Earticle

초록

영어

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 DCs. Results 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 cases. Conclusion: 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.

목차

ABSTRACT
Introduction
Materials and Methods
1. Computed Tomography Images
2. Organ Segmentations
3. Monte Carlo Simulations
Results and Discussion
1. Segmented Organs of 30 Patients
2. Individual Variation in Organ Doses
3. Discussion
Conclusion
Conflict of Interest
Acknowledgements
Ethical Statement
Author Contribution
References

키워드

저자

• Yumi Lee [ Department of Radiation Convergence Engineering, Yonsei University, Wonju, Korea ]
• Ji Won Choi [ Department of Radiation Convergence Engineering, Yonsei University, Wonju, Korea ]
• Lior Braunstein [ Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, USA ]
• Choonsik Lee [ Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA ]
• Yeon Soo Yeom [ Department of Radiation Convergence Engineering, Yonsei University, Wonju, Korea ] Corresponding Author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  방사선방어학회지 [Journal of Radiation Protection and Research]

• 간기

  계간

• pISSN

  2508-1888

• 수록기간

  1976~2026

• 등재여부

  KCI 등재,SCOPUS

• 십진분류

  KDC 559 DDC 629