基于锥形束CT研究不同部位计划靶区外放边界  

Study on the external boundary of the planning target volume in different parts based on cone beam CT

作　　者：赵亮 马超[1] 闵骁 熊兵 吴炎 杨爱民 ZHAO Liang;MA Chao;MIN Xiao;XIONG Bing;WU Yan;YANG Aimin(Oncology Radiotherapy Department,Shaanxi Forest Industry Staff Hospital,Shaanxi Xi'an 710300,China;The First Affiliated Hospital of Xi'an Jiaotong University,Shaanxi Xi'an 710061,China)

机构地区：[1]陕西省森林工业职工医院肿瘤科放疗室,陕西西安710300 [2]西安交通大学第一附属医院,陕西西安710061

出　　处：《现代肿瘤医学》2024年第18期3549-3555,共7页Journal of Modern Oncology

摘　　要：目的:基于千伏级锥形束CT(cone beam CT,CBCT)图像引导技术,对放射治疗摆位误差进行修正,统计分析不同方向摆位误差值,并以此确定人体不同部位计划靶区外放边界。方法:选取头部、颈胸部、胸部和腹部肿瘤患者各30例,共120例。每例患者治疗期间选择第1、6、11、16、21、...次治疗,即每五次做一次治疗前的CBCT扫描、配准,获取摆位误差,计算PTV外放边界。结果:不同部位X轴、Y轴、Z轴三个方向的摆位误差(均值±标准差)为:头部X轴(1.06±0.08)、Y轴(1.45±1.06)、Z轴(0.87±0.62),颈胸部X轴(1.71±1.24)、Y轴(2.14±1.22)、Z轴(1.65±1.17),胸部X轴(1.62±1.19)、Y轴(1.56±1.15)、Z轴(1.43±1.00),腹部X轴(1.30±1.07)、Y轴(1.61±1.21)、Z轴(1.42±1.01)。肿瘤临床靶区(CTV)至计划靶区(PTV)的外放边界(Margin)在X轴、Y轴、Z轴方向上分别为:头部2.53 mm、2.96 mm、1.66 mm,颈胸部2.84 mm、2.71 mm、2.67 mm,胸部2.47 mm、2.38 mm、2.39 mm,腹部2.38 mm、2.40 mm、2.11 mm。结论:基于CBCT摆位误差得到的计划靶区外放边界在临床放射治疗中具有指导意义。Objective:Based on kV-level cone beam CT(CBCT)image guidance technology,the positioning errors of radiotherapy were corrected,and the positioning errors in different directions were statistically analyzed,so as to determine the external boundary of the planning target volume in different parts of the human body.Methods:A total of 120 patients with head,neck and chest,chest and abdomen tumors were selected.During the treatment period of each patient,the 1st,6th,11th,16th,21st,...for each treatment,CBCT scanning and registration were performed every five times before treatment,the positioning errors were obtained,and PTV external boundary was calculated.Results:The positioning errors(mean±standard deviation)in the three directions of X-axis,Y-axis and Z-axis in different parts were X-axis(1.06±0.08),Y-axis(1.45±1.06),Z-axis(0.87±0.62)for head,X-axis(1.71±1.24),Y-axis(2.14±1.22),Z-axis(1.65±1.17)for neck and chest,X-axis(1.62±1.19),Y-axis(1.56±1.15),Z-axis(1.43±1.00)for chest,and X-axis(1.30±1.07),Y-axis(1.61±1.21),Z-axis(1.42±1.01)for abdomen.The margin from the clinical target volume(CTV)to the planning target volume(PTV)in the X,Y and Z axes was 2.53 mm,2.96 mm and 1.66 mm for head,2.84 mm,2.71 mm,2.67 mm for neck and chest,2.47 mm,2.38 mm,2.39 mm for chest,2.38 mm,2.40 mm,2.11 mm for abdomen.Conclusion:The external boundary of the PTV based on the positioning error of CBCT is of guiding significance in clinical radiotherapy.

关 键 词：千伏级锥形束CT 摆位误差 图像配准 外放边界 

分 类 号：R730.55[医药卫生—肿瘤]