自动计划RapidPlan优化模块在鼻咽癌调强计划中的可行性应用

摘要

Objective To evaluate the feasibility of automatic plan using RapidPlan model in the intensity-modulated radiotherapy (IMRT) plan for nasopharyngeal carcinoma (NPC) by comparing the differences between automatic and conventional plans.Methods The specific features from 60 high-quality plans for NPC were analyzed and extracted to establish an automaticoptimization model,RapidPlan model.Another 15 NPC plans were used to test the established RapidPlan model.After the model testing and optimization,automatic plans for the 15 patients with NPC were generated.The differences between automatic plans and conventional plans were compared.The statistical significance was analyzed using paired sample t-test of SPSS 22.0.Results The dose distributions observed from the automatic plans using RapidPlan model were better than those obtained using conventional plan.Compared with conventional plan,the automatic plans using RapidPlan model shortened the average optimization time by 33.67％ (P=0.000).The average monitor unit was reduced by 376 MU in automatic plans using RapidPlan model,which was 14.8％ reduction compared to that in conventional method (P=0.000).Conclusion The automatic optimization model based on anatomical features and priori knowledge,RapidPlan model,was used to establish optimization model and set up the optimization parameters,and to finally generate automatic IMRT plan for PNC.The automatic plan provided better dose coverage in target areas with lower dose to normal tissues,reduced plan optimization time,and improved delivery efficiency,compared with conventional IMRT plan.The automatic plan using RapidPlan model is feasible in the IMRT plan for NPC.%目的:通过比较常规调强计划与自动优化计划间的差异,探讨自动计划RapidPlan优化模块在鼻咽癌调强计划应用中的可行性.方法:选取60例经临床验证的优质鼻咽癌计划进行分析和特征提取,先建立一个特定的自动优化模型,然后用此模型对另外的15例鼻咽癌计划进行测试,比较这15例经模型测试优化后形成的自动计划与用常规调强优化的计划间的差异.采用SPSS 22.0版软件分别对两组计划的各主要参数行配对样本t检验分析.结果:自动优化产生的计划得到的剂量分布更佳;且自动优化比常规调强优化效率更高,自动计划的优化平均时间比常规调强计划缩短33.67％(P=0.001),优化次数也从平均3.5次降到2.2次(P=0.000);自动优化比常规调强优化的计划执行效率更高,MU值平均值减少376 MU,平均减少原来的14.8％(P=0.000).结论:基于解剖特性和先验知识的自动计划模块,即RapidPlan优化模块,通过建立优化模型,设置优化参数,产生的鼻咽癌调强计划,可以达到比常规调强计划更佳的靶区剂量分布结果,并且更好地降低正常组织的剂量,同时获得比常规调强计划更高的优化效率和计划执行效率,在鼻咽癌的调强计划优化中是切实可行的.