Varian23EX加速器多叶准直器的蒙特卡罗模拟及测量验证

摘要

目的：基于蒙特卡罗方法建立Varian直线加速器多叶准直器模型，用于模拟任意形状的射束分布。方法根据厂家技术文档中多叶准直器的机械参数，使用BEAMnrc的组件DYNVMLC模拟多叶准直器的几何结构，通过对比蒙特卡罗模拟结果和测量结果来验证该模型。结果蒙特卡罗计算结果和测量结果基本一致，偏差在3%以内。结论使用蒙特卡罗方法精确建立了Varian直线加速器多叶准直器模型，可以用于分析多叶准直器几何属性对剂量分布的影响。%Objective To simulate the multi-leaf collimator of Varian linear accelerator using Monte Carlo method. Methods The multi-leaf collimator model was established using the DYNVMLC module of BEAMnrc and validated by comparison of Monte Carlo simulation and actual measurement results. Results The simulation results were well consistent with the actual measurement results with a bias of less than 3%. Conclusion The multi-leaf collimator of Varian linear accelerator can be successfully modeled using Monte Carlo method for analysis of the impact of the geometric properties of the multi-leaf collimator on the dose distribution.