机器性能检查系统在加速器的应用评估  

Evaluation of machine performance check(MPC)system in accelerator

作　　者：肖杨 黄顺平[1] 李恒 吴艳[1] 张雅倩 陈兴强 Xiao Yang;Huang Shunping;Li Heng;Wu Yan;Zhang Yaqian;Chen Xingqiang(Cancer Centre,Second Affiliated Hospital of Chongqing Medical University,Chongqing 410000,China)

机构地区：[1]重庆医科大学附属第二医院肿瘤中心,410000

出　　处：《中华放射肿瘤学杂志》2021年第6期598-601,共4页Chinese Journal of Radiation Oncology

摘　　要：目的验证Varian公司TrueBeam系列加速器机器性能检查(MPC)系统的可靠性、精确度与稳定性。方法装机完成后通过验收数据与第1次MPC运行的结果进行比较,验证MPC结果可靠性;通过人为引入误差的方法验证MPC结果在图像引导放疗应用中的精确度。收集2019—2020年间60组MPC部分结果求,比较各指标稳定性差异。结果MPC获得的设备误差参数均低于验收获得的误差参数,两者数据差异最大仅为2mm且占阈值比<20%。MPC对辐射和成像位置偏移的感应精度较高,r值均>90%;其中治疗床Vertical方向对位移精度感应较差,r值<73.7%。对于此次验证指标稳定性最好的为治疗床角度方向,标准差均≤0.01,其余各指标稳定性差异不大。结论MPC可以作为图像引导放疗常规质量保证的一种验证工具,对于辐射、成像等中心的验证精度优于机架、准直器和治疗床的机械精度。Objective To verify the reliability,accuracy and stability of the machine performance check(MPC)system of Varian′s TrueBeam series accelerator.Methods After the installation was completed,the acceptance data were compared with the results of the first MPC operation to verify the reliability of the MPC results;the accuracy of the MPC results in the image-guided radiotherapy(IGRT)application was verified by the method of artificially introducing errors.The mechanical performance results of 60 groups of MPC from March 2019 to March 2020 were collected to calculate the mean value and standard deviation and compare the stability differences of each index.Results The equipment error parameters obtained by MPC were all lower than those obtained by acceptance.The maximum difference between two sets of data was only 2mm and the threshold ratio was less than 20%.MPC had a high sensing accuracy for radiation and imaging position shift,and the r values were more than 90%.The vertical direction of the couch had a poor sense of displacement accuracy,and the r value was less than 73.7%.For this verification project,the angle of the treatment bed was the most stable,and the standard deviation did not exceed 0.01.The stability of other indexes did not significantly differ.Conclusions MPC can be used as a verification tool for routine quality assurance of IGRT.The verification accuracy of radiation and imaging centers are better than the mechanical accuracy of gantry,collimator and couch.

关 键 词：机器性能检查 可靠性 精确度 稳定性 

分 类 号：R730.55[医药卫生—肿瘤]