【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。更多还原

【Abstract】 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 function 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~1.6 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 cm×10 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.更多还原