Eclipse计划系统2种算法下的非均匀组织深度剂量差异研究  

Study on depth dose difference for inhomogeneous tissue with two algorithms of Eclipse planning system

作　　者：吴哲 庞亚 彭圣贤 徐程 WU Zhe;PANG Ya;PENG Sheng-xian;XU Cheng(Department of Radiotherapy,Zigong First People's Hospital,Zigong 643000,Sichuan Province,China;Department of Radiotherapy,Beijing Luhe Hospital of Capital Medical University,Beijing 101149,China)

机构地区：[1]自贡市第一人民医院放疗室,四川自贡643000 [2]首都医科大学附属潞河医院放疗科,北京101149

出　　处：《医疗卫生装备》2022年第5期50-53,59,共5页Chinese Medical Equipment Journal

基　　金：四川省卫健委课题(20PJ272)。

摘　　要：目的:比较6和10 MV X射线下先进外照射光子剂量(Acuros XB,AXB)算法和各向异性解析算法(aniso-tropic analytical algorithm,AAA)计算的非均匀组织的百分深度剂量差异。方法:在Eclipse计划系统中创建30 cm×30 cm×30 cm的水模体,在模体3 cm深度处依次加入深度为3 cm的肺组织、骨组织、空气和聚四氟乙烯(poly tetra fluoroethylene,PTFE),构建水-肺-水、水-骨-水、水-空气-水、水-PTFE-水4种非均匀组织模型。分别使用6和10 MV X射线照射,比较AXB和AAA 2种算法计算的非均匀组织的百分深度剂量。采用SPSS 22.0软件进行统计学分析。结果:在3~6 cm深度非均匀组织界面处形成明显的二次剂量建成效应。在水-肺-水组织中,6 MV X射线下2种算法计算的百分深度剂量差异最大达到4.82%,10 MV X射线下差异最大达到3.32%;在水-骨-水组织中,6 MV X射线下差异最大达到3.74%,10 MV X射线下差异最大达到3.65%;在水-空气-水组织中,6 MV X射线下差异最大达到25.15%,10 MV X射线下差异最大达到25.98%;在水-PTFE-水组织中,6 MV X射线下差异最大达到13.47%,10 MV X射线下差异最大达到13.09%。在非均匀组织中,2种算法计算的剂量差异有统计学意义(P<0.05)。结论:6和10 MV X射线下,2种算法计算的水-肺-水和水-骨-水组织的剂量差异较小,水-空气-水和水-PTFE-水组织的剂量差异较大。Objective To compare the percentage depth dose characteristics of the inhomogeneous tissue calculated with Acuris XB(AXB)algorithm and anisotropic analytical algorithm(AAA)at 6 and 10 MV X-rays.Methods A 30 cm×30 cm×30 cm water phantom was built in the Eclipse planning system,and several inhomogeneous tissues including water-lung-water tissue,water-bone-water tissue,water-air-water tissue and water-poly tetra fluoroethylene(PTFE)-water tissue,were created sequentially at a depth of 3 cm in the phantom by adding homogeneous tissues of 3 cm thickness such as lung tissue,bone tissue,air and PTFE.The percent depth doses of the inhomogeneous tissues calculated by AXB and AAA algorithms were compared under 6 and 10 MV X-ray irradiation.SPSS 22.0 software was used for statistical analysis.Results A significant secondary dose build-up effect was formed at the inhomogeneous tissue interface at 3-6 cm depth.In water-lung-water tissue,the maximum difference in percent depth dose calculated by the 2 algorithms reached 4.82%for 6 MV X-rays and 3.32%for 10 MV X-rays;in water-bone-water tissue,the maximum difference was 3.74%for 6 MV X-rays and 3.65%for 10 MV X-rays;in water-air-water tissue,the maximum difference was 25.15%for 6 MV X-rays and 25.98%for 10 MV X-rays;in water-PTFE-water tissue,the maximum difference was 13.47% for 6 MV X-rays and 13.09%for 10 MV X-rays.AXB and AAA algorithms had significantly statistical differences when used for calculating the dose differences of the inhomogeneous tissues(P<0.05).Conclusion At 6 and 10 MV X-rays AXB and AAA algorithms have low dose differences for water-lung-water and water-bone-water tissues while high ones for water-air-water and water-PTFE-water tissues.

关 键 词：Eclipse计划系统 均匀组织 非均匀组织 百分深度剂量 AXB算法 AAA 

分 类 号：TP18[自动化与计算机技术—控制理论与控制工程] R730.55[自动化与计算机技术—控制科学与工程]