基于蒙特卡罗方法确定医用加速器最优电子线参数

张帆; 肖爱农; 伍海彪; 艾小红; 屈国普; 李翩; 李文军; 蔡曼波

doi:10.11889/j.0253-3219.2018.hjs.41.060201

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基于蒙特卡罗方法确定医用加速器最优电子线参数

低能加速器技术、射线技术及应用 | 更新时间：2021-05-19

- 基于蒙特卡罗方法确定医用加速器最优电子线参数
- Optimalizing electron beam parameters of linear accelerator based on Monte Carlo simulation
- 核技术 2018年41卷第6期文章编号：060201
- 作者机构：
  
  1.南华大学附属第一医院放疗科衡阳 421001
  2.南华大学核科学技术学院衡阳 421001
- 作者简介：
  
  [ "张帆, 男, 1991年出生, 2014年毕业于湖南师范大学, 现为硕士研究生, 研究领域为医学物理", "ZHANG Fan, male, born in 1991, graduated from Hunan Normal University in 2014, master student, focusing on medical physics" ]
  [ "肖爱农, 男, 1965年出生, 1998年毕业于衡阳医学院, 副主任医师, 研究领域为肿瘤放射治疗", "XIAO Ainong, male, born in 1965, graduated from Hengyang Medical College in 1998, focusing on radiation oncology" ]
  伍海彪, E-mail:wuhaibiao@163.com WU Haibiao, E-mail: wuhaibiao@163.com
- 基金信息：
  
  湖南省重点研发计划(2015SK2022);湖南省自然科学青年基金项目(2016JJ3108)
- DOI：10.11889/j.0253-3219.2018.hjs.41.060201
  中图分类号： TL53
- 收稿日期：2018-02-05，
  
  修回日期：2018-03-13，
  
  纸质出版日期：2018-06-10
- 稿件说明：
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张帆, 肖爱农, 伍海彪, 等. 基于蒙特卡罗方法确定医用加速器最优电子线参数[J]. 核技术, 2018,41(6):060201

Fan ZHANG, Ainong XIAO, Haibiao WU, et al. Optimalizing electron beam parameters of linear accelerator based on Monte Carlo simulation[J]. Nuclear techniques, 2018, 41(6): 060201
张帆, 肖爱农, 伍海彪, 等. 基于蒙特卡罗方法确定医用加速器最优电子线参数[J]. 核技术, 2018,41(6):060201 DOI： 10.11889/j.0253-3219.2018.hjs.41.060201.

Fan ZHANG, Ainong XIAO, Haibiao WU, et al. Optimalizing electron beam parameters of linear accelerator based on Monte Carlo simulation[J]. Nuclear techniques, 2018, 41(6): 060201 DOI： 10.11889/j.0253-3219.2018.hjs.41.060201.

摘要

通过蒙特卡罗方法模拟瓦里安IX加速器6 MV能量档、10 cm×10 cm射野下的剂量分布，研究电子线参数对剂量分布的影响，并寻找确定最优电子线参数的简化方法。结果表明：当电子线平均能量和径向强度分布分别在5.5~6.4 MeV及0.1~0.4 cm变化时，百分深度剂量没有显著变化；当径向强度分布在0~0.19 cm变化时，主剂量区内模拟与测量的离轴剂量差异很小，但在半影区，二者之间有较大差异；通过调整平均角展宽，可以使不同深度处模拟与测量的离轴剂量有更好的符合度。根据本文提出的电子线参数确定方法可以使模拟的剂量更为精确，由于百分深度剂量与离轴剂量分别对径向强度分布及平均能量不敏感，各参数可以独立地根据单一剂量分布确定。

Abstract

Background

With the development of radiation technology

it needs to improve the accuracy of dose simulation.

Purpose

Build up a simplified benchmarking procedure to determine the incident electron beam parameters independently using a Monte Carlo linear accelerator model.

Methods

A 10 cm×10 cm field is simulated to acquire the parameters influence on the dose distributions for Varian Ⅸ 6 MV megavoltage electron beams.

Results

The calculated depth doses had no significant changes when the electron mean energy and radial intensity varied in 5.5~6.4 MeV and 0.1~0.4 cm respectively. And the dose profile simulated with an electron radial intensity in 0~0.19 cm had a good agreement with the measured dose profile in the main field while obvious discrepancies in the penumbra region. The mean angular spread was found to be 0.3° to get good matching between calculations and measurements at all considered depths.

Conclusion

Accurate dose distributions are achieved by using the incident electron beam parameters benchmarked with the proposed procedure. As the percentage depth doses and dose profiles are insensitive to the electron energy and radial intensity correspondingly

they are feasible to benchmark individually.

关键词

Keywords

references

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