GZP3钴-60近距离治疗源剂量学参数的蒙特卡洛计算  

Monte Carlo calculation of dosimetric parameters of GZP3 ^(60)Co brachytherapy source

作　　者：龙凤翔[1] 许安建[2] 雷琴[1] 吴骏翔 黄静[1] 勾成俊[1] 侯氢[1] 吴章文[1] 

机构地区：[1]四川大学核科学与技术学院教育部辐射物理与技术重点实验室,四川成都610065 [2]中国核动力研究设计院,四川成都610005

出　　处：《中国医学物理学杂志》2017年第2期115-120,共6页Chinese Journal of Medical Physics

基　　金：国家重点研发计划(2016YFC0105103)

摘　　要：根据美国医学物理协会TG-43报告的建议,应用蒙特卡洛程序GEANT4,针对中国核动力研究设计院推出的GZP3型腔内后装治疗机,模拟计算并得到了其钴-60(^(60)Co)后装源的剂量学参数。在计算中,分别在径向方向和不同的各项异性方向上设定了16个计数点,并且在每个计数点放置了一个探测器用来收集源发射的粒子能量。对于大于1 cm的各项异性距离,探测器的体积要比靠近源处的探测器体积大10倍。经过一系列的计算,我们得到了剂量率常数、径向剂量函数值和各项异性函数值,并对剂量率常数、径向剂量函数值以及各项异性函数值等数据进行了相关的比较分析,然后将它的径向剂量函数值和各项异性函数值与相应的Flexisource ^(60)Co源、GZP6源做了比较,比较结果用图表列举出来,其中GZP3源的剂量率常数的模拟值为(1.100±0.05)c Gy·h^(-1)·U^(-1)。这一剂量学参数,在临床上可以用来作为三维近距离放射治疗计划系统的输入参数。According to the recommendations of the American Association of Physicist in Medicine Task Group 43, Monte Carlo program GEANT4 is used to simulate and calculate the dosimetric parameters of GZP3 ^60Co brachytherapy source of the GZP3 cavity after loader designed by Nuclear Power Institute of China. In the calculations, we set 16 counting points in the radial direction and different anisotropy directions, respectively, and place a detector at each point to collect the energy of the particles emitted by the source. For the anisotropy distance which is more than 1 cm, the volume of the detectors is ten times larger than that of the detectors near the source. After a series of calculations, the dose rate constant, radial dose function values and anisotropy function values were obtained, and the dose rate constants, radial dose functions and anisotropy functions were comparatively analyzed. The compared results about the radial dose functions and the anisotropy functions among GZP3 ^60Co,Flexisource60Co and GZP6 ^60Co were presented in charts. The simulated value of dose rate constant of GZP3 source was（1.100±0.050） c Gyh^-1·U^-1. The dosmistric parameters of GZP3 ^60Co source can be used as input parameters of three-dimensional brachytherapy radiation therapy planning system in clinic.

关 键 词：钴-60 近距离治疗 蒙特卡洛计算 GEANT4 剂量参数 

分 类 号：R811.1[医药卫生—放射医学]