摘要
目的:探讨无创颅脑立体定向放射外科(stereotactic radiotherapy surgery,SRS)中ExacTrac X射线图像引导系统纠正摆位误差的精确性。方法:选择30例颅脑肿瘤患者,在SRS治疗前用ExacTrac X射线图像引导系统验证,利用六维床校正Lat(左右)、Long(头脚)、Vert(前后)3个平移误差和Lat Ang、Long Ang、Vert Ang 3个旋转误差,并在校正后的位置上再拍一组X射线片与数字重建放射影像(digitally reconstructured radiograph,DRR)匹配,记录6个方向的误差值,分析校正前后6个方向的均值和标准差。匹配完成后进行锥形束CT(cone beam CT,CBCT)扫描,医生在线匹配CBCT图像与定位CT图像,得到Lat、Long、Vert 3个平移误差,将其与经ExacTrac X射线图像引导系统校正后的3个平移误差进行比较,分析2个系统的设置差异。结果:校正前Lat、Long、Vert 3个平移误差平均值/标准差分别为-0.42/1.15 mm、0.72/1.29 mm、-0.49/1.13 mm,Lat Ang、Long Ang、Vert Ang 3个旋转误差均值/标准差分别为-0.34/0.83°、-0.11/1.01°、0.30/1.33°。校正后6个方向的误差明显缩小,3个平移方向的误差均≤0.5 mm,3个旋转方向的误差均<0.5°。3个平移方向和Lat Ang旋转方向误差差异具有统计学意义(P<0.05),在Long Ang、Vert Ang 2个旋转方向误差差异不具有统计学意义(P>0.05)。CBCT与ExacTracX射线图像引导系统2个系统3个平移方向误差的差值均≤2 mm。结论:应用ExacTrac X射线图像引导系统配合六维床可明显减小误差值,说明在颅脑SRS治疗中应用ExacTrac X射线图像引导系统是很有必要的。
Objective To investigate the accuracy of ExacTrac X-ray image guidance system and compare the setup errors with ExacTrac X-ray image guidance system and cone-beam computed tomography(CBCT) for intracranial non-invasive stereotactic radio-therapy surgery(SRS). Methods Totally 30 craniocerebral tumor patients underwent pre-SRS verification by ExacTrac X-ray image guidance system, and the 6 D bed was used to correct the translation and rotation errors at the directions of Lat(left-right), Long(head-feet) and Vert(forward-backward) as well as Lat Ang, Long Ang and Vert Ang. Then another group of X-ray images were taken at the corrected position and matched with DRR images, and the values were recorded at the six directions. The mean values and standard deviations were analyzed before and after correction. After the matching was completed cone beam CT(CBCT) scan was performed. The doctor matched the CBCT image and the CT image online, and obtained the translation errors at Lat, Long and Vert. The translation errors obtained were compared with those undergoing correction by Exactrac X-ray image guidance system to analyze the setup difference between the two systems.Results Before correction the mean errors and standard deviations were respectively-0.42/1.15 mm, 0.72/1.29 mm and-0.49/1.13 mm at Lat, Long and Vert directions, and-0.34/0.83°,-0.11/1.01° and 0.30/1.33° respectively at Lat Ang, Long Ang and Vert Ang directions. After correction the errors decreased significantly at the six directions, which were not more than 0.5 mm at the translation directions and less than 0.5° at the rotation directions. There were statistical differences for the errors at the three translation directions and Lat Ang directions(P<0.05), while no for those at Long Ang and Vert Ang directions(P>0.05). The two systems had all the differences between the errors at the three translation directions not more than 2 mm.Conclusion ExacTrac X-ray image guidance system combined with 6 D bed decreases the error significantly, and thus gains nec
作者
谭薇薇
罗灿
周军
TAN Wei-wei;LUO Can;ZHOU Jun(The Second Affiliated Hospital of Army Medical University,Chongqing 400037,China)
出处
《医疗卫生装备》
CAS
2019年第7期44-48,共5页
Chinese Medical Equipment Journal
