摘要目的 探讨配备HD-MLC的Edge加速器Eclipse模型建立与测试.方法 利用Razor、CC13采集小野百分深度剂量、离轴曲线、输出因子并与标准数据比对.使用EBT3、EPID、SRS 1000&SRS 1500测量MLC半影、穿射漏射、凹凸槽、到位准确性、DLG,并根据测试例γ通过率选出最佳DLG/透射率值.利用FC65-G对规则野、IMRT、VMAT病例行点剂量验证.使用Octavius 4D及EBT3对测试例行面剂量验证.结果 实测PDD与标准数据一致.3、4 cm射野半影较标准值小,6cm的较标准值大.所有方野左右边界、射野大小、射野中心偏差分布为-1.0～0.4 mm、0.2～ 1.7 mm、-0.3～ 1.9 mm、-0.1～0.8 mm.左、右MLC在不同位置处的半影平均值分别为(2.5±0.042)、(2.7±0.005) mm;MLC透射率分布为0.009～0.016.测得的DLG、透射因子分别为0.1861 cm、0.0116,最佳DLG、透射因子分别为0.015 cm、0.014.除1例位于低剂量区外,其余所有测试点剂量偏差均位于±3％内.IMRT面剂量验证局部、全局γ通过率分别为79.81％～ 100％、96.3％～100％(3％/3 mm),VMAT病例上述通过率分别为71.3％ ～98.9％、94.3％ ～ 99.8％.结论 本研究方法能准确地实施HD-MLC&Edge系统Eclipse模型建立与测试.

abstractsObjective To investigate the commissioning and testing of the Eclipse model of an Edge accelerator with high-definition muhi-leaf collimator (HD-MLC).Methods The percentage depth dose (PDD),profile,output factor measured by Razor and CC13 were statistically compared with the standard data.Penumbra,transmission factor (TF),leakage,concave-convex groove,accuracy of movement and dosimetry leaf gap (DLG) were measured with EBT3,electronic portal image device (EPID) and PTW SRS1000&SRS1500.The optimal DLG/TF was acquired when the γ pass rate of test cases was the highest.The point dose of regular fields,intensity-modulated radiation therapy (IMRT) and volume-modulated radiation therapy (VMAT) was verified with FC65-G.The planar dose of these case was verified with Octavius 4D and EBT3.Results The measured PDD data were consistent with the standard data.The measured penumbra of 3 cm and 4 cm square fields was smaller,whereas that of 6 cm square field was larger than the standard values.The left and right edge,field size,center of the field were distributed within the range of-1.0-0.4 mm、0.2-1.7 mm,-0.3-1.9 mm and-0.1-0.8 mm,respectively.The mean penumbra of the left and right MLC in different positions were (2.5±0.042) mm and (2.7±0.005) mm.The leakage of MLC was 0.009-0.016.The measured DLG/TF was 0.1861 cm/0.0116 and the optimal DLG/TF was 0.015 cm/0.014.The differences of point dose of all the test cases except the one which was in the low-dose area were within ±3％.Local and global γ pass rates of all IMRT were 79.81％-100％ and 96.3％-100％ (3％/3 mm),71.3％-98.9％ and 94.3％-99.8％ for VMAT cases.Conclusions This method can accurately test and commission the Eclipse treatment planning model of Edge Linac equipped with HD-MLC.