Monte Carlo-based simulation of influence of linear accelerator beam parameter on percentage depth dose
10.3760/cma.j.issn.0254-5098.2018.02.013
- VernacularTitle:医用加速器射线参数对百分深度剂量影响的蒙特卡罗模拟
- Author:
Fan ZHANG
1
;
Haibiao WU
;
Ainong XIAO
;
Xiaohong AI
;
Manbo CAI
;
Pian LI
;
Lixiang CHENG
;
Zhenchao ZHANG
;
Guopu QU
Author Information
1. 南华大学核科学技术学院
- Keywords:
Monte Carlo;
Electron energy;
Radial intensity distribution;
Percentage depth dose
- From:
Chinese Journal of Radiological Medicine and Protection
2018;38(2):145-149
- CountryChina
- Language:Chinese
-
Abstract:
Objective To determine the optimal electron beam energy at different field size through a Monte Carlo-based simulation of the therapy head of Varian X 6 MV linear accelerator so as to study the influence of radial intensity on depth dose.Methods Firstly,keeping the radial intensity unchanged for the field of interest while changing electron beam energy,compassion was carried out of calculated percentage depth doses between measured values.Thus,the optimal energy was identified for this field size.Then,the obtained energy was set the optimal value to study the radial intensity influence on the depth doses.Results The optimal electron energy for 4 cm ×4 cm,10 cm × 10 cm,20 cm × 20 cm and 30 cm × 30 cm field sizes was 5.9,6.0,6.3 and 6.4 MeV respectively.Changes in radial intensities resulted in negligible changes in percentage depth doses for4 cm ×4-cm and 10 cm × 10 cm fields,but led to observable discrepancy for 20 cm × 20 cm and 30 cm × 30 cm fields.Conclusions The optimal electron energies for different field sizes are slightly different.Change in radial intensity distribution has significant influence on the depth dose for large field.To improve simulation accuracy,the field size needs to be taken into consideration in determining the electron beam energy and radial intensity distribution.
