Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations

Purpose In voxel-based dosimetry, dose-voxel kernels (DVKs) represent the absorbed dose in a target voxel per decay in a source voxel. In this work, we aimed to validate DVKs generated using Particle and Heavy Ion Transport Code System (PHITS) as a first step in establishing a quantitative SPECT/CT...

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Main Authors: Tatu, Shalaine Sana, Kelley, Brian M., Wong, Yin How, Kasbollah, Azahari, Suppiah, Subapriya, Zhi Xin, Phuna, Kappadath, S. Cheenu, Yeong, Chai Hong
Format: Article
Language:English
Published: Springer Nature 2025
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Online Access:http://psasir.upm.edu.my/id/eprint/115842/
http://psasir.upm.edu.my/id/eprint/115842/1/Validation%20of%20Particle%20and%20Heavy%20Ion%20Transport%20Code%20System%20-PHITS.pdf
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author Tatu, Shalaine Sana
Kelley, Brian M.
Wong, Yin How
Kasbollah, Azahari
Suppiah, Subapriya
Zhi Xin, Phuna
Kappadath, S. Cheenu
Yeong, Chai Hong
author_facet Tatu, Shalaine Sana
Kelley, Brian M.
Wong, Yin How
Kasbollah, Azahari
Suppiah, Subapriya
Zhi Xin, Phuna
Kappadath, S. Cheenu
Yeong, Chai Hong
author_sort Tatu, Shalaine Sana
building UPM Institutional Repository
collection Online Access
description Purpose In voxel-based dosimetry, dose-voxel kernels (DVKs) represent the absorbed dose in a target voxel per decay in a source voxel. In this work, we aimed to validate DVKs generated using Particle and Heavy Ion Transport Code System (PHITS) as a first step in establishing a quantitative SPECT/CT-based dosimetry framework for selective internal radiation therapy (SIRT). Methods A 1-MBq source of 90Y, 153Sm, 177Lu, 188Re, and 166Ho located in central cubic voxels of 1 mm, 3 mm, and 6 mm dimension within soft tissue (1.04 g⋅cm−³), was simulated using 2.5 × 10⁷ histories in PHITS. The DVK results were compared to published data (Lanconelli et al., 2012). In a pilot study, 17 MBq of 153Sm microspheres were injected into a liver tumor-bearing rat and imaged 24 h later using SPECT/CT. SPECT/CT images were then converted to cumulated activity and convolved with a 153Sm DVK using Fast Fourier Transform in MATLAB to create an absorbed dose map. Results As expected, DVKs for the radionuclides showed a steep decrease from the source voxel to the maximum continuous slowing down approximation (CSDA) of beta components. Beyond the CSDA, gamma and bremsstrahlung contributed minimally (10⁻⁶ to 10⁻⁴) to voxel doses. Observed DVK changes as voxel size increased were in good agreement with published data, with differences in source voxel ranging from 1 to 24%. Rat imaging revealed 153Sm microspheres localized at injection sites, with mean and maximum doses of 45 Gy and 194 Gy, respectively. Conclusion The DVKs calculated in PHITS were successfully validated. 153Sm dose maps were produced from SPECT/CT images in a rat model. Further studies on the application of DVKs in heterogeneous media will be conducted.
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spelling upm-1158422025-03-13T05:06:09Z http://psasir.upm.edu.my/id/eprint/115842/ Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations Tatu, Shalaine Sana Kelley, Brian M. Wong, Yin How Kasbollah, Azahari Suppiah, Subapriya Zhi Xin, Phuna Kappadath, S. Cheenu Yeong, Chai Hong Purpose In voxel-based dosimetry, dose-voxel kernels (DVKs) represent the absorbed dose in a target voxel per decay in a source voxel. In this work, we aimed to validate DVKs generated using Particle and Heavy Ion Transport Code System (PHITS) as a first step in establishing a quantitative SPECT/CT-based dosimetry framework for selective internal radiation therapy (SIRT). Methods A 1-MBq source of 90Y, 153Sm, 177Lu, 188Re, and 166Ho located in central cubic voxels of 1 mm, 3 mm, and 6 mm dimension within soft tissue (1.04 g⋅cm−³), was simulated using 2.5 × 10⁷ histories in PHITS. The DVK results were compared to published data (Lanconelli et al., 2012). In a pilot study, 17 MBq of 153Sm microspheres were injected into a liver tumor-bearing rat and imaged 24 h later using SPECT/CT. SPECT/CT images were then converted to cumulated activity and convolved with a 153Sm DVK using Fast Fourier Transform in MATLAB to create an absorbed dose map. Results As expected, DVKs for the radionuclides showed a steep decrease from the source voxel to the maximum continuous slowing down approximation (CSDA) of beta components. Beyond the CSDA, gamma and bremsstrahlung contributed minimally (10⁻⁶ to 10⁻⁴) to voxel doses. Observed DVK changes as voxel size increased were in good agreement with published data, with differences in source voxel ranging from 1 to 24%. Rat imaging revealed 153Sm microspheres localized at injection sites, with mean and maximum doses of 45 Gy and 194 Gy, respectively. Conclusion The DVKs calculated in PHITS were successfully validated. 153Sm dose maps were produced from SPECT/CT images in a rat model. Further studies on the application of DVKs in heterogeneous media will be conducted. Springer Nature 2025-01-14 Article PeerReviewed text en http://psasir.upm.edu.my/id/eprint/115842/1/Validation%20of%20Particle%20and%20Heavy%20Ion%20Transport%20Code%20System%20-PHITS.pdf Tatu, Shalaine Sana and Kelley, Brian M. and Wong, Yin How and Kasbollah, Azahari and Suppiah, Subapriya and Zhi Xin, Phuna and Kappadath, S. Cheenu and Yeong, Chai Hong (2025) Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations. Health and Technology. pp. 1-6. ISSN 2190-7196 https://link.springer.com/journal/12553 Imaging systems in medicine Dosimetry 10.1007/s12553-025-00940-4
spellingShingle Imaging systems in medicine
Dosimetry
Tatu, Shalaine Sana
Kelley, Brian M.
Wong, Yin How
Kasbollah, Azahari
Suppiah, Subapriya
Zhi Xin, Phuna
Kappadath, S. Cheenu
Yeong, Chai Hong
Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title_full Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title_fullStr Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title_full_unstemmed Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title_short Validation of particle and heavy ion transport code system (PHITS) in generating dose-voxel kernels for internal dosimetry calculations
title_sort validation of particle and heavy ion transport code system (phits) in generating dose-voxel kernels for internal dosimetry calculations
topic Imaging systems in medicine
Dosimetry
url http://psasir.upm.edu.my/id/eprint/115842/
http://psasir.upm.edu.my/id/eprint/115842/
http://psasir.upm.edu.my/id/eprint/115842/
http://psasir.upm.edu.my/id/eprint/115842/1/Validation%20of%20Particle%20and%20Heavy%20Ion%20Transport%20Code%20System%20-PHITS.pdf