国产外置式自动多叶准直器控制设计及其临床性能测试分析  

A Design of Domestic External Automatic Multi Leaf Collimator Automatic Control and the Performance Analysis in Clinical

作　　者：陈婷婷 钟睿[2] 孙官清[2] 柏森[3] 

机构地区：[1]成都市妇女儿童中心医院心血管科,成都610000 [2]四川大学原子核科学技术研究所辐射物理及技术教育部重点实验,成都610064 [3]四川大学华西医院放疗科,成都610041

出　　处：《中国医学物理学杂志》2014年第2期4776-4781,4819,共7页Chinese Journal of Medical Physics

基　　金：发改委高科技[2006](1089号)

摘　　要：目的:设计一款高位移精度的国产外置式医学用自动多叶准直器(Multi Leaf Collimator,简称MLC),同时验证和测试该MLC在放射治疗临床使用中的辐射野精度、半影、漏射率、适形度等重要指标数据。方法:控制设计方面,采用直流电机模糊控制算法、位移精度控制、漏射优化等关键方案实现MLC的核心功能。测试方面采用60Co治疗机作为放射源,国产MLC形成射野,使用三维水箱系统和二维剂量探测器对剂量分布进行测量,并根据测量结果计算MLC性能指标数据。结果:射野数字指示与辐射野精度误差测试中,在叶片运动方向上位移误差在0.2 mm^1.6 mm之间;漏射率测试中,最大漏射率小于2%;半影测试中,半影随射野增大而增大,在10 cm×10 cm射野时,叶片运动方向半影为8.6 mm;适形度测试中,MLC形成射野和TPS定制适形度值在99.7%以上。结论:国产外置式MLC各项指标符合食药总局检验标准,完全满足临床治疗需求。Objective： Design a high movement precision domestic external automatic multi-leaf collimator, and measurement the accuracy, leakage reflectivity, conformal and other key parameters of MLC. Methods： In control, use DC motor fuzzy control algorithm, the displacement accuracy control, and the optimization of radiation leakage methods to realize the core fimction of MLC. In measurement, use ^60Co therapy unit as the source, MLC form the field, and use 3D water tank and 2D dose detector measurement the distribution dose, then calc the key parameters. Results： In the error test of radiation field and the digital indication, the displacement error is between 0.2 mm-l.6 mm; In the test of leak rate, the maximum leakage radiation is less than 2%; In the penumbra test, penumbra increases with the radiation field, when radiation field is 10 cmxl0 cm, the penumbra is 8.6 mm; In the conformal test, the conformal value of MLC radiation field and TPS customized is 99.7%. Conclusions： Domestic external MLC indicators fully satisfy clinical needs.

关 键 词：多叶光栅 模糊控制 射野 剂量 漏射率 

分 类 号：R135[医药卫生—劳动卫生]