鼻咽癌IMRT与VMAT治疗的计划与剂量验证比较研究  

Comparative Study on the Planning and Dosimetric Verification of IMRT and VMAT in the Treatment of Nasopharyngeal arcinoma

作　　者：易金玲[1] 金献测[1] 周永强[1] 阎华伟[1] 韩策[1] 吴志勤[1] 黄珂靖[1] 谢聪颖[1] 

机构地区：[1]温州医学院附属第一医院放化疗科,浙江温州325000

出　　处：《中国医学物理学杂志》2013年第1期3859-3865,共7页Chinese Journal of Medical Physics

摘　　要：目的:比较研究IMRT与VMAT技术在鼻咽癌治疗中的计划与剂量验证。方法:对8位鼻咽癌患者,分别设计了7野IMRT计划,单弧与双弧VMAT计划,比较分析各计划参数,并对各计划进行治疗前的剂量验证。结果:鼻咽癌的IM-RT,单弧与双弧VMAT计划的靶区覆盖率分别为百分之99.00±0.79,89.92±6.32和97.98±1.29;γ分析相对剂量通过率分别为百分之91.91±4.64,97.65±1.45和97.36±2.25。IMRT,单弧与双弧VMAT计划的优化时间分别为:4.74±1.06,20.8±4.83和40.36±12.55分钟;所需要的出束时间分别为:11.01±0.43,1.75±0.07和4.01±0.28分钟;所需的MU平均值分别为1020.88±106.95,425.88±25.34和566.38±54.38。结论:对于鼻咽癌病人,单弧VMAT计划的靶区覆盖率不够,双弧VMAT计划可获得与IMRT相似的靶区覆盖率,同时减少所需的MU与出束时间。现有加速器与计划系统能够准确地计算和执行VMAT计划。Objectives： to comparative study the planning and pretreatment quality assurance between intensity modulated radio- therapy （IMRT） and volumetric modulated arc therapy （VMAT） in the treatment of nasopharyngeal carcinoma （NPC）.Methods： Eight patients of nasopharyngeal carcinoma with various stages were enrolled in this study. Seven field step-and-shot IMRT, one-arc and two-arc VMAT plans with identical objective functions were generated for these patients. Target coverage （TC） and dosimetric verification with ArcCheck phantom were analyzed. Results： the percentage TC of IMRT, one-arc and two-arc VMAT were 99.00±0.79, 89.92±6.32 and 97.98± 1.29, respectively. The pass ratio of relative ± analysis was 91.91±4.64,97.65± 1.45, and 97.36±2.25, respectively for IMRT, one-arc and two-arc VMAT plans. The optimization time was 4.74±1.06, 20.8± 4.83 and 40.36±12.55 minutes, respectively; the delivery time was 11.01±0.43, 1.75±0.07, and 4.01±0.28, respectively; the MU required was 1020.88＋ 106.95,425.88＋25.34, and 566.38＋54.38, respectively. Conclusion： the TC of one-arc VMAT was not e- nough in NPC. The TC of two-arc VMAT was close to that of IMRT with a reduced delivery time and MU. The increased free- dom of VMAT does not affect its delivery accuracy. The modem treatment planning system and linear accelerator are able to plan and delivery the VMAT plans accurately.

关 键 词：鼻咽癌 调强放射治疗 容积调强弧形放射治疗 剂量验证 

分 类 号：R73[医药卫生—肿瘤]