容积弧形调强放疗计划执行时间与加速器参数的关系分析  

Analysis of relationship between VMAT plan delivery time and machine parameters

作　　者：符贵山 戴建荣 Fu Gulishan;Dai Jianrong(Deperlment of Rodiotion Oncolfgo.Natinal Camcer Center/National Clinical Research Center for Cancer/Cancer Hospital,Chinese Acudemy of Medical Sciences and Peking Union Medial Cllege.Beijing 10021,China)

机构地区：[1]国家癌症中心/国家肿瘤临床医学研究中心/中国医学科学院北京协和医学院肿瘤医院放疗科,北京100021

出　　处：《中华放射肿瘤学杂志》2024年第9期840-844,共5页Chinese Journal of Radiation Oncology

基　　金：中国医学科学院医学与健康科技创新工程项目(2023-I2M-C&T-B-076)

摘　　要：目的分析容积弧形调强放疗计划执行时间与加速器参数的关系,探索改进加速器参数以缩短治疗时间的方法.方法用简单随机方法选择2017年3月—2017年7月在中国医学科学院肿瘤医院完成容积弧形调强放疗患者的25个治疗计划,通过软件对加速器参数进行建模.分别对常规分割和大分割计划,模拟独立提高机架旋转速度、剂量率、多叶准直器(MLC)叶片速度3个加速器参数时,治疗时间的相对变化,以确定哪个参数对治疗时间的限制最强;模拟只提高限制最强的参数的速度,得到在此过程中3个参数对治疗时间限制强弱的动态变化情况.对测得的数据进行统计描述.结果对于单次剂量为2 Gy的常规分割计划,机架旋转速度是计划执行时间的主要限制因素,机架旋转速度提高超过15%时,叶片运动速度成为计划执行时间的最主要的限制因素.对于单次剂量为5 Gy的大分割计划,剂量率是计划执行时间的最主要的限制因素,剂量率提高12%以上时,机架旋转速度成为计划执行时间最主要的限制因素.结论容积弧形调强放疗计划执行时间与加速器参数的关系依赖于计划本身的特点,通过改进加速器参数来缩短计划执行时间时,要综合考虑不同机器参数及计划特点之间的关系.ObjectiveeTo analyze the relationship between volumetric-modulated arc therapy(VMAT)plan delivery time and machine parameters,aiming to exploring the methods of shortening plan delivery time by improving machine performance.Methods A total of 25 treatment plans of patients who completed VMAT in Cancer Hospital of Chinese Academy of Medical Sciences from March 2017 to July 2017 were selected by simple random sampling.The machine parameters were subject to modeling by using software.For conventional fraction and hyperfraction plans,the parameters that have the strongest limitations on delivery time were simulated by observing the relative change of delivery time in increasing the gantry speed,dose rate,multi-leaf collimator(MLC)leaf speed independently.The speed of the parameter which has the strongest limitations was simulated to obtain the dynamic changes of the limitation strength of these three parameters on the treatment time.The measured data were subject to statistical description.Results For conventional segmentation plans with 2 Gy fractional dose,the gantry speed had the strongest limitations on delivery time and the MLC leaf speed had the strongest limitations on delivery time instead when the gantry speed was increased by 15%.For hyperfraction plans with 5 Gy fractional dose,dose rate had the strongest limitations on delivery time and the gantry speed had the strongest limitations when the gantry speed was increased by 12%.Conclusions The relationship between VMAT plan delivery time and machine parameters depends on the characteristics of each plan.The relationship between different machine parameters and plan characteristics should be considered when shortening plan delivery time by improving the machine parameters.

关 键 词：放射疗法 容积弧形调强放射治疗 计划执行时间 加速器参数 

分 类 号：R312[医药卫生—基础医学]