Pinnacle计划系统调强放疗验证Gamma通过率的研究

A Result Analysis of Gamma Pass Rates for IMRT Verification for Pinnacle Planning System

目的通过分析Pinnacle计划系统调强放疗(IMRT)验证Gamma通过率的结果,探讨Pinnacle计划系统参数对调强验证通过率的影响。方法本研究在Pinnacle计划系统中导入Xio系统完成的5例头颈调强放射治疗计划,使用不同的计算间隔和输出间隔分别输出等中心处3个正交解剖平面的剂量分布,以Xio系统中对应平面的剂量分布作为参考剂量分布用于模拟测量结果,在Mapcheck软件中进行Gamma通过率计算。结果 3种不同算法和计算间隔间的Gamma通过率存在显著差异。结论Pinnacle计划系统参数可能会对调强验证Gamma通过率产生影响,直接引用文献中的Gamma通过率指标作为调强验证体系的判断标准值得讨论。

Objective The study was to explore effort of planning parameters by analyzing the result of Gamma pass rates for IMRT verification for Pinnacle planning system. Methods 5 Head Neck IMRT plans finished by Xio planning system were imported into Pinnacle planning system. Different algorithms and calculation grids were used to calculate the dose distributions for 3 orthogonal planes at isocenter which were exported in 3 kind grids. Mapcheck software was used to calculate the Gamma pass rate using the plane dose distributions from Xio system as the reference ones simulating the measurements. Result The difference of Gamma pass rates for 3 kinds of algorithm and calculation grids were of statistical significance. Conclusion The parameters in Pinnacle planning system may have influence on Gamma pass rates. It needs further discussion to directly use the Gamma pass rates in documents during the establishing of IMRT QA protocol.