48台医用直线加速器应用质量检测结果分析

Analysis of the Testing Results of 48 Medical Linear Accelerators Application Quality

目的对我国部分医用直线加速器进行应用质量检测 ,了解我国医用直线加速器的应用质量现状。方法对48台医用直线加速器 ,使用美国MED -TEC公司生产的CRS三维水箱检测系统和PTW公司的UNIDOS剂量仪进行检测 ,共检测性能参数包括电气联锁系统、等中心、指示误差、射线能量、射野平坦度和对称性、电子线照射时的X线污染、输出剂量精度、输出剂量稳定度、输出剂量线性等20项。结果12项机械性能参数中 ,国产加速器有10项参数合格率在80%以下 ,其中有7项参数合格率在50%以下 ,最低达26 %。而进口一手加速器除一项参数合格率为78% ,其它11项参数合格率均在80 %以上 ,进口二手机机械性能基本同国产加速器 ;8项射线性能参数中 ,国产加速器有6项参数合格率在90%以上 ,而进口一手加速器有7项参数合格率在80%以上 ,进口二手加速器的合格台数也较多。结论国产医用直线加速器和进口二手加速器的机械性能较差 ,很难满足精确放疗的需要。

Objective To test the application quality of some medical linear accelerators (L1NACs) in our country and learn the state of their application quality. Methods ACRS 3D water tank made by MED TEC company and an UNIDO S dosimeter made by PTW company are used to test 48 medical LINACs application quality. 20 performance parameters such as electronics interlock, rotation center, indicator error, beam energy, field flatness and symmetry, X ray contamination in electron beams, precision of output dose, stabilization of output dose, linearity of output dose are tested. Results Among the 12 mechanical performance parameters, for domestic LINAC, 10 parameters' qualification rate are under 80%, in which 7 parameters' qualification rate are under 50%, and the lowest qualification rate is only 26%; for first hand imported L1NAC, one parameters' qualification rate is 78%, and all the other are above 80%;the mechanical performance parameters of second hand imported L1NAC are similar to that of the domestic. Among the 8 beam performance parameters for domestic LINAC, 6 parameters' qualification rate are above 90%; for first hand imported LINAC, 7 parameters' qualification rate are above 80%,as well as second hand imported LINAC Conclusion The mechanical performance parameters of most domestic LINAC and second hand imported L1NAC are not good enough to meet the need of precision radiotherapy.