利用CT模拟机重建图像分析鼻咽癌摆位重复性  

Analyze Positioning Repeatability of Nasopharyngeal Carcinoma by Reconstruction Image Using CT Simulator

作　　者：陈健铃[1] 赵云辉[2] 陈传本[1] 李奇欣[1] 柏朋刚[1] 

机构地区：[1]福建省肿瘤医院放疗中心,福建福州350014 [2]莆田学院附属医院放疗科,福建莆田351100

出　　处：《中国医学物理学杂志》2012年第3期3346-3349,共4页Chinese Journal of Medical Physics

基　　金：福建省科技厅自然科学基金项目(No.2010J01137)

摘　　要：目的:探讨我院鼻咽癌放疗病人的体位重复性及摆位误差,制定更为可靠的体位固定方式,为鼻咽癌靶区勾画中的临床靶区(CTV)的外扩具体提供参考。方法:用CT模拟机对我院17例行放射治疗的鼻咽癌病人扫描CT,每周扫描一次,总共扫描6次。利用CT重建后的定位相(SURVEW)测量头部x轴方向(框上缘)与y轴方向的最大值,对6次数值进行统计学分析。比较相邻两次间摆位是否存在差异。结果:17例鼻咽癌患者分次间的摆位误差在x轴的分次摆位误差部分有统计学差异(第一次/第二次:t=2.446,P=0.026;第三次/第四次:t=2.584,P=0.02)y轴的分次摆位误差亦部分有统计学差异(第二次/第三次:t=-2.2,P=0.043)。x、y轴的误差范围分别为(-5.1 mm,5.3 mm)和(-2.95 mm,4.45 mm)。在y轴(头脚)方向误差相对x轴(左右)方向较小。结论:鼻咽癌放射治疗病人在分次摆位时有必要校正摆位误差;患者左右、头脚方向存在误差,头脚方向误差范围较小。本研究结果可作为临床放疗计划肿瘤靶区外扩边界的参考,为进一步完善计划靶区(PTV)扩边范围提供参考。Objective To investigate the positioning repeatability and set-up errors of the patients with positioning repeatability in order to provide reference data on the margin between the clinical target volume（CTV） and planning target volume（PTV）.Methods The 17 cases of hospital patients with nasopharyngeal carcinoma radiotherapy were scaned by CT simulator once a week,a total of 6 scans.Datas of 6 times were analysed using CT reconstruction phase（SURVEW） measuring head x-axis direction（on the edge of the box） and the y-axis direction of the maximum.To find whether adjacent positioning is different.ResultsTotally,17 cases of nasopharyngeal carcinoma among patients with fractionated x-axis positioning error in the positioning error of the sub-sub-part of a statistically significant difference（first / second：t = 2.446,P= 0.026;third / fourth time：t= 2.584,P= 0.02） y-axis positioning error is also graded part of a statistically significant difference（second / third time：t =-2.2,P= 0.043）.x,y-axis error in the range of（-5.1 mm,5.3 mm） and（-2.95 mm,4.45 mm）.In the y-axis（first leg） the relative error of the x-axis direction（left） direction of the smaller.Conclusions： Nasopharyngeal carcinoma patients in fractionated radiotherapy when necessary to correct positioning error anyway,the patient about the direction of the first leg there is error,direction error range smaller heads and feet.The results of this study can be used as clinical radiation treatment planning to expand outside the borders of the tumor volume reference,in order to further improve the planning target volume（PTV） while expanding the scope of reference.

关 键 词：鼻咽癌 调强放射治疗 摆位误差 CT扫描 

分 类 号：R739.63[医药卫生—肿瘤] R815.6[医药卫生—临床医学]