基于仰卧位全脑全脊髓无缝整体调强技术可行性研究  

Feasibility of integrated IMRT technique for craniospinal irradiation in a supine position

作　　者：蔡晓君[1] 郭建[2] 周菊英[2] 蒋华[2] 张汝婷[2] 徐文涛[2] 徐晓婷[2] 秦颂兵[2] Cai Xiaojun;Guo Jian;Zhou Juying;Jiang Hua;Zhang Ruting;Xu Wentao;Xu Xiaoting;Qin Songbing(Department of Radiation Oncology,Suzhou Kowloon Hospital,Suzhou 215000,China;Department of Radiation Oncology,First Affiliated Hospital of Soochow University,Suzhou 215008,China)

机构地区：[1]上海交通大学医学院附属苏州九龙医院,苏州215000 [2]苏州大学附属第一医院放疗科,苏州215008

出　　处：《中华放射肿瘤学杂志》2018年第12期1078-1082,共5页Chinese Journal of Radiation Oncology

摘　　要：目的 探讨基于仰卧位情况下开展全脑全脊髓无缝整体调强技术的可行性和安全性.方法 患者在仰卧位下使用头部面膜加体部真空垫固定组合,根据患者身高使用固定间距( 20~25 cm)的3个中心坐标. 3个中心计划共13个野,在衔接部射野重叠2~3 cm左右,采用固定钨门,逆向优化的方式进行整体计算.对3个等中心和两个射野重叠处靶区分别进行平面剂量通过率及绝对点剂量验证分析.治疗前对3个中心一次性摆位后进行3个中心CBCT扫描,分别得出3个中心在同一坐标系中左右、头脚、前后方向上的误差,并作整体分析.结果 28例患者颈、胸、腹射野等中心点、颈胸射野衔接点、胸腹射野衔接点的平面剂量γ百分通过率和点剂量百分剂量偏差平均分别为99. 36%、99. 60%、99. 75%、94. 77%、95. 09%和1. 56%、-1. 56%、0. 52%、-0. 76%、-1. 68%. 28例患者共进行162组图像引导放疗,获得486次各中心CBCT图像的摆位偏差,其中颈、胸、腹各中心左右,头脚,前后方向的平均偏差分别为0. 17、0. 10、0. 02 mm,0. 06、0. 04、0. 46 mm,0. 19、0. 26、0. 41 mm.结论 基于仰卧位全脑全脊髓无缝整体调强技术安全可行,值得临床推广.Objective To explore the feasibility and safety of integrated intensity-modulated radiation therapy (IMRT) technology applied in craniospinal irradiation in a supine position. Methods The patients were fixed in a supine position using thermoplastic mask and vacuum mat. Three isocenters with a fixed interval of 20-25 cm were adopted according to the height of patients. A total of 13 beams with a length of 2-3 cm in the overlapping region were included in the treatment plan. Fixed jaw technique was employed and overall calculation was performed by the inverse optimization method. The γ-passing rate and absolute point dose verification were performed for three isocenters and two overlapping regions. Cone-beam CT (CBCT) images were scanned for three isocenters before treatment. The setup error of each isocenter in the x,y and z directions of the same coordinate system was recorded and overall analysis was conducted. Results Among 28 patients,the γ-passing rate (%) of three isocenters and two overlapping regions was 99. 36%, 99. 60%,99. 75%,94. 77% and 95. 09%,whereas the absolute point dose verification error was 1. 56%,-1. 56%,0. 52%,-0. 76% and -1. 68%,respectively. Twenty-eight patients received 162 groups of IGRT with 486 setup errors from the CBCT images. The average deviation in the x, y and z direction for three isocenters (neck,chest and abdomen) was 0. 17 mm,0. 10 mm,0. 02 mm,0. 06 mm,0. 04 mm,0. 46 mm, 0. 19 mm, 0. 26 mm and 0. 41 mm, respectively. Conclusions The integrated IMRT techniques for craniospinal irradiation in a supine position is feasible and safe,which is worthy of clinical application.

关 键 词：全脑全脊髓照射 剂量衔接 摆位误差 剂量验证 

分 类 号：R730.55[医药卫生—肿瘤]