Dose coefficients of percentile-specific computational phantoms for photon external exposures

Yeom, Yeon Soo; Han, Haegin; Choi, Chang Gyu; Shin, Bangho; Kim, Chan Hyeong; Lee, Choonsik

doi:10.1007/s00411-019-00818-w

Cited by 7 publications

(2 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In other words, the individual dose variation becomes smaller at higher energies, practically resulting in the variation for most cases being considered negligibly small at the photon energies from 0.2 MeV to 10 MeV. Such similar trend was also observed in a previous study [20] that investigated the body size dependency on organ dose calculations for photon external exposures using a set of percentile-specific phantoms constructed from the ICRP mesh-type reference phantoms (ICRP 2020) [21]. At this energy region (0.2-10 MeV), of course, the ICRP-116 organ DCs derived from the ICRP reference voxel phantoms (ICRP 2009) [3] also showed an excellent agreement with those of the patients calculated in this study.…”

Section: Discussionsupporting

confidence: 88%

Investigation on Individual Variation of Organ Doses for Photon External Exposures: A Monte Carlo Simulation Study

Lee,

Choi,

Braunstein

et al. 2024

J Radiat Prot Res

Self Cite

View full text Add to dashboard Cite

Background: The reference dose coefficients (DCs) of the International Commission on Radiological Protection (ICRP) have been widely used to estimate organ doses of individuals for risk assessments. This approach has been well accepted because individual anatomy data are usually unavailable, although dosimetric uncertainty exists due to the anatomical difference between the reference phantoms and the individuals. We attempted to quantify the individual variation of organ doses for photon external exposures by calculating and comparing organ DCs for 30 individuals against the ICRP reference DCs.Materials and Methods: We acquired computed tomography images from 30 patients in which eight organs (brain, breasts, liver, lungs, skeleton, skin, stomach, and urinary bladder) were segmented using the ImageJ software to create voxel phantoms. The phantoms were implemented into the Monte Carlo N-Particle 6 (MCNP6) code and then irradiated by broad parallel photon beams (10 keV to 10 MeV) at four directions (antero-posterior, postero-anterior, left-lateral, right-lateral) to calculate organ DCsResults and Discussion: There was significant variation in organ doses due to the difference in anatomy among the individuals, especially in the kilovoltage region (e.g., <100 keV). For example, the red bone marrow doses at 0.01 MeV varied from 3 to 7 orders of the magnitude depending on the irradiation geometry. In contrast, in the megavoltage region (1–10 MeV), the individual variation of the organ doses was found to be negligibly small (differences <10%). It was also interesting to observe that the organ doses of the ICRP reference phantoms showed good agreement with the mean values of the organ doses among the patients in many casesConclusion: The results of this study would be informative to improve insights in individualspecific dosimetry. It should be extended to further studies in terms of many different aspects (e.g., other particles such as neutrons, other exposures such as internal exposures, and a larger number of individuals/patients) in the future.

show abstract

Section: Discussionsupporting

confidence: 88%

Investigation on Individual Variation of Organ Doses for Photon External Exposures: A Monte Carlo Simulation Study

Lee,

Choi,

Braunstein

et al. 2024

J Radiat Prot Res

Self Cite

View full text Add to dashboard Cite

show abstract

“…Such in vitro studies could be conducted more efficiently, but may require a modified exposure profile, perhaps guided by computational studies, to reflect the actual exposure the specific organ would receive after the neutron component has interacted with other tissues surrounding the organ. Computational human phantoms, created by the National Cancer Institute (NCI; Bethesda, MD), can be used to estimate external exposures, organ depth distributions and dose estimation (85)(86)(87). Perhaps this technology can be adapted to help with neutron dosimetry, and researchers can learn from the valuable contributions of the radiotherapy community.…”

Section: Animal Model Parametersmentioning

confidence: 99%

Neutron Radiobiology and Dosimetry

et al. 2021

View full text Add to dashboard Cite

As the U.S. prepares for the possibility of a radiological or nuclear incident, or anticipated lunar and Mars missions, the exposure of individuals to neutron radiation must be considered. More information is needed on how to determine the neutron dose to better estimate the true biological effects of neutrons and mixed-field (i.e., neutron and photon) radiation exposures. While exposure to gamma-ray radiation will cause significant health issues, the addition of neutrons will likely exacerbate the biological effects already anticipated after radiation exposure. To begin to understand the issues and knowledge gaps in these areas, the National Institute of Allergy and Infectious Diseases (NIAID), Radiation Nuclear Countermeasures Program (RNCP), Department of Defense (DoD), Defense Threat Reduction Agency (DTRA), and National Aeronautics and Space Administration (NASA) formed an inter-agency working group to host a Neutron Radiobiology and Dosimetry Workshop on March 7, 2019 in Rockville, MD. Stakeholder interests were clearly positioned, given the differences in the missions of each agency. An overview of neutron dosimetry and neutron radiobiology was included, as well as a historical overview of neutron exposure research. In addition, current research in the fields of biodosimetry and diagnostics, medical countermeasures (MCMs) and treatment, long-term health effects, and computational studies were presented and discussed.

show abstract

Voxel model of a rabbit: assessment of absorbed doses in organs after CT examination performed by two different protocols

Mitrovic

Ciraj-Bjelac

Jovanović

et al. 2021

Radiat Environ Biophys

View full text Add to dashboard Cite

Dose coefficients of percentile-specific computational phantoms for photon external exposures

Cited by 7 publications

References 20 publications

Investigation on Individual Variation of Organ Doses for Photon External Exposures: A Monte Carlo Simulation Study

Investigation on Individual Variation of Organ Doses for Photon External Exposures: A Monte Carlo Simulation Study

Neutron Radiobiology and Dosimetry

Voxel model of a rabbit: assessment of absorbed doses in organs after CT examination performed by two different protocols

Contact Info

Product

Resources

About