MSCT扫描方式对图像后处理质量影响的研究  

Effect of MSCT scanning methods on image post-processing quality

作　　者：兰永树[1] 郭永萍[1] 兰永会[1] 肖正远[1] 

机构地区：[1]泸州医学院附属医院CT室,四川泸州646000

出　　处：《医学影像学杂志》2011年第8期1265-1268,共4页Journal of Medical Imaging

摘　　要：目的:探讨MSCT扫描方式对图像后处理质量的影响。方法:对我院2009年8月～2010年8月间因头面部外伤致骨折需要作CT三维重建的伤者200例,其中男性108例、女性92例,年龄29～65岁,随机平分为2组,采用GE64层螺旋CT以相同的扫描参数及扫描范围,分别对两组病例进行轴向、螺旋扫描,扫描图像传至AW4.3工作站进行图像后处理。辐射剂量在扫描后机器自动记录的信息中获得CT剂量指数(CTDIvol)、剂量长度乘积(DLP)等信息,并直接比较两种扫描方式辐射剂量的大小。图像质量由三名有丰富经验的主管、副主任技师对原始图像、VR及MPR图像进行颅脑组织结构及骨折线清晰度的大小、伪影的有无及大小、有无扫描间隔线等方面进行评价。结果:轴向扫描较螺旋扫描的CTDIvol及DLP更低。轴向扫描原始图像上颅脑及周围结构清晰度较螺旋扫描大,并且均无明显伪影,而螺旋扫描有明显伪影。轴向扫描VR图像均有扫描间隔线,但并不影响对骨折的观察,而螺旋扫描没有;轴向扫描VR图像上对颅骨骨折线的观察与螺旋扫描之间没有明显差别;轴向扫描所有VR图像上没有伪影,而螺旋扫描却有。轴向扫描MPR图像上均有扫描间隔线,也不影响对骨折及其他结构的观察,而螺旋扫描没有;轴向扫描MPR图像上没有明显伪影,而螺旋扫描却有并影响对脑组织及其周围结构的观察。结论:在扫描参数相同的条件下,MSCT轴向扫描的辐射剂量更低而图像后处理质量更高。Objective：To discuss the effect of MSCT scanning methods for the processing of image quality. Methods：200 cases from August 2009 to August 2010 in our hospital due to head and face traumatic fracture needed CT three-dimensional reconstruction, which consited of 108 males and 92 females, aged 29 to 65 years old, were randomly equally divided into 2 groups. The two groups were respectively scaned with axial scanning and helical scanning by GE 64-slice spiral CT, with the same parameters and scanning range. The image was transmitted to AW4.3 image post-processing workstation. Radiation dose parameters, such as CT dose index （CTDIvol）, dose length product （DLP）, the efficiency of X-ray were obtained from the automatic recorded information after scanning, and be directly recorded about the difference. The quality of the image were evaluated by three experienced executives, deputy director of the technicians through the original image, VR and MPR image to the skull organizational structure to clarify the fracture line, falseshade, scan line spacing. Results： The axial scanning has lower radiationg dose than spiral scanning. The definition of original image of skull and surrounding structures in axial scanning is higher than helical scanning, and no obvious false shade, but opposite in helical scan. The interval line lies in all of VR and MPR image of axial scanning, but does not affect the observation of fractures, and not in spiral scanning; There is no significant difference between the spiral scanning and axial scanning about observation on the skull fracture; all VR image of axial scanning have no artifacts, while, the spiral scan have this friar. Axial MPR images are scanned and line scan interval does not affect the structure of the fractures and other observations. There is no obvious artifacts on MPR images of axial scanning, but it hinders observation on the brain and the surrounding structures. Conelusion：With the same scanning conditions, MSCT axial scanning has lower radiation dose and highe

关 键 词：图像后处理 辐射剂量 图像质量 体层摄影术 X线计算机 

分 类 号：R811[医药卫生—放射医学] R814.42[医药卫生—临床医学]