摘要
目的:基于ESAPI与可视化脚本,评估分析射束形态控制器(ASC)算法在鼻咽癌容积调强放射治疗中的应用。方法:对40例鼻咽癌患者的临床资料做回顾性分析,采用Eclipse v15.5计划系统为每位患者制定6组容积调强放射治疗计划,分别为对照组(ASC-no)、实验Ⅰ组(ASC-verylow)、实验Ⅱ组(ASC-low)、实验Ⅲ组(ASC-moderate)、实验Ⅳ组(ASC-high)和实验Ⅴ组(ASC-veryhigh),且所有计划的优化参数均相同。采用Eclipse v15.5内置可视化脚本与ESAPI,评估各组计划之间的靶区与危及器官剂量学差异,进一步分析射束孔不规则度与计划复杂度的变化。结果:相比照组(ASC-no),实验组PGTV69的适形度指数未有统计学差异;而实验组PGTV69和PCTV1的均匀性指数(HI)均存在统计学差异(P<0.05),且随着ASC权重的增大,差异呈现增加趋势;对于PCTV2的HI,实验组中II组、III组和IV组存在统计学差异(P<0.05)。与对照组相比,脊髓Dmax、喉Dmean、左侧腮腺Dmean仅V组存在统计学差异(P<0.05);I组的脑干Dmax存在统计学差异(P<0.05);II组的右侧腮腺V30存在统计学差异(P<0.05);I组和V组的晶状体Dmax存在统计学差异(P<0.05);III组、IV组和V组的垂体Dmax存在统计学差异(P<0.05)。此外,实验组计划中,I组和II组间的总机器跳数存在统计学差异(P<0.05)。随着通ASC权重值的增加,计划复杂度与射束孔不规则度均呈现降低趋势。结论:ASC算法改善了计划复杂度和射野不规则度。其中,低权重ASC降低计划执行机器跳数,高权重ASC影响靶区均匀性以及其他剂量学指标。综合考虑计划质量和投照效率,对于鼻咽癌类型的复杂放疗计划,建议ASC权重设置为verylow、low和moderate。
Objective To analyze and evaluate the application of aperture shape controller(ASC)algorithm in volumetric modulated arc therapy(RapidArc)for nasopharyngeal carcinoma based on ESAPI and visual scripting.Methods The clinical information of 40 patients with nasopharyngeal carcinoma was analyzed retrospectively,and Eclipse v15.5 treatment planning system was used to design 6 RapidArc plans for each patient.The 6 groups of plans included control group(ASC-no),experimental groupⅠ(ASC-verylow),experimental groupⅡ(ASC-low),experimental groupⅢ(ASC-moderate),experimental groupⅣ(ASC-high)and experimental groupⅤ(ASC-veryhigh),and the other optimization parameters of all plans were set as the same.The ESAPI and visual scripting of Eclipse v15.5 were used to assess the dosimetric differences in target areas and organs-at-risk and further analyze the variations of aperture irregularity and plan complexity index.Results No statistical difference was found in the conformity index of PGTV69 between control group and experimental groups,but the homogeneity index(HI)of PGTV69 and PCTV1 in experimental groups was higher than that in control group,with statistical differences(P<0.05),and the difference in HI showed an increasing trend with the increase of ASC weight.For the HI of PCTV2,there were statistical differences between control group and experimental groups II,III and IV(P<0.05).Compared with the dosimetric parameters of organs-at-risk in control group,there were statistical differences in the Dmaxof spinal cord,the Dmeanof larynx and parotid-L in experimental group V(P<0.05);the Dmeanof brainstem in experimental group I(P<0.05);the V30 of parotid-R in experimental group II(P<0.05);the Dmean of lens in experimental groups I and V(P<0.05);and the Dmaxof pituitary in experimental groups III,IV and V(P<0.05).Among the experimental groups,there was statistical differences in total machine monitors between experimental group I and experimental group II(P<0.05).As the ASC weight increasing,both aperture irregularity and plan complexity index showed a decreasing trend.Conclusion ASC algorithm improves plan complexity index and aperture irregularity.Among them,the ASC of low weight reduces machine monitors,and the ASC of high weight affects the homogeneity of target areas and other dosimetric indicators.Based on the comprehensive consideration of plan quality and delivery efficiency,the ASC weight is recommended to be set as verylow,low and moderate for nasopharyngeal carcinoma and other complex radiotherapy plans.
作者
朱皓
贾晓斌
朱伟华
张震
韩增伟
ZHU Hao;JIA Xiaobin;ZHU Weihua;ZHANG Zhen;HAN Zengwei(Clinical Application Training Department of Varian Medical Systems,Inc.,Beijing 102600,China;Department of Radiotherapy,the Ninth People's Hospital Affiliated to Shanghai Jiaotong University School of Medicine,Shanghai 201900,China)
出处
《中国医学物理学杂志》
CSCD
2020年第5期545-551,共7页
Chinese Journal of Medical Physics
关键词
鼻咽癌
容积调强放射治疗
射束形态控制器
可视化脚本
射束孔不规则度
计划复杂度
nasopharyngeal carcinoma
volumetric modulated arc therapy
aperture shape controller
visual scripting
aperture irregularity
plan complexity index
作者简介
共同第一作者:朱皓,硕士,中级临床培训工程师,研究方向:肿瘤放射物理及放射剂量学,E-mail:Hao.Zhu@varian.com;共同第一作者:贾晓斌,研究方向:放射物理与医学影像,E-mail:1337643544@qq.com。
