调强放疗中的偶然误差分析及其临床应用  

Random error and its clinical application in analyzing intensity modulated radiation therapy

作　　者：王静[1] 周志孝[2] 汪琪[1] 蒋明华[1] 翟振宇[1] 

机构地区：[1]江苏省肿瘤医院放疗科,江苏南京210009 [2]上海新华医院放疗科,上海200030

出　　处：《中华肿瘤防治杂志》2009年第23期1867-1869,共3页Chinese Journal of Cancer Prevention and Treatment

基　　金：江苏省肿瘤医院重大课题基金资助项目(ZK200808)

摘　　要：目的:分析调强放疗的偶然误差及其在临床中的应用。方法:根据在验收时CT-模拟机、加速器和治疗计划系统等国际标准规定的允许误差值,运用误差理论、误差传递及均方根误差的公式,计算出调强放疗全过程中CT-模拟机、加速器上摆位、TPS计划设计和体态运动中的偶然误差。结果:偶然误差是以不可预知的偶然方式变化,是设备性能所决定,是确实存在且无法消除的,存在于整个调强放疗的全过程,其误差在△=±2.55～±4.27mm范围内,均值为3.4mm。结论:临床医生勾画靶区时,必须外放1～2△即3.4～6.8mm的边界范围,胸腹病例可考虑放3△的边界即10.2mm,可以使误差最小,从而避免靶区漏照。OBJECTIVE： To study the random error and its clinical application in analyzing intensity modulated radiation therapy （IMRT）. METHODS： According to permissive errors of international standard in CT-simulator, accelerator and TPS planning system in acceptance, appling error theory, and error propagation and root-meansquare calculation formula, the random errors used in CT-simulator positioning, accelerator set up, TPS planning design and body movement in all process of IMRT were eaculated. RESULTS： The random errors were determined by equipment performance and could not be dismissed. The random errors in all the process of IMRT were within △ =±2.55-±4.27 mm and the average value was 3.4 mm. CONCLUSIONS： Clinically doctors should determine PTV by setting up 1-2△ （3.4- 6. 8 mm） respectively after confirming CTV. In some special cases, it could be 3△ （10.2 mm）. In this way it has minimized errors and secure covering of isodose surface around the target.

关 键 词：调强放疗 偶然误差 边界 临床应用 

分 类 号：R730.5[医药卫生—肿瘤]