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Rehani MM, Xu XG. Dose, dose, dose, but where is the patient dose? RADIATION PROTECTION DOSIMETRY 2024; 200:945-955. [PMID: 38847407 DOI: 10.1093/rpd/ncae137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/14/2024] [Accepted: 05/17/2024] [Indexed: 06/25/2024]
Abstract
The article reviews the historical developments in radiation dose metrices in medical imaging. It identifies the good, the bad, and the ugly aspects of current-day metrices. The actions on shifting focus from International Commission on Radiological Protection (ICRP) Reference-Man-based population-average phantoms to patient-specific computational phantoms have been proposed and discussed. Technological developments in recent years involving AI-based automatic organ segmentation and 'near real-time' Monte Carlo dose calculations suggest the feasibility and advantage of obtaining patient-specific organ doses. It appears that the time for ICRP and other international organizations to embrace 'patient-specific' dose quantity representing risk may have finally come. While the existing dose metrices meet specific demands, emphasis needs to be also placed on making radiation units understandable to the medical community.
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Affiliation(s)
- Madan M Rehani
- Massachusetts General Hospital, Radiology Department, Boston, MA, 02114, United States
| | - Xie George Xu
- University of Science and Technology of China (USTC), College of Nuclear Science & Technology, Hefei, Anhui Province, 230026, China
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2
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Wei Y, Dewji S. A comprehensive review of dose limits, triage systems and measurement tools for consequence management of nuclear and radiological emergencies. Radiat Phys Chem Oxf Engl 1993 2024; 217:111533. [PMID: 38882716 PMCID: PMC11170981 DOI: 10.1016/j.radphyschem.2024.111533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
During a radiological or nuclear emergency, occupational workers, members of the public, and emergency responders may be exposed to radionuclides, whether external or internal, through inhalation, ingestion, or wounds. In the case of internalized radiation exposure, prompt assessment of contamination is necessary to inform subsequent medical interventions. This review assembles the constituent considerations for managing nuclear and radiological incidents, focused on a parallel analysis of the evolution of radiation dose limits - notably in the emergency preparedness and response realm - alongside a discussion of triage systems and in vivo radionuclide detection tools. The review maps the development of international and national standards and regulations concerning radiation dose limits, illuminating how past incidents and accumulated knowledge have informed present emergency preparedness and response practices, specifically for internalized radiation. Additionally, the objectives and levels of radiation triage systems are explored in-depth, along with a global survey of practices and protocols. Finally, this review also focuses on in vivo detection systems and their capacities for radionuclide identification, prioritizing internalized gamma-emitting isotopes due to their broader relevance. Collectively, this study comprehensively addresses the intricacies of triage management following radiation emergencies, emphasizing the imperative for enhanced standardization and continued research in this critical domain.
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Affiliation(s)
- Y. Wei
- Nuclear and Radiological Engineering and Medical Physics Programs, Georgia Institute of Technology, 770 State Street NW, Atlanta, GA, 30332-0405, USA
| | - S.A. Dewji
- Nuclear and Radiological Engineering and Medical Physics Programs, Georgia Institute of Technology, 770 State Street NW, Atlanta, GA, 30332-0405, USA
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Muñoz-Hernández IS, Espinoza I, López-Martínez IN, Sánchez-Nieto B. IS 2aR, a computational tool to transform voxelized reference phantoms into patient-specific whole-body virtual CTs for peripheral dose estimation. Phys Med 2023; 116:103183. [PMID: 38000102 DOI: 10.1016/j.ejmp.2023.103183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 10/30/2023] [Accepted: 11/19/2023] [Indexed: 11/26/2023] Open
Abstract
BACKGROUND The risk of radiogenic cancer induction due to radiotherapy depends on the dose received by the patient's organs. Knowing the position of all organs is needed to assess this dose in a personalized way. However, radiotherapy planning computed tomography (pCT) scans contain truncated patient anatomy, limiting personalized dose evaluation. PURPOSE To develop a simple and freely available computational tool that adapts an ICRP reference computational phantom to generate a patient-specific whole-body CT for peripheral dose computations. METHODS Various bone-segmentation methods were explored onto fifteen pCTs, and the one with the highest Sørensen-Dice coefficient was implemented. The reference phantom is registered to the pCT, obtaining a registration transform matrix, which is then applied to create the whole-body virtual CT. Additional validation involved a comparison of absorbed doses to organs delineated on both the pCT and the virtual CT. RESULTS A dedicated graphical user interface was designed and implemented to house the developed functions for i) selecting a registration region on which automatic bone segmentation and rigid registration will occur, ii) displaying the results of these processes under selectable views, and iii) exporting the final patient-specific whole-body CT. This software was termed IS2aR. The tested whole-body virtual CT generated by IS2aR fulfilled our requirements. CONCLUSIONS IS2aR is a user-friendly computational software to create a personalized whole-body CT containing the original structures in the reference phantom. The personalized dose deposited in peripheral organs can be estimated further to assess second cancer induction risk in epidemiological studies.
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Affiliation(s)
| | - Ignacio Espinoza
- Institute of Physics, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Han H, Choi JW, Lee Y, Lee SM, Kim CH, Choi HJ, Yeom YS. An Investigation of Body Size Impact on Organ Doses for Neutron External Exposures Using the MRCP-based Phantom Library. HEALTH PHYSICS 2023; 124:316-325. [PMID: 36696362 DOI: 10.1097/hp.0000000000001672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
ABSTRACT In a recent study, a comprehensive library composed of 212 phantoms with different body sizes was established by deforming the adult male and female mesh-type reference computational phantoms (MRCPs) of ICRP Publication 145 and the next-generation ICRP reference phantoms over the current voxel-type reference phantoms of ICRP Publication 110. In this study, as an application of the MRCP-based phantom library, we investigated dosimetric impacts due to the different body sizes for neutron external exposures. A comprehensive dataset of organ/tissue dose coefficients (DCs) for idealized external neutron beams with four phantoms for each sex representatively selected from the phantom library were produced by performing Monte Carlo simulations using the Geant4 code. The body size-dependent DCs produced in this study were systematically analyzed, observing that the variation of the body weights overall played a more important role in organ/tissue dose calculations than the variation of the body heights. We also observed that the reference body-size DCs based on the MRCPs indeed significantly under- or overestimated the DCs produced using the phantoms, especially for those much heavier (male: 175 cm and 140 kg; female: 165 cm and 140 kg) than the reference body sizes (male: 176 cm and 73 kg; female: 163 cm and 60 kg) by up to 1.6 or 3.3 times, respectively. We believe that the use of the body size-dependent DCs, together with the reference body-size DCs, should be beneficial for more reliable organ/tissue dose estimates of individuals considering their body sizes rather than the most common conventional approach, i.e., the sole use of the reference body size DCs.
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Affiliation(s)
| | | | - Yumi Lee
- Department of Radiation Convergence Engineering, Yonsei University, Republic of Korea
| | - Soo Min Lee
- Department of Radiation Convergence Engineering, Yonsei University, Republic of Korea
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Republic of Korea
| | - Hyun Joon Choi
- Department of Radiation Oncology, Yonsei University Wonju College of Medicine, Republic of Korea
| | - Yeon Soo Yeom
- Department of Radiation Convergence Engineering, Yonsei University, Republic of Korea
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Kollitz E, Roew M, Han H, Pinto M, Kamp F, Kim CH, Schwarz M, Belka C, Newhauser W, Parodi K, Dedes G. Applications of a patient-specific whole-body CT-mesh hybrid computational phantom in second cancer risk prediction. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac8851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 08/09/2022] [Indexed: 11/11/2022]
Abstract
Abstract
Objective. CT-mesh hybrid phantoms (or ‘hybrid(s)’) made from integrated patient CT data and mesh-type reference computational phantoms (MRCPs) can be beneficial for patient-specific whole-body dose evaluation, but this benefit has yet to be evaluated for second cancer risk prediction. The purpose of this study is to compare the hybrid’s ability to predict risk throughout the body with a patient-scaled MRCP against ground truth whole-body CTs (WBCTs). Approach. Head and neck active scanning proton treatment plans were created for and simulated on seven hybrids and the corresponding scaled MRCPs and WBCTs. Equivalent dose throughout the body was calculated and input into five second cancer risk models for both excess absolute and excess relative risk (EAR and ERR). The hybrid phantom was evaluated by comparing equivalent dose and risk predictions against the WBCT. Main results. The hybrid most frequently provides whole-body second cancer risk predictions which are closer to the ground truth when compared to a scaled MRCP alone. The performance of the hybrid relative to the scaled MRCP was consistent across ERR, EAR, and all risk models. For all in-field organs, where the hybrid shares the WBCT anatomy, the hybrid was better than or equal to the scaled MRCP for both equivalent dose and risk prediction. For out-of-field organs across all patients, the hybrid’s equivalent dose prediction was superior than the scaled MRCP in 48% of all comparisons, equivalent for 34%, and inferior for 18%. For risk assessment in the same organs, the hybrid’s prediction was superior than the scaled MRCP in 51.8% of all comparisons, equivalent in 28.6%, and inferior in 19.6%. Significance. Whole-body risk predictions from the CT-mesh hybrid have shown to be more accurate than those from a reference phantom alone. These hybrids could aid in risk-optimized treatment planning and individual risk assessment to minimize second cancer incidence.
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Choi C, Shin B, Yeom YS, Nguyen TT, Han H, Kim S, Son G, Moon S, Kim H, Kim CH, Bolch WE, Jokisch DW, Lee C, Chung BS. Development of alimentary tract organs for ICRP pediatric mesh-type reference computational phantoms. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2022; 42:031508. [PMID: 35921807 DOI: 10.1088/1361-6498/ac8683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
In line with the activities of Task Group 103 under the International Commission on Radiological Protection (ICRP), the present study was conducted to develop a new set of alimentary tract organs consisting of the oral cavity, oesophagus, stomach, small intestine, and colon for the newborn, 1 year-old, 5 year-old, 10 year-old, and 15 year-old males and females for use in the pediatric mesh-type reference computational phantoms (MRCPs). The developed alimentary tract organs of the pediatric MRCPs, while nearly preserving the original topology and shape of those of the pediatric voxel-type reference computational phantoms (VRCPs) of ICRPPublication 143, present considerable anatomical improvement and include all micrometre-scale target and source regions as prescribed in ICRPPublication 100. To investigate the dosimetric impact of the developed alimentary tract organs, organ doses and specific absorbed fractions were computed for certain external exposures to photons and electrons and internal exposures to electrons, respectively, which were then compared with the values computed using the current ICRP models (i.e. pediatric VRCPs and ICRP-100 stylised models). The results showed that for external exposures to penetrating radiations (i.e. photons >0.04 MeV), there was generally good agreement between the compared values, within a 10% difference, except for the oral mucosa. For external exposures to weakly penetrating radiations (i.e. low-energy photons and electrons), there were significant differences, up to a factor of ∼8300, owing to the geometric difference caused by the anatomical enhancement in the MRCPs. For internal exposures of electrons, there were significant differences, the maximum of which reached a factor of ∼73 000. This was attributed not only to the geometric difference but also to the target mass difference caused by the different luminal content mass and organ shape.
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Affiliation(s)
- Chansoo Choi
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Bangho Shin
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Yeon Soo Yeom
- Department of Radiation Convergence Engineering, Yonsei University, Wonju, Republic of Korea
| | - Thang Tat Nguyen
- School of Nuclear Engineering and Environmental Physics, Hanoi University of Science and Technology, Hanoi, Vietnam
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Suhyeon Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Gahee Son
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sungho Moon
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Hyeonil Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Wesley E Bolch
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Derek W Jokisch
- Department of Physics and Engineering, Francis Marion University, Florence, SC, United States of America
- Center for Radiation Protection Knowledge, Oak Ridge National Laboratory, Oak Ridge, TN, United States of America
| | - Choonsik Lee
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States of America
| | - Beom Sun Chung
- Department of Anatomy, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
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Qu S, Xie T, Giger ML, Mao X, Zaidi H. Construction of A Digital Fetus Library for Radiation Dosimetry. Med Phys 2022; 50:2577-2589. [PMID: 35962972 DOI: 10.1002/mp.15905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 05/12/2022] [Accepted: 07/08/2022] [Indexed: 11/06/2022] Open
Abstract
PURPOSE Accurate estimation of fetal absorbed dose and radiation risks are crucial for radiation protection and important for radiological imaging research owing to the high radio-sensitivity of the fetus. Computational anthropomorphic models have been widely used in patient-specific radiation dosimetry calculations. In this work, we aim to build the first digital fetal library for more reliable and accurate radiation dosimetry studies. ACQUISITION AND VALIDATION METHODS Computed tomography (CT) images of abdominal and pelvic regions of 46 pregnant females were segmented by experienced medical physicists. The segmented tissues/organs include the body contour, skeleton, uterus, liver, kidney, intestine, stomach, lung, bladder, gall bladder, spleen and pancreas for maternal body, and placenta, amniotic fluid, fetal body, fetal brain and fetal skeleton. Non-Uniform Rational B-Spline (NURBS) surfaces of each identified region was constructed manually using 3D modeling software. The Hounsfield unit (HU) values of each identified organs were gathered from CT images of pregnant patients and converted to tissue density. Organ volumes were further adjusted according to reference measurements for the developing fetus recommended by the World Health Organization (WHO) and International Commission on Radiological Protection (ICRP). A series of anatomical parameters, including femur length (FL), humerus length (HL), biparietal diameter (BPD), abdominal circumference (FAC) and head circumference (HC) were measured and compared with WHO recommendations. DATA FORMAT AND USAGE NOTES The first fetal patient-specific model library was developed with the anatomical characteristics of each model derived from the corresponding patient whose gestational age varies between 8-weeks and 35-weeks. Voxelized models are represented in the form of MCNP matrix input files representing the three-dimensional model of the fetus. The size distributions of each model are also provided in text files. All data are stored on Zenodo and are publicly accessible on the following link: https://zenodo.org/record/6471884. POTENTIAL APPLICATIONS The constructed fetal models and maternal anatomical characteristics are consistent with the corresponding patients. The resulting computational fetus could be used in radiation dosimetry studies to improve the reliability of fetal dosimetry and radiation risks assessment. The advantages of NURBS surfaces in terms of adapting fetal postures and positions enable us to adequately assess their impact on radiation dosimetry calculations. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Shuiyin Qu
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China
| | - Tianwu Xie
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China.,Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva, CH-1211, Switzerland
| | - Maryellen L Giger
- Department of Radiology, Committee on Medical Physics, University of Chicago, Chicago, Illinois, United States
| | - Xianqing Mao
- Faculty of Science, Technology and Medicine (FSTM), Department of Life Sciences and Medicine, University of Luxembourg, Luxembourg
| | - Habib Zaidi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva, CH-1211, Switzerland.,Geneva Neuroscience Center, Geneva University, Geneva, CH-1205, Switzerland.,Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, Netherlands.,Department of Nuclear Medicine, University of Southern Denmark, Odense, DK-500, Denmark
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Fujiwara D, Shimomura T, Zhao W, Li KW, Haga A, Geng LS. Virtual computed-tomography system for deep-learning-based material decomposition. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac7bcd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/23/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. Material decomposition (MD) evaluates the elemental composition of human tissues and organs via computed tomography (CT) and is indispensable in correlating anatomical images with functional ones. A major issue in MD is inaccurate elemental information about the real human body. To overcome this problem, we developed a virtual CT system model, by which various reconstructed images can be generated based on ICRP110 human phantoms with information about six major elements (H, C, N, O, P, and Ca). Approach. We generated CT datasets labelled with accurate elemental information using the proposed generative CT model and trained a deep learning (DL)-based model to estimate the material distribution with the ICRP110 based human phantom as well as the digital Shepp–Logan phantom. The accuracy in quad-, dual-, and single-energy CT cases was investigated. The influence of beam-hardening artefacts, noise, and spectrum variations were analysed with testing datasets including elemental density and anatomical shape variations. Main results. The results indicated that this DL approach can realise precise MD, even with single-energy CT images. Moreover, noise, beam-hardening artefacts, and spectrum variations were shown to have minimal impact on the MD. Significance. Present results suggest that the difficulty to prepare a large CT database can be solved by introducing the virtual CT system and the proposed technique can be applied to clinical radiodiagnosis and radiotherapy.
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Yin Y, Wang X, Kong X, Zhang W, Wang Y, Mao Y, Wang J, Jia T, Tu Y, Zhang B, Sun L. Physical dosimetric reconstruction of a case of large area back skin injury due to overexposure in an interventional procedure. RADIATION MEDICINE AND PROTECTION 2022. [DOI: 10.1016/j.radmp.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Akhavanallaf A, Fayad H, Salimi Y, Aly A, Kharita H, Al Naemi H, Zaidi H. An update on computational anthropomorphic anatomical models. Digit Health 2022; 8:20552076221111941. [PMID: 35847523 PMCID: PMC9277432 DOI: 10.1177/20552076221111941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 06/19/2022] [Indexed: 11/15/2022] Open
Abstract
The prevalent availability of high-performance computing coupled with validated
computerized simulation platforms as open-source packages have motivated
progress in the development of realistic anthropomorphic computational models of
the human anatomy. The main application of these advanced tools focused on
imaging physics and computational internal/external radiation dosimetry
research. This paper provides an updated review of state-of-the-art developments
and recent advances in the design of sophisticated computational models of the
human anatomy with a particular focus on their use in radiation dosimetry
calculations. The consolidation of flexible and realistic computational models
with biological data and accurate radiation transport modeling tools enables the
capability to produce dosimetric data reflecting actual setup in clinical
setting. These simulation methodologies and results are helpful resources for
the medical physics and medical imaging communities and are expected to impact
the fields of medical imaging and dosimetry calculations profoundly.
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Affiliation(s)
- Azadeh Akhavanallaf
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva, Switzerland
| | - Hadi Fayad
- Hamad Medical Corporation, Doha, Qatar
- Weill Cornell Medicine, Doha, Qatar
| | - Yazdan Salimi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva, Switzerland
| | - Antar Aly
- Hamad Medical Corporation, Doha, Qatar
- Weill Cornell Medicine, Doha, Qatar
| | | | - Huda Al Naemi
- Hamad Medical Corporation, Doha, Qatar
- Weill Cornell Medicine, Doha, Qatar
| | - Habib Zaidi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva, Switzerland
- Geneva University Neurocenter, Geneva University, Geneva, Switzerland
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Nuclear Medicine, University of Southern Denmark, Odense, Denmark
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Cheon B, Lee SH, Han MC, Min CH, Han H, Kim CH, Kim JS. Development of a novel program for conversion from tetrahedral-mesh-based phantoms to DICOM dataset for radiation treatment planning: TET2DICOM. J Appl Clin Med Phys 2022; 23:e13448. [PMID: 34633736 PMCID: PMC8803294 DOI: 10.1002/acm2.13448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/22/2021] [Accepted: 09/25/2021] [Indexed: 11/11/2022] Open
Abstract
PURPOSE Tetrahedral mesh (TM)-based computational human phantoms have recently been developed for evaluation of exposure dose with the merit of precisely representing human anatomy and the changing posture freely. However, conversion of recently developed TM phantoms to the Digital Imaging and Communications in Medicine (DICOM) file format, which can be utilized in the clinic, has not been attempted. The aim of this study was to develop a technique, called TET2DICOM, to convert the TM phantoms to DICOM datasets for accurate treatment planning. MATERIALS AND METHODS The TM phantoms were sampled in voxel form to generate the DICOM computed tomography images. The DICOM-radiotherapy structure was defined based on the contour data. To evaluate TET2DICOM, the shape distortion of the TM phantoms during the conversion process was assessed, and the converted DICOM dataset was implemented in a commercial treatment planning system (TPS). RESULTS The volume difference between the TM phantoms and the converted DICOM dataset was evaluated as less than about 0.1% in each organ. Subsequently, the converted DICOM dataset was successfully implemented in MIM (MIM Software Inc., Cleveland, USA, version 6.5.6) and RayStation (RaySearch Laboratories, Stockholm, Sweden, version 5.0). Additionally, the various possibilities of clinical application of the program were confirmed using a deformed TM phantom in various postures. CONCLUSION In conclusion, the TM phantom, currently the most advanced computational phantom, can be implemented in a commercial TPS and this technique can enable various TM-based applications, such as evaluation of secondary cancer risk in radiotherapy.
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Affiliation(s)
- Bo‐Wi Cheon
- Department of Radiation Convergence EngineeringYonsei UniversityWonjuKorea
| | - Se Hyung Lee
- Department of Nuclear EngineeringHanyang UniversitySeoulKorea
- Department of Radiation OncologyBundang Jesaeng General HospitalSeongnamKorea
| | - Min Cheol Han
- Department of Radiation OncologyYonsei University College of MedicineSeoulKorea
| | - Chul Hee Min
- Department of Radiation Convergence EngineeringYonsei UniversityWonjuKorea
| | - Haegin Han
- Department of Nuclear EngineeringHanyang UniversitySeoulKorea
| | - Chan Hyeong Kim
- Department of Nuclear EngineeringHanyang UniversitySeoulKorea
| | - Jin Sung Kim
- Department of Radiation OncologyYonsei University College of MedicineSeoulKorea
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Kollitz E, Han H, Kim CH, Pinto M, Schwarz M, Riboldi M, Kamp F, Belka C, Newhauser WD, Dedes G, Parodi K. A patient-specific hybrid phantom for calculating radiation dose and equivalent dose to the whole body. Phys Med Biol 2021; 67. [PMID: 34969024 DOI: 10.1088/1361-6560/ac4738] [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: 09/28/2021] [Accepted: 12/30/2021] [Indexed: 11/12/2022]
Abstract
OBJECTIVE As cancer survivorship increases, there is growing interest in minimizing the late effects of radiation therapy such as radiogenic second cancer, which may occur anywhere in the body. Assessing the risk of late effects requires knowledge of the dose distribution throughout the whole body, including regions far from the treatment field, beyond the typical anatomical extent of clinical CT scans. APPROACH A hybrid phantom was developed which consists of in-field patient CT images extracted from ground truth whole-body CT (WBCT) scans, out-of-field mesh phantoms scaled to basic patient measurements, and a blended transition region. Four of these hybrid phantoms were created, representing male and female patients receiving proton therapy treatment in pelvic and cranial sites. To assess the performance of the hybrid approach, we simulated treatments using the hybrid phantoms, the scaled and unscaled mesh phantoms, and the ground truth whole-body CTs. We calculated absorbed dose and equivalent dose in and outside of the treatment field, with a focus on neutrons induced in the patient by proton therapy. Proton and neutron dose was calculated using a general purpose Monte Carlo code. MAIN RESULTS The hybrid phantom provided equal or superior accuracy in calculated organ dose and equivalent dose values relative to those obtained using the mesh phantoms in 78% in all selected organs and calculated dose quantities. Comparatively the default mesh and scaled mesh were equal or superior to the other phantoms in 21% and 28% of cases respectively. SIGNIFICANCE The proposed methodology for hybrid synthesis provides a tool for whole-body organ dose estimation for individual patients without requiring CT scans of their entire body. Such a capability would be useful for personalized assessment of late effects and risk-optimization of treatment plans.
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Affiliation(s)
- Erika Kollitz
- Department of Medical Physics, Ludwig-Maximilians-Universitat Munchen, Ludwig-Maximilians-Universität München, Department for Medical Physics (LS Parodi), Am Coulombwall 1, Garching, Bayern, 85748, GERMANY
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seongdong-gu, Seoul, 04763, Korea (the Republic of)
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seongdong-gu, Seoul, 04763, Korea (the Republic of)
| | - Marco Pinto
- Ludwig-Maximilians-Universitat Munchen, Ludwig-Maximilians-Universität München, Department for Medical Physics (LS Parodi), Am Coulombwall 1, Garching, Bayern, 85748, GERMANY
| | - Marco Schwarz
- Provincia autonoma di Trento Azienda Provinciale per i Servizi Sanitari, Via Alcide Degasperi 79, Trento, Trentino-Alto Adige, 38123, ITALY
| | - Marco Riboldi
- Department of Medical Physics, Ludwig-Maximilians-Universitat Munchen, Ludwig-Maximilians-Universität München, Department for Medical Physics (LS Parodi), Am Coulombwall 1, Munchen, Bayern, 85748, GERMANY
| | - Florian Kamp
- Radiotherapy, Klinikum der Universitat Munchen, Marchioninistraße 15, Munich, 81377, GERMANY
| | - Claus Belka
- Department of Radiation Oncology, Klinikum der Universitat Munchen, Marchioninistraße 15, Munchen, Bayern, 81377, GERMANY
| | - Wayne David Newhauser
- Department of Physics & Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana, 70803, UNITED STATES
| | - Georgios Dedes
- Department of Medical Physics, Ludwig-Maximilians-Universitat Munchen, Ludwig-Maximilians-Universität München, Department for Medical Physics (LS Parodi), Am Coulombwall 1, Munchen, Bayern, 85748, GERMANY
| | - Katia Parodi
- Experimental Physics Medical Physics, Ludwig-Maximilians-Universitat Munchen, Ludwig-Maximilians-Universität München, Department for Medical Physics (LS Parodi), Am Coulombwall 1, Munchen, Bayern, 85748, GERMANY
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Choi C, Shin B, Yeom YS, Nguyen TT, Han H, Ha S, Chung BS, Bolch WE, Kim CH. Development of paediatric mesh-type reference computational phantom series of International Commission on Radiological Protection. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:S160-S170. [PMID: 34082408 DOI: 10.1088/1361-6498/ac0801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/03/2021] [Indexed: 06/12/2023]
Abstract
Very recently, Task Group 103 of the International Commission on Radiological Protection (ICRP) completed the development of the paediatric mesh-type reference computational phantoms (MRCPs) comprising ten phantoms (newborn, one year-old, five year-old, ten year-old, and fifteen year-old males and females). The paediatric MRCPs address the limitations of ICRPPublication 143's paediatric reference computational phantoms, which are in voxel format, stemming from the nature of the voxel geometry and the limited voxel resolutions. The paediatric MRCPs were constructed by converting the voxel-type reference phantoms to a high-quality mesh format with substantial enhancements in the detailed anatomy of the small and complex organs and tissues (e.g. bones, lymphatic nodes, and extra-thoracic region). Besides, the paediatric MRCPs were developed in consideration of the intra-organ blood contents and by modelling the micron-thick target and source regions of the skin, lens, urinary bladder, alimentary tract organs, and respiratory tract organs prescribed by the ICRP. For external idealised exposures, the paediatric MRCPs provide very similar effective dose coefficients (DCEs) to those from the ICRP-143 phantoms but significantly different values for weakly penetrating radiations (e.g. the difference of ∼20 000 times for 10 keV electron beams). This paper introduces the developed paediatric MRCPs with a brief explanation of the construction process. Then, it discusses their computational performance in Geant4, PHITS, and MCNP6 in terms of memory usage and computation speed and their impact on dose calculations by comparing their calculated values of DCEs for external exposures with those of the voxel-type reference phantoms.
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Affiliation(s)
- Chansoo Choi
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Bangho Shin
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Yeon Soo Yeom
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, MD, United States of America
| | - Thang Tat Nguyen
- Department of Nuclear Engineering and Environmental Physics, Hanoi University of Science and Technology, Hanoi, Vietnam
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sangseok Ha
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Beom Sun Chung
- Department of Anatomy, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Wesley E Bolch
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
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Choi C, Shin B, Yeom YS, Han H, Ha S, Moon S, Son G, Nguyen TT, Kim CH, Chung BS, Bolch WE. Development of skeletal systems for ICRP pediatric mesh-type reference computational phantoms. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:139-161. [PMID: 33401263 DOI: 10.1088/1361-6498/abd88d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
In 2016, the International Commission on Radiological Protection (ICRP) launched Task Group 103 (TG 103) for the explicit purpose of developing a new generation of adult and pediatric reference computational phantoms, named 'mesh-type reference computational phantoms (MRCPs)', that can overcome the limitations of voxel-type reference computational phantoms (VRCPs) of ICRPPublications 110and143due to their finite voxel resolutions and the nature of voxel geometry. After completing the development of the adult MRCPs, TG 103 has started the development of pediatric MRCPs comprising 10 phantoms (male and female versions of the reference newborn, 1-year-old, 5-year-old, 10-year-old, and 15-year-old). As part of the TG 103 project, within the present study, the skeletal systems, one of the most important and complex organ systems of the body, were developed for each phantom age and sex. The developed skeletal systems, while closely preserving the original bone topology of the pediatric VRCPs, present substantial improvements in the anatomy of complex and/or small bones. In order to investigate the dosimetric impact of the developed skeletons, the average absorbed doses and the specific absorbed fractions for radiosensitive skeletal tissues (i.e. active marrow and bone endosteum) were computed for some selected external and internal exposure cases, which were then compared with those calculated with the skeletons of pediatric VRCPs. The comparison result showed that the dose values of the pediatric MRCPs were generally similar to those of the pediatric VRCPs for highly penetrating radiations (e.g. photons >200 keV); however, for weakly penetrating radiations (e.g. photons ⩽200 keV and electrons), significant differences up to a factor of 140 were observed.
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Affiliation(s)
- Chansoo Choi
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Bangho Shin
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Yeon Soo Yeom
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States of America
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sangseok Ha
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sungho Moon
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Gahee Son
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Thang Tat Nguyen
- School of Nuclear Engineering and Environmental Physics, Hanoi University of Science and Technology, Hanoi, Vietnam
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Beom Sun Chung
- Department of Anatomy, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Wesley E Bolch
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
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Yeom YS, Griffin K, Shin B, Choi C, Han H, Moon S. Body-size-dependent Iodine-131 Svalues. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2020; 40:1311-1320. [PMID: 33045695 DOI: 10.1088/1361-6498/abc053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/12/2020] [Indexed: 06/11/2023]
Abstract
In a recent epidemiologic risk assessment on late health effects of patients treated with radioactive iodine (RAI), organ/tissue doses of the patients were estimated based on iodine-131Svalues derived from the reference computational phantoms of the International Commission on Radiological Protection (ICRP). However, the use of theSvalues based on the reference phantoms may lead to significant biases in the estimated doses of patients whose body sizes (height and weight) are significantly different from the reference body sizes. To fill this critical gap, we established a comprehensive dataset of body-size-dependent iodine-131Svalues (rT← thyroid) for 30 radiosensitive target organs/tissues by performing Monte Carlo dose calculations coupled with a total of 212 adult male and female computational phantoms in different heights and weights. We observed that theSvalues tend to decrease with increasing body height; for example, theSvalue (gonads ← thyroid) of the 160 cm male phantom is about 3 times higher than that of the 190 cm male phantom at the 70 kg weight. We also observed that theSvalues tend to decrease with increasing body weight for some organs/tissues; for example, theSvalue (skin ← thyroid) of the 45 kg female phantom is about two times higher than that of the 130 kg female phantom at the 160 cm height. For other organs/tissues, which are relatively far from the thyroid, in contrast, theSvalues tend to increase with increasing body weight; for example, theSvalue (bladder ← thyroid) of the 45 kg female phantom is about 2 times lower than that of the 130 kg female phantom. Overall, the majority of the body-size-dependentSvalues deviated to within 25% from those of the reference phantoms. We believe that the use of body-size-dependentSvalues in dose reconstructions should help quantify the dosimetric uncertainty in epidemiologic investigations of RAI-treated patients.
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Affiliation(s)
- Yeon Soo Yeom
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20850, United States of America
| | - Keith Griffin
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20850, United States of America
| | - Bangho Shin
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Chansoo Choi
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Haegin Han
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sungho Moon
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
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