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Currie GM, Rohren EM. Radiation Dosimetry, Artificial Intelligence and Digital Twins: Old Dog, New Tricks. Semin Nucl Med 2023; 53:457-466. [PMID: 36379728 DOI: 10.1053/j.semnuclmed.2022.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 11/14/2022]
Abstract
Developments in artificial intelligence, particularly convolutional neural networks and deep learning, have the potential for problem solving that has previously confounded human intelligence. Accurate prediction of radiation dosimetry pre-treatment with scope to adjust dosing for optimal target and non-target tissue doses is consistent with striving for improved the outcomes of precision medicine. The combination of artificial intelligence and production of digital twins could provide an avenue for an individualised therapy doses and enhanced outcomes in theranostics. While there are barriers to overcome, the maturity of individual technologies (i.e. radiation dosimetry, artificial intelligence, theranostics and digital twins) places these approaches within reach.
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Affiliation(s)
- Geoffrey M Currie
- Charles Sturt University, NSW, Australia; Baylor College of Medicine, TX.
| | - Eric M Rohren
- Charles Sturt University, NSW, Australia; Baylor College of Medicine, TX
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Fatima Z, Ali N, Williams MA, Dhar S, Maqbool M. X-ray scattering and attenuation cross-sections and coefficients of bone, brain, lung, fat, and soft tissue for applications in dosimetry, cancer detection, and treatment. Radiat Phys Chem Oxf Engl 1993 2023. [DOI: 10.1016/j.radphyschem.2023.110908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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Amraee N, Alirezapour B, Hosntalab M, Yousefnia H. Human Dose Assessment of 68Ga-NODAGA-RGD-BBN Heterodimer Peptide based on Animal Data. J Med Phys 2022; 47:287-293. [PMID: 36684706 PMCID: PMC9847008 DOI: 10.4103/jmp.jmp_34_22] [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: 05/01/2022] [Revised: 08/04/2022] [Accepted: 08/17/2022] [Indexed: 11/10/2022] Open
Abstract
Aims Calculation of the absorbed dose in human organs is one of the first steps for developing new radiopharmaceuticals. The aim of this study is to estimate the human absorbed dose of a newly developed 68Ga-NODAGA-RGD-BBN radiolabeled compound. Materials and Methods 68Ga-NODAGA-RGD-BBN was prepared by varying different parameters at optimized conditions. The stability of the radiolabeled peptide in phosphate-buffered saline (PBS) and in human serum was evaluated for 120 min. Afterward, the biodistribution of the complex was assessed in normal and tumor-bearing mice, at least for 120 min postinjection. Finally, the human absorbed dose of 68Ga-NODAGA-RGD-BBN was estimated based on mice data using Radiation Dose Assessment Resource and Spark method. Results 68Ga-NODAGA-RGD-BBN was produced with radiochemical purity of more than 98% (high-performance liquid chromatography/ radio thin layer chromatography (RTLC)) with high stability in PBS buffer and in human serum at least for 2 h. The complex demonstrated high uptake in gastrin-releasing peptide receptor-expressing tumors compared to other nontarget organs. Furthermore, the dose assessment for the complex showed that the kidneys receive the highest absorbed dose in comparison with other organs. Conclusion The result of this study showed that 68Ga-NODAGA-RGD-BBN is an effective and radiolabeled ligand for tumor detection, however more studies are still needed.
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Affiliation(s)
- Naeimeh Amraee
- Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University (IAU), Tehran, Iran
| | - Behrouz Alirezapour
- Department of Radioisotope and Radiopharmaceutical Research, Radiation Application Research School, Nuclear Science and Technology, Research Institute, Tehran, Iran
| | - Mohammad Hosntalab
- Department of Medical Radiation Engineering, Science and Research Branch, Islamic Azad University (IAU), Tehran, Iran
| | - Hassan Yousefnia
- Department of Radioisotope and Radiopharmaceutical Research, Radiation Application Research School, Nuclear Science and Technology, Research Institute, Tehran, Iran
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Alirezapour B, Yousefnia H, Zolghadri S. Human absorbed dose estimation of 111In-DOTA-PR81 as a novel high potential agent for breast cancer imaging. J Med Phys 2022; 47:194-200. [PMID: 36212201 PMCID: PMC9542994 DOI: 10.4103/jmp.jmp_72_21] [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: 05/17/2021] [Revised: 02/01/2022] [Accepted: 02/08/2022] [Indexed: 11/17/2022] Open
Abstract
Purpose: In this study, the human absorbed dose of 111In-DOTA-PR81 as a new radioimmunoconjugate for single-photon emission computed tomography (SPECT) imaging of MUC1 + breast cancer was determined. Materials and Methods: The complex was prepared at optimized conditions in about 1 h and 38°C. The radiochemical purity of the tracer was investigated using the instant thin-layer chromatography method method, showing purity of higher than 96%. After evaluating the stability of the product in human serum and room temperature, the biological distribution of the radiolabeled compound was studied in normal rats and tumor-bearing mice. Finally, the human absorbed dose of the complex was estimated based on animals’ data using radiation dose assessment resource and Spark et al. methods. Results: High uptake of the complex in MUC1 + breast tumors compared to other nontarget organs shows that the radioimmunoconjugate is a beneficial agent for SPECT imaging of MUC1 + breast cancer. Human organs absorbed dose estimation of the complex demonstrated the highest amounts of the absorbed dose are in the liver and kidneys with 0.384 and 0.245 mGy/MBq, respectively. Conclusions: 111In-DOTA-PR81 radioimmunoconjugate is a high potential agent for MUC1 + breast cancer SPECT imaging and estimated absorbed dose values could helpfully use for the determination of the maximum injectable dose.
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Hu P, Lin X, Zhuo W, Tan H, Xie T, Liu G, Chen S, Chen X, Yu H, Zhang Y, Shi H, Liu H. Internal dosimetry in F-18 FDG PET examinations based on long-time-measured organ activities using total-body PET/CT: does it make any difference from a short-time measurement? EJNMMI Phys 2021; 8:51. [PMID: 34264416 PMCID: PMC8282883 DOI: 10.1186/s40658-021-00395-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 06/21/2021] [Indexed: 11/10/2022] Open
Abstract
PURPOSE A 2-m axial field-of-view, total-body PET/CT scanner (uEXPLORER) has been recently developed to provide total-body coverage and ultra-high sensitivity, which together, enables opportunities for in vivo time-activity curve (TAC) measurement of all investigated organs simultaneously with high temporal resolution. This study aims at quantifying the cumulated activity and patient dose of 2-[F-18]fluoro-2-deoxy-D-glucose (F-18 FDG ) imaging by using delayed time-activity curves (TACs), measured out to 8-h post-injection, for different organs so that the comparison between quantifying approaches using short-time method (up to 75 min post-injection) or long-time method (up to 8 h post-injection) could be performed. METHODS Organ TACs of 10 healthy volunteers were collected using total-body PET/CT in 4 periods after the intravenous injection of F-18 FDG. The 8-h post-injection TACs of 6 source organs were fitted using a spline method (based on Origin (version 8.1)). To compare with cumulated activity estimated from spline-fitted curves, the cumulated activity estimated from multi-exponential curve was also calculated. Exponential curve was fitted with shorter series of data consistent with clinical procedure and previous dosimetry works. An 8-h dynamic bladder wall dose model considering 2 voiding were employed to illustrate the differences in bladder wall dose caused by the different measurement durations. Organ absorbed doses were further estimated using Medical Internal Radiation Dose (MIRD) method and voxel phantoms. RESULTS A short-time measurement could lead to significant bias in estimated cumulated activity for liver compared with long-time-measured spline fitted method, and the differences of cumulated activity were 18.38% on average. For the myocardium, the estimated cumulated activity difference was not statistically significant due to large variation in metabolism among individuals. The average residence time differences of brain, heart, kidney, liver, and lungs were 8.38%, 15.13%, 25.02%, 23.94%, and 16.50% between short-time and long-time methods. Regarding effective dose, the maximum differences of residence time between long-time-measured spline fitted curve and short-time-measured multi-exponential fitted curve was 9.93%. When using spline method, the bladder revealed the most difference in the effective dose among all the investigated organs with a bias up to 21.18%. The bladder wall dose calculated using a long-time dynamic model was 13.79% larger than the two-voiding dynamic model, and at least 50.17% lower than previous studies based on fixed bladder content volume. CONCLUSIONS Long-time measurement of multi-organ TACs with high temporal resolution enabled by a total-body PET/CT demonstrated that the clinical procedure with 20 min PET scan at 1 h after injection could be used for retrospective dosimetry analysis in most organs. As the bladder content contributed the most to the effective dose, a long-time dynamic model was recommended for the bladder wall dose estimation.
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Affiliation(s)
- Pengcheng Hu
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Xin Lin
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China
| | - Weihai Zhuo
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China
| | - Hui Tan
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Tianwu Xie
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China
| | - Guobing Liu
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Shuguang Chen
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Xin Chen
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China
| | - Haojun Yu
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Yiqiu Zhang
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China
| | - Hongcheng Shi
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 1069 Xietu Road, Shanghai, 200032, China.
| | - Haikuan Liu
- Institute of Radiation Medicine, Fudan University, 2094 Xietu Road, Shanghai, 200032, China.
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Jiao D, Yao Y, Xu K, Lei Q, Li Z, Han X, Ren J. Investigation of a novel brachytherapy ureteral stent: trial studies on normal beagle dogs. J Cancer Res Clin Oncol 2021; 147:1115-1123. [PMID: 33492493 DOI: 10.1007/s00432-021-03513-w] [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] [Received: 10/14/2020] [Accepted: 01/09/2021] [Indexed: 10/22/2022]
Abstract
PURPOSE To evaluate the safety and feasibility of a newly designed 125I brachytherapy ureteral stent (BUS) in normal dogs. METHODS A BUS loaded with 10 125I seeds (Group A: 0.8 mCi, Group B: 0.4 mCi, Group C: 0 mCi) was designed and tested in 27 normal beagle dogs. Routine blood tests, gross observations, cumulative radiation doses, tissue reaction assessed by hematoxylin-eosin/Masson staining, mRNA analysis by RT-qPCR and protein expression of Caspase-3, Collagen I, PCNA, and α-SMA were performed at 2, 4 and 8 weeks. RESULTS The BUS was implanted successfully in all dogs (27/27) without surgery-related death. The ureter diameter and radiation injury score increased along with radiation accumulation (p < 0.05). Histopathologic analysis showed necrotic tissue and lateral fibrosis to different extents in the ureteral walls that gradually increased in all groups (p < 0.05); however, epithelial cell proliferation in groups A and B was lighter than that in the control group (p < 0.05). CONCLUSION Placement of the newly designed 125I BUS was safe and feasible in dogs, and clinical studies are required to test its use in humans.
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Affiliation(s)
- Dechao Jiao
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China
| | - Yuan Yao
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China.,Academy of Medical Sciences, Zhengzhou University, Zhengzhou, 450052, Henan, People's Republic of China
| | - Kaihao Xu
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China
| | - Qinyu Lei
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China
| | - Zongming Li
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China
| | - Xinwei Han
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China. .,Academy of Medical Sciences, Zhengzhou University, Zhengzhou, 450052, Henan, People's Republic of China.
| | - Jianzhuang Ren
- Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 1 Jianshe Road, Zhengzhou, 450052, Henan, People's Republic of China.
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A S, F H, M M. Determination of Uterus Absorbed Dose by Patients following Myocardial Perfusion Scan using TLD and Conjugate View Methods. J Biomed Phys Eng 2019; 9:445-452. [PMID: 31531297 PMCID: PMC6709359 DOI: 10.31661/jbpe.v0i0.574] [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: 05/13/2016] [Accepted: 08/27/2016] [Indexed: 06/10/2023]
Abstract
INTRODUCTION The determination of patient's absorbed dose is the first step of radiation protection which depends on the quantification of organ activity in nuclear medicine. The aim of the present study was to determine the absorbed dose by patient's uterus following myocardial perfusion scan with 99mTC-sestamibi using Theroluminescnce dosimetry (TLD) and conjugate-view methods. MATERIAL AND METHOD In this study, each patient was injected 15 to 20 mCi (based on their weight) of 99mTC-sestamibi. Myocardial perfusion scan from twenty two patients (females) were acquired by gamma camera at 15, 60 and 90 minutes after 99mTC-sestamibi injection. To determine the amount of activity in uterus, conjugate view method was applied on images. Then, MIRD equation was used to estimate absorbed dose in uterus of patients. Moreover, uterus absorbed dose was determined using TLD method. At the end, absorbed dose values obtained in conjugate view method were compared with the data obtained from TLD method. RESULTS The average amount of uptake for 99mTC-sestamibi by heart was calculated 3.077±0.067 percent of injected dose. The uterus activity at the intervals of 15, 60 and 90 minutes after injection of 99mTC-sestamibi was 0.044±0.015, 0.031±0.014 and 0.026±0.013 mCi, repectively. The uterus absorbed dose per unit of injected activity (mGy/MBq × 10-4) obtained 5.258±0.500 using TLD method. CONCLUSION The results of this study were in good agreement with similar studies. Dosimetry using TLD, in comparison with the conjugate view method, demonstrates more accurate results.
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Affiliation(s)
- Shanei A
- Associate Professor, Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Heydari F
- MSc, Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Moslehi M
- Assistant Professor, Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Huang YY, Chiu MJ, Yen RF, Tsai CL, Hsieh HY, Chiu CH, Wu CH, Hsin LW, Tzen KY, Cheng CY, Ma KH, Shiue CY. An one-pot two-step automated synthesis of [18F]T807 injection, its biodistribution in mice and monkeys, and a preliminary study in humans. PLoS One 2019; 14:e0217384. [PMID: 31260447 PMCID: PMC6602418 DOI: 10.1371/journal.pone.0217384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/11/2019] [Indexed: 12/22/2022] Open
Abstract
[18F]T807 is a potent tau protein imaging agent. In order to fulfill the demand from preclinical and clinical studies, we developed an automated one-pot two-step synthesis of this potent tau imaging agent and studied its stability, and dosimetry in mice and monkeys. We also conducted a preliminary study of this imaging agent in humans. Using this one-pot two-step method, the radiochemical yield (RCY) of [18F]T807 was 20.5 ± 6.1% (n = 15) at the end of bombardment (EOB) in a synthesis time of 70±5 min. The chemical and radiochemical purities were >90% and the specific activities were 151 ± 52 GBq/μmol. The quality of [18F]T807 synthesized by this method met the U.S. Pharmacopoeia (USP) criteria. The stability test showed that the [18F]T807 injection was stable at room temperature for up to 4 h after the end of synthesis (EOS). The estimated effective dose of the [18F]T807 injection extrapolated from monkeys was 19 μSv/MBq (n = 2), while the estimated effective doses of the [18F]T807 injection extrapolated from fasted and non-fasted mice were 123 ± 27 (n = 3) and 94 ± 19 (n = 4) μSv/MBq, respectively. This one-pot two-step automated method produced the [18F]T807 injection with high reproducibility and high quality. PET imaging and radiation dosimetry evaluation in mice and Formosan rock monkeys suggested that the [18F]T807 injection synthesized by this method is suitable for use in human PET imaging studies. Thus, this method could fulfill the demand for the [18F]T807 injection in both preclinical and clinical studies of tauopathies, especially for nearby study sites without cyclotrons.
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Affiliation(s)
- Ya-Yao Huang
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Ming-Jang Chiu
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
- Departments of Neurology, National Taiwan University Hospital, Taipei, Taiwan
- Institute of Brain and Mind Sciences, College of Medicine, National Taiwan University, Zhongzheng Dist., Taipei, Taiwan
- Department of Psychology, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Biomedical Engineering and Bio-informatics, National Taiwan University, Taipei, Taiwan
| | - Ruoh-Fang Yen
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
- Department of Radiology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Chia-Ling Tsai
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Hao-Yu Hsieh
- School of Pharmacy, College of Medicine, National Taiwan University, Zhongzheng Dist., Taipei, Taiwan
| | - Ching-Hung Chiu
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Chi-Han Wu
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Ling-Wei Hsin
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
- School of Pharmacy, College of Medicine, National Taiwan University, Zhongzheng Dist., Taipei, Taiwan
| | - Kai-Yuan Tzen
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
| | - Cheng-Yi Cheng
- PET Center, Department of Nuclear Medicine, Tri-Service General Hospital, Neihu, Taipei, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Chyng-Yann Shiue
- PET Center, Department of Nuclear Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Molecular Imaging Center, National Taiwan University, Taipei, Taiwan
- PET Center, Department of Nuclear Medicine, Tri-Service General Hospital, Neihu, Taipei, Taiwan
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Factors affecting accuracy of S values and determination of time-integrated activity in clinical Lu-177 dosimetry. Ann Nucl Med 2019; 33:521-531. [DOI: 10.1007/s12149-019-01365-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/16/2019] [Indexed: 12/20/2022]
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Wevrett J, Fenwick A, Scuffham J, Johansson L, Gear J, Schlögl S, Segbers M, Sjögreen-Gleisner K, Solný P, Lassmann M, Tipping J, Nisbet A. Inter-comparison of quantitative imaging of lutetium-177 ( 177Lu) in European hospitals. EJNMMI Phys 2018; 5:17. [PMID: 30069805 PMCID: PMC6070453 DOI: 10.1186/s40658-018-0213-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 04/13/2018] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND This inter-comparison exercise was performed to demonstrate the variability of quantitative SPECT/CT imaging for lutetium-177 (177Lu) in current clinical practice. Our aim was to assess the feasibility of using international inter-comparison exercises as a means to ensure consistency between clinical sites whilst enabling the sites to use their own choice of quantitative imaging protocols, specific to their systems. Dual-compartment concentric spherical sources of accurately known activity concentrations were prepared and sent to seven European clinical sites. The site staff were not aware of the true volumes or activity within the sources-they performed SPECT/CT imaging of the source, positioned within a water-filled phantom, using their own choice of parameters and reported their estimate of the activities within the source. RESULTS The volumes reported by the participants for the inner section of the source were all within 29% of the true value and within 60% of the true value for the outer section. The activities reported by the participants for the inner section of the source were all within 20% of the true value, whilst those reported for the outer section were up to 83% different to the true value. CONCLUSIONS A variety of calibration and segmentation methods were used by the participants for this exercise which demonstrated the variability of quantitative imaging across clinical sites. This paper presents a method to assess consistency between sites using different calibration and segmentation methods.
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Affiliation(s)
- Jill Wevrett
- University of Surrey, Guildford, UK.
- National Physical Laboratory, Teddington, UK.
- Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK.
| | | | - James Scuffham
- University of Surrey, Guildford, UK
- Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK
| | | | | | | | - Marcel Segbers
- Erasmus University Medical Centre, Rotterdam, Netherlands
| | | | - Pavel Solný
- Motol University Hospital, Prague, Czech Republic
| | | | - Jill Tipping
- The Christie NHS Foundation Trust, Manchester, UK
| | - Andrew Nisbet
- University of Surrey, Guildford, UK
- Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK
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Josefsson A, Hobbs RF, Ranka S, Schwarz BC, Plyku D, Willegaignon de Amorim de Carvalho J, Buchpiguel CA, Sapienza MT, Bolch WE, Sgouros G. Comparative Dosimetry for 68Ga-DOTATATE: Impact of Using Updated ICRP Phantoms, S Values, and Tissue-Weighting Factors. J Nucl Med 2018; 59:1281-1288. [PMID: 29439017 PMCID: PMC6071503 DOI: 10.2967/jnumed.117.203893] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 12/14/2017] [Indexed: 01/21/2023] Open
Abstract
The data that have been used in almost all calculations of MIRD S value absorbed dose and effective dose are based on stylized anatomic computational phantoms and tissue-weighting factors adopted by the International Commission on Radiological Protection (ICRP) in its publication 60. The more anatomically realistic phantoms that have recently become available are likely to provide more accurate effective doses for diagnostic agents. 68Ga-DOTATATE is a radiolabeled somatostatin analog that binds with high affinity to somatostatin receptors, which are overexpressed in neuroendocrine tumors and can be used for diagnostic PET/CT-based imaging. Several studies have reported effective doses for 68Ga-DOTATATE using the stylized Cristy-Eckerman (CE) phantoms from 1987; here, we present effective dose calculations using both the ICRP 60 and more updated formalisms. Methods: Whole-body PET/CT scans were acquired for 16 patients after 68Ga-DOTATATE administration. Contours were drawn on the CT images for spleen, liver, kidneys, adrenal glands, brain, heart, lungs, thyroid gland, salivary glands, testes, red marrow (L1-L5), muscle (right thigh), and whole body. Dosimetric calculations were based on the CE phantoms and the more recent ICRP 110 reference-voxel phantoms. Tissue-weighting factors from ICRP 60 and ICRP 103 were used in effective dose calculations for the CE phantoms and ICRP 110 phantoms, respectively. Results: The highest absorbed dose coefficients (absorbed dose per unit activity) were, in descending order, in the spleen, pituitary gland, kidneys, adrenal glands, and liver. For ICRP 110 phantoms with tissue-weighting factors from ICRP 103, the effective dose coefficient was 0.023 ± 0.003 mSv/MBq, which was significantly lower than the 0.027 ± 0.005 mSv/MBq calculated for CE phantoms with tissue-weighting factors from ICRP 60. One of the largest differences in estimated absorbed dose coefficients was for the urinary bladder wall, at 0.040 ± 0.011 mGy/MBq for ICRP 110 phantoms compared with 0.090 ± 0.032 mGy/MBq for CE phantoms. Conclusion: This study showed that the effective dose coefficient was slightly overestimated for CE phantoms, compared with ICRP 110 phantoms using the latest tissue-weighting factors from ICRP 103. The more detailed handling of electron transport in the latest phantom calculations gives significant differences in estimates of the absorbed dose to stem cells in the walled organs of the alimentary tract.
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Affiliation(s)
- Anders Josefsson
- Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore Maryland
| | - Robert F Hobbs
- Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore Maryland
- Department of Radiation Oncology, School of Medicine, Johns Hopkins University, Baltimore Maryland
| | - Sagar Ranka
- Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore Maryland
| | - Bryan C Schwarz
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida; and
| | - Donika Plyku
- Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore Maryland
| | | | - Carlos Alberto Buchpiguel
- Instituto do Cancer do Estado de São Paulo, School of Medicine, São Paulo University, São Paulo, Brazil
| | - Marcelo Tatit Sapienza
- Instituto do Cancer do Estado de São Paulo, School of Medicine, São Paulo University, São Paulo, Brazil
| | - Wesley E Bolch
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida; and
| | - George Sgouros
- Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore Maryland
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Absorbed doses in humans from 188 Re-Rituximab in the free form and bound to superparamagnetic iron oxide nanoparticles: Biodistribution study in mice. Appl Radiat Isot 2018; 131:96-102. [DOI: 10.1016/j.apradiso.2017.10.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 10/12/2017] [Accepted: 10/23/2017] [Indexed: 11/18/2022]
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Sudbrock F, Schomäcker K, Drzezga A. The effectiveness of wastewater treatment in nuclear medicine: Performance data and radioecological considerations. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 166:202-207. [PMID: 27094379 DOI: 10.1016/j.jenvrad.2016.04.002] [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: 10/29/2015] [Revised: 03/10/2016] [Accepted: 04/03/2016] [Indexed: 06/05/2023]
Abstract
For planned and ongoing storage of liquid radioactive waste in a designated plant for a nuclear medicine therapy ward (decontamination system/decay system), detailed knowledge of basic parameters such as the amount of radioactivity and the necessary decay time in the plant is required. The design of the plant at the Department of Nuclear Medicine of the University of Cologne, built in 2001, was based on assumptions about the individual discharge of activity from patients, which we can now retrospectively validate. The decontamination factor of the plant is at present in the order of 10-9 for 131I. The annual discharges have been continuously reduced over the period of operation and are now in the region of a few kilobecquerels. This work emphasizes the high efficacy of the decontamination plant to reduce the amount of radioactivity released from the nuclear medicine ward into the environment to almost negligible levels.
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Affiliation(s)
- F Sudbrock
- Department of Nuclear Medicine, University Hospital of Cologne, Germany.
| | - K Schomäcker
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
| | - A Drzezga
- Department of Nuclear Medicine, University Hospital of Cologne, Germany
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Vaez-Tehrani M, Zolghadri S, Yousefnia H, Afarideh H. Estimation of human absorbed dose for (166)Ho-PAM: comparison with (166)Ho-DOTMP and (166)Ho-TTHMP. Br J Radiol 2016; 89:20160153. [PMID: 27524266 DOI: 10.1259/bjr.20160153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
OBJECTIVE In this study, the human absorbed dose of holmium-166 ((166)Ho)-pamidronate (PAM) as a potential agent for the management of multiple myeloma was estimated. METHODS (166)Ho-PAM complex was prepared at optimized conditions and injected into the rats. The equivalent and effective absorbed doses to human organs after injection of the complex were estimated by radiation-absorbed dose assessment resource and methods proposed by Sparks et al based on rat data. The red marrow to other organ absorbed dose ratios were compared with these data for (166)Ho-DOTMP, as the only clinically used (166)Ho bone marrow ablative agent, and (166)Ho-TTHMP. RESULTS The highest absorbed dose amounts are observed in the bone surface and bone marrow with 1.11 and 0.903 mGy MBq(-1), respectively. Most other organs would receive approximately insignificant absorbed dose. While (166)Ho-PAM demonstrated a higher red marrow to total body absorbed dose ratio than (166)Ho-1,4,7,10-tetraazacyclo dodecane-1,4,7,10 tetra ethylene phosphonic acid (DOTMP) and (166)Ho-triethylene tetramine hexa (methylene phosphonic acid) (TTHMP), the red marrow to most organ absorbed dose ratios for (166)Ho-TTHMP and (166)Ho-PAM are much higher than the ratios for (166)Ho-DOTMP. CONCLUSION The result showed that (166)Ho-PAM has significant characteristics than (166)Ho-DOTMP and therefore, this complex can be considered as a good agent for bone marrow ablative therapy. ADVANCES IN KNOWLEDGE In this work, two separate points have been investigated: (1) human absorbed dose of (166)Ho-PAM, as a potential bone marrow ablative agent, has been estimated; and (2) the complex has been compared with (166)Ho-DOTMP, as the only clinically used bone marrow ablative radiopharmaceutical, showing significant characteristics.
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Affiliation(s)
- Mahdokht Vaez-Tehrani
- 1 Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran
| | - Samaneh Zolghadri
- 2 Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran
| | - Hassan Yousefnia
- 2 Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran
| | - Hossein Afarideh
- 1 Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran
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Vaez-Tehrani M, Zolghadri S, Yousefnia H, Afarideh H. Human absorbed dose estimation for a new (175)Yb-phosphonate based on rats data: Comparison with similar bone pain palliation agents. Appl Radiat Isot 2016; 115:55-60. [PMID: 27337650 DOI: 10.1016/j.apradiso.2016.06.013] [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: 01/27/2016] [Revised: 06/07/2016] [Accepted: 06/12/2016] [Indexed: 10/21/2022]
Abstract
In this work, the absorbed dose to human organs for (175)Yb-BPAMD was evaluated based on the biodistribution studies in rats. The results showed that the bone surface would receive the highest absorbed dose after injection of (175)Yb-BPAMD with 13.32mGy/MBq, while the other organs receive insignificant absorbed dose. Also, the comparison of (175)Yb-BPAMD with other therapeutic phosphonate complexes demonstrated noticeable characteristics for this new agent. Generally, based on the obtained results, (175)Yb-BPAMD can be considered as a promising agent for bone pain palliative therapy in near future.
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Affiliation(s)
- Mahdokht Vaez-Tehrani
- Energy Engineering and Department of Physics, Amir Kabir University of Technology, Tehran, Iran
| | - Samaneh Zolghadri
- Nuclear Science and Technology Research Institute (NSTRI), 14155-1339 Tehran, Iran
| | - Hassan Yousefnia
- Nuclear Science and Technology Research Institute (NSTRI), 14155-1339 Tehran, Iran
| | - Hossein Afarideh
- Energy Engineering and Department of Physics, Amir Kabir University of Technology, Tehran, Iran
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Dosimetric analysis of 177Lu-DOTA-rituximab in patients with relapsed/refractory non-Hodgkin's lymphoma. Nucl Med Commun 2016; 37:735-42. [PMID: 26974315 DOI: 10.1097/mnm.0000000000000501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Radioimmunotherapy targeting CD20 receptors in lymphoma using radiolabeled chimeric antibodies may lead to better therapeutic responses than cold anti-CD20 antibodies. This study aimed to assess the biodistribution and present reasonable estimates of normal organ doses, including red marrow using Lu-DOTA-rituximab. MATERIALS AND METHODS Patients with relapsed/refractory CD20+ B-cell non-Hodgkin's lymphoma were recruited into this prospective study. In-house labeling of Lu-DOTA-rituximab was performed and administered after quality assurance. Rituximab (375 mg/m), followed by 50 mCi (1850 MBq) of Lu-DOTA-rituximab was administered as a slow intravenous infusion and emission images were acquired. Regions of interest were drawn for kidney, liver, heart, bladder, spleen, and tumor lesions on both anterior and posterior images. Internal dose estimation was performed using OLINDA v1.0 software. RESULTS The mean age of the 10 patients (eight men and two women) was 52±13 years. The uptake of radiolabeled antibody was visualized within 30 min of administration in the liver, kidneys, heart, spleen, and bladder. The coefficient of determination (R) was greater than 0.95 for organs and the whole body in all patients. The effective half-life of radioimmunoconjugate was 100±28 h (42-126 h). The critical organ in our study was the red marrow. The average total body dose, effective dose, and effective dose equivalent calculated in all 10 patients were 0.13±0.02, 0.15±0.03, and 0.22±0.04 mGy/MBq, respectively. CONCLUSION There may be considerable interindividual differences in absorbed doses of organs and generalization or extrapolation of doses in the clinical setting at present is not feasible with Lu-DOTA-rituximab in non-Hodgkin's lymphoma patients. Patient-specific dosimetry is thus recommended to eliminate the variations and reduce the possibility of dose-limiting toxicity.
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Estimated human absorbed dose of ¹⁷⁷Lu-BPAMD based on mice data: Comparison with ¹⁷⁷Lu-EDTMP. Appl Radiat Isot 2015; 104:128-35. [PMID: 26163291 DOI: 10.1016/j.apradiso.2015.06.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/26/2015] [Accepted: 06/29/2015] [Indexed: 11/20/2022]
Abstract
In this work, the absorbed dose of human organs for (177)Lu-BPAMD was evaluated based on biodistribution studies into the Syrian mice by RADAR method and was compared with (177)Lu-EDTMP as the only clinically used Lu-177 bone-seeking agent. The highest absorbed dose for both (177)Lu-BPAMD and (177)Lu-EDTMP is observed on the bone surface with 8.007 and 4.802 mSv/MBq. Generally, (177)Lu-BPAMD has considerable characteristics compared with (177)Lu-EDTMP and can be considered as a promising agent for the bone pain palliation therapy.
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Huang YY, Cheng CY, Huang WS, Ma KH, Tseng TW, Chou TK, Huang Y, Shiue CY. Toxicity and radiation dosimetry studies of the serotonin transporter radioligand [(18) F]AFM in rats and monkeys. EJNMMI Res 2015; 4:71. [PMID: 26116128 PMCID: PMC4452647 DOI: 10.1186/s13550-014-0071-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 11/27/2014] [Indexed: 11/12/2022] Open
Abstract
Background [18 F]AFM is a potent and promising PET imaging agent for the serotonin transporter. We carried out an acute toxicity study in rats and radiation dosimetry in monkeys before the translation of the tracer to humans. Methods Single- and multiple-dose toxicity studies were conducted in Sprague–Dawley rats. Male and female rats were injected intravenously with AFM tartrate as a single dose of 98.7 or 987 μg/kg (592 or 5,920 μg/m2, 100× or 1,000× the proposed human dose of 8 μg, respectively) on day 1 or as five consecutive daily doses of 98.7 μg/kg/day (592 μg /m2/day, 100× human dose, total dose 493.5 μg/kg). PET/CT scans were performed in four Formosan rock monkeys (two males and two females, each monkey scanned twice) using a Siemens BIOGRAPH scanner. After injection of [18 F]AFM (88.5 ± 20.3 MBq), a low-dose CT scan and a series of eight whole-body PET scans in 3-D mode were performed. Time-activity data of source organs were used to calculate the residence times and estimate the absorbed radiation dose using the OLINDA/EXM software. Results In the rats, neither the single dose nor the five daily doses of AFM tartrate produced overt adverse effects clinically. In the monkeys, the radiation doses received by most organs ranged between 8.3 and 39.1 μGy/MBq. The osteogenic cells, red marrow, and lungs received the highest doses of 39.1, 35.4, and 35.1 μGy/MBq, respectively. The effective doses extrapolated to male and female adult humans were 18.0 and 18.3 μSv/MBq, respectively. Conclusions Toxicity studies in Sprague–Dawley rats and radiation dosimetry studies in Formosa rock monkeys suggest that [18 F]AFM is safe for use in human PET imaging studies. Trial registration IACUC-12-200.
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Affiliation(s)
- Ya-Yao Huang
- PET Center, Department of Nuclear Medicine, Tri-Service General Hospital, 325 Sec. 2, Cheng-Kung Road, Taipei, 114, Taiwan,
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Yousefnia H, Zolghadri S. Estimated human absorbed dose of a new (153)Sm bone seeking agent based on biodistribution data in mice: Comparison with (153)Sm-EDTMP. Phys Med 2015; 31:714-9. [PMID: 26095757 DOI: 10.1016/j.ejmp.2015.05.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/28/2015] [Accepted: 05/26/2015] [Indexed: 11/28/2022] Open
Abstract
PURPOSE The main goal in radiotherapy is to deliver the absorbed dose within the target organs in highest possible amount, while the absorbed dose of the other organs, especially the critical organs, should be kept as low as possible. In this work, the absorbed dose to human organs for a new (153)Sm bone-seeking agent was investigated. METHODS (153)Sm-(4-{[(bis(phosphonomethyl))carbamoyl]methyl}-7,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl) acetic acid ((153)Sm-BPAMD) complex was successfully prepared. The biodistribution of the complex was investigated in male Syrian mice up to 48 h post injection. The human absorbed dose of the complex was estimated based on the biodistribution data of the mice by radiation absorbed dose assessment resource (RADAR) method. The target to non-target absorbed dose ratios for (153)Sm-BPAMD were compared with these ratios for (153)Sm-EDTMP. RESULTS The highest absorbed dose for (153)Sm-BPAMD was observed in bone surface with 5.828 mGy/MBq. The dose ratios of the bone surface to the red marrow and to the total body for (153)Sm-BPAMD were 5.3 and 20.0, respectively, while these ratios for (153)Sm-EDTMP were 4.4 and 18.3, respectively. This means, for a given dose to the bone surface as the target organ, the red marrow (as the main critical organ) and the total body would receive lesser absorbed dose in the case of (153)Sm-BPAMD. CONCLUSIONS Generally, the human absorbed dose estimation of (153)Sm-BPAMD indicated that all other tissues approximately received insignificant absorbed dose in comparison with bone surface and therefore can be regarded as a new potential agent for bone pain palliation therapy.
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Affiliation(s)
- Hassan Yousefnia
- Nuclear Science and Technology Research Institute (NSTRI), Tehran 14155-1339, Iran
| | - Samaneh Zolghadri
- Nuclear Science and Technology Research Institute (NSTRI), Tehran 14155-1339, Iran.
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Zolghadri S, Yousefnia H, Jalilian AR, Fazaeli Y. Production, quality control, biodistribution assessment and preliminary dose evaluation of [177Lu]-tetra phenyl porphyrin complex as a possible therapeutic agent. BRAZ J PHARM SCI 2015. [DOI: 10.1590/s1984-82502015000200011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
<p>Due to interesting therapeutic properties of <sup>177</sup>Lu and tumor avidity of tetraphenyl porphyrins (TPPs), <sup>177</sup>Lu-tetraphenyl porphyrin was developed as a possible therapeutic compound. <sup>177</sup>Lu of 2.6-3 GBq/mg specific activity was obtained by irradiation of natural Lu<sub>2</sub>O<sub>3</sub>sample with thermal neutron flux of 4 × 10<sup>13</sup> n.cm<sup>-2</sup>.s<sup>-1</sup>. Tetraphenyl porphyrin was synthetized and labeled with <sup>177</sup>Lu. Radiochemical purity of the complex was studied using Instant thin layer chromatography (ITLC) method. Stability of the complex was checked in final formulation and human serum for 48 h. The biodistribution of the labeled compound in vital organs of wild-type rats was studied up to 7 d. The absorbed dose of each human organ was calculated by medical internal radiation dose (MIRD) method. A detailed comparative pharmacokinetic study was performed for <sup>177</sup>Lu cation and [<sup>177</sup>Lu]-TPP. The complex was prepared with a radiochemical purity: >97±1% and specific activity: 970-1000 MBq/mmol. Biodistribution data and dosimetric results showed that all tissues receive approximately an insignificant absorbed dose due to rapid excretion of the complex through the urinary tract. [<sup>177</sup>Lu]-TPP can be an interesting tumor targeting agent due to low liver uptake and very low absorbed dose of approximately 0.036 to the total body of human.</p>
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Shanehsazzadeh S, Yousefnia H, Jalilian AR, Zolghadri S, Lahooti A. Estimated human absorbed dose for 68Ga-ECC based on mice data: comparison with 67Ga-ECC. Ann Nucl Med 2015; 29:475-81. [DOI: 10.1007/s12149-015-0967-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/19/2015] [Indexed: 10/23/2022]
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Assessment of human effective absorbed dose of 67 Ga–ECC based on biodistribution rat data. Ann Nucl Med 2014; 29:118-24. [DOI: 10.1007/s12149-014-0917-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
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Zaman RT, Kosuge H, Pratx G, Carpenter C, Xing L, McConnell MV. Fiber-optic system for dual-modality imaging of glucose probes 18F-FDG and 6-NBDG in atherosclerotic plaques. PLoS One 2014; 9:e108108. [PMID: 25233472 PMCID: PMC4169475 DOI: 10.1371/journal.pone.0108108] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 08/19/2014] [Indexed: 12/02/2022] Open
Abstract
Background Atherosclerosis is a progressive inflammatory condition that underlies coronary artery disease (CAD)–the leading cause of death in the United States. Thus, the ultimate goal of this research is to advance our understanding of human CAD by improving the characterization of metabolically active vulnerable plaques within the coronary arteries using a novel catheter-based imaging system. The aims of this study include (1) developing a novel fiber-optic imaging system with a scintillator to detect both 18F and fluorescent glucose probes, and (2) validating the system on ex vivo murine plaques. Methods A novel design implements a flexible fiber-optic catheter consisting of both a radio-luminescence and a fluorescence imaging system to detect radionuclide 18F-fluorodeoxyglucose (18F-FDG) and the fluorescent analog 6-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-6-Deoxyglucose (6-NBDG), respectively. Murine macrophage-rich atherosclerotic carotid plaques were imaged ex vivo after intravenous delivery of 18F-FDG or 6-NBDG. Confirmatory optical imaging by IVIS-200 and autoradiography were also performed. Results Our fiber-optic imaging system successfully visualized both 18F-FDG and 6-NBDG probes in atherosclerotic plaques. For 18F-FDG, the ligated left carotid arteries (LCs) exhibited 4.9-fold higher radioluminescence signal intensity compared to the non-ligated right carotid arteries (RCs) (2.6×104±1.4×103 vs. 5.4×103±1.3×103 A.U., P = 0.008). Similarly, for 6-NBDG, the ligated LCs emitted 4.3-fold brighter fluorescent signals than the control RCs (1.6×102±2.7×101 vs. 3.8×101±5.9 A.U., P = 0.002). The higher uptake of both 18F-FDG and 6-NBDG in ligated LCs were confirmed with the IVIS-200 system. Autoradiography further verified the higher uptake of 18F-FDG by the LCs. Conclusions This novel fiber-optic imaging system was sensitive to both radionuclide and fluorescent glucose probes taken up by murine atherosclerotic plaques. In addition, 6-NBDG is a promising novel fluorescent probe for detecting macrophage-rich atherosclerotic plaques.
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Affiliation(s)
- Raiyan T. Zaman
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California, United States of America
- Division of Radiation Physics, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail:
| | - Hisanori Kosuge
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Guillem Pratx
- Division of Radiation Physics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Colin Carpenter
- Division of Radiation Physics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Lei Xing
- Division of Radiation Physics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Michael V. McConnell
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, California, United States of America
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Yousefnia H, Zolghadri S, Jalilian AR, Tajik M, Ghannadi-Maragheh M. Preliminary dosimetric evaluation of (166)Ho-TTHMP for human based on biodistribution data in rats. Appl Radiat Isot 2014; 94:260-265. [PMID: 25255303 DOI: 10.1016/j.apradiso.2014.08.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 08/11/2014] [Accepted: 08/31/2014] [Indexed: 10/24/2022]
Abstract
In this work, the absorbed dose to each organ of human for (166)Ho-TTHMP was evaluated based on biodistribution studies in rats by a RADAR method and was compared with (166)Ho-DOTMP as the only clinically used Ho-166 bone marrow ablative agent. The highest absorbed dose for this complex is observed in red marrow with 0.922mGy/MBq. The results show that (166)Ho-TTHMP has considerable characteristics compared to (166)Ho-DOTMP and can be a good candidate for bone marrow ablation in patients with multiple myeloma.
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Affiliation(s)
- Hassan Yousefnia
- Nuclear Science and Technology Research Institute (NSTRI), Tehran 14395-836, Iran
| | - Samaneh Zolghadri
- Nuclear Science and Technology Research Institute (NSTRI), Tehran 14395-836, Iran.
| | - Amir Reza Jalilian
- Nuclear Science and Technology Research Institute (NSTRI), Tehran 14395-836, Iran
| | - Mojtaba Tajik
- School of Physics, Damghan University, Damghan 36716-41167, Iran
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Production, quality control, biodistribution assessment and preliminary dose evaluation of 177Lu-PDTMP as a possible bone palliative agent. Nucl Med Commun 2014; 35:99-107. [DOI: 10.1097/mnm.0000000000000018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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CONA MARLEINMIRANDA, KOOLE MICHEL, FENG YUANBO, LIU YEWEI, VERBRUGGEN ALFONS, OYEN RAYMOND, NI YICHENG. Biodistribution and radiation dosimetry of radioiodinated hypericin as a cancer therapeutic. Int J Oncol 2013; 44:819-29. [DOI: 10.3892/ijo.2013.2217] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/01/2013] [Indexed: 12/26/2022] Open
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Dosimetric Analyses of Kidneys, Liver, Spleen, Pituitary Gland, and Neuroendocrine Tumors of Patients Treated With 177Lu-DOTATATE. Clin Nucl Med 2013; 38:188-94. [DOI: 10.1097/rlu.0b013e3182814ac1] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Islamian JP, Toossi MTB, Momennezhad M, Zakavi SR, Sadeghi R, Ljungberg M. Monte carlo study of the effect of collimator thickness on T-99m source response in single photon emission computed tomography. World J Nucl Med 2013; 11:70-4. [PMID: 23372440 PMCID: PMC3555397 DOI: 10.4103/1450-1147.103419] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In single photon emission computed tomography (SPECT), the collimator is a crucial element of the imaging chain and controls the noise resolution tradeoff of the collected data. The current study is an evaluation of the effects of different thicknesses of a low-energy high-resolution (LEHR) collimator on tomographic spatial resolution in SPECT. In the present study, the SIMIND Monte Carlo program was used to simulate a SPECT equipped with an LEHR collimator. A point source of 99mTc and an acrylic cylindrical Jaszczak phantom, with cold spheres and rods, and a human anthropomorphic torso phantom (4D-NCAT phantom) were used. Simulated planar images and reconstructed tomographic images were evaluated both qualitatively and quantitatively. According to the tabulated calculated detector parameters, contribution of Compton scattering, photoelectric reactions, and also peak to Compton (P/C) area in the obtained energy spectrums (from scanning of the sources with 11 collimator thicknesses, ranging from 2.400 to 2.410 cm), we concluded the thickness of 2.405 cm as the proper LEHR parallel hole collimator thickness. The image quality analyses by structural similarity index (SSIM) algorithm and also by visual inspection showed suitable quality images obtained with a collimator thickness of 2.405 cm. There was a suitable quality and also performance parameters’ analysis results for the projections and reconstructed images prepared with a 2.405 cm LEHR collimator thickness compared with the other collimator thicknesses.
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Affiliation(s)
- Jalil Pirayesh Islamian
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Chu KH, Lin YT, Hsu CC, Chen CY, Pan LK. Evaluation of effective dose for a patient under Ga-67 nuclear examination using TLD, water phantom and a simplified model. JOURNAL OF RADIATION RESEARCH 2012; 53:989-98. [PMID: 22915780 PMCID: PMC3483851 DOI: 10.1093/jrr/rrs050] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 06/08/2012] [Accepted: 06/12/2012] [Indexed: 06/01/2023]
Abstract
This study evaluated the effective dose of Ga-67 for a patient undergoing Ga-67 citrate nuclear examination by applying thermoluminescent dosimeter (TLD) technique and an indigenous water phantom. The Ga-67 radionuclide remaining in the body inevitably generated a measurable internal dose even though gamma camera scanning took only minutes to complete the clinical examination. For effective simulation of the cumulated effective dose for a patient undergoing examination, 150 TLDs were placed inside the water phantom for 6 days to monitor the gamma ray dose from the distributed Ga-67 citrate solution. The inserted TLDs represented internal organs, and the effective dose was calculated according to data in the ICRP-60 report. The water phantom was designed to model the body of a healthy human weighing 70 kg, and the water that was mixed with Ga-67 citrate solution was slowly replaced with fresh feed water to yield the required biological half life of the phantom. After continuously feeding in fresh water throughout the 6 days of TLD exposure, the TLDs were analyzed to determine the effective doses from the various biological half lives of the phantom. The derived effective dose of 185 MBq Ga-67 citrate solution for male/female (M/F) was 10.7/12.2, 10.7/12.0, 8.7/9.9 and 6.0/6.8 mSv, of biological half lives of 6.0, 4.5, 3.0 and 1.5 days, respectively. Although these experimental results correlated well with earlier empirical studies, they were lower than most calculated values. The cumulated uncertainty in the effective dose was 12.5-19.4%, which was acceptable in terms of both TLD counting statistic and reproducibility.
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Affiliation(s)
- Kuang Hua Chu
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 40609, Taiwan
- Cardiovascular Center, Taichung Veterans General Hospital, Taichung 40705, Taiwan
| | - Yu Ting Lin
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 40609, Taiwan
- Department of Radiology, China Medical University Beigang Hospital, Yunlin 65152, Taiwan
| | - Chia Chun Hsu
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 40609, Taiwan
- Department of Radiology, Buddhist Tzu Chi General Hospital, Taichung Branch, Taichung County 427, Taiwan
| | - Chien Yi Chen
- School of Medical Imaging and Radiological Science, Chung Shan Medical University, Taichung 402, Taiwan
| | - Lung Kwang Pan
- Graduate Institute of Radiological Science, Central Taiwan University of Science and Technology, Takun, Taichung 40609, Taiwan
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Shi CB, Yuan B, Lu JR, Xu JL, Yang WD, Deng JL, Wang J. Continuous low-dose-rate radiation of radionuclide phosphorus-32 for hemangiomas. Cancer Biother Radiopharm 2012; 27:198-203. [PMID: 22364418 DOI: 10.1089/cbr.2011.0995] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The study goal was to clarify the therapeutic effect and the absorbed dose of radionuclide phosphorus-32 for skin hemangiomas and the consequent risk of side effects in these patients. Phosphorus-32 is an β emitter and is used for skin hemangioma treatment. In comparison with the few Gy per minute of the linear accelerators, the dose rate of phosphorus-32 for hemangiomas is much <1 Gy/hour; so, the latter is called low-dose-rate radiation. To achieve the therapeutic dose, continuous hours or days of radiation is necessary. For strawberry hemangiomas, the phosphorus-32 applicator was tightly placed on the lesion site for several hours until reaching therapeutic dose. The absorbed dose was estimated by radiochromic films. The absorbed dose of phosphorus-32 irradiation declined exponentially with a depth from 0 to 2.5 mm. Of the 316 patients with strawberry hemangiomas, the lesion disappeared completely within 3 months after one-time treatment in 259 cases (82%). For cavernous hemangiomas, 370KBq phosphorus-32 colloid was injected into the hemangioma each square centimeter, and the absorbed radiation was estimated by theoretical calculation. Forty-two of the 58 patients with cavernous hemangiomas (72%) had lesions that completely disappeared within 3 months after receiving one to six treatments. Thus, the phosphorus-32 for strawberry hemangiomas and the chromium phosphate-32 colloid for cavernous hemangiomas were clearly efficacious.
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Affiliation(s)
- Chang-Bei Shi
- Department of Nuclear Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
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Freudenberg R, Wendisch M, Kotzerke J. Geant4-Simulations for cellular dosimetry in nuclear medicine. Z Med Phys 2011; 21:281-9. [DOI: 10.1016/j.zemedi.2011.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 08/29/2011] [Accepted: 08/29/2011] [Indexed: 10/16/2022]
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Changlai SP, Chang PJ, Chen CY. Biodistribution and dosimetry of (131)I in thyroidectomy patients using semiquantitative gamma-camera imaging. Cancer Biother Radiopharm 2010; 23:759-66. [PMID: 19111047 DOI: 10.1089/cbr.2008.0488] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to determine the biodistribution, effective retention half-time (T(eff)), and internal organ dosimetry of (131)I administered to patients with papillary thyroid cancer after a total or near total thyroidectomy, and whole-body and organ activity was measured by gamma-camera imaging at 16 time points over 5 days following the administration of 1.1 GBq of (131)I in 5 patients. Whole-body scanning was performed by using a Siemens E-CAM() gamma-camera at a fixed distance of 5 cm from the patient. (131)I activity in regions of interest (ROIs) corresponding to the bladder, heart wall, kidneys, liver, lower gastrointestinal tract, lung, stomach, and thyroid remnants were measured, with measurements in the thigh used as the background. Most activity was localized to the lower gastrointestinal tract and thyroid remnants on day 1. The longest T(eff) was in the lung and the shortest was in the bladder (34.0 and 16.8 hours, respectively). The three organs with the highest absorbed doses per unit of administered activity were the lower gastrointestinal tract (2.03 mSv/MBq), the stomach (1.32 mSv/MBq), and the heart wall (1.24 mSv/MBq). T(eff) for thyroid remnants and the whole body were also estimated. We evaluated these organ doses to determine the normal tissues most likely at risk for stochastic and deterministic effects associated with (131)I therapy for thyroid cancer and benign disease. Our results represent preliminary findings, and the study will continue to accrue a greater number of study participants.
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Affiliation(s)
- Sheng-Pin Changlai
- Medical Imaging Department, Buddhist Tzu Chi General Hospital, Taiwan, Republic of China
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Bouchat V, Nuttens VE, Michiels C, Masereel B, Feron O, Gallez B, Vander Borght T, Lucas S. Radioimmunotherapy with radioactive nanoparticles: biological doses and treatment efficiency for vascularized tumors with or without a central hypoxic area. Med Phys 2010; 37:1826-39. [PMID: 20443505 DOI: 10.1118/1.3368599] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Radioactive atoms attached to monoclonal antibodies are used in radioimmunotherapy to treat cancer while limiting radiation to healthy tissues. One limitation of this method is that only one radioactive atom is linked to each antibody and the deposited dose is often insufficient to eradicate solid and radioresistant tumors. In a previous study, simulations with the Monte Carlo N-Particle eXtended code showed that physical doses up to 50 Gy can be delivered inside tumors by replacing the single radionuclide by a radioactive nanoparticle of 5 nm diameter containing hundreds of radioactive atoms. However, tumoral and normal tissues are not equally sensitive to radiation, and previous works did not take account the biological effects such as cellular repair processes or the presence of less radiosensitive cells such as hypoxic cells. METHODS The idea is to adapt the linear-quadratic expression to the tumor model and to determine biological effective doses (BEDs) delivered through and around a tumor. This BED is then incorporated into a Poisson formula to determine the shell control probability (SCP) which predicts the cell cluster-killing efficiency at different distances "r" from the center of the tumor. BED and SCP models are used to analyze the advantages of injecting radioactive nanoparticles instead of a single radionuclide per vector in radioimmunotherapy. RESULTS Calculations of BED and SCP for different distances r from the center of a solid tumor, using the non-small-cell lung cancer as an example, were investigated for 90Y2O3 nanoparticles. With a total activity of about 3.5 and 20 MBq for tumor radii of 0.5 and 1.0 cm, respectively, results show that a very high BED is deposited in the well oxygenated part of the spherical carcinoma. CONCLUSIONS For either small or large solid tumors, BED and SCP calculations highlight the important benefit in replacing the single beta-emitter 90Y attached to each antibody by a 90Y2O3 nanoparticle.
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Affiliation(s)
- V Bouchat
- Research Center in Physics of Matter and Radiation, Laboratoire d'Analyses par Réactions Nucléaires, University of Namur, Rue de Bruxelles 61, B-5000 Namur, Belgium.
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Huang YY, Ma KH, Tseng TW, Chou TK, Ng H, Mirsalis JC, Fu YK, Chu TC, Huang WS, Shiue CY. Biodistribution, toxicity and radiation dosimetry studies of the serotonin transporter radioligand 4-[18F]-ADAM in rats and monkeys. Eur J Nucl Med Mol Imaging 2009; 37:545-55. [PMID: 19820930 DOI: 10.1007/s00259-009-1281-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 09/04/2009] [Indexed: 11/24/2022]
Abstract
PURPOSE 4-[(18)F]-ADAM is a potent serotonin transport imaging agent. We studied its toxicity in rats and radiation dosimetry in monkeys before human studies are undertaken. METHODS Single and multiple-dosage toxicity studies were conducted in Sprague-Dawley rats. Male and female rats were injected intravenously with 4-F-ADAM as a single dose of 1,023.7 microg/kg (1,000 times the human dose) or as five consecutive daily doses of 102.37 microg/kg (100 times the human dose). PET/CT scans were performed in seven Formosa Rock monkeys (four males and three females) using a Siemens Biograph scanner. After injection of 4-[(18)F]-ADAM (182+/-8 MBq), a low dose CT scan and a series of eight whole-body PET scans were performed. Whole-body images were acquired in 3-D mode. Time-activity data of source organs were used to calculate the residence times and estimate the absorbed radiation dose using OLINDA/EXM software. RESULTS In the rats neither the single dose nor the five daily doses of 4-F-ADAM produced overt adverse effects clinically. In the monkeys the radiation doses received by most organs ranged between 7.1 and 35.7 microGy/MBq, and the urinary bladder was considered to be the critical organ. The effective doses extrapolated to male and female adult humans were 17.4 and 21.8 microSv/MBq, respectively. CONCLUSION Toxicity studies in Sprague-Dawley rats and radiation dosimetry studies in Formosa Rock monkeys suggested that 4-[(18)F]-ADAM is safe for use in human PET imaging studies.
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Affiliation(s)
- Ya-Yao Huang
- PET Center, Department of Nuclear Medicine, Tri-Service General Hospital, 325 Sec. 2, Cheng-Kung Rd., Neihu 114, Taipei, Taiwan
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Harrison J. Doses and risks from tritiated water and environmental organically bound tritium. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2009; 29:335-349. [PMID: 19690361 DOI: 10.1088/0952-4746/29/3/s02] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This short review provides an explanation of the calculation and use of the ICRP protection quantities, equivalent and effective dose, including the simplifications introduced by using radiation and tissue weighting factors. It discusses the dose coefficients (Sv Bq(-1) intake) provided by ICRP for intakes of tritiated water (HTO) and organically bound tritium (OBT) and considers uncertainties in the human and animal data on which they are based, including information on the relative biological effectiveness (RBE) of tritium beta particles compared to gamma and x-rays. The review also addresses the specific issue of dose coefficients for ingestion of OBT in Cardiff Bay fish. A distinction is drawn between the adequacy of the ICRP calculation of effective dose to a reference person for the purposes of planning and regulatory control, and the calculation of best estimates of dose and risk to individuals. ICRP will continue to use a radiation weighting factor of 1 for all low LET radiations in the calculation of effective dose, but specific RBE data should be used in risk estimates. Uncertainties in dose coefficients are small for HTO but greater for OBT. The generic consideration of OBT provided by ICRP may not be appropriate for specific organic forms such as OBT in fish.
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Affiliation(s)
- John Harrison
- HPA, Radiation Protection Division, CRCE, Chilton, Didcot, Oxon, UK
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Lu XQ, Kiger WS. Application of a Novel Microdosimetry Analysis and its Radiobiological Implication for High-LET Radiation. Radiat Res 2009; 171:646-56. [DOI: 10.1667/rr1612.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Harrison J. Biokinetic and dosimetric modelling in the estimation of radiation risks from internal emitters. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2009; 29:A81-A105. [PMID: 19454809 DOI: 10.1088/0952-4746/29/2a/s06] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The International Commission on Radiological Protection (ICRP) has developed biokinetic and dosimetric models that enable the calculation of organ and tissue doses for a wide range of radionuclides. These are used to calculate equivalent and effective dose coefficients (dose in Sv Bq(-1) intake), considering occupational and environmental exposures. Dose coefficients have also been given for a range of radiopharmaceuticals used in diagnostic medicine. Using equivalent and effective dose, exposures from external sources and from different radionuclides can be summed for comparison with dose limits, constraints and reference levels that relate to risks from whole-body radiation exposure. Risk estimates are derived largely from follow-up studies of the survivors of the atomic bombings at Hiroshima and Nagasaki in 1945. New dose coefficients will be required following the publication in 2007 of new ICRP recommendations. ICRP biokinetic and dosimetric models are subject to continuing review and improvement, although it is arguable that the degree of sophistication of some of the most recent models is greater than required for the calculation of effective dose to a reference person for the purposes of regulatory control. However, the models are also used in the calculation of best estimates of doses and risks to individuals, in epidemiological studies and to determine probability of cancer causation. Models are then adjusted to best fit the characteristics of the individuals and population under consideration. For example, doses resulting from massive discharges of strontium-90 and other radionuclides to the Techa River from the Russian Mayak plutonium plant in the early years of its operation are being estimated using models adapted to take account of measurements on local residents and other population-specific data. Best estimates of doses to haemopoietic bone marrow, in utero and postnatally, are being used in epidemiological studies of radiation-induced leukaemia. Radon-222 is the one internal emitter for which control of exposure is based on direct information on cancer risks, with extensive information available on lung cancer induction by radon progeny in mines and consistent data on risks in homes. The dose per unit (222)Rn exposure can be calculated by comparing lung cancer risk estimates derived for (222)Rn exposure and for external exposure of the Japanese survivors. Remarkably similar values are obtained by this method and by calculations using the ICRP model of the respiratory tract, providing good support for model assumptions. Other informative comparisons with risks from external exposure can be made for Thorotrast-induced liver cancer and leukaemia, and radium-induced bone cancer. The bone-seeking alpha emitters, plutonium-239 and radium isotopes, are poorer leukaemogens than predicted by models. ICRP dose coefficients are published as single values without consideration of uncertainties. However, it is clear that full consideration of uncertainties is appropriate when considering best estimates of doses and risks to individuals or specific population groups. An understanding of the component uncertainties in the calculation of dose coefficients can be seen as an important goal and should help inform judgements on the control of exposures. The routine consideration of uncertainties in dose assessments, if achievable, would be of questionable value when doses are generally maintained at small fractions of limits.
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Affiliation(s)
- John Harrison
- Health Protection Agency, Radiation Protection Division, CRCE, Chilton, Didcot, Oxon, OX11 0RQ, UK.
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Ferro-Flores G, Arteaga de Murphy C. Pharmacokinetics and dosimetry of 188 Re-pharmaceuticals. Adv Drug Deliv Rev 2008; 60:1389-401. [PMID: 18547675 DOI: 10.1016/j.addr.2008.04.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Accepted: 04/16/2008] [Indexed: 01/08/2023]
Abstract
The main objective of this review is to apportion current and new insight into the biodistribution, radiopharmacokinetics, dosimetry and cell targeting of rhenium-188 labeled radiopharmaceuticals used as therapeutic drugs. The emphasis lies on the generator obtained rhenium-188, its physical, therapeutic, dosimetric and coordinated compounds. Its use in radioimmunotherapy for lymphoma and other hematological diseases with monoclonal antibodies is discussed. Radiolabeled peptides to target cell receptors are an important field in nuclear medicine and in some research facilities are already being used, especially, somatostatin, bombesin and other peptides. Small molecules labeled with 188 Re are promising as therapeutic drugs. A review about some of the non-specific targeting molecules with therapeutic or pain palliation effect such as phosphonates, lipiodol, microparticles and other interesting molecules is included. Research on the labeling of biomolecules with the versatile rhenium-188 has contributed to the development of therapeutics with favorable pharmacokinetic and dosimetric properties for cancer treatment.
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Affiliation(s)
- Guillermina Ferro-Flores
- Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, México
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Harrison J, Day P. Radiation doses and risks from internal emitters. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2008; 28:137-159. [PMID: 18495991 DOI: 10.1088/0952-4746/28/2/r01] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This review updates material prepared for the UK Government Committee Examining Radiation Risks from Internal Emitters (CERRIE) and also refers to the new recommendations of the International Commission on Radiological Protection (ICRP) and other recent developments. Two conclusions from CERRIE were that ICRP should clarify and elaborate its advice on the use of its dose quantities, equivalent and effective dose, and that more attention should be paid to uncertainties in dose and risk estimates and their implications. The new ICRP recommendations provide explanations of the calculation and intended purpose of the protection quantities, but further advice on their use would be helpful. The new recommendations refer to the importance of understanding uncertainties in estimates of dose and risk, although methods for doing this are not suggested. Dose coefficients (Sv per Bq intake) for the inhalation or ingestion of radionuclides are published as reference values without uncertainty. The primary purpose of equivalent and effective dose is to enable the summation of doses from different radionuclides and from external sources for comparison with dose limits, constraints and reference levels that relate to stochastic risks of whole-body radiation exposure. Doses are calculated using defined biokinetic and dosimetric models, including reference anatomical data for the organs and tissues of the human body. Radiation weighting factors are used to adjust for the different effectiveness of different radiation types, per unit absorbed dose (Gy), in causing stochastic effects at low doses and dose rates. Tissue weighting factors are used to take account of the contribution of individual organs and tissues to overall detriment from cancer and hereditary effects, providing a simple set of rounded values chosen on the basis of age- and sex-averaged values of relative detriment. While the definition of absorbed dose has the scientific rigour required of a basic physical quantity, the same is not true of the ICRP protection quantities equivalent and effective dose (i.e. those measured in sieverts). The ICRP quantities are intended for practical application in radiological protection and the choice of radiation and tissue weighting factors used in their calculation involves simplifying assumptions regarded as acceptable for this purpose. Best estimates of doses and risks to individuals and specific population groups may be calculated using ICRP biokinetic and dosimetric approaches, but would require the use of best available information on RBE and age-, sex- and population-specific risk factors. Consideration of uncertainties is important in applications such as the assessment of the probability of cancer causation for an individual and in estimating doses in epidemiological studies. While the ICRP system of protection does not take explicit account of uncertainties, an understanding of the various contributions to uncertainty can be seen to be of value when making judgments on the optimisation of protection.
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Affiliation(s)
- John Harrison
- Health Protection Agency, Radiation Protection Division, CRCE, Chilton, Didcot, Oxon OX11 0RQ, UK.
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Guo JH, Teng GJ, Zhu GY, He SC, Deng G, He J. Self-expandable stent loaded with 125I seeds: feasibility and safety in a rabbit model. Eur J Radiol 2006; 61:356-61. [PMID: 17085003 DOI: 10.1016/j.ejrad.2006.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 09/30/2006] [Accepted: 10/03/2006] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To evaluate technical feasibility and acute and subacute radiotolerance of a self-expandable stent loaded with (125)I seeds in the rabbit esophagus. METHODS A self-expandable stent designed for esophageal application was made of 0.16mm nitinol wire and loaded with (125)I seeds (CIAE-6711). Twenty-seven stents with three different radioactive dosages (n=9 in each dosage group) were implanted in the esophagus of healthy rabbits, while nine stents alone were used as controls. The stents were perorally deployed into the esophagus under fluoroscopic guidance. Radiological follow-up included plain chest film, CT scan, and barium esophagography which were undertaken in all rabbits of each group at 2, 4, and 8 weeks, respectively, which were correlated to histopathological findings. The stented esophageal segments along with their adjacent tissues were harvested for histopathological examinations. RESULTS The stent was successfully deployed into the targeted esophageal segment in all rabbits. Neither (125)I seeds dislodged from the stent during the deployment, nor they did during the follow-up period. The greatest (16.2Gy) absorbed dose was found in the tissue 10mm from (125)I seeds at 8 weeks. Slight epithelial hyperplasia on the stent surface and submucosal inflammatory process developed at 2 weeks, which reached the peak at 8 weeks after the procedure. Significant thickness of the esophageal muscular layer was found at 8 weeks only in the groups with (125)I seeds. On radiologic follow-up, moderate strictures on both ends of the stents developed at 4 weeks and became severe at 8 weeks after the procedure in all groups. CONCLUSION Deployment of a self-expandable stent loaded with (125)I seeds is technically feasible and safe within the first 8 weeks. Acute and subacute radiotolerance of the treated esophagus and its adjacent tissues by (125)I seeds is well preserved in a healthy rabbit model.
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Affiliation(s)
- Jin-He Guo
- Department of Radiology, Zhong-Da Hospital, Southeast University, 87# Dingjiaqiao Road, Nanjing 210009, China
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Holte O, Skretting A, Bach-Gansmo T, Hol PK, Johnsrud K, Tønnesen HH, Karlsen J. Localized internal radiotherapy with 90Y particles embedded in a new thermosetting alginate gel: A feasibility study in pigs. Nucl Med Commun 2006; 27:185-90. [PMID: 16404233 DOI: 10.1097/01.mnm.0000194398.97195.d9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Internal radiotherapy requires the localization of the radionuclide to the site of action. A new injectable alginate gel formulation intended to undergo immediate gelation in tissues and capable of encapsulating radioactive particles containing 90Y was investigated. METHODS The formulation was injected intramuscularly, into the bone marrow compartment of the femur and intravenously, respectively, in pigs. The distribution of radioactivity in various tissues was determined. RESULTS Following intramuscular injection, more than 90% of the radioactivity was found at the site of injection. Following injection into bone marrow, 30-40% of the radioactivity was retained at the site of injection, but a considerable amount of radioactivity was also detected in the lungs (35-45%) and the liver (5-18%). Following intravenous injection, 80-90% of the radioactivity was found in the lungs. CONCLUSION The present formulation appears suitable for localized radiotherapy in organs and tissues having low perfusion.
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Kim JH, Whang JH, Kim CS. Paired-organ and other selected absorbed fraction for the Korean Reference Adult Male model. RADIATION PROTECTION DOSIMETRY 2006; 118:395-401. [PMID: 16357027 DOI: 10.1093/rpd/nci359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The authors have developed a mathematical model for calculating internal radionuclide dosimetry for the Korean Reference Adult Male, and have also derived paired-organ and other selected inter-organ photon-specific absorbed fractions for this model. Each lung, kidney and adrenal gland was set as a separate source region even though each of them shares an identical physiological function with their complementary half. The thyroid gland was also set as a source region. Specific absorbed fractions (SAFs) were then derived by selecting 10 photon energies from 0.02 to 4.0 MeV inclusive. For this purpose the Monte Carlo methodology was used, and the derived SAF was compared with the resulting value of MIRD Pamphlet No. 5 and ORNL TM-8381, both of which were derived on the basis of the ICRP-23 reference man. The comparison showed that MIRD No. 5 and ORNL TM-8381 resulted in a higher absorbed fraction, but the phantom created on the basis of the Korean reference man led to a higher SAF. The weight of the organs of the phantom, and the size and location of the trunk seem to account for the differences. The energy-dependent differences in the SAFs are considered to be related to the distance between the source and target regions, the composition of the intervening tissues, and the photon energies and mean free paths. Also, as a result of deriving SAFs after setting each separate lung, kidney and adrenal gland as a source region, it was found that, although they are of the same physiological function, each individual organ serves as a source region on its own. Differences were noted in SAFs exerted on the source and target organs in accordance with the location of the organs, that is, whether they were located to the left or right of the source organs. The SAF derived in this study can be used for a more accurate internal radionuclide dosimetry for Koreans and other Orientals whose physiology, lifestyle and dietary habits are similar to those of Koreans.
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Affiliation(s)
- J H Kim
- Department of Nuclear Engineering College of Advanced Technology, Kyung Hee University, Korea
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Shi C, Xu XG. Development of a 30-week-pregnant female tomographic model from computed tomography (CT) images for Monte Carlo organ dose calculations. Med Phys 2005; 31:2491-7. [PMID: 15487729 DOI: 10.1118/1.1778836] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Assessment of radiation dose and risk to a pregnant woman and her fetus is an important task in radiation protection. Although tomographic models for male and female patients of different ages have been developed using medical images, such models for pregnant women had not been developed to date. This paper reports the construction of a partial-body model of a pregnant woman from a set of computed tomography (CT) images. The patient was 30 weeks into pregnancy, and the CT scan covered the portion of the body from above liver to below pubic symphysis in 70 slices. The thickness for each slice is 7 mm, and the image resolution is 512x512 pixels in a 48 cm x 48 cm field; thus, the voxel size is 6.15 mm3. The images were segmented to identify 34 major internal organs and tissues considered sensitive to radiation. Even though the masses are noticeably different from other models, the three-dimensional visualization verified the segmentation and its suitability for Monte Carlo calculations. The model has been implemented into a Monte Carlo code, EGS4-VLSI (very large segmented images), for the calculations of radiation dose to a pregnant woman. The specific absorbed fraction (SAF) results for internal photons were compared with those from a stylized model. Small and large differences were found, and the differences can be explained by mass differences and by the relative geometry differences between the source and the target organs. The research provides the radiation dosimetry community with the first voxelized tomographic model of a pregnant woman, opening the door to future dosimetry studies.
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MESH Headings
- Body Burden
- Female
- Humans
- Imaging, Three-Dimensional/methods
- Imaging, Three-Dimensional/standards
- Models, Biological
- Models, Statistical
- Monte Carlo Method
- Organ Specificity
- Pregnancy/physiology
- Pregnancy/radiation effects
- Pregnancy Trimester, First/physiology
- Radiographic Image Interpretation, Computer-Assisted/methods
- Radiographic Image Interpretation, Computer-Assisted/standards
- Radiometry/methods
- Radiometry/standards
- Radiotherapy Dosage
- Radiotherapy Planning, Computer-Assisted/methods
- Radiotherapy Planning, Computer-Assisted/standards
- Relative Biological Effectiveness
- Tomography, X-Ray Computed/methods
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Affiliation(s)
- Chengyu Shi
- Nuclear Engineering and Engineering Physics Program, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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Lee C, Lee J, Lee C. The effect of unrealistic thyroid vertical position on thyroid dose in the MIRD phantom. Med Phys 2005; 31:2038-41. [PMID: 15305456 DOI: 10.1118/1.1764702] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Anatomically, the thyroid gland is placed in the lower neck, extending from the level of the fifth cervical vertebra down to the first thoracic vertebra. However, the thyroid of the Medical Internal Radiation Dose (MIRD) phantom, which has been widely used for dosimetric calculation, is located right above the top of the torso and is completely included in the neck region. To investigate the effect of the unrealistic position of the thyroid in the MIRD phantom on dose calculation, thyroid absorbed doses at various vertical positions were calculated for the idealized external broad parallel photon beam from anterior-posterior, posterior-anterior, right lateral (RLAT), and left lateral (LLAT) direction using the Monte Carlo method. The thyroid absorbed dose decreased by as much as about 60% for 0.05 MeV photon in both RLAT and LLAT irradiations when the thyroid was relocated to realistic position (inserted into the torso). The effective dose also decreased by 10%, consequently. The thyroid dose of the widely accepted stylized model, the MIRD phantom, is overestimated in RLAT and LLAT irradiation geometries.
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Affiliation(s)
- Choonsik Lee
- Innovative Technology Center for Radiation Safety, Hanyang University 17 Haengdang, Sungdong, Seoul 133-791, Korea.
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Shi CY, Xu XG, Stabin MG. Specific absorbed fractions for internal photon emitters calculated for a tomographic model of a pregnant woman. HEALTH PHYSICS 2004; 87:507-511. [PMID: 15551788 DOI: 10.1097/01.hp.0000133364.55155.09] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Specific absorbed fractions are essential for calculation of radiation dose from internal emitters. Existing specific absorbed fractions for pregnant women were calculated using the stylized models; in this work, a partial-body tomographic model for a pregnant woman was constructed from a rare set of CT images. Based on this tomographic model, the Monte Carlo code, EGS4-VLSI, was used to derive specific absorbed fractions. Monoenergetic, isotropic photon emitters from 15 keV to 4 MeV were distributed in different source organs, and doses were calculated to many target regions in the body. Even though the results showed general agreement with previous studies for higher energies, significant differences were also found, especially for lower energies. The main reasons for the differences are due to the variation of mass, geometry, and organ distances, and they demonstrate the influence of more realistic body models on dose calculations.
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Affiliation(s)
- C Y Shi
- Nuclear Engineering and Engineering Physics Programs, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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Dence CS, Herrero P, Schwarz SW, Mach RH, Gropler RJ, Welch MJ. Imaging myocardium enzymatic pathways with carbon-11 radiotracers. Methods Enzymol 2004; 385:286-315. [PMID: 15130745 DOI: 10.1016/s0076-6879(04)85016-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Affiliation(s)
- Carmen S Dence
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Fill UA, Zankl M, Petoussi-Henss N, Siebert M, Regulla D. Adult female voxel models of different stature and photon conversion coefficients for radiation protection. HEALTH PHYSICS 2004; 86:253-272. [PMID: 14982227 DOI: 10.1097/00004032-200403000-00003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper describes the construction of three adult female voxel models, two whole-body and one from head to thighs, from computed tomographic data of 3 women of different stature. Voxel models (also called phantoms) are human models based on computed tomographic or magnetic resonance images obtained from high resolution continuous scans of a single individual. The gray-scale data or information content of the medical images are interpreted into tissues (i.e., organs), a process known as segmentation. The phantoms, consisting of millions of volume elements, called voxels, provide a three-dimensional representation of the human body and the spatial form of its constituent organs and structures. They were initially developed for radiation protection purposes to estimate the organ and effective doses and hence the risk to a person or population due to an irradiation. This paper also presents conversion coefficients for idealized geometries of external photon exposures of energies 10 keV-1 MeV for the three female models, calculated with a Monte Carlo code. Until now there were not any published data on conversion coefficients for explicit female voxel models. Such sets of conversion coefficients exist for voxel adult males or for MIRD-type male, female, and hermaphrodite models. Numerical differences of the calculated conversion coefficients for the voxel female models and MIRD-type models can amount up to 60% or more for external exposures and are due to the improved anatomical realism of the voxel models. The size of the model also has an effect on the conversion coefficients, particularly for deeper lying organs and energies below 200 keV. The three separate sets of conversion coefficients allow one to choose the most suitable model according to the size of the individual as well as to study the dosimetric variations due to the size of the model.
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Affiliation(s)
- U A Fill
- GSF-National Research Center for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg, Germany
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48
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Niven E, Nahmias C. Absorbed dose to very low birth weight infants from 18F-fluorodeoxyglucose. HEALTH PHYSICS 2003; 84:307-316. [PMID: 12645765 DOI: 10.1097/00004032-200303000-00003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The radiation absorbed dose to very low birth weight infants from 18F-fluorodeoxyglucose was investigated. Ten newborns undergoing clinical positron tomography lung imaging were included in this study. Two consecutive 45-min dynamic scans immediately following intravenous injection of fluorodeoxyglucose were acquired; the first was over the head, and the second was over the chest. Time-activity curves were generated for the brain, heart wall, lungs, and, when visible, the kidneys. The cumulated activity measurements obtained were for the entire organ masses; these masses were much smaller than the corresponding organ masses for the newborn mathematical model. Patient-specific dosimetry yielded average doses of 2.5 x 10(-1) mGy MBq(-1) for the brain, 6.8 x 10(-1) mGy MBq(-1) for the heart wall, 2.2 x 10(-1) mGy MBq(-1) for the kidneys, and 4.4 x 10(-1) mGy MBq(-1) for the lungs. The effective dose was estimated to be 2.1 x 10(-1) mSv MBq(-1), which is half that previously published for newborns but still an order of magnitude higher than that for adults.
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MESH Headings
- Absorption
- Body Weight
- Brain/diagnostic imaging
- Brain/metabolism
- Computer Simulation
- Dose-Response Relationship, Radiation
- Female
- Fluorodeoxyglucose F18/administration & dosage
- Fluorodeoxyglucose F18/pharmacokinetics
- Half-Life
- Heart/diagnostic imaging
- Humans
- Infant, Newborn
- Infant, Premature, Diseases/diagnostic imaging
- Infant, Premature, Diseases/metabolism
- Infant, Very Low Birth Weight
- Injections, Intravenous
- Kidney/diagnostic imaging
- Kidney/metabolism
- Lung/diagnostic imaging
- Lung/metabolism
- Male
- Models, Biological
- Myocardium/metabolism
- Organ Specificity
- Pneumonia/diagnostic imaging
- Pneumonia/metabolism
- Radiation Dosage
- Radiometry/methods
- Radiopharmaceuticals/administration & dosage
- Radiopharmaceuticals/pharmacokinetics
- Sensitivity and Specificity
- Tissue Distribution
- Tomography, Emission-Computed
- Urinary Bladder/diagnostic imaging
- Urinary Bladder/metabolism
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Affiliation(s)
- E Niven
- Department of Nuclear Medicine. McMaster University Medical Centre, 1200 Main Street West, Hamilton, Ontario, Canada L8N 3Z5.
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Ljungberg M, Frey E, Sjögreen K, Liu X, Dewaraja Y, Strand SE. 3D absorbed dose calculations based on SPECT: evaluation for 111-In/90-Y therapy using Monte Carlo simulations. Cancer Biother Radiopharm 2003; 18:99-107. [PMID: 12667313 DOI: 10.1089/108497803321269377] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A general method is presented for patient-specific three-dimensional (3D) absorbed dose calculations based on quantitative SPECT activity measurements. The computational scheme includes a method for registration of the CT study to the SPECT image, and compensation for attenuation, scatter, and collimator-detector response including septal penetration, performed as part of an iterative reconstruction method. From SPECT images, the absorbed dose rate is calculated using an EGS4 Monte Carlo code, which converts the activity distribution to an absorbed dose rate distribution. Evaluation of the accuracy in the activity quantification and the absorbed dose calculation is based on realistic Monte Carlo simulated SPECT data of a voxel-computer phantom and (111)In and (90)Y. Septal penetration was not included in this study. The SPECT-based activity concentrations and absorbed dose distributions are compared to the actual values; the results imply that the corrections for attenuation and scatter yield results of high accuracy. The presented method includes compensation for most parameters deteriorating the quantitative image information. Inaccuracies are, however, introduced by the limited spatial resolution of the SPECT system, which are not fully compensated by the collimator-response correction. The proposed evaluation methodology may be used as a basis for future inter-comparison of different dosimetry calculation schemes.
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Sajjad M, Zaini MR, Liow JS, Rottenberg DA, Strother SC. Production and dosimetry of [14O]water for PET activation studies. Appl Radiat Isot 2002; 57:607-15. [PMID: 12433034 DOI: 10.1016/s0969-8043(02)00175-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
[14O]water was produced by the 14N(p,n)14O reaction in quantities greater than 80mCi (EOB). The carbon-11 impurity in the final product was approximately 0.003 +/- 0.002% of 14O activity at EOB. A factor of 0.5 +/- 0.02 was obtained to correct the dose calibrator for the additional 2.313 MeV gamma-ray. The effective dose equivalent was calculated for 14O and 15O using MIRDOSE, and the 14O dose was found to be approximately 70% of that for 15O. For scanner performance based on noise equivalent count measurements, the peak activity concentration for 14O was 30% lower than that for 15O. At their peak activity concentrations the noise equivalent count rate for 14O was found to be about 13% less than that for 15O.
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Affiliation(s)
- Munawwar Sajjad
- PET Imaging Service, Veterans Affairs Medical Center, Minneapolis, MN 55417, USA.
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