摘要
目的探讨MR引导的Unity放疗系统在临床应用中的可行性。方法临床试验入选24例患者,按治疗部位分为头颈组、胸腹组、盆腔组、脊柱组和肢体组,总共384个治疗分次。在无外置激光的情况下进行摆位,统计在线治疗流程中不同阶段所需时间和每个分次的配准误差。每周利用MR几何形变模体检测MR图像几何形变大小。并利用ArcCheck对参考计划、在线计划及离线计划进行剂量验证。结果头颈组、胸腹组、盆腔组、肢体组、脊柱组平均治疗时间分别为29.1、27.6、26.6、25.6、32.0min。5个组左右、上下、前后方向平均摆位误差分别为头颈组(0.08±0.06)、(0.16±0.13)、(0.08±0.05)cm,胸腹组(0.23±0.18)、(0.50±0.47)、(0.12±0.1)cm,盆腔组(0.25±0.19)、(0.32±0.25)、(0.11±0.09)cm,肢体组(0.46±0.38)、(0.26±0.26)、(0.13±0.07)cm,脊柱组(0.33±0.30)、(0.34±0.23)、(0.08±0.06)cm。在中心区域MR几何形变大小在0.3mm以内,直径500mm的球体区域内形变大小在2.1mm内。所有参考计划、在线计划、离线计划平均γ通过率分别为97.92%、97.84%、94.58%。结论MR引导放疗具有较大临床应用潜力,但MR引导的Unity放疗系统流程较为复杂,各部门的协同性对治疗的影响较大,还需进一步优化。
Objective To investigate the clinical feasibility of the Unity radiotherapy system guided by magnetic resonance imaging.Methods Twenty-four patients were enrolled and received a total of 384 fractions of treatment at Unity system.According to the treatment site,all patients were divided into head-neck,abdomen-thorax,pelvic,spine and limb groups.The patients were set-up without external laser.And then,the time required at different stages in online treatment process and the registration error of each fraction were separately calculated.The geometric deformations of MR images were weekly measured by using MR geometric deformation phantom.At last,the Arccheck was used to perform the dose verification of reference plan,online plan and offline plan.Results The mean duration of radiotherapy in the five groups were 29.1,27.6,26.6,25.6 and 32.0min,respectively.The set-up errors in the left-right,superior-inferior and anterior-posterior direction in the five groups were:head-neck group(0.08±0.06cm,0.16±0.13cm,0.08±0.05cm),abdomen-thorax group(0.23±0.18cm,0.50±0.47cm,0.12±0.1cm),pelvic group(0.25±0.19cm,0.32±0.25cm,0.11±0.09cm),spine group(0.46±0.38cm,0.26±0.26cm,0.13±0.07cm)and limb group(0.33±0.30cm,0.34±0.23cm,0.08±0.06cm),respectively.In the central region,the geometric deformation of MR was less than 0.3mm,and that of the sphere with a diameter of 500mm was less than 2.1mm.The meanγpass rate of the reference plan,online plan and offline plan were 97.92%,97.84%and 94.58%,respectively.Conclusions MR-guided radiotherapy has great potential for clinical application,whereas the process of Unity system is relatively complex.The synergy of different departments has a great impact on the treatment,which needs further optimization.
作者
刘镖水
郭旋
丁寿亮
王彬
李永宝
夏云飞
欧阳翼
黄晓延
林承光
Liu Biaoshui;Guo Xuan;Ding Shouliang;Wang Bin;Li Yongbao;Xia Yunfei;Ouyang Yi;Huang Xiaoyan;Lin Chengguang(State Key Laboratory of Oncology in South China,Collaborative Innovation Center for Cancer Medicine,Department of Radiation Oncology,Sun Yat-sen University Cancer Center,Guangzhou 510060,China)
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2021年第2期134-139,共6页
Chinese Journal of Radiation Oncology
基金
广东省自然科学基金(2018A0303100020)。
关键词
摆位误差
恶性肿瘤/MR引导放射疗法
Unity加速器
Set-up error
Malignant tumor neoplasm/magnetic resonance-guided radiotherapy
Unity accelerator
