无均整器模式对宫颈癌放射治疗剂量的影响  

EFFECT OF FLATTENING FILTER-FREE MODE ON THE THERAPEUTIC DOSE OF RADIOTHERAPY FOR CERVICAL CAN-CER

作　　者：王惠 姜召峰 杨敬磊 车帅 黄显玉 张宗春 WANG Hui;JIANG Zhaofeng;YANG Jinglei;CHE Shuai;HUANG Xianyu;ZHANG Zongchun(Department of Radiophysics, Qingdao Central Hospital, Qingdao 266042, China)

机构地区：[1]青岛市中心医院放射物理科,山东青岛266042

出　　处：《精准医学杂志》2021年第5期453-455,459,共4页Journal of Precision Medicine

摘　　要：目的通过比较均整器模式容积旋转调强放射治疗(FF-VMAT)和无均整器模式容积旋转调强放射治疗(FFF-VMAT)两种放疗方式在宫颈癌中的剂量分布,探讨有无均整器对放疗剂量的影响。方法选取青岛市中心医院2019年1—8月35例宫颈癌患者,每例患者分别设计FF-VMAT和FFF-VMAT两种放疗方式,均采用eclipse计划系统,在系统中除分别采用FF和FFF两种模式外,其他参数设置均相同。分别对两种计划的靶区剂量和危及器官剂量进行评估和比较;将两种放疗方式分别在加速器上模拟运行比较运行效率。结果FF-VMAT与FFF-VMAT两种放疗方式进行比较,靶区剂量评估中靶区2%体积对应的剂量(D2%)及靶区剂量均匀性指数(HI)、适形度指数(CI)、剂量梯度平均距离(GM)具有显著差异(t=3.43~5.46,P<0.05),D98%无显著差异(P>0.05),危及器官剂量评估中仅直肠Dmean和小肠Dmax比较具有显著差异(t=2.81、2.84,P<0.05),运行效率比较仅加速器跳数有显著差异(t=28.46,P<0.05)。结论FF-VMAT和FFF-VMAT两种放疗方式均能满足临床需求,但在剂量分布方面FF-VMAT较FFF-VMAT更优。Objective To investigate the dose distribution of flattening filter volumetric modulated arc therapy(FF-VMAT)versus flattening filter-free volumetric modulated arc therapy(FFF-VMAT)as radiotherapy for cervical cancer,as well as the effect of the presence or absence of flattening filter on radiotherapy dose.Methods A total of 35 patients with cervical cancer in Qingdao Central Hospital from January to August 2019 were enrolled,and FF-VMAT and FFF-VMAT radiotherapy plans were designed for each patient.The eclipse planning system was used,and all parameters except FF and FFF modes remained the same.The two plans were compared in terms of target dose and the dose of organs at risk,and simulation run of the two modes was performed on an accelerator to compare running efficiency.Results As for target dose parameters,there were significant diffe-rences between FF-VMAT and FFF-VMAT in the dose corresponding to 2%of the target volume,uniformity index,conformity index,and mean distance of dose gradient(t=3.43-5.46,P<0.05),and there was no significant difference in D98%(P>0.05).As for dose parameters of organs at risk,there were significant differences between FF-VMAT and FFF-VMAT in rectum Dmean and intestine Dmax(t=2.81,2.84,P<0.05).Comparison of running efficiency showed a significant difference in the number of monitor units(t=28.46,P<0.05).Conclusion Both FF-VMAT and FFF-VMAT can meet clinical needs,but FF-VMAT is better than FFF-VMAT in dose distribution.

关 键 词：宫颈肿瘤 放射疗法 调强适形 容积旋转调强 无均整器模式 剂量分布 危及器官剂量 剂量效应关系 辐射 算法 

分 类 号：R737.33[医药卫生—肿瘤] R815[医药卫生—临床医学]