等中心位置对脑转移瘤分次立体定向放射治疗验证计划通过率的影响  

Influence of Isocentric Location on the Passing Rate of Fractionated Stereotactic Radiotherapy Verification Plans for Brain Metastases

作　　者：彭圣贤 刘悦 Shengxian;Liu Yue(Department of Science and Education,Zigong First People's Hospital,Zigong Sichuan 643000,China;Department of Radiation Oncology,Zigong First People's Hospital,Zigong Sichuan 643000,China)

机构地区：[1]自贡市第一人民医院科教科,四川自贡643000 [2]自贡市第一人民医院肿瘤科,四川自贡643000

出　　处：《医疗装备》2022年第5期4-7,共4页Medical Equipment

摘　　要：目的研究在脑转移瘤分次立体定向放射治疗(FSRT)验证计划质控过程中,等中心位置的选择对验证计划通过率的影响。方法选取2019年1—12月在医院肿瘤科行FSRT的25例脑转移瘤患者,首先基于Eclipse v13.6放射治疗计划系统分别选择靶区中心和DICOM图像中心为等中心设计FSRT计划,其次,在OCTAVIUS模体上建立每个计划的验证计划,批准和导出验证计划并在加速器上测量每个计划的Gamma通过率,最后在VeriSoft软件上采用不同的评价方法(Max dose和Local dose)、不同的条件(10%和5%of Max dose)以及3%/3 mm和3%/2 mm两种阈值标准评估验证计划的测量结果。结果Max dose评价方法下的Gamma通过率高于Local dose评价方法下的Gamma通过率,10%of Max dose条件下的Gamma通过率高于5%of Max dose条件下的Gamma通过率,3%/3 mm阈值标准下的Gamma通过率高于3%/2 mm阈值标准下的Gamma通过率,且以靶区中心为等中心的验证计划Gamma通过率高于以DICOM图像中心为等中心的Gamma通过率,差异均有统计学意义(P<0.05)。结论在脑转移瘤FSRT验证计划质控过程中,应尽量将等中心选在靶区中心位置。Objective The influence of the selection of isocentric location on the passing rate of verification plans during the quality control of fractionated stereotactic radiotherapy(FSRT)verification plans for brain metastases was studied.Methods 25 patients with brain metastases who received FSRT in the Department of Radiation Oncology in the hospital from January to December 2019 were selected.First,based on the Eclipse v13.6 radiotherapy treatment planning system,the target volume center and the DICOM image center were selected as the isocenter to design the FSRT plan,respectively.Then the verification plan for each plan was established on the OCTAVIUS phantom.The Gamma passing rate of each plan was measured on the linear accelerator after the plans were approved and exported.Last,the measured results of verification plans were evaluated on the VeriSoft software by different evaluation methods(Max dose and Local dose),under different conditions(10% and 5% of Max dose)and two threshold standards of 3%/3 mm and 3%/2 mm.Results The Gamma passing rate using the Max dose evaluation method was higher than that of the local dose evaluation method,and the Gamma passing rate under the 10% of Max dose condition was higher than that under the 5% of Max dose condition,and the Gamma passing rate under the threshold of 3%/3 mm was higher than that under the threshold of 3%/2 mm,and the Gamma passing rate of verification plans taken the target volume center as the isocenter were higher than those taken the DICOM image center as the isocenter,and all the differences were statistically significant(P<0.05).Conclusion In the quality control process of the FSRT verification plans for brain metastases,the isocenter should be selected in the center of the target volume as far as possible.

关 键 词：脑转移瘤 分次立体定向放射治疗 Gamma通过率 等中心 

分 类 号：R815[医药卫生—放射医学]