摘要目的 研究低熔点合金铅补偿器在临床调强放疗中的应用价值.方法 用计划系统输出射野强度分布文件(Dicom RT),通过测定低熔点合金铅衰减因子计算出Dicom RT文件对应射野中每个像素对应的加工深度,产生用于AUTIMO 3D数控切割机的控制文件,然后使用加工好的泡沫浇铸低熔点合金铅成型,产生调强放疗所需补偿器并通过MatriXX的质量控制测试系统对其检测.同时随机对比了10例患者多叶准直器和低熔点合金铅补偿器调强放疗的测试结果.结果 治疗中心点剂量和面剂量显示使用低熔点合金铅补偿器调强放疗能产生和计划系统基本相同的剂量分布,误差在5％以内且临床可接受.与多叶准直器相比,低熔点合金铅补偿器调强放疗所需放疗时间少[(4.44±0.39) min:(5.71±0.57) min (t=10.82,P=0.000)]、机器跳数少[(462.5±65.8)MU:(524.5±99.6) MU (t=3.14,P=0.012)].结论 铅补偿调强放疗技术相比于MLC的独特优势在于临床上有重要推广价值,为广大基层医院在低成本条件下开展精确放疗提供了一套可行方法.

abstractsObjective To study the using of cerrobase as the compensation material in the intensitymodulated radiation therapy (IMRT) implementation and impact factors.Methods With therapy planning system (TPS) exported the radiation field intensity file (Dicom RT),through measuring the attenuation coefficient of cerrobase,to calculate the processing depth of AUTIMO 3D CNC corresponding for Dicom RT files at each pixel,then using the processed foam casting of Cerrobase,produced the required IMRT compensator.Through the MATRIXX testing the IMRT compensator in clinical implementation.At the same time we compared the MU of using multi-leaf collimator (MLC) and Cerrobase IMRT compensator for 10patients.Results With cerrobase compensation IMRT can get similar dose or dose distribution to dose produced by TPS for point or plane dose,error is within 5％.To comparison with MLC,using cerrobase compensator has fewer treatment times ( (4.44±0.39) min:(5.71±0.57) min (t =10.82,P =0.000) )and fewer MU (462.5 ± 65.8) MU:(524.5±99.6) MU(t=3.14,P=0.012) ).Conclusions Comparison with MLC IMRT,the cerrobase compensation technique has an important application value with its unique advantages.This research provides an implemented method of IMRT radiotherapy for the primaryhospital.