摘要目的 对MatriXX进行调强放疗剂量验证所用机架角归零和实际机架角方法进行比较,分析两种方法得出的多角度合成通过率是否存在差异.方法 对12例头颈部肿瘤患者的调强放疗剂量分别用上述两种方式进行验证,以3 mm 3％标准进行γ通过率分析.对不同机架角下两种方式验证结果行配对t检验,对多野合成的两种方式验证结果行单因素方差分析.结果 使用实际角度方法的γ通过率比角度归零方法普遍有所下降,但80°、120°、240°时最明显,分别为98.71％与93.59％(t=2.10,P =0.000)、98.15％与93.17％(t=2.10,P =0.000)、98.94％与92.85％(t =2.10,P =0.000).多野合成的两种方式验证结果相似98.27％与94.63％ (F=0.50,P=0.134).结论 两种调强放疗剂量验证方式从两个不同立场进行,对其结论进行比较分析可更全面保障调强放疗计划验证的准确性.

abstractsObjective To explore the MatriXX measurements the dose distributions for each beam in intensity-modulated radiotherapy (IMRT) plans were measured with 0 degree gantry angle and actual gantry position respectively.To discuss whether the two multi-angle synthetic pass rate from the two methods has statistics differences.Methods The dose distributions for each beam in IMRT plans were measured with 0 degree gantry angle and actual gantry position for twelve patients with head and neck tumor respectively.The γ pass rates (according to 3％/3 mm) for each beam under each angle condition was obtained by the comparison between the measured and the calculated dose distributions from the treatment planning system which was treated as the reference distribution.Use the t-test to analyse the actual gantry angle method and use the one factor analysis of variance to analyze the two multi-angle synthetic pass rate from the two methods.Results The γ pass rates of actual gantry angle was found generally declined seemingly compared with 0 degree gantry angle,but differentγ pass rates showed only in 80 °,120°and 240° with98.71％,93.59％(t=2.10,P=0.000),98.15％,93.17％ (t=2.10,P=0.000) and 98.94％,92.85％ (t =2.10,P =0.000) respectively.The γpass rate of multi-angle synthetic was seemingly between methods (98.27％,94.63 ％,F =0.50,P =0.134).Conclusions Two kinds of IMRT verification mode are from two position to validated the IMRT plans dose accuracy,comparatively analysing the conclusions drawn from the two methods can protect accuracy of IMRT plans more comprehensively.