摘要
目的探讨基于锥形束CT(CBCT)评估体表标记线联合热塑膜固定法在宫颈癌容积旋转放射治疗中的应用价值。方法选择行容积旋转调强放射治疗的40例宫颈癌患者,年龄31~67岁,中位年龄49岁。按照固定方式不同将其随机分为研究组(n=22)和对照组(n=18)。研究组采用体表标记线联合热塑膜固定方式,对照组单纯采用热塑膜固定方式。所有患者首次放射治疗前行CBCT扫描及每周行1次CBCT扫描。将CBCT扫描得到的图像与计划系统传输图像进行灰度加旋转匹配获得的摆位误差进行分析,包括左右方向(X轴)、头脚方向(Y轴)、腹背方向(Z轴)的线性误差及分别以X、Y、Z为轴的俯仰(Rx)、侧翻(Ry)、偏转(Rz)的旋转误差。结果研究组和对照组在X轴、Y轴、Z轴方向的平移误差分别为(0.20±0.11)cm、(0.27±0.12)cm、(0.18±0.08)cm和(0.22±0.13)cm、(0.67±0.29)cm、(0.23±0.13)cm,在Rx、Ry、Rz方向的旋转误差为(0.47±0.38)°、(0.53±0.44)°、(0.61±0.34)°和(0.57±0.44)°、(0.68±0.39)°、(0.98±0.41)°。两组患者在Y轴、Rz方向的摆位精度相比,差异均有统计学意义(P<0.05)。结论在宫颈癌容积旋转放射治疗摆位中,通过体表标记线联合热塑膜的固定方式可以有效降低患者头脚方向的线性误差和旋转误差,且操作简单易行,临床上值得应用。
Objective To detect the value of surface marker combined with thermoplastic film fixation based on cone beam computed tomography(CBCT)in volumetric rotary radiotherapy for cervical cancer.Methods A total of 40 patients with cervical cancer underwent volumetric rotation-intensity modulated radiotherapy were enrolled,which aged 31-67 years old,with median age of 49 years old.According to different fixation methods,all of them were randomly divided into study group(n=22,performed body surface marking line combined with thermoplastic film fixation)and control group(n=18,performed thermoplastic film fixation).All patients underwent CBCT scan before the first radiotherapy and CBCT scan once a week.The set-up error obtained by CBCT scanning image and image transmitted by planning system for grayscale plus rotation matching were analyzed,including translational errors in left-right direction(X-axis),the superior-inferior direction(Y-axis),anterior-posterior direction(Z-axis),and rotation errors of X(Rx),Y(Ry)and Z(Rz).Results The translation error in X-axis,Y-axis,and Z-axis of study group and control group were(0.20±0.11)cm,(0.27±0.12)cm,(0.18±0.08)cm,and(0.22±0.13)cm,(0.67±0.29)cm,(0.23±0.13)cm,respectively;rotation error in Rx,Ry and Rz was(0.47±0.38)°,(0.53±0.44)°,(0.61±0.34)°and(0.57±0.44)°,(0.68±0.39)°,(0.98±0.41)°,respectively.There were statistically significant differences in positioning accuracy of Y-axis and Rz between 2 groups(P<0.05).Conclusion It is demonstrated that the fixation method of body surface marking line combined with thermoplastic film could effectively reduce translation error and rotation error at top-bottom direction in positioning of cervical cancer volume rotation radiotherapy which is simple and worthy of clinical application.
作者
冯进进
储开岳
王君辉
赵志刚
FENG Jin-jin;CHU Kai-yue;WANG Jun-hui;ZHAO Zhi-gang(Department of Radiotherapy,Nantong Tumor Hospital,Nantong University Affiliated Tumor Hospital,Nantong 226361,Jiangsu,China)
出处
《生物医学工程与临床》
CAS
2021年第6期738-742,共5页
Biomedical Engineering and Clinical Medicine
基金
南通市指导性计划项目(GJZ17043)。
关键词
宫颈癌
容积旋转调强
线性误差
旋转误差
cervical cancer
volume rotation intensity modulation
linear error
rotation error
