摘要
目的联合应用两种商用及一种自行开发的基于加速器轨迹日志(LFB)的三维剂量重建系统验证肺癌VMAT计划。方法编程实现读取TrueBeam轨迹日志中误差并导入计划系统生成重建剂量。选18例肺癌双弧VMAT计划,用ArcCheck测量并利用3DVH重建,同时使用LFB和Compass计算模式重建。其中5例4 h内由ArcCheck测2次,检测加速器重复性。将18例计划移植到建成5 cm、背散4 cm、中心放置有FC65-G电离室的固体水模上计算电离室平均剂量并与实测及3种重建系统重建点剂量比对。结果加速器重复性稳定。LFB、3DVH、Compass及FC-65 G实测与计划点剂量偏差≤2%。ArcCheck曲面二维,3DVH、Compass整体及LBF所有器官三维γ通过率在所有比对标准下均>90%,3DVH及Compass个别器官γ通过率低。重建剂量与原计划相比,LBF差异最小,除肺之外器官Compass差异居中、3DVH最大。结论LBF、3DVH、Compass 3种系统能从不同方面反映肺癌VMAT剂量验证结果,联合应用三者进行剂量验证能更直观的展现出验证结果,便于后续分析。
Objective To evaluate the combined effect of an trajectory log field based(LBF)and two commercial dose reconstruction systems on volume-modulated arc therapy(VMAT)dose verification of lung cancer.Methods An in-house program was developed to introduce errors in trajectory log of TrueBeam to the origin plan and recalculate the dose of the error plan in treatment planning system(TPS).A total of 18 lung cancer cases treated by two-arc VMAT were selected to perform on LINAC and measured by ArcCheck simultaneously.Then,the reconstructed doses were obtained by 3DVH.The mode of reconstruction was calculated by LFB and Compass.Five of the 18 cases were performed on LINAC two times in four hours and measured by ArcCheck to evaluate the stability of the TrueBeam performance.The 18 plans were recalculated and performed on LINAC with a solid water phantom with 5 cm build-up,4 cm back scattering thickness and a FC65-G detector in the center.The measured dose by detector was compared with the reconstructed dose by three systems.Results TheTruebeam performance was stable.For all of the 18 cases,the point dose measured by FC65-G and reconstructed by three systems had a deviation of less than 2%to the TPS calculated.For all of the organs reconstructed by LBF and most organs reconstructed by 3DVH and Compass,theγpass rate between them and TPS all exceeded 90%under all criteria,as well as the ArcCheck measured results.For all the organ dose difference between reconstructed and TPS,LBF system had the smallest difference,followed by the Compass system except the lung,and the 3DVH had the highest difference.Conclusions LBF,3DVH and Compass can reflect the VMAT dose verification results of lung cancer from different perspectives.The combined application of three systems can demonstrate the verification results in an intuitive manner,which is beneficial for subsequent analysis.
作者
马阳光
麦日珍
裴运通
胡金炎
孔凡洋
王学敏
郭跃信
Ma Yangguang;Mai Rizhen;Pei Yuntong;Hu Jinyan;Kong Fanyang;Wang Xuemin;Guo Yuexin(Department of Radiation Oncology,The First Affiliated Hospital of Zhengzhou University,Zhengzhou 450052,China;Department of Medical Equipment,The First Affiliated Hospital of Zhengzhou University,Zhengzhou 450052,China;Department of Radiotherapy Hospital Unit Radiation Therapy,Shaanxi Provincial Tumor Hospital,Xi′an 710061,China)
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2021年第1期76-80,共5页
Chinese Journal of Radiation Oncology
基金
河南省高等学校重点科研项目计划(19B416005)
河南省科技厅科技攻关计划(182102310369)
陕西省卫生健康科研基金项目(2018A007)。
关键词
三维剂量重建
轨迹日志重建
三维γ分析
剂量体积直方图
剂量验证
Three-dimensional dose reconstruction
Trajectory-log reconstruction
Three-dimensional gamma analysis
Dose volume histogram
Dosimetry verification
