盆腔肿瘤精确放疗中自制辅助装置应用研究

Role of self-made auxiliary device in precise radiotherapy for pelvic tumor

目的 利用瓦里安机载CBCT研究自制辅助装置在体模固定盆腔肿瘤放疗中的作用。方法 选取盆腔肿瘤患者50例,按照入组顺序随机均分为对照组和研究组。研究组采用热塑体模和自制辅助装置加以固定,对照组用热塑体模固定。放疗前行CBCT扫描并在线匹配,得出左右﹑上下﹑前后方向摆位误差。组间比较行成组t检验。结果 研究组患者左右﹑上下﹑前后方向摆位误差分别为（1.56±1.00）﹑（1.60±1.29）﹑（1.36±1.00） mm,对照组的分别为（1.76±1.33）﹑（2.76±1.69）﹑（1.92±0.91） mm （P=0.551、0.009、0.043）。结论 自制辅助装置解决了体模固定在上下方向上误差,也可解决患者不自主的下肢活动的问题。

Objective To investigate the role of self-made auxiliary device in pelvic tumor radiotherapy with phantom immobilization using Varian cone-beam CT （CBCT）. Methods A total of 50 patients with pelvic tumor were enrolled and randomly divided into study group and control group according to the order of enrollment. The patients in the study group were immobilized with thermoplastic phantom and self-made auxiliary device, and those in the control group were immobilized with thermoplastic phantom. CBCT scan and online matching were regularly performed before radiotherapy to obtain the setup errors of the left-right （x）, cranial-caudal （y）, and anterior-posterior （z） directions. The independent-samples t-test was used for comparison between groups. Results The set-up errors in the x-, y-, and z-directions in the study group were 1.56±1.00 mm, 1.60±1.29 mm, and 1.36±1.00 mm, respectively, and those in the control group were 1.76±1.33 mm, 2.76±1.69 mm, and 1.92±0.91 mm, respectively （P=0.551, 0.009, and 0.043）. Conclusions Self-made auxiliary device helps to eliminate the errors in the cranial-caudal direction and solve the problem of involuntary activities of the lower limbs.