely whether this level complies with the IEC standard before the system put into clinical treatment. What' more, the torus source model could be widely used for bending magnets in gantries and synchrotrons to evaluate non-primary doses or other radiation doses.
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Affiliation(s)
- Han-Long Cheng
- University of Science and Technology of China, National Synchrotron Radiation Laboratory, Hefei 230029, People's Republic of China
- Sino-Israeli Healthy Alliance International Medical Technology Co., Ltd, AcceleratorLaboratory, Weifang 261000, People's Republic of China
| | - Jin-Long Wang
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Xiao-Yun Wang
- Sino-Israeli Healthy Alliance International Medical Technology Co., Ltd, AcceleratorLaboratory, Weifang 261000, People's Republic of China
| | - Xiao-Guang Wu
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Jie-Fang Xiao
- Sino-Israeli Healthy Alliance International Medical Technology Co., Ltd, AcceleratorLaboratory, Weifang 261000, People's Republic of China
| | - Yang Wang
- Sino-Israeli Healthy Alliance International Medical Technology Co., Ltd, AcceleratorLaboratory, Weifang 261000, People's Republic of China
| | - Yun Zheng
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Xiao Jin
- Department of Nuclear Safety, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Ying Xu
- Department of Radiation Source, Nuclear and Radiation Safety Center, Beijing 102401, People's Republic of China
| | - Li-Juan He
- University of Science and Technology of China, National Synchrotron Radiation Laboratory, Hefei 230029, People's Republic of China
| | - Cong-Bo Li
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Tian-Xiao Li
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Min Zheng
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Zi-Hao Zhao
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Zi-Yang He
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Jin-Ze Li
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Yun-Qiu Li
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
| | - Rui Hong
- Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, People's Republic of China
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3
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Caron J, Gonzalez G, Pandey PK, Wang S, Prather K, Ahmad S, Xiang L, Chen Y. Single pulse protoacoustic range verification using a clinical synchrocyclotron. Phys Med Biol 2023; 68:10.1088/1361-6560/acb2ae. [PMID: 36634371 PMCID: PMC10567060 DOI: 10.1088/1361-6560/acb2ae] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/12/2023] [Indexed: 01/14/2023]
Abstract
Objective.Proton therapy as the next generation radiation-based cancer therapy offers dominant advantages over conventional radiation therapy due to the utilization of the Bragg peak; however, range uncertainty in beam delivery substantially mitigates the advantages of proton therapy. This work reports using protoacoustic measurements to determine the location of proton Bragg peak deposition within a water phantom in real time during beam delivery.Approach.In protoacoustics, proton beams have a definitive range, depositing a majority of the dose at the Bragg peak; this dose is then converted to heat. The resulting thermoelastic expansion generates a 3D acoustic wave, which can be detected by acoustic detectors to localize the Bragg peak.Main results.Protoacoustic measurements were performed with a synchrocyclotron proton machine over the exhaustive energy range from 45.5 to 227.15 MeV in clinic. It was found that the amplitude of the acoustic waves is proportional to proton dose deposition, and therefore encodes dosimetric information. With the guidance of protoacoustics, each individual proton beam (7 pC/pulse) can be directly visualized with sub-millimeter (<0.7 mm) resolution using single beam pulse for the first time.Significance.The ability to localize the Bragg peak in real-time and obtain acoustic signals proportional to dose within tumors could enable precision proton therapy and hope to progress towardsin vivomeasurements.
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Affiliation(s)
- Joseph Caron
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, United States of America
| | - Gilberto Gonzalez
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, United States of America
| | - Prabodh Kumar Pandey
- Department of Radiological Sciences, University of California at Irvine, Irvine, CA 92697, United States of America
| | - Siqi Wang
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
| | - Kiana Prather
- University of Oklahoma College of Medicine, Oklahoma City, OK, 73104, United States of America
| | - Salahuddin Ahmad
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, United States of America
| | - Liangzhong Xiang
- Department of Radiological Sciences, University of California at Irvine, Irvine, CA 92697, United States of America
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
- Beckman Laser Institute & Medical Clinic, University of California, Irvine, Irvine, CA 92612, United States of America
| | - Yong Chen
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, United States of America
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4
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Bauer J, Hildebrandt M, Baumgartl M, Fiedler F, Robert C, Buvat I, Enghardt W, Parodi K. Quantitative assessment of radionuclide production yields in in-beam and offline PET measurements at different proton irradiation facilities. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac7a89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/20/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. Reliable radionuclide production yield data are a prerequisite for positron-emission-tomography (PET) based in vivo proton treatment verification. In this context, activation data acquired at two different treatment facilities with different imaging systems were analyzed to provide experimentally determined radionuclide yields in thick targets and were compared with each other to investigate the impact of the respective imaging technique. Approach. Homogeneous thick targets (PMMA, gelatine, and graphite) were irradiated with mono-energetic proton pencil-beams at two distinct energies. Material activation was measured (i) in-beam during and after beam delivery with a double-head prototype PET camera and (ii) offline shortly after beam delivery with a commercial full-ring PET/CT scanner. Integral as well as depth-resolved β
+-emitter yields were determined for the dominant positron-emitting radionuclides 11C, 15O, 13N and (in-beam only) 10C. In-beam data were used to investigate the qualitative impact of different monitoring time schemes on activity depth profiles and their quantitative impact on count rates and total activity. Main results. Production yields measured with the in-beam camera were comparable to or higher compared to respective offline results. Depth profiles of radionuclide-specific yields obtained from the double-head camera showed qualitative differences to data acquired with the full-ring camera with a more convex profile shape. Considerable impact of the imaging timing scheme on the activity profile was observed for gelatine only with a range variation of up to 3.5 mm. Evaluation of the coincidence rate and the total number of observed events in the considered workflows confirmed a strongly decreasing rate in targets with a large oxygen fraction. Significance. The observed quantitative and qualitative differences between the datasets underline the importance of a thorough system commissioning. Due to the lack of reliable cross-section data, in-house phantom measurements are still considered a gold standard for careful characterization of the system response and to ensure a reliable beam range verification.
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Nemallapudi MV, Rahman A, Chen AEF, Lee SC, Lin CH, Chu ML, Chou CY. Positron Emitter Depth Distribution in PMMA Irradiated With 130-MeV Protons Measured Using TOF-PET Detectors. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2022. [DOI: 10.1109/trpms.2021.3084953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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6
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Poon DMC, Wu S, Ho L, Cheung KY, Yu B. Proton Therapy for Prostate Cancer: Challenges and Opportunities. Cancers (Basel) 2022; 14:cancers14040925. [PMID: 35205673 PMCID: PMC8870339 DOI: 10.3390/cancers14040925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 01/02/2023] Open
Abstract
Simple Summary Reported clinical outcomes of proton therapy (PT) for localized prostate cancer are similar to photon-based external beam radiotherapy. Apparently, the dosimetric advantages of PT have yet to be translated to clinical benefits. The suboptimal clinical outcomes of PT might be attributable to inadequate dose prescription, as indicated by the ASCENDE-RT trial. Moreover, uncertainties involved in the treatment planning and delivery processes, as well as technological limitations in PT treatment systems, may lead to discrepancies between planned doses and actual doses delivered to patients. In this article, we reviewed the current status of PT for prostate cancer and discussed different clinical implementations that could potentially improve the clinical outcome of PT for prostate cancer. Various technological advancements under which uncertainties in dose calculations can be minimized, including MRI-guided PT, dual-energy photon-counting CT and high-resolution Monte Carlo-based treatment planning systems, are highlighted. Abstract The dosimetric advantages of proton therapy (PT) treatment plans are demonstrably superior to photon-based external beam radiotherapy (EBRT) for localized prostate cancer, but the reported clinical outcomes are similar. This may be due to inadequate dose prescription, especially in high-risk disease, as indicated by the ASCENDE-RT trial. Alternatively, the lack of clinical benefits with PT may be attributable to improper dose delivery, mainly due to geometric and dosimetric uncertainties during treatment planning, as well as delivery procedures that compromise the dose conformity of treatments. Advanced high-precision PT technologies, and treatment planning and beam delivery techniques are being developed to address these uncertainties. For instance, external magnetic resonance imaging (MRI)-guided patient setup rooms are being developed to improve the accuracy of patient positioning for treatment. In-room MRI-guided patient positioning systems are also being investigated to improve the geometric accuracy of PT. Soon, high-dose rate beam delivery systems will shorten beam delivery time to within one breath hold, minimizing the effects of organ motion and patient movements. Dual-energy photon-counting computed tomography and high-resolution Monte Carlo-based treatment planning systems are available to minimize uncertainties in dose planning calculations. Advanced in-room treatment verification tools such as prompt gamma detector systems will be used to verify the depth of PT. Clinical implementation of these new technologies is expected to improve the accuracy and dose conformity of PT in the treatment of localized prostate cancers, and lead to better clinical outcomes. Improvement in dose conformity may also facilitate dose escalation, improving local control and implementation of hypofractionation treatment schemes to improve patient throughput and make PT more cost effective.
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Affiliation(s)
- Darren M. C. Poon
- Comprehensive Oncology Centre, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China;
| | - Stephen Wu
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
- Correspondence: ; Tel.: +852-29171413
| | - Leon Ho
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
| | - Kin Yin Cheung
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
| | - Ben Yu
- Medical Physics Department, Hong Kong Sanatorium & Hospital, Hong Kong 999077, China; (L.H.); (K.Y.C.); (B.Y.)
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7
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Zhang F, Zhang J, Lu Y, Sheng Y, Sun Y, Zhang J, Cheng J, Zhou R. Radioactivity and Space Range of Ultra-Low-Activity for in vivo Off-line PET Verification of Proton and Carbon Ion Beam-A Phantom Study. Front Public Health 2021; 9:771017. [PMID: 34938708 PMCID: PMC8687193 DOI: 10.3389/fpubh.2021.771017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 11/03/2021] [Indexed: 11/19/2022] Open
Abstract
Purpose: The radioactivity induced by proton and heavy ion beam belongs to the ultra-low-activity (ULA). Therefore, the radioactivity and space range of commercial off-line positron emission tomography (PET) acquisition based on ULA should be evaluated accurately to guarantee the reliability of clinical verification. The purpose of this study is to quantify the radioactivity and space range of off-line PET acquisition by simulating the ULA triggered by proton and heavy ion beam. Methods: PET equipment validation phantom and low activity 18F-FDG were used to simulate the ULA with radioactivity of 11.1–1480 Bq/mL. The radioactivity of ULA was evaluated by comparing the radioactivity in the images with the values calculated from the decay function with a radioactivity error tolerance of 5%. The space range of ULA was evaluated by comparing the width of the R50 analyzed activity distribution curve with the actual width of the container with a space range error tolerance of 4 mm. Results: When radioactivity of ULA was >148 Bq/mL, the radioactivity error was <5%. When radioactivity of ULA was >30 Bq/mL, the space range error was below 4 mm. Conclusions: Off-line PET can be used to quantify the radioactivity of proton and heavy ion beam when the ULA exceeds 148 Bq/mL, both in radioactivity and in space range.
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Affiliation(s)
- Fuquan Zhang
- College of Physics, Sichuan University, Chengdu, China.,Shanghai Key Laboratory of Radiation Oncology, Shanghai, China.,Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China.,Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China
| | - Junyu Zhang
- College of Physics, Sichuan University, Chengdu, China.,Shanghai Key Laboratory of Radiation Oncology, Shanghai, China.,Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China.,Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China
| | - Yan Lu
- Department of Radiotherapy, Shanghai Proton and Heavy Ion Center (SPHIC), Shanghai, China
| | - Yixiangzi Sheng
- Department of Radiotherapy, Shanghai Proton and Heavy Ion Center (SPHIC), Shanghai, China
| | - Yun Sun
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China
| | - Jiangang Zhang
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China
| | - Jingyi Cheng
- Shanghai Key Laboratory of Radiation Oncology, Shanghai, China.,Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China.,Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China
| | - Rong Zhou
- College of Physics, Sichuan University, Chengdu, China
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8
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Krishnamoorthy S, Teo BKK, Zou W, McDonough J, Karp JS, Surti S. A proof-of-concept study of an in-situ partial-ring time-of-flight PET scanner for proton beam verification. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2021; 5:694-702. [PMID: 34746539 DOI: 10.1109/trpms.2020.3044326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Development of a PET system capable of in-situ imaging requires a design that can accommodate the proton treatment beam nozzle. Among the several PET instrumentation approaches developed thus far, the dual-panel PET scanner is often used as it is simpler to develop and integrate within the proton therapy gantry. Partial-angle coverage of these systems can however lead to limited-angle artefacts in the reconstructed PET image. We have previously demonstrated via simulations that time-of-flight (TOF) reconstruction reduces the artifacts accompanying limited-angle data, and permits proton range measurement with 1-2 mm accuracy and precision. In this work we show measured results from a small proof-of-concept dual-panel PET system that uses TOF information to reconstruct PET data acquired after proton irradiation. The PET scanner comprises of two detector modules, each comprised of an array of 4×4×30 mm3 lanthanum bromide scintillator. Measurements are performed with an oxygen-rich gel-water, an adipose tissue equivalent material, and in vitro tissue phantoms. For each phantom measurement, 2 Gy dose was deposited using 54 - 100 MeV proton beams. For each phantom, a Monte Carlo simulation generating the expected distribution of PET isotope from the corresponding proton irradiation was also performed. Proton range was calculated by drawing multiple depth-profiles over a central region encompassing the proton dose deposition. For each profile, proton range was calculated using two techniques (a) 50% pick-off from the distal edge of the profile, and (b) comparing the measured and Monte Carlo profile to minimize the absolute sum of differences over the entire profile. A 10 min PET acquisition acquired with minimal delay post proton-irradiation is compared with a 10 min PET scan acquired after a 20 min delay. Measurements show that PET acquisition with minimal delay is necessary to collect 15O signal, and maximize 11C signal collection with a short PET acquisition. In comparison with the 50% pick-off technique, the shift technique is more robust and offers better precision in measuring the proton range for the different phantoms. Range measurements from PET images acquired with minimal delay, and the shift technique demonstrate the ability to achieve <1.5 mm accuracy and precision in estimating proton range.
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Affiliation(s)
| | - Boon-Keng K Teo
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - James McDonough
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Joel S Karp
- Departments of Radiology and Physics & Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Suleman Surti
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 USA
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9
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España S, Sánchez-Parcerisa D, Ibáñez P, Sánchez-Tembleque V, Udías JM, Onecha VV, Gutierrez-Uzquiza A, Bäcker CM, Bäumer C, Herrmann K, Fragoso Costa P, Timmermann B, Fraile LM. Direct proton range verification using oxygen-18 enriched water as a contrast agent. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Zhong Y, Lu W, Chen M, Xiong Z, Cheng X, Hu K, Shao Y. Novel On-line PET Imaging for Intra-Beam Range Verification and Delivery Optimization: A Simulation Feasibility Study. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2021; 4:212-217. [PMID: 33778233 DOI: 10.1109/trpms.2019.2950231] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
On-line PET image-based method uses an initial particle beam to measure the particle beam range (BR) within the same fraction so that any measured range-shift with respect to the predicted BR can be compensated before the rest therapeutic beam deliveries. However, the method requires to use a low-dose initial beam to minimize the risk of beam overshooting, which leads to low image count and inaccurate BR measurement. In this in-silico study, we evaluated the feasibility of a new on-line PET imaging method that measures BR at the mid-plane of a target volume with part of the high-dose therapy beams to verify BR and guide adaptive treatment re-planning. Simulations included various processes of proton beam radiations to a tumor inside a human brain phantom, positron and PET image generation at the mid-plane with initial beams, activity range measurement, and range-shift compensated beam delivery. The results demonstrated that the new method, under the simulated conditions, can achieve ~1.1 mm mid-plane BR measurement accuracy and closely match the delivered range-shift compensated dose distribution with the planned one. Overall, it is promising that this new method may significantly improve particle therapy accuracy.
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Affiliation(s)
- Yuncheng Zhong
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Weiguo Lu
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Mingli Chen
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Zhenyu Xiong
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Xinyi Cheng
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Kun Hu
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
| | - Yiping Shao
- Division of Medical Physics and Engineering Department of Radiation Oncology University of Texas Southwestern Medical Center Dallas, Texas 75390 USA
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11
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Sun L, Hu W, Lai S, Shi L, Chen J. In Vivo 3-D Dose Verification Using PET/CT Images After Carbon-Ion Radiation Therapy. Front Oncol 2021; 11:621394. [PMID: 33791210 PMCID: PMC8006088 DOI: 10.3389/fonc.2021.621394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 01/26/2021] [Indexed: 11/29/2022] Open
Abstract
Objective To investigate the usefulness of positron emission tomography (PET) images obtained after carbon-ion irradiation for dose verification in carbon-ion radiotherapy. Methods and Materials An anthropomorphic head phantom was used in this study. Three cubes with volumes of 1, 4, and 10 ml were contoured as targets in the phantom CT through a treatment planning system. Treatment plans with six prescriptions from 2.5 to 10 Gy (2.5, 3, 5, 6, 8, and 10 Gy effective dose) were designed and delivered by 90° fixed carbon-ion beams, respectively. After irradiation of the phantom, a PET/CT scan was performed to fuse the treatment-planning CT image with the PET/CT image. The relationship between target volume and the standard uptake value (SUV) in PET/CT was evaluated for corresponding plan prescription. The MIM Maestro software was used for the image fusion and data analysis. Results SUV in the target had an approximate linear relationship with the effective dose. The same effective dose could generate a roughly equal SUV for different target volumes (p < 0.05). Conclusions It is feasible to verify the actual 3-D dose distribution of carbon-ion radiotherapy by the approach in this study.
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Affiliation(s)
- Lining Sun
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Weigang Hu
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Songtao Lai
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Leijun Shi
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Junchao Chen
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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12
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Sano A, Nishio T, Masuda T, Karasawa K. Denoising PET images for proton therapy using a residual U-net. Biomed Phys Eng Express 2021; 7. [PMID: 33540390 DOI: 10.1088/2057-1976/abe33c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 02/04/2021] [Indexed: 11/11/2022]
Abstract
The use of proton therapy has the advantage of high dose concentration as it is possible to concentrate the dose on the tumor while suppressing damage to the surrounding normal organs. However, the range uncertainty significantly affects the actual dose distribution in the vicinity of the proton range, limiting the benefit of proton therapy for reducing the dose to normal organs. By measuring the annihilation gamma rays from the produced positron emitters, it is possible to obtain a proton induced positron emission tomography (pPET) image according to the irradiation region of the proton beam. Smoothing with a Gaussian filter is generally used to denoise PET images; however, this approach lowers the spatial resolution. Furthermore, other conventional smoothing processing methods may deteriorate the steep region of the pPET images. In this study, we proposed a denoising method based on a Residual U-Net for pPET images. We conducted the Monte Carlo simulation and irradiation experiment on a human phantom to obtain pPET data. The accuracy of the range estimation and the image similarity were evaluated for pPET images using the Residual U-Net, a Gaussian filter, a median filter, the block-matching and 3D-filtering (BM3D), and a total variation (TV) filter. Usage of the Residual U-Net yielded effective results corresponding to the range estimation; however, the results of peak-signal-to-noise ratio were identical to those for the Gaussian filter, median filter, BM3D, and TV filter. The proposed method can contribute to improving the accuracy of treatment verification and shortening the PET measurement time.
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Affiliation(s)
- Akira Sano
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women's Medical University, 8-1, Kawadacho, Shinjuku-ku, Shinjuku-ku, Tokyo, 162-8666, JAPAN
| | - Teiji Nishio
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women's Medical University, 8-1, Kawadacho, Shinjuku-ku, Shinjuku-ku, Tokyo, 162-8666, JAPAN
| | - Takamitsu Masuda
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women's Medical University, 8-1, Kawadacho, Shinjuku-ku, Shinjuku-ku, Tokyo, 162-8666, JAPAN
| | - Kumiko Karasawa
- Department of Radiation Oncology, School of Medicine, Tokyo Women's Medical University, 8-1, Kawadacho, Shinjuku-ku, Shinjuku-ku, Tokyo, 162-8666, JAPAN
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13
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Fjæra LF, Indelicato DJ, Ytre-Hauge KS, Muren LP, Lassen-Ramshad Y, Toussaint L, Dahl O, Stokkevåg CH. Spatial Agreement of Brainstem Dose Distributions Depending on Biological Model in Proton Therapy for Pediatric Brain Tumors. Adv Radiat Oncol 2021; 6:100551. [PMID: 33490724 PMCID: PMC7811129 DOI: 10.1016/j.adro.2020.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/13/2020] [Accepted: 08/20/2020] [Indexed: 11/02/2022] Open
Abstract
Purpose During radiation therapy for pediatric brain tumors, the brainstem is a critical organ at risk, possibly with different radio-sensitivity across its substructures. In proton therapy, treatment planning is currently performed using a constant relative biological effectiveness (RBE) of 1.1 (RBE1.1), whereas preclinical studies point toward spatial variability of this factor. To shed light on this biological uncertainty, we investigated the spatial agreement between isodose maps produced by different RBE models, with emphasis on (smaller) substructures of the brainstem. Methods and Materials Proton plans were recalculated using Monte Carlo simulations in 3 anonymized pediatric patients with brain tumors (a craniopharyngioma, a low-grade glioma, and a posterior fossa ependymoma) to obtain dose and linear energy transfer distributions. Doses and volume metrics for the brainstem and its substructures were calculated using a constant RBE1.1, 4 phenomenological RBE models with varying (α/β)x parameters, and with a simpler linear energy transfer-dependent model. The spatial agreement between the dose distributions of constant RBE1.1 versus the variable RBE models was compared using the Dice similarity coefficient. Results The spatial agreement between the variable RBE dose distributions and RBE1.1 decreased with increasing isodose levels in all patient cases. The patient with ependymoma showed the greatest variation in dose and dose volumes, where V50Gy(RBE) in the brainstem increased from 32% (RBE1.1) to 35% to 49% depending on the applied model, corresponding to a spatial agreement (Dice similarity coefficient) between 0.79 and 0.95. The remaining patients showed similar trends, however, with lower absolute values due to lower brainstem doses. Conclusions All phenomenological RBE models fully enclosed the isodose volumes of the constant RBE1.1, and the volumes based on variable RBE spatially agreed. The spatial agreement was dependent on the isodose level, where higher isodose levels showed larger expansions and less agreement between the variable RBE models and RBE1.1.
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Affiliation(s)
| | - Daniel J Indelicato
- Department of Radiation Oncology, University of Florida, Jacksonville, Florida
| | | | - Ludvig P Muren
- Department of Medical Physics, Aarhus University/Aarhus University Hospital, Denmark
| | | | - Laura Toussaint
- Department of Medical Physics, Aarhus University/Aarhus University Hospital, Denmark
| | - Olav Dahl
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
| | - Camilla H Stokkevåg
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
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14
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Ozoemelam I, van der Graaf E, van Goethem MJ, Kapusta M, Zhang N, Brandenburg S, Dendooven P. Feasibility of quasi-prompt PET-based range verification in proton therapy. Phys Med Biol 2020; 65:245013. [PMID: 32650323 DOI: 10.1088/1361-6560/aba504] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Compared to photon therapy, proton therapy allows a better conformation of the dose to the tumor volume with reduced radiation dose to co-irradiated tissues. In vivo verification techniques including positron emission tomography (PET) have been proposed as quality assurance tools to mitigate proton range uncertainties. Detection of differences between planned and actual dose delivery on a short timescale provides a fast trigger for corrective actions. Conventional PET-based imaging of 15O (T1/2 = 2 min) and 11C (T1/2 = 20 min) distributions precludes such immediate feedback. We here present a demonstration of near real-time range verification by means of PET imaging of 12N (T1/2 = 11 ms). PMMA and graphite targets were irradiated with a 150 MeV proton pencil beam consisting of a series of pulses of 10 ms beam-on and 90 ms beam-off. Two modules of a modified Siemens Biograph mCT PET scanner (21 × 21 cm2 each), installed 25 cm apart, were used to image the beam-induced PET activity during the beam-off periods. The modifications enable the detectors to be switched off during the beam-on periods. 12N images were reconstructed using planar tomography. Using a 1D projection of the 2D reconstructed 12N image, the activity range was obtained from a fit of the activity profile with a sigmoid function. Range shifts due to modified target configurations were assessed for multiples of the clinically relevant 108 protons per pulse (approximately equal to the highest intensity spots in the pencil beam scanning delivery of a dose of 1 Gy over a cubic 1 l volume). The standard deviation of the activity range, determined from 30 datasets obtained from three irradiations on PMMA and graphite targets, was found to be 2.5 and 2.6 mm (1σ) with 108 protons per pulse and 0.9 and 0.8 mm (1σ) with 109 protons per pulse. Analytical extrapolation of the results from this study shows that using a scanner with a solid angle coverage of 57%, with optimized detector switching and spot delivery times much smaller than the 12N half-life, an activity range measurement precision of 2.0 mm (1σ) and 1.3 mm (1σ) within 50 ms into an irradiation with 4 × 107 and 108 protons per pencil beam spot can be potentially realized. Aggregated imaging of neighboring spots or, if possible, increasing the number of protons for a few probe beam spots will enable the realization of higher precision range measurement.
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Affiliation(s)
- Ikechi Ozoemelam
- KVI-Center for Advanced Radiation Technology, University of Groningen, The Netherlands
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15
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Fjæra LF, Indelicato DJ, Stokkevåg CH, Muren LP, Hsi WC, Ytre-Hauge KS. Implementation of a double scattering nozzle for Monte Carlo recalculation of proton plans with variable relative biological effectiveness. Phys Med Biol 2020; 65. [PMID: 33053524 DOI: 10.1088/1361-6560/abc12d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/14/2020] [Indexed: 11/12/2022]
Abstract
A constant relative biological effectiveness (RBE) of 1.1 is currently used in clinical proton therapy. However, theRBEvaries with factors such as dose level, linear energy transfer (LET) and tissue type. MultipleRBEmodels have been developed to account for this biological variation. To enable recalculation of patients treated with double scattering (DS) proton therapy, includingLETand variableRBE, we implemented and commissioned a Monte Carlo (MC) model of a DS treatment nozzle. The main components from the IBA nozzle were implemented in the FLUKA MC code. We calibrated and verified the following entities to experimental measurements: range of pristine Bragg peaks (PBPs) and spread-out Bragg peaks (SOBPs), energy spread, lateral profiles, compensator range degradation, and absolute dose. We recalculated two patients with different field setups, comparing FLUKA vs. treatment planning system (TPS) dose, also obtainingLETand variableRBEdoses. We achieved good agreement between FLUKA and measurements. The range differences between FLUKA and measurements were for the PBPs within ±0.9 mm (83% ⩽ 0.5 mm), and for SOBPs ±1.6 mm (82% ⩽ 0.5 mm). The differences in modulation widths were below 5 mm (79% ⩽ 2 mm). The differences in the distal dose fall off (D80%-D20%) were below 0.5 mm for all PBPs and the lateral penumbras diverged from measurements by less than 1 mm. The mean dose difference (RBE= 1.1) in the target between the TPS and FLUKA were below 0.4% in a three-field plan and below 1.4% in a four-field plan. A dose increase of 9.9% and 7.2% occurred when using variableRBEfor the two patients, respectively. We presented a method to recalculate DS proton plans in the FLUKA MC code. The implementation was used to obtainLETand variableRBEdose and can be used for investigating variableRBEfor previously treated patients.
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Affiliation(s)
- Lars Fredrik Fjæra
- Department of Physics and Technology, University of Bergen, Bergen, Norway
| | - Daniel J Indelicato
- Department of Radiation Oncology, University of Florida, Jacksonville, FL, United States of America
| | - Camilla H Stokkevåg
- Department of Physics and Technology, University of Bergen, Bergen, Norway.,Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
| | - Ludvig P Muren
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
| | - Wen C Hsi
- Department of Radiation Oncology, University of Florida, Jacksonville, FL, United States of America
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16
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Grevillot L, Boersma DJ, Fuchs H, Aitkenhead A, Elia A, Bolsa M, Winterhalter C, Vidal M, Jan S, Pietrzyk U, Maigne L, Sarrut D. Technical Note: GATE‐RTion: a GATE/Geant4 release for clinical applications in scanned ion beam therapy. Med Phys 2020; 47:3675-3681. [DOI: 10.1002/mp.14242] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/15/2020] [Accepted: 05/03/2020] [Indexed: 11/09/2022] Open
Affiliation(s)
- L. Grevillot
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - D. J. Boersma
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
- ACMIT Gmbh Viktor‐Kaplan‐Straße 2/1A‐2700Wiener Neustadt Austria
| | - H Fuchs
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
- Medical University of Vienna Vienna Austria
- Department of Radiation Therapy Medical University of Vienna/AKH Vienna Vienna Austria
| | - A. Aitkenhead
- Division of Cancer Sciences University of ManchesterManchester Cancer Research CentreThe Christie NHS Foundation Trust Manchester UK
| | - A. Elia
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - M. Bolsa
- MedAustron Ion Therapy Center Marie Curie‐Straße 5A‐2700Wiener Neustadt Austria
| | - C. Winterhalter
- Division of Cancer Sciences University of ManchesterThe Christie NHS Foundation Trust Manchester UK
| | - M. Vidal
- Centre Antoine LACASSAGNE Université Côte d’Azur – Fédération Claude Lalanne Nice France
| | - S. Jan
- UMR BioMaps CEACNRSInsermUniversité Paris‐Saclay 4 place du Général Leclerc91401Orsay France
| | | | - L. Maigne
- Université Clermont AuvergneCNRS/IN2P3Laboratoire de Physique de Clermont, UMR6533 4 avenue Blaise Pascal TSA 60026 CS60026 63178Aubière cedex France
| | - D. Sarrut
- Université de LyonCREATISCNRS UMR5220Inserm U1044INSA‐LyonUniversité Lyon 1 Lyon France
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17
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Durante M, Flanz J. Charged particle beams to cure cancer: Strengths and challenges. Semin Oncol 2019; 46:219-225. [DOI: 10.1053/j.seminoncol.2019.07.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 07/23/2019] [Indexed: 12/28/2022]
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18
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Kostara E, Sportelli G, Belcari N, Camarlinghi N, Cerello P, Del Guerra A, Ferrero V, Fiorina E, Giraudo G, Morrocchi M, Pennazio F, Pullia M, Rivetti A, Rolo MD, Rosso V, Wheadon R, Bisogni MG. Particle beam microstructure reconstruction and coincidence discrimination in PET monitoring for hadron therapy. Phys Med Biol 2019; 64:035001. [PMID: 30572320 DOI: 10.1088/1361-6560/aafa28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Positron emission tomography is one of the most mature techniques for monitoring the particles range in hadron therapy, aiming to reduce treatment uncertainties and therefore the extent of safety margins in the treatment plan. In-beam PET monitoring has been already performed using inter-spill and post-irradiation data, i.e. while the particle beam is off or paused. The full beam acquisition procedure is commonly discarded because the particle spills abruptly increase the random coincidence rates and therefore the image noise. This is because random coincidences cannot be separated by annihilation photons originating from radioactive decays and cannot be corrected with standard random coincidence techniques due to the time correlation of the beam-induced background with the ion beam microstructure. The aim of this paper is to provide a new method to recover in-spill data to improve the images obtained with full-beam PET acquisitions. This is done by estimating the temporal microstructure of the beam and thus selecting input PET events that are less likely to be random ones. The PET detector we used was the one developed within the INSIDE project and tested at the CNAO synchrotron-based facility. The data were taken on a PMMA phantom irradiated with 72 MeV proton pencil beams. The obtained results confirm the possibility of improving the acquired PET data without any external signal coming from the synchrotron or ad hoc detectors.
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Affiliation(s)
- E Kostara
- Istituto Nazionale di Fisica Nucleare (INFN), Pisa, Italy. Department of Physical Sciences, Earth and Environment, University of Siena, Siena, Italy
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19
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Zhang J, Lu Y, Hsi W, Zhang J, Sheng Y, Shi L, Wang W, Lu J, Zhou R, Cheng J. Evaluation of Proton Therapy Accuracy Using a PMMA Phantom and PET Prediction Module. Front Oncol 2018; 8:523. [PMID: 30483477 PMCID: PMC6243057 DOI: 10.3389/fonc.2018.00523] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/24/2018] [Indexed: 11/13/2022] Open
Abstract
Purpose: Positron emission tomography (PET) scanning is a widely used method of proton therapy verification. In this study, a proton radiotherapy accuracy verification process was developed by comparing predicted and measured PET data to verify the correctness of PET prediction and was tested at the Shanghai Proton and Heavy Ion Center. Method: Irradiation was performed on a polymethyl methacrylate (PMMA) phantom. There were two dose groups, to which 2 and 4 Gy doses were delivered, and each dose group had different designed dose depths ranging from 5 to 20 cm. The predicted PET results were obtained using a PET prediction calculation module. The measured data were collected with a PET/computed tomography device. The predicted and measured PET data were normalized to similar PET amplitude values before comparison and were compared using depth and lateral profiles for the position error. The error was evaluated at the position corresponding to 50% of the maximum on the PET curves. The mean and standard deviation were calculated based on the data sampled in the scoring area. Gamma index analysis is also applied in the comparison. Results: In the depth comparison, the 2 and 4 Gy dose cases yielded similar mean depth errors between 1 and −1 mm, and the deviation was <2 mm. In the lateral comparison, the 2 Gy cases had a mean lateral error around 1 mm, and the 4 Gy cases had a mean lateral error <1 mm, with a standard deviation <1 mm for both the 2 and 4 Gy cases. All the cases have a gamma passing rate over 95%. Conclusion: The comparison of these PMMA phantom cases revealed good agreement between the predicted and measured PET data, with depth and lateral position errors <2 mm in total, considering the uncertainty. The comparison results demonstrate that the PET predictions obtained in PMMA phantom tests for single proton beam therapy verification are reliable and that the research can be extended to verification in human body treatment with further investigation.
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Affiliation(s)
- Junyu Zhang
- College of Physical Science and Technology (College of Nuclear Science and Engineering), Sichuan University, Chengdu, China.,Key Laboratory of Radiation Physics and Technology Ministry of Education, Chengdu, China
| | - Yan Lu
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Wenchien Hsi
- Department of Radiation Oncology, Miami Cancer Institute Baptist Health South Florida, Miami, FL, United States
| | - Jiangang Zhang
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Yinxiangzi Sheng
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Leijun Shi
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Weiwei Wang
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Jiade Lu
- Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Rong Zhou
- College of Physical Science and Technology (College of Nuclear Science and Engineering), Sichuan University, Chengdu, China.,Key Laboratory of Radiation Physics and Technology Ministry of Education, Chengdu, China
| | - Jingyi Cheng
- Department of Nuclear Medicine, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai, China
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20
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Hillbrand M, Landry G, Ebert S, Dedes G, Pappas E, Kalaitzakis G, Kurz C, Würl M, Englbrecht F, Dietrich O, Makris D, Pappas E, Parodi K. Gel dosimetry for three dimensional proton range measurements in anthropomorphic geometries. Z Med Phys 2018; 29:162-172. [PMID: 30249351 DOI: 10.1016/j.zemedi.2018.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/14/2018] [Accepted: 08/26/2018] [Indexed: 11/27/2022]
Abstract
Proton beams used for radiotherapy have potential for superior sparing of normal tissue, although range uncertainties are among the main limiting factors in the accuracy of dose delivery. The aim of this study was to benchmark an N-vinylpyrrolidone based polymer gel to perform three-dimensional measurement of geometric proton beam characteristics and especially to test its suitability as a range probe in combination with an anthropomorphic phantom. For single proton pencil beams as well as for 3×3cm2 mono-energy layers depth dose profiles, lateral dose distribution at different depths and proton range were evaluated in simple cubic gel phantoms at different energies from 75 to 115MeV and different dose levels. In addition, a 90MeV mono-energetic beam was delivered to an anthropomorphic 3D printed head phantom, which was filled with gel. Subsequently, all phantoms underwent magnetic resonance imaging using an axial pixel size of 0.68-0.98mm and with slice thicknesses of 2 or 3mm to derive a 3-dimensional distribution of the T2 relaxation time, which correlates with radiation dose. Indices describing lateral dose distribution and proton range were compared against predictions from a treatment planning system (TPS, for cubic and head phantoms) and Monte Carlo simulations (MC, for the head phantom) after manual rigid co-registration with the T2 relaxation time datasets. For all pencil beams, the FWHM agreement with TPS was better than 1mm or 7%. For the mono-energetic layer, the agreement with TPS in this respect was even better than 0.3mm in each case. With respect to range, results from gel measurements differed no more than 0.9mm (1.6%) from values predicted by TPS. In case of the anthropomorphic phantom, deviations with respect to a nominal range of about 61mm as well as in FWHM were slightly higher, namely within 1.0mm and 1.1mm respectively. Average deviations between gel and TPS/MC were similar (-0.3mm±0.4mm/-0.2±0.5mm). In conclusion, polymer gel dosimetry was found to be a valuable tool to determine geometric proton beam properties three-dimensionally and with high spatial resolution in simple cubic as well as in a more complex anthropomorphic phantom. Post registration range errors of the order of 1mm could be achieved. The additional registration uncertainty (95%) was 1mm.
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Affiliation(s)
| | - Guillaume Landry
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - Sandy Ebert
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - George Dedes
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - Eleftherios Pappas
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, Greece
| | | | - Christopher Kurz
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - Matthias Würl
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - Franz Englbrecht
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany
| | - Olaf Dietrich
- Department of Radiology, University Hospital, LMU Munich, Munich, Germany
| | - Dimitris Makris
- Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, Greece
| | - Evangelos Pappas
- Radiology & Radiotherapy Sector, Department of Biomedical Sciences, University of West Attica, Athens, Greece
| | - Katia Parodi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany.
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21
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Pennazio F, Battistoni G, Bisogni MG, Camarlinghi N, Ferrari A, Ferrero V, Fiorina E, Morrocchi M, Sala P, Sportelli G, Wheadon R, Cerello P. Carbon ions beam therapy monitoring with the INSIDE in-beam PET. Phys Med Biol 2018; 63:145018. [PMID: 29873299 DOI: 10.1088/1361-6560/aacab8] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In vivo range monitoring techniques are necessary in order to fully take advantage of the high dose gradients deliverable in hadrontherapy treatments. Positron emission tomography (PET) scanners can be used to monitor beam-induced activation in tissues and hence measure the range. The INSIDE (Innovative Solutions for In-beam DosimEtry in Hadrontherapy) in-beam PET scanner, installed at the Italian National Center of Oncological Hadrontherapy (CNAO, Pavia, Italy) synchrotron facility, has already been successfully tested in vivo during a proton therapy treatment. We discuss here the system performance evaluation with carbon ion beams, in view of future in vivo tests. The work is focused on the analysis of activity images obtained with therapeutic treatments delivered to polymethyl methacrylate (PMMA) phantoms, as well as on the test of an innovative and robust Monte Carlo simulation technique for the production of reliable prior activity maps. Images are reconstructed using different integration intervals, so as to monitor the activity evolution during and after the treatment. Three procedures to compare activity images are presented, namely Pearson correlation coefficient, Beam's eye view and overall view. Images of repeated irradiations of the same treatments are compared to assess the integration time necessary to provide reproducible images. The range agreement between simulated and experimental images is also evaluated, so as to validate the simulation capability to provide sound prior information. The results indicate that at treatment end, or at most 20 s afterwards, the range measurement is reliable within 1-2 mm, when comparing both different experimental sessions and data with simulations. In conclusion, this work shows that the INSIDE in-beam PET scanner performance is promising towards its in vivo test with carbon ions.
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22
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Lin YS, Chao TC, Hong JH, Tung CJ. Comparisons of longitudinal and lateral dose profiles and relative biological effectiveness for DNA double strand breaks among 1H, 4He and 12C beams. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2016.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Min E, Kim K, Lee H, Kim HI, Chung YH, Kim Y, Joung J, Kim KM, Joo SK, Lee K. Development of Compact, Cost-effective, FPGA-Based Data Acquisition System for the iPET System. J Med Biol Eng 2017. [DOI: 10.1007/s40846-017-0245-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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24
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Berndt B, Landry G, Schwarz F, Tessonnier T, Kamp F, Dedes G, Thieke C, Würl M, Kurz C, Ganswindt U, Verhaegen F, Debus J, Belka C, Sommer W, Reiser M, Bauer J, Parodi K. Application of single- and dual-energy CT brain tissue segmentation to PET monitoring of proton therapy. Phys Med Biol 2017; 62:2427-2448. [DOI: 10.1088/1361-6560/aa5f9f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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25
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Traini G, Battistoni G, Bollella A, Collamati F, De Lucia E, Faccini R, Ferroni F, Frallicciardi PM, Mancini-Terracciano C, Marafini M, Mattei I, Miraglia F, Muraro S, Paramatti R, Piersanti L, Pinci D, Rucinski A, Russomando A, Sarti A, Sciubba A, Senzacqua M, Solfaroli-Camillocci E, Toppi M, Voena C, Patera V. Design of a new tracking device for on-line beam range monitor in carbon therapy. Phys Med 2017; 34:18-27. [PMID: 28111101 DOI: 10.1016/j.ejmp.2017.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 11/02/2016] [Accepted: 01/03/2017] [Indexed: 10/20/2022] Open
Abstract
Charged particle therapy is a technique for cancer treatment that exploits hadron beams, mostly protons and carbon ions. A critical issue is the monitoring of the beam range so to check the correct dose deposition to the tumor and surrounding tissues. The design of a new tracking device for beam range real-time monitoring in pencil beam carbon ion therapy is presented. The proposed device tracks secondary charged particles produced by beam interactions in the patient tissue and exploits the correlation of the charged particle emission profile with the spatial dose deposition and the Bragg peak position. The detector, currently under construction, uses the information provided by 12 layers of scintillating fibers followed by a plastic scintillator and a pixelated Lutetium Fine Silicate (LFS) crystal calorimeter. An algorithm to account and correct for emission profile distortion due to charged secondaries absorption inside the patient tissue is also proposed. Finally detector reconstruction efficiency for charged particle emission profile is evaluated using a Monte Carlo simulation considering a quasi-realistic case of a non-homogenous phantom.
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Affiliation(s)
- Giacomo Traini
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | | | - Angela Bollella
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Francesco Collamati
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Erika De Lucia
- Laboratori Nazionali di Frascati dell'INFN (LNF), Via Enrico Fermi 40, 00044 Frascati(Roma), Italy
| | - Riccardo Faccini
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Fernando Ferroni
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | | | - Carlo Mancini-Terracciano
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Michela Marafini
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy
| | - Ilaria Mattei
- INFN Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
| | - Federico Miraglia
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Silvia Muraro
- INFN Sezione di Milano, Via Celoria 16, 20133 Milano, Italy
| | - Riccardo Paramatti
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Luca Piersanti
- Laboratori Nazionali di Frascati dell'INFN (LNF), Via Enrico Fermi 40, 00044 Frascati(Roma), Italy
| | - Davide Pinci
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Antoni Rucinski
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy
| | - Andrea Russomando
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Alessio Sarti
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy
| | - Adalberto Sciubba
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy; Museo Storico della Fisica e Centro Studi e Ricerche "E. Fermi", P.zza del Viminale, 00184 Roma, Italy
| | - Martina Senzacqua
- Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy
| | - Elena Solfaroli-Camillocci
- Dipartimento di Fisica, Sapienza Università di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy
| | - Marco Toppi
- Laboratori Nazionali di Frascati dell'INFN (LNF), Via Enrico Fermi 40, 00044 Frascati(Roma), Italy
| | - Cecilia Voena
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy.
| | - Vincenzo Patera
- INFN Sezione di Roma, Pl.e Aldo Moro 2, 00185 Roma, Italy; Dipartimento di Scienze di Base e Applicate per Ingegneria (SBAI), Sapienza Università di Roma, Via Antonio Scarpa 14, 00161 Roma, Italy; Museo Storico della Fisica e Centro Studi e Ricerche "E. Fermi", P.zza del Viminale, 00184 Roma, Italy
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Durante M, Paganetti H. Nuclear physics in particle therapy: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:096702. [PMID: 27540827 DOI: 10.1088/0034-4885/79/9/096702] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Charged particle therapy has been largely driven and influenced by nuclear physics. The increase in energy deposition density along the ion path in the body allows reducing the dose to normal tissues during radiotherapy compared to photons. Clinical results of particle therapy support the physical rationale for this treatment, but the method remains controversial because of the high cost and of the lack of comparative clinical trials proving the benefit compared to x-rays. Research in applied nuclear physics, including nuclear interactions, dosimetry, image guidance, range verification, novel accelerators and beam delivery technologies, can significantly improve the clinical outcome in particle therapy. Measurements of fragmentation cross-sections, including those for the production of positron-emitting fragments, and attenuation curves are needed for tuning Monte Carlo codes, whose use in clinical environments is rapidly increasing thanks to fast calculation methods. Existing cross sections and codes are indeed not very accurate in the energy and target regions of interest for particle therapy. These measurements are especially urgent for new ions to be used in therapy, such as helium. Furthermore, nuclear physics hardware developments are frequently finding applications in ion therapy due to similar requirements concerning sensors and real-time data processing. In this review we will briefly describe the physics bases, and concentrate on the open issues.
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Affiliation(s)
- Marco Durante
- Trento Institute for Fundamental Physics and Applications (TIFPA), National Institute of Nuclear Physics (INFN), University of Trento, Via Sommarive 14, 38123 Povo (TN), Italy. Department of Physics, University Federico II, Naples, Italy
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Battistoni G, Bauer J, Boehlen TT, Cerutti F, Chin MPW, Dos Santos Augusto R, Ferrari A, Ortega PG, Kozłowska W, Magro G, Mairani A, Parodi K, Sala PR, Schoofs P, Tessonnier T, Vlachoudis V. The FLUKA Code: An Accurate Simulation Tool for Particle Therapy. Front Oncol 2016; 6:116. [PMID: 27242956 PMCID: PMC4863153 DOI: 10.3389/fonc.2016.00116] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 04/25/2016] [Indexed: 12/02/2022] Open
Abstract
Monte Carlo (MC) codes are increasingly spreading in the hadrontherapy community due to their detailed description of radiation transport and interaction with matter. The suitability of a MC code for application to hadrontherapy demands accurate and reliable physical models capable of handling all components of the expected radiation field. This becomes extremely important for correctly performing not only physical but also biologically based dose calculations, especially in cases where ions heavier than protons are involved. In addition, accurate prediction of emerging secondary radiation is of utmost importance in innovative areas of research aiming at in vivo treatment verification. This contribution will address the recent developments of the FLUKA MC code and its practical applications in this field. Refinements of the FLUKA nuclear models in the therapeutic energy interval lead to an improved description of the mixed radiation field as shown in the presented benchmarks against experimental data with both (4)He and (12)C ion beams. Accurate description of ionization energy losses and of particle scattering and interactions lead to the excellent agreement of calculated depth-dose profiles with those measured at leading European hadron therapy centers, both with proton and ion beams. In order to support the application of FLUKA in hospital-based environments, Flair, the FLUKA graphical interface, has been enhanced with the capability of translating CT DICOM images into voxel-based computational phantoms in a fast and well-structured way. The interface is capable of importing also radiotherapy treatment data described in DICOM RT standard. In addition, the interface is equipped with an intuitive PET scanner geometry generator and automatic recording of coincidence events. Clinically, similar cases will be presented both in terms of absorbed dose and biological dose calculations describing the various available features.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Giuseppe Magro
- Centro Nazionale di Adroterapia Oncologica, Pavia, Italy
| | - Andrea Mairani
- Centro Nazionale di Adroterapia Oncologica, Pavia, Italy
- Heidelberger Ionenstrahl-Therapiezentrum (HIT), Heidelberg, Germany
| | - Katia Parodi
- Ludwig Maximilian University of Munich, Munich, Germany
- Heidelberger Ionenstrahl-Therapiezentrum (HIT), Heidelberg, Germany
| | - Paola R. Sala
- INFN Sezione di Milano, Milan, Italy
- CERN, Geneva, Switzerland
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28
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Kurz C, Bauer J, Conti M, Guérin L, Eriksson L, Parodi K. Investigating the limits of PET/CT imaging at very low true count rates and high random fractions in ion-beam therapy monitoring. Med Phys 2016; 42:3979-91. [PMID: 26133598 DOI: 10.1118/1.4921995] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE External beam radiotherapy with protons and heavier ions enables a tighter conformation of the applied dose to arbitrarily shaped tumor volumes with respect to photons, but is more sensitive to uncertainties in the radiotherapeutic treatment chain. Consequently, an independent verification of the applied treatment is highly desirable. For this purpose, the irradiation-induced β(+)-emitter distribution within the patient is detected shortly after irradiation by a commercial full-ring positron emission tomography/x-ray computed tomography (PET/CT) scanner installed next to the treatment rooms at the Heidelberg Ion-Beam Therapy Center (HIT). A major challenge to this approach is posed by the small number of detected coincidences. This contribution aims at characterizing the performance of the used PET/CT device and identifying the best-performing reconstruction algorithm under the particular statistical conditions of PET-based treatment monitoring. Moreover, this study addresses the impact of radiation background from the intrinsically radioactive lutetium-oxyorthosilicate (LSO)-based detectors at low counts. METHODS The authors have acquired 30 subsequent PET scans of a cylindrical phantom emulating a patientlike activity pattern and spanning the entire patient counting regime in terms of true coincidences and random fractions (RFs). Accuracy and precision of activity quantification, image noise, and geometrical fidelity of the scanner have been investigated for various reconstruction algorithms and settings in order to identify a practical, well-suited reconstruction scheme for PET-based treatment verification. Truncated listmode data have been utilized for separating the effects of small true count numbers and high RFs on the reconstructed images. A corresponding simulation study enabled extending the results to an even wider range of counting statistics and to additionally investigate the impact of scatter coincidences. Eventually, the recommended reconstruction scheme has been applied to exemplary postirradiation patient data-sets. RESULTS Among the investigated reconstruction options, the overall best results in terms of image noise, activity quantification, and accurate geometrical recovery were achieved using the ordered subset expectation maximization reconstruction algorithm with time-of-flight (TOF) and point-spread function (PSF) information. For this algorithm, reasonably accurate (better than 5%) and precise (uncertainty of the mean activity below 10%) imaging can be provided down to 80,000 true coincidences at 96% RF. Image noise and geometrical fidelity are generally improved for fewer iterations. The main limitation for PET-based treatment monitoring has been identified in the small number of true coincidences, rather than the high intrinsic random background. Application of the optimized reconstruction scheme to patient data-sets results in a 25% - 50% reduced image noise at a comparable activity quantification accuracy and an improved geometrical performance with respect to the formerly used reconstruction scheme at HIT, adopted from nuclear medicine applications. CONCLUSIONS Under the poor statistical conditions in PET-based treatment monitoring, improved results can be achieved by considering PSF and TOF information during image reconstruction and by applying less iterations than in conventional nuclear medicine imaging. Geometrical fidelity and image noise are mainly limited by the low number of true coincidences, not the high LSO-related random background. The retrieved results might also impact other emerging PET applications at low counting statistics.
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Affiliation(s)
- Christopher Kurz
- Heidelberg Ion-Beam Therapy Center and Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany
| | - Julia Bauer
- Heidelberg Ion-Beam Therapy Center and Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany
| | - Maurizio Conti
- Siemens Healthcare Molecular Imaging, Knoxville, Tennessee 37932
| | - Laura Guérin
- Siemens Healthcare Molecular Imaging, Knoxville, Tennessee 37932
| | - Lars Eriksson
- Siemens Healthcare Molecular Imaging, Knoxville, Tennessee 37932
| | - Katia Parodi
- Heidelberg Ion-Beam Therapy Center and Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany and Department of Experimental Physics - Medical Physics, Ludwig-Maximilians-University, Munich 85748, Germany
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Cho J, Campbell P, Wang M, Alqathami M, Mawlawi O, Kerr M, Cho SH. Feasibility of hydrogel fiducial markers forin vivoproton range verification using PET. Phys Med Biol 2016; 61:2162-76. [DOI: 10.1088/0031-9155/61/5/2162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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De Bernardi E, Ricotti R, Riboldi M, Baroni G, Parodi K, Gianoli C. 4D ML reconstruction as a tool for volumetric PET-based treatment verification in ion beam radiotherapy. Med Phys 2016; 43:710-26. [DOI: 10.1118/1.4939227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Abstract
The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy.
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Affiliation(s)
- Wayne D Newhauser
- Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA, 70803, USA
- Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA, 70809, USA
| | - Rui Zhang
- Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA, 70803, USA
- Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA, 70809, USA
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Grogg K, Alpert NM, Zhu X, Min CH, Testa M, Winey B, Normandin MD, Shih HA, Paganetti H, Bortfeld T, El Fakhri G. Mapping (15)O production rate for proton therapy verification. Int J Radiat Oncol Biol Phys 2015; 92:453-9. [PMID: 25817530 DOI: 10.1016/j.ijrobp.2015.01.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/10/2014] [Accepted: 01/15/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE This work was a proof-of-principle study for the evaluation of oxygen-15 ((15)O) production as an imaging target through the use of positron emission tomography (PET), to improve verification of proton treatment plans and to study the effects of perfusion. METHODS AND MATERIALS Dynamic PET measurements of irradiation-produced isotopes were made for a phantom and rabbit thigh muscles. The rabbit muscle was irradiated and imaged under both live and dead conditions. A differential equation was fitted to phantom and in vivo data, yielding estimates of (15)O production and clearance rates, which were compared to live versus dead rates for the rabbit and to Monte Carlo predictions. RESULTS PET clearance rates agreed with decay constants of the dominant radionuclide species in 3 different phantom materials. In 2 oxygen-rich materials, the ratio of (15)O production rates agreed with the expected ratio. In the dead rabbit thighs, the dynamic PET concentration histories were accurately described using (15)O decay constant, whereas the live thigh activity decayed faster. Most importantly, the (15)O production rates agreed within 2% (P>.5) between conditions. CONCLUSIONS We developed a new method for quantitative measurement of (15)O production and clearance rates in the period immediately following proton therapy. Measurements in the phantom and rabbits were well described in terms of (15)O production and clearance rates, plus a correction for other isotopes. These proof-of-principle results support the feasibility of detailed verification of proton therapy treatment delivery. In addition, (15)O clearance rates may be useful in monitoring permeability changes due to therapy.
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Affiliation(s)
- Kira Grogg
- Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts
| | - Nathaniel M Alpert
- Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts
| | - Xuping Zhu
- Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts
| | - Chul Hee Min
- Department of Radiological Science, College of Health Science, Yonsei University, Wonju, Kangwon, Korea
| | - Mauro Testa
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Brian Winey
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Marc D Normandin
- Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts
| | - Helen A Shih
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Thomas Bortfeld
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Georges El Fakhri
- Center for Advanced Radiological Sciences, Nuclear Medicine and Molecular Imaging, Radiology Department, Massachusetts General Hospital, Boston, Massachusetts.
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Gianoli C, Bauer J, Riboldi M, De Bernardi E, Fattori G, Baselli G, Debus J, Parodi K, Baroni G. Regional MLEM reconstruction strategy for PET-based treatment verification in ion beam radiotherapy. Phys Med Biol 2014; 59:6979-95. [DOI: 10.1088/0031-9155/59/22/6979] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Subiel A, Moskvin V, Welsh GH, Cipiccia S, Reboredo D, Evans P, Partridge M, DesRosiers C, Anania MP, Cianchi A, Mostacci A, Chiadroni E, Di Giovenale D, Villa F, Pompili R, Ferrario M, Belleveglia M, Di Pirro G, Gatti G, Vaccarezza C, Seitz B, Isaac RC, Brunetti E, Wiggins SM, Ersfeld B, Islam MR, Mendonca MS, Sorensen A, Boyd M, Jaroszynski DA. Dosimetry of very high energy electrons (VHEE) for radiotherapy applications: using radiochromic film measurements and Monte Carlo simulations. Phys Med Biol 2014; 59:5811-29. [PMID: 25207591 DOI: 10.1088/0031-9155/59/19/5811] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Very high energy electrons (VHEE) in the range from 100-250 MeV have the potential of becoming an alternative modality in radiotherapy because of their improved dosimetry properties compared with MV photons from contemporary medical linear accelerators. Due to the need for accurate dosimetry of small field size VHEE beams we have performed dose measurements using EBT2 Gafchromic® film. Calibration of the film has been carried out for beams of two different energy ranges: 20 MeV and 165 MeV from conventional radio frequency linear accelerators. In addition, EBT2 film has been used for dose measurements with 135 MeV electron beams produced by a laser-plasma wakefield accelerator. The dose response measurements and percentage depth dose profiles have been compared with calculations carried out using the general-purpose FLUKA Monte Carlo (MC) radiation transport code. The impact of induced radioactivity on film response for VHEEs has been evaluated using the MC simulations. A neutron yield of the order of 10(-5) neutrons cm(-2) per incident electron has been estimated and induced activity due to radionuclide production is found to have a negligible effect on total dose deposition and film response. Neutron and proton contribution to the equivalent doses are negligible for VHEE. The study demonstrates that EBT2 Gafchromic film is a reliable dosimeter that can be used for dosimetry of VHEE. The results indicate an energy-independent response of the dosimeter for 20 MeV and 165 MeV electron beams and has been found to be suitable for dosimetry of VHEE.
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Affiliation(s)
- A Subiel
- Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow G4 0NG, UK
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Frey K, Unholtz D, Bauer J, Debus J, Min CH, Bortfeld T, Paganetti H, Parodi K. Automation and uncertainty analysis of a method for in-vivo range verification in particle therapy. Phys Med Biol 2014; 59:5903-19. [PMID: 25211629 PMCID: PMC10008084 DOI: 10.1088/0031-9155/59/19/5903] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We introduce the automation of the range difference calculation deduced from particle-irradiation induced β(+)-activity distributions with the so-called most-likely-shift approach, and evaluate its reliability via the monitoring of algorithm- and patient-specific uncertainty factors. The calculation of the range deviation is based on the minimization of the absolute profile differences in the distal part of two activity depth profiles shifted against each other. Depending on the workflow of positron emission tomography (PET)-based range verification, the two profiles under evaluation can correspond to measured and simulated distributions, or only measured data from different treatment sessions. In comparison to previous work, the proposed approach includes an automated identification of the distal region of interest for each pair of PET depth profiles and under consideration of the planned dose distribution, resulting in the optimal shift distance. Moreover, it introduces an estimate of uncertainty associated to the identified shift, which is then used as weighting factor to 'red flag' problematic large range differences. Furthermore, additional patient-specific uncertainty factors are calculated using available computed tomography (CT) data to support the range analysis. The performance of the new method for in-vivo treatment verification in the clinical routine is investigated with in-room PET images for proton therapy as well as with offline PET images for proton and carbon ion therapy. The comparison between measured PET activity distributions and predictions obtained by Monte Carlo simulations or measurements from previous treatment fractions is performed. For this purpose, a total of 15 patient datasets were analyzed, which were acquired at Massachusetts General Hospital and Heidelberg Ion-Beam Therapy Center with in-room PET and offline PET/CT scanners, respectively. Calculated range differences between the compared activity distributions are reported in a 2D map in beam-eye-view. In comparison to previously proposed approaches, the new most-likely-shift method shows more robust results for assessing in-vivo the range from strongly varying PET distributions caused by differing patient geometry, ion beam species, beam delivery techniques, PET imaging concepts and counting statistics. The additional visualization of the uncertainties and the dedicated weighting strategy contribute to the understanding of the reliability of observed range differences and the complexity in the prediction of activity distributions. The proposed method promises to offer a feasible technique for clinical routine of PET-based range verification.
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Affiliation(s)
- K Frey
- Ludwig Maximilians University, Munich, Germany
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Jabbari K, Seuntjens J. A fast Monte Carlo code for proton transport in radiation therapy based on MCNPX. J Med Phys 2014; 39:156-63. [PMID: 25190994 PMCID: PMC4154183 DOI: 10.4103/0971-6203.139004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 04/10/2014] [Accepted: 04/23/2014] [Indexed: 11/04/2022] Open
Abstract
An important requirement for proton therapy is a software for dose calculation. Monte Carlo is the most accurate method for dose calculation, but it is very slow. In this work, a method is developed to improve the speed of dose calculation. The method is based on pre-generated tracks for particle transport. The MCNPX code has been used for generation of tracks. A set of data including the track of the particle was produced in each particular material (water, air, lung tissue, bone, and soft tissue). This code can transport protons in wide range of energies (up to 200 MeV for proton). The validity of the fast Monte Carlo (MC) code is evaluated with data MCNPX as a reference code. While analytical pencil beam algorithm transport shows great errors (up to 10%) near small high density heterogeneities, there was less than 2% deviation of MCNPX results in our dose calculation and isodose distribution. In terms of speed, the code runs 200 times faster than MCNPX. In the Fast MC code which is developed in this work, it takes the system less than 2 minutes to calculate dose for 10(6) particles in an Intel Core 2 Duo 2.66 GHZ desktop computer.
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Affiliation(s)
- Keyvan Jabbari
- Department of Medical Physics and Engineering, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Jan Seuntjens
- Medical Physics Unit, McGill University Health Center, Montréal, Québec, Canada
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Bauer J, Sommerer F, Mairani A, Unholtz D, Farook R, Handrack J, Frey K, Marcelos T, Tessonnier T, Ecker S, Ackermann B, Ellerbrock M, Debus J, Parodi K. Integration and evaluation of automated Monte Carlo simulations in the clinical practice of scanned proton and carbon ion beam therapy. Phys Med Biol 2014; 59:4635-59. [DOI: 10.1088/0031-9155/59/16/4635] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Proton range monitoring with in-beam PET: Monte Carlo activity predictions and comparison with cyclotron data. Phys Med 2014; 30:559-69. [DOI: 10.1016/j.ejmp.2014.04.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 04/03/2014] [Accepted: 04/06/2014] [Indexed: 11/17/2022] Open
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Gianoli C, Riboldi M, Kurz C, De Bernardi E, Bauer J, Fontana G, Ciocca M, Parodi K, Baroni G. PET-CT scanner characterization for PET raw data use in biomedical research. Comput Med Imaging Graph 2014; 38:358-68. [DOI: 10.1016/j.compmedimag.2014.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 03/11/2014] [Accepted: 03/24/2014] [Indexed: 11/27/2022]
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40
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Shao Y, Sun X, Lou K, Zhu XR, Mirkovic D, Poenisch F, Grosshans D. In-beam PET imaging for on-line adaptive proton therapy: an initial phantom study. Phys Med Biol 2014; 59:3373-88. [DOI: 10.1088/0031-9155/59/13/3373] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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41
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Miyatake A, Nishio T. Application of activity pencil beam algorithm using measured distribution data of positron emitter nuclei for therapeutic SOBP proton beam. Med Phys 2014; 40:091709. [PMID: 24007142 DOI: 10.1118/1.4818057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Recently, much research on imaging the clinical proton-irradiated volume using positron emitter nuclei based on target nuclear fragment reaction has been carried out. The purpose of this study is to develop an activity pencil beam (APB) algorithm for a simulation system for proton-activated positron-emitting imaging in clinical proton therapy using spread-out Bragg peak (SOBP) beams. METHODS The target nuclei of activity distribution calculations are (12)C nuclei, (16)O nuclei, and (40)Ca nuclei, which are the main elements in a human body. Depth activity distributions with SOBP beam irradiations were obtained from the material information of ridge filter (RF) and depth activity distributions of compounds of the three target nuclei measured by BOLPs-RGp (beam ON-LINE PET system mounted on a rotating gantry port) with mono-energetic Bragg peak (MONO) beam irradiations. The calculated data of depth activity distributions with SOBP beam irradiations were sorted in terms of kind of nucleus, energy of proton beam, SOBP width, and thickness of fine degrader (FD), which were verified. The calculated depth activity distributions with SOBP beam irradiations were compared with the measured ones. APB kernels were made from the calculated depth activity distributions with SOBP beam irradiations to construct a simulation system using the APB algorithm for SOBP beams. RESULTS The depth activity distributions were prepared using the material information of RF and the measured depth activity distributions with MONO beam irradiations for clinical therapy using SOBP beams. With the SOBP width widening, the distal fall-offs of depth activity distributions and the difference from the depth dose distributions were large. The shapes of the calculated depth activity distributions nearly agreed with those of the measured ones upon comparison between the two. The APB kernels of SOBP beams were prepared by making use of the data on depth activity distributions with SOBP beam irradiations that were made from the depth activity distributions with MONO beam irradiations and sorted in terms of energy, SOBP width, and thickness of FD. The data on APB kernels of SOBP beams were determined as installment data for the simulation system using the APB algorithm for SOBP beam irradiations. CONCLUSIONS A method of obtaining the depth activity distributions and the APB algorithm for clinical use of SOBP beams have been developed. It is suggested that the simulation system for imaging the clinical irradiated volume with the APB algorithm can be used in clinical proton therapy using SOBP beams by preparing and investigating the data on APB kernels of SOBP beams.
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Affiliation(s)
- Aya Miyatake
- Keen Medical Physics Co. Ltd., 901-4-4-4 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan.
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Bueno M, Paganetti H, Duch MA, Schuemann J. An algorithm to assess the need for clinical Monte Carlo dose calculation for small proton therapy fields based on quantification of tissue heterogeneity. Med Phys 2014; 40:081704. [PMID: 23927301 DOI: 10.1118/1.4812682] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
PURPOSE In proton therapy, complex density heterogeneities within the beam path constitute a challenge to dose calculation algorithms. This might question the reliability of dose distributions predicted by treatment planning systems based on analytical dose calculation. For cases in which substantial dose errors are expected, resorting to Monte Carlo dose calculations might be essential to ensure a successful treatment outcome and therefore the benefit is worth a presumably long computation time. The aim of this study was to define an indicator for the accuracy of dose delivery based on analytical dose calculations in treatment planning systems for small proton therapy fields to identify those patients for which Monte Carlo dose calculation is warranted. METHODS Fourteen patients treated at our facility with small passively scattered proton beams (apertures diameters below 7 cm) were selected. Plans were generated in the XiO treatment planning system in combination with a pencil beam algorithm developed at the Massachusetts General Hospital and compared to Monte Carlo dose calculations. Differences in the dose to the 50% of the gross tumor volume (D50, GTV) were assessed in a field-by-field basis. A simple and fast methodology was developed to quantify the inhomogeneity of the tissue traversed by a single small proton beam using a heterogeneity index (HI)-a concept presented by Plugfelder et al. [Med. Phys. 34, 1506-1513 (2007)] for scanned proton beams. Finally, the potential correlation between the error made by the pencil beam based treatment planning algorithm for each field and the level of tissue heterogeneity traversed by the proton beam given by the HI was evaluated. RESULTS Discrepancies up to 5.4% were found in D50 for single fields, although dose differences were within clinical tolerance levels (<3%) when combining all of the fields involved in the treatment. The discrepancies found for each field exhibited a strong correlation to their associated HI-values (Spearman's ρ=0.8, p<0.0001); the higher the level of tissue inhomogeneities for a particular field, the larger the error by the analytical algorithm. With the established correlation a threshold for HI can be set by choosing a tolerance level of 2-3%-commonly accepted in radiotherapy. CONCLUSIONS The HI is a good indicator for the accuracy of proton field delivery in terms of GTV prescription dose coverage when small fields are delivered. Each HI-value was obtained from the CT image in less than 3 min on a computer with 2 GHz CPU allowing implementation of this methodology in clinical routine. For HI-values exceeding the threshold, either a change in beam direction (if feasible) or a recalculation of the dose with Monte Carlo would be highly recommended.
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Affiliation(s)
- M Bueno
- Departament de Dosimetria i Física Mèdica, Institut de Tècniques Energètiques, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain.
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Verburg JM, Seco J. Dosimetric accuracy of proton therapy for chordoma patients with titanium implants. Med Phys 2014; 40:071727. [PMID: 23822431 DOI: 10.1118/1.4810942] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To investigate dosimetric errors in proton therapy treatment planning due to titanium implants, and to determine how these affect postoperative passively scattered proton therapy for chordoma patients with orthopedic hardware. METHODS The presence of titanium hardware near the tumor may affect the dosimetric accuracy of proton therapy. Artifacts in the computed tomography (CT) scan can cause errors in the proton stopping powers used for dose calculation, which are derived from CT numbers. Also, clinical dose calculation algorithms may not accurately simulate proton beam transport through the implants, which have very different properties as compared to human tissue. The authors first evaluated the impact of these two main issues. Dose errors introduced by metal artifacts were studied using phantoms with and without titanium inserts, and patient scans on which a metal artifact reduction method was applied. Pencil-beam dose calculations were compared to models of nuclear interactions in titanium and Monte Carlo simulations. Then, to assess the overall impact on treatment plans for chordoma, the authors compared the original clinical treatment plans to recalculated dose distributions employing both metal artifact reduction and Monte Carlo methods. RESULTS Dose recalculations of clinical proton fields showed that metal artifacts cause range errors up to 6 mm distal to regions affected by CT artifacts. Monte Carlo simulations revealed dose differences >10% in the high-dose area, and range differences up to 10 mm. Since these errors are mostly local in nature, the large number of fields limits the impact on target coverage in the chordoma treatment plans to a small decrease of dose homogeneity. CONCLUSIONS In the presence of titanium implants, CT metal artifacts and the approximations of pencil-beam dose calculations cause considerable errors in proton dose calculation. The spatial distribution of the errors however limits the overall impact on passively scattered proton therapy for chordoma.
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Affiliation(s)
- Joost M Verburg
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
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Sportelli G, Belcari N, Camarlinghi N, Cirrone GAP, Cuttone G, Ferretti S, Kraan A, Ortuño JE, Romano F, Santos A, Straub K, Tramontana A, Guerra AD, Rosso V. First full-beam PET acquisitions in proton therapy with a modular dual-head dedicated system. Phys Med Biol 2013; 59:43-60. [DOI: 10.1088/0031-9155/59/1/43] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Frey K, Bauer J, Unholtz D, Kurz C, Krämer M, Bortfeld T, Parodi K. TPSPET—A TPS-based approach forin vivodose verification with PET in proton therapy. Phys Med Biol 2013; 59:1-21. [DOI: 10.1088/0031-9155/59/1/1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Furukawa T, Inaniwa T, Hara Y, Mizushima K, Shirai T, Noda K. Patient-specific QA and delivery verification of scanned ion beam at NIRS-HIMAC. Med Phys 2013; 40:121707. [DOI: 10.1118/1.4828845] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Cho J, Ibbott G, Gillin M, Gonzalez-Lepera C, Titt U, Paganetti H, Kerr M, Mawlawi O. Feasibility of proton-activated implantable markers for proton range verification using PET. Phys Med Biol 2013; 58:7497-512. [PMID: 24099853 DOI: 10.1088/0031-9155/58/21/7497] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Proton beam range verification using positron emission tomography (PET) currently relies on proton activation of tissue, the products of which decay with a short half-life and necessitate an on-site PET scanner. Tissue activation is, however, negligible near the distal dose fall-off region of the proton beam range due to their high interaction energy thresholds. Therefore Monte Carlo simulation is often supplemented for comparison with measurement; however, this also may be associated with systematic and statistical uncertainties. Therefore, we sought to test the feasibility of using long-lived proton-activated external materials that are inserted or infused into the target volume for more accurate proton beam range verification that could be performed at an off-site PET scanner. We irradiated samples of ≥98% (18)O-enriched water, natural Cu foils, and >97% (68)Zn-enriched foils as candidate materials, along with samples of tissue-equivalent materials including (16)O water, heptane (C7H16), and polycarbonate (C16H14O3)n, at four depths (ranging from 100% to 3% of center of modulation (COM) dose) along the distal fall-off of a modulated 160 MeV proton beam. Samples were irradiated either directly or after being embedded in Plastic Water® or balsa wood. We then measured the activity of the samples using PET imaging for 20 or 30 min after various delay times. Measured activities of candidate materials were up to 100 times greater than those of the tissue-equivalent materials at the four distal dose fall-off depths. The differences between candidate materials and tissue-equivalent materials became more apparent after longer delays between irradiation and PET imaging, due to the longer half-lives of the candidate materials. Furthermore, the activation of the candidate materials closely mimicked the distal dose fall-off with offsets of 1 to 2 mm. Also, signals from the foils were clearly visible compared to the background from the activated Plastic Water® and balsa wood phantoms. These results indicate that markers made from these candidate materials could be used for in vivo proton range verification using an off-site PET scanner.
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Affiliation(s)
- Jongmin Cho
- Graduate School of Biomedical Sciences at Houston, The University of Texas, Houston, TX 77030, USA. Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Zhu X, Fakhri GE. Proton therapy verification with PET imaging. Theranostics 2013; 3:731-40. [PMID: 24312147 PMCID: PMC3840408 DOI: 10.7150/thno.5162] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 08/28/2013] [Indexed: 11/10/2022] Open
Abstract
Proton therapy is very sensitive to uncertainties introduced during treatment planning and dose delivery. PET imaging of proton induced positron emitter distributions is the only practical approach for in vivo, in situ verification of proton therapy. This article reviews the current status of proton therapy verification with PET imaging. The different data detecting systems (in-beam, in-room and off-line PET), calculation methods for the prediction of proton induced PET activity distributions, and approaches for data evaluation are discussed.
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Robert C, Fourrier N, Sarrut D, Stute S, Gueth P, Grevillot L, Buvat I. PET-based dose delivery verification in proton therapy: a GATE based simulation study of five PET system designs in clinical conditions. Phys Med Biol 2013; 58:6867-85. [DOI: 10.1088/0031-9155/58/19/6867] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Scholz R, Hoffmann F, von Sachsen S, Drossel WG, Klöhn C, Voigt C. Validation of density-elasticity relationships for finite element modeling of human pelvic bone by modal analysis. J Biomech 2013; 46:2667-73. [PMID: 24001928 DOI: 10.1016/j.jbiomech.2013.07.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 10/26/2022]
Abstract
In total hip arthroplasty and particularly in revision surgery, computer assisted pre-operative prediction of the best possible anchorage strategy for implant fixation would be a great help to the surgeon. Computer simulation relies on validated numerical models. In the current study, three density-elasticity relationships (No. 1-3) from the literature for inhomogeneous material parameter assignment from CT data in automated finite element (FE) modeling of long bones were evaluated for their suitability for FE modeling of human pelvic bone. Numerical modal analysis was conducted on 10 FE models of hemipelvic bone specimens and compared to the gold standard provided by experimental modal analysis results from a previous in-vitro study on the same specimens. Overall, calculated resonance frequencies came out lower than measured values. Magnitude of mean relative deviation of numerical resonance frequencies with regard to measured values is lowest for the density-elasticity relationship No. 3 (-15.9%) and considerably higher for both density-elasticity relationships No. 1 (-41.1%) and No. 2 (-45.0%). Mean MAC values over all specimens amount to 77.8% (No. 1), 78.5% (No. 2), and 83.0% (No. 3). MAC results show, that mode shapes are only slightly influenced by material distribution. Calculated resonance frequencies are generally lower than measured values, which indicates, that numerical models lack stiffness. Even when using the best suited (No. 3) out of three investigated density-elasticity relationships, in FE modeling of pelvic bone a considerable underestimation of model stiffness has to be taken into account.
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Affiliation(s)
- Roger Scholz
- University of Leipzig, Department of Orthopaedic Surgery, Laboratory for Biomechanics, Liebigstr. 20, 04103 Leipzig, Germany
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