锥形束CT引导下宫颈癌患者个体因素与摆位误差的相关性分析  

Correlation analysis between individual factors and set-up errors under guidance with CBCT in patients with cervical cancer

作　　者：王笑 付秀根 郑祖安 钟伟伟 孙海峰 刘凯 WANG Xiao;FU Xiu-gen;ZHENG Zu-an(Department of Oncology,Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology,Wuhan 430030,China;不详)

机构地区：[1]华中科技大学同济医学院附属同济医院肿瘤科,湖北武汉430030

出　　处：《中国医学装备》2022年第2期49-52,共4页China Medical Equipment

摘　　要：目的:探讨锥形束CT(CBCT)引导下宫颈癌患者的个体因素及其变化与摆位误差之间的相关性。方法:选取在医院就诊且行放射治疗的23例宫颈癌患者,采用CT模拟定位时测量患者身高、体质量、腰围以及臀围与膀胱容量,并计算体质量指数(BMI);放射治疗前进行CBCT扫描获取容积图像与计划CT图像进行配准,并同步测量患者身高、体质量、腰围以及臀围与膀胱容量,每例患者进行6~9次CBCT验证,共计验证188次,计算每次治疗与定位时患者体质量、膀胱容量与腰臀围的变化量,记录左右(x轴)、头脚(y轴)和前后(z轴)3个轴向的线性误差,以及对应的旋转摆位误差(xr、yr和zr)。应用Pearson相关分析法分析患者个体因素与摆位误差之间的关系。结果:宫颈癌患者膀胱容量、BMI、体质量与摆位总误差具有相关性(r=0.285,r=0.236,r=0.156;P<0.05);患者个体因素的变化与旋转误差有相关性,体质量与腰臀围的变化影响y轴的旋转误差,腰臀围的变化影响z轴的旋转误差;体质量与臀围的变化影响z轴的线性误差;而个体膀胱容量的变化与摆位误差之间无相关性。头脚方向的水平线性误差显著大于其他方位,而对应的旋转误差显著高于前后方向的旋转误差。结论:CBCT引导宫颈癌患者放射治疗时,应考虑患者的身高、体质量、腰围和膀胱容量及其变化量等影响因素,需制定个性化的化临床靶区体积(CTV)至计划靶区体积(PTV)外扩边界,体位固定时应注意患者头脚方向的固定,以降低误差提高放射治疗精度。Objective:To explore the correlation between“individual factors and their changes”and set-up errors under the guidance with cone beam computed tomography(CBCT)in patients with cervical cancer.Methods:This study enrolled 23 patients with cervical cancer who underwent radiotherapy in hospital.The height,body mass,waist circumference,hip circumference and bladder volume were measured and body mass index(BMI)was calculated during simulated location of CT.CBCT scan was performed to obtain volume image,which was registered with planned CT images,before radiotherapy.And the height,body mass,waist circumference,hip circumference and bladder volume were measured at the same time.Each patient underwent CBCT validations(6-9 times)and the total number of validations was 188 times.The variable quantities of body mass,bladder volume and waist-hip circumference in each of the treatment and CT location were calculated,and the linear errors of left-right direction(x axis),head-foot direction(y axis)and front-back direction(z axis)and the corresponding rotational set-up errors(xr,yr,zr)were recorded.Pearson correlation analysis was used to analyze the relationship between individual factors and set-up errors.Results:Bladder volume,BMI and body mass were correlated with general set-up error in patients with cervical cancer(r=0.285,r=0.236,r=0.156,P<0.05).The changes of individual factors of patients were related to the rotation error.The changes of body mass and waist-hip circumference affected the rotation error of y axis,and the change of waist-hip circumference affected the rotation error of z axis.In addition,the changes of body mass and hip circumference affected the linear error of z axis.But there no correlation was found between the change of individual bladder volume and set-up error.The linear error at head-foot direction was significantly larger than that that at other directions,and the corresponding rotational errors at head-foot direction was significantly higher than that at front-back directions.Conclusion:The i

关 键 词：锥形束CT(CBCT) 宫颈癌 摆位误差 个体因素 

分 类 号：R814.42[医药卫生—影像医学与核医学]