Earticle

초록

영어

Background: Monte Carlo (MC) simulation is the most accurate for calculating radiation dose distribution and determining patient dose. In MC simulations of the therapeutic accelerator, the characteristics of the initial electron must be precisely determined in order to achieve accurate simulations. However, It has been computation-, labor-, and time-intensive to predict the beam characteristics through predominantly empirical approach. The aim of this study was to analyze the relationships between electron beam parameters and dose distribution, with the goal of simplifying the MC commissioning process. Materials and Methods: The Varian Clinac 2300 IX machine was modeled with the Geant4 MC-toolkit. The percent depth dose (PDD) and lateral beam profiles were assessed according to initial electron beam parameters of mean energy, radial intensity distribution, and energy distribution. Results and Discussion: The PDD values increased on average by 4.36% when the mean energy increased from 5.6 MeV to 6.4 MeV. The PDD was also increased by 2.77% when the energy spread increased from 0 MeV to 1.019 MeV. In the lateral dose profile, increasing the beam radial width from 0 mm to 4 mm at the full width at half maximum resulted in a dose decrease of 8.42% on the average. The profile also decreased by 4.81% when the mean energy was increased from 5.6 MeV to 6.4 MeV. Of all tested parameters, electron mean energy had the greatest influence on dose distribution. The PDD and profile were calculated using parameters optimized and compared with the golden beam data. The maximum dose difference was assessed as less than 2%. Conclusion: The relationship between the initial electron and treatment beam quality investigated in this study can be used in Monte Carlo commissioning of medical linear accelerator model.

목차

ABSTRACT
 Introduction
 Materials and Methods
  1. LINAC head modeling based on the Geant4 toolkit
  2. Evaluation of the dosimetric effect according to initial electron beam parameters
  3. Simulation conditions for dose calculation
 Results
  1. Effects of the initial electron beam on the PDD and profile
  2. MC commissioning of the photon beam
 Discussion
 Conclusion
 Acknowledgments
 References

키워드

저자

• Hyojun Park [ Department of Radiation Convergence Engineering, Yonsei University, Wonju, Korea ]
• Hyun Joon Choi [ Department of Radiation Convergence Engineering, Yonsei University, Wonju, Korea ]
• Jung-In Kim [ Department of Radiation Oncology, Seoul National University Hospital, Seoul, Korea ]
• Chul Hee Min [ 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