基于SGRT表面引导技术的自制开放式面罩在颅脑肿瘤放疗中的可行性研究

Feasibility Study of Self-Made Open Mask Based on SGRT Surface Guidance Technology in Radiotherapy of Craniocerebral Tumor

目的对传统封闭式面罩进行开窗改造,以满足AlignRT光学表面监测系统使用要求。方法回顾性选取中国科学技术大学附属第一医院合肥离子医学中心20例行颅内肿瘤放疗治疗患者,10例患者使用传统封闭式面罩固定(A组),10例患者使用自制开放式面罩固定(B组),所有患者分次治疗前进行锥形束CT扫描,配准移床后得到摆位误差值,比较2组摆位误差,同时通过Bland-Altman法进行一致性检验。结果B组在平移方向腹背(Vrt)、头脚(Lng)、左右(Lat)的摆位误差均显著低于A组(P<0.05);B组旋转方向俯仰角(Pitch)、翻滚角(Roll)、偏转角(Rtn)的摆位误差均低于A组,两组除Pitch方向差异不显著(P>0.05),其余各方向均差异显著(P<0.05);Bland-Altman一致性检验显示,大部分散点在Vrt、Lng、Lat、Pitch、Roll和Rtn方向上的95%置信区间内,说明2种面罩固定的摆位误差具有高度一致性,且临床应用中可接受该差异。结论自制开放式面罩在各个方向上的摆位误差均优于封闭式面罩,满足AlignRT光学表面监测系统使用要求,可明显提高摆位精准度和舒适度。

Objective To modify the traditional closed mask with open window to meet the requirements of using AlignRT optical surface monitoring system.Methods A total of 20 patients with intracranial tumors who had been treated with radiotherapy at the Hefei Ion Medical Center,The First Affiliated Hospital of University of Science and Technology of China were retrospectively selected.A total of 10 patients were fixed with a traditional closed mask(group A)and 10 patients were fixed with a homemade open mask(group B).CBCT scans were performed before all fractional treatments,and the positional error values were obtained after the alignment shift.The alignment errors of the two groups were compared,and the consistency test was carried out by Bland-Altman method.Results The positioning errors of group B in translational direction including Vrt,Lng and Lat were significantly lower than those of group A(P<0.05).The positioning errors in the rotation direction including Pitch,Roll and Rtn of group B were lower than those in group A.Except for the Pitch direction,which were no significant differences between the two groups(P>0.05),and the other directions were significantly different(P<0.05).Bland-Altman consistency test showed the 95%CI,of most scattered points in Vrt,Lng,Lat,Pitch,Roll and Rtn directions,indicating that the two mask fixed positioning errors were highly consistent,and the difference was acceptable in clinical application.Conclusion The self-made open face mask is better than the closed mask in all directions.It meets the requirements of the AlignRT optical surface monitoring system and significantly improves the positional accuracy and comfort.