钴源后装机源强度实验测量与蒙特卡罗模拟计算的比较研究

A comparative study on the actual measurement and Monte Carlo simulation about radiation intensity of cobalt source of afterloader device

目的:针对钴源医用后装机源强度,即源空气比释动能强度进行剂量学研究。方法:分别对国内临床使用的国产GZP3型钴源后装机和德国Co0.A86型钴源后装机,采用井型电离室实验测量和基于蒙特卡罗模拟计算的方法,进行源空气比释动能强度的剂量学比较研究。结果:实验测量和蒙特卡罗模拟计算的源空气比释动能强度偏差在3.0%之内,两种型号的钴源蒙特卡罗模型得到验证。结论:基于蒙特卡罗模拟的单位源活度空气比释动能强度因子的源强度表示可应用于钴源后装机质量控制检测中,本研究建立的两种型号的钴源蒙特卡罗模型可以开展相关临床剂量学研究应用。

Objective： To carry out dosimetry study for the intensity of primal air kerma of the cobalt source of medical afterloader device. Methods： The experimental measurement of well-type ionization chamber and Monte Carlo simulation method were adopted to compare the dosimetry of primal air kerma between GZP3 of domestic afterloader device of cobalt source and Co0.a86 of Germany. Results： The deviation of intensity of primal air kerma between the experimental measurement and Monte Carlo simulation was within 3%, and the Monte Carlo models of the two types of cobalt source were verified. Conclusion： The primal intensity of intensity factor of air kerma per unit source activity based on Monte Carlo simulation can be applied in the test of quality control of cobalt source of afterloder device. The two type of Monte Carlo models of cobalt source which established in this study can be used to carry out correlatively clinical research of dosimetry.