锥形束CT分析发泡胶个体化头枕在头颈部肿瘤调强放射治疗中的应用

摘要

目的:探讨发泡胶个体化头枕在头颈部肿瘤调强放射治疗体位固定中的应用价值.方法:选取92例头颈部肿瘤患者,共进行589次锥形束CT(CBCT)扫描,其中44例患者采用发泡胶个体化头枕体位固定(个体化组),进行了252次CBCT扫描,48例患者采用标准化头枕体位固定(标准组),进行了337次CBCT扫描.分析摆位误差,对误差结果进行分析并记录成小结供以后摆位时参考,记录两组患者的摆位误差结果并进行统计学分析.结果:个体化组在X、Y和Z轴的线性误差分别为(0.85士0.68) mm、(1.17±0.87) mm和(1.00±0.81) mm,旋转误差分别为(0.52±0.45)°、(0.72±0.49)°和(0.57±0.47)°;标准组在X、Y和Z轴的线性误差分别为(1.15±0.90) mm、(1.48±1.20) mm和(1.08±0.81) mm,旋转误差分别为(0.68±0.52)°、(0.77±0.55)°和(0.60±0.44)°;个体化组在X、Y轴的线性误差、X轴的旋转误差小于标准组,差异有统计学意义(P值分别为0.000、0.001、0.000).小结前标准组Y轴的线性误差大于小结后(P=0.001),个体化组小结前与小结后的线性误差和旋转误差差异均无统计学意义(P＞0.05).结论:相对于标准化头枕,个体化头枕可以减少X、Y轴的线性误差及X轴的旋转误差,个体化头枕体位固定稳定,摆位可重复性高,可在临床中推广应用.%Objective:To study the superiority of customized polyurethane foam filled support for patient immobilization in intensity-modulated radiotherapy for head and neck neoplasms.Methods:92 patients with head and neck neoplasms were selected,for whom a total of 589 CBCT scans were performed.44 patients were immobilized by customized polyurethane foam head and neck support,for whom 252 scans of CBCT were collected;48 patients were immobilized by standard support,for whom 337 images of CBCT were collected.Elekta's XⅥ software was used to analyze setup errors.For the first three times,CBCT testing was made every day and the error results were analyzed and summarized to offer reference for later positioning and,if the same direction linear error greater than 1mm,it was revised and the positioning center was remarked.Later,CBCT testing was made each week to collect the setup errors of two groups of patients and to make data analysis.Results:In the customized head and neck support group,the linear error on X-,Y-and Z-axis was (0.85 ±0.68)mm,(1.17 ± 0.87)mm and (1.00 ± 0.81)mm respectively;the rotation error on X-,Y-and Z-axis was (0.52 ±0.45)°,(0.72±0.49)° and (0.57±0.47)° respectively.In the standard head and neck support group,on X-,Y-and Z-axis,the linear error was (1.15±0.90) mm,(1.48 ± 1.20)mm and (1.08 ± 0.81)mm respectively,the rotation error was (0.68 ± 0.52)°,(0.60 ± 0.44) ° and (0.77 ± 0.55) ° respectively.In the customized head and neck support group,the linear error on X-and Y-axis,and ration error on X axis was smaller than that in the standard group,indicating statistical signifant difference (P ＜ 0.05).Before the summary,on Y-axis,the linear error of the standard pillow group was greater than the linear error after the summary,and for the customized pillow group,there was no difference before and after the summary.Conclusions:Compared with standard pillow,customized pillow can reduce the linear error on X-and Y-axis,and the rotation error on X-axis.The patient immobilization using customized pillow is stable.The repeatability of positioning is high,which makes the treatment more accurate and can be applied widely in clinical application.