医用直线加速器的验收和射束基准数据测量  

Acceptance and Beam Reference Data Measurement of Medical Linear Accelerator

作　　者：曾华驱 汤树奎 曹剑云 黄炽雄 ZENG Huaqu;TANG Shukui;CAO Jianyun;HUANG Chixiong(Radiotherapy Center,The People’s Hospital of Gaozhou,Gaozhou Guangdong 525200,China;Cancer Center,Zhujiang Hospital of Southern Medical University,Guangzhou Guangdong 510280,China;Department of Medical Equipment,Shenzhen Hospital of Southern Medical University,Shenzhen Guangdong 518110,China)

机构地区：[1]高州市人民医院放疗中心,广东高州525200 [2]南方医科大学珠江医院肿瘤中心,广东广州510280 [3]南方医科大学深圳医院医务部设备办,广东深圳518110

出　　处：《中国医疗设备》2022年第6期53-57,84,共6页China Medical Devices

基　　金：茂名市科技立项项目[茂科字(2021)24号](2021009)。

摘　　要：目的介绍医用直线加速器的验收和射束基准数据的测量,为临床使用做准备,同时为基层医院验收新安装直线加速器提供借鉴。方法以瓦里安Trilogy直线加速器为例,测试加速器的机械性能,包括准直器旋转中心、机架旋转中心和治疗床旋转中心;射束基准数据包括百分深度剂量、横向离轴剂量分布、总输出因子和叶片透射因子,以及锥形束CT图像系统。结果准直器旋转中心、机架旋转中心、治疗床旋转中心的最大偏差分别为0.5、0.5和0.6 mm。10 cm×10 cm射野6 X FF、6 X FFF和10 X的最大剂量深度分别为1.4、1.2和2.2 cm。10 cm×10 cm限光筒射野能量为4、6、9、12、15和18 Mev的最大剂量深度为0.6、1.3、2.1、2.9、3.4和3.6 cm。6 X FF、6 X FFF和10 X的总输出因子从3 cm×3 cm到40 cm×40 cm射野分别为0.869~1.126、0.892~1.094和0.879~1.106;叶片透射因子分别是0.0151、0.0130和0.0176。锥形束CT系统性能符合厂家标准。结论通过验收和射束数据测量可以深刻了解直线加速器的性能和射束特性,有利于保证治疗计划系统建模数据准确,从而保证治疗效果和患者安全。Objective To introduce the acceptance and measurement of beam reference data of medical linear accelerator,which not only prepares for clinical use,but also provides reference for the acceptance of newly installed linear accelerator in grassroots hospitals.Methods Taking Varian Trilogy linear accelerator as an example,the mechanical properties of the accelerator were tested,including collimator rotation center,gantry rotation center,treatment table rotation center,and beam reference data,including percentage depth dose,crossline beam Profile,total scatter factors,multileaf collimator transmission factors;and CBCT.Results The maximum deviations of the rotation center of the collimator,the rotation center of the gantry,and the rotation center of the treatment table were 0.5,0.5 and 0.6 mm,respectively.The maximum dose depth of 6 X FF,6 XFFF,and 10 X under the 10 cm×10 cm field was 1.4,1.2,and 2.2 cm,respectively.the maximum dose depth of 4,6,9,12,15,18 Mev were 0.6,1.3,2.1,2.9,3.4 and 3.6 cm under 10 cm×10 cm applicator.The total output factors of 6 X FF,6 X FFF and 10 X range from 3 cm×3 cm to 40 cm×40 cm fields were 0.869 to 1.126,0.892 to 1.094,0.879 to 1.106;leaf transmission factors were 0.0151,0.0130 and 0.0176,respectively.The performance of the CBCT system conformed to the manufacturer’s standard.Conclusion Through the acceptance and measurement of the beam data,the performance and the beam characteristics of the linear accelerator can be deeply understood,and ensure the accuracy of modeling data of treatment planning system,so as to ensure the treatment effect and patient safety.

关 键 词：锥形束CT 射束测量 百分深度剂量 总输出因子 离轴剂量分布 透射因子 

分 类 号：R197.39[医药卫生—卫生事业管理]