Monte Carlo dose calculation based on the virtual source model with linear accelerator and its preliminary application in independent dose calculation for IMRT plans
10.3760/cma.j.issn.1004-4221.2016.04.014
- VernacularTitle:基于直线加速器虚拟源模型的蒙特卡洛剂量计算及在IMRT独立验算中的初步应用
- Author:
Bin TANG
;
Shengwei KANG
;
Xianliang WANG
;
Jie LI
;
Pei WANG
- Publication Type:Journal Article
- Keywords:
Virtual head model;
Monte Carlo;
Dosimetry
- From:
Chinese Journal of Radiation Oncology
2016;25(4):372-375
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the feasibility of the virtual source model in Monte Carlo dose calculation for clinical radiotherapy.Methods The Monte Carlo simulation was used to obtain the phase space files which recorded the physical properties of the particles emitted by a medical linear accelerator, and the information on the type, energy spectrum, and distribution of particles were extracted from these files and analyzed to establish the semi-empirical model of virtual two-photon source.The GMC dose calculation engine was used to obtain the 3 cm×3 cm, 5 cm×5 cm, 10 cm×10 cm, 20 cm×20 cm, and 30 cm×30 cm fields of radiotherapy and the results of Monte Carlo simulation of dose distribution in three-dimensional water phantom in 2 intensity-modulated radiotherapy ( IMRT) plans.These results were compared with the results of water phantom measurement or the results of Elekta Monaco planning system to verify the accuracy of Monte Carlo dose calculation based on a virtual source.Results As for the percentage depth-dose distribution curves of the central axis of the water phantom and the off-axis dose curves at different depths in the five fields for radiotherapy, the difference between the results of Monte Carlo simulation and the results of measurement was within 1%.As for the two IMRT plans, the three-dimensional passing rates of Monaco calculation results and Monte Carlo simulation results were 98.9%and 99.4%, respectively, for 3%/3 mm, and 95.1%and 95.4%, respectively, for 2%/2 mm.Conclusions Monte Carlo simulation based on the virtual source model can obtain accurate results of radiotherapy dose calculation.
