颅内多发转移瘤立体定向放射治疗计划质量保证测试例应用研究  

Quality assurance test cases for stereotactic radiation therapy planning of multiple intracranial metastases

作　　者：孟祥银 于浪 李文博 汪之群 连欣 王嘉欣 孙显松 冷凌萱 杨波 邱杰 Meng Xiangyin;Yu Lang;Li Wenbo;Wang Zhiqun;Lian Xin;Wang Jiaxin;Sun Xiansong;Leng Lingxuan;Yang Bo;Qiu Jie(Department of Radiation Oncology,Peking Union Medical College Hospital,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100730,China)

机构地区：[1]中国医学科学院,北京协和医学院北京协和医院放射治疗科,北京100730

出　　处：《中华放射医学与防护杂志》2025年第1期31-36,共6页Chinese Journal of Radiological Medicine and Protection

基　　金：国家重点研发计划项目(2022YFC2404606);中央高水平医院临床科研业务费资助项目(2022-PUMCH⁃B-116)。

摘　　要：目的提出一组具有临床代表性的颅内多发转移瘤立体定向放射治疗(SRT)计划质量保证测试例,用于评估该技术的计划质量与机器执行能力。方法根据多发脑转移瘤的临床特点,设计4组测试例:3、6、9靶区和危及器官(OAR)测试例。基于以上测试例进行SRT计划设计,评估适形度指数(CI)、梯度指数(GI)、均匀性指数(HI)与正常脑组织受量即Brain⁃PTV被24 Gy的剂量线包裹的体积(V24 Gy),设计每个测试例对应的验证计划,分别进行点剂量、平面剂量(PD)和半导体矩阵平面剂量(SRS MapCHECK,SMC)验证,与治疗计划系统(TPS)计算结果对比,平面剂量的γ分析标准取1 mm/2%和2 mm/2%。结果3、6、9靶区和OAR测试例SRT计划的平均CI、GI、HI与Brain⁃PTV分别为1.04±0.03、3.79±0.40、0.73±0.01和(7.46±3.80)cm 3;点剂量平均偏差分别是0.88%±0.98%、1.47%±0.79%、1.52%±0.76%和1.17%±0.38%;PD单野γ通过率,在2 mm/2%的标准下,平均值均>98%,在1 mm/2%的标准下,平均值均>96%;SMC半导体矩阵的平均γ通过率在1 mm/2%和2 mm/2%的标准下依次为97.75%±2.31%和99.33%±0.62%。结论本研究提出的颅内多发转移瘤立体定向放射治疗计划质量保证测试例可以有效地评估该技术的计划质量与机器执行能力,能够辅助各中心进行临床应用。Objective To present a set of clinically representative quality assurance(QA)test cases for stereotactic radiosurgery(SRT)plans of multiple intracranial metastases,in order to assess the plan quality and machine execution capabilities.Methods Based on the clinical characteristics of multiple brain metastases,four groups of test cases with three target volumes(TVs),six TVs,nine TVs,and TVs near organs at risk(OARs)were designed.For these cases,SRT plans were developed,and plan quality was assessed using metrics including the Radiation Therapy Oncology Group conformality index(RTOG CI),gradient index(GI),homogeneity index(HI),and the volume of normal brain tissue receiving a dose of 24 Gy(V24 Gy),which was defined as the volume enclosed by the 24 Gy isodose line around the Brain⁃PTV(V24 Gy of Brain⁃PTV).Verification plans were generated for each test case,including the verification of point doses,planar doses(PD),and SRS MapCHECK(SMC)semiconductor matrix planar doses.Compared with the calculated result of the treatment planning system(TPS),the criteria for theγanalysis of planar doses were set at 1 mm/2%and 2 mm/2%.Results For the four groups of test cases,the mean CI,GI,HI,and V24 Gy of Brain⁃PTV were 1.04±0.03,3.79±0.40,0.73±0.01 and(7.46±3.80)cm 3,respectively.The mean deviations of the point doses were 0.88%±0.98%,1.47%±0.79%,1.52%±0.76%,and 1.17%±0.38%,respectively.The meanγpassing rates of the single fields for PDs were greater than 98%at 2 mm/2%and exceeding 96%at 1 mm/2%,and the meanγpass rates of the SMC semiconductor matrix for PDs were 97.75%±2.31%and 99.33%±0.62%,at 1 mm/2%and 2 mm/2%respectively.Conclusions The proposed QA test cases for SRT of multiple intracranial metastases allow for the effective assessments of the plan quality and machine execution capabilities and,thus,can assist various centers in clinical applications.

关 键 词：颅内多发转移瘤 立体定向放射治疗 测试例 

分 类 号：R739.41[医药卫生—肿瘤]