多层螺旋CT在诊断结肠病变中的应用

目的；研究MSCT结肠检查4种后处理成像技术及其临床应用价值。方法：应用MSCT对37例患行一次屏气全结肠段容积扫描，包括结肠癌14例，结肠息肉16例，慢性结肠炎5例，结节型回盲辨误诊息肉1例，结肠多发憩室1例。除1例憩室外，均经手术和／或纤维结肠镜检查活检病理证实。在工作站获取多平面重建（MPR）、CT仿真结肠镜（CTVC）、三维表面遮盖显示（3D－SSD）、四维透明显示（4D－Raysum)4种后处理图像并进行比较。结果：CTVC有利于息肉的检出，本组显示最小息肉直径为3.5mm，与纤维内镜比较息肉的总检出率为86．5％。MPR能直观反映息肉和癌肿处理壁及肠周侵犯情况，对癌肿肠周侵犯判断正确率达100％，同时有助于结肠正常结构、粪块及肿瘤鉴别。4D－Raysum较3D－SSD、MPR及CTVC在显示癌肿长度上占优势，判断正确率可达100％，亦优于钡灌肠检查。结论：MPR、CTVC、3D－SSD、4D－Raysum检查结肠病变临床应用价值各有不同，4种后处理技术的结合更有利于结肠病变的诊断。

Application of multislice spiral CT in colorectal diseases

Objective:To evaluate the application of MSCT with four post processing techniques in colorectal diseases.Methods:The volumetric scanning of MSCT was performed in whole colorectum of 37 cases,then the data was transmitted to the workstation and multiplanar,reconstruction (MPR),CT virtual colonoscopy (CTVC),3D shaded surface display(3D SSD) and 4D Raysum were performed respectively.The cases included colonic carcinoma(n=14),colonic polyps(n=16),chronic colitis(n=5) and colonic diverticula(n=1).All cases were proved by the surgical findings or the fibercolonoscope biopsy except 1 case of colonic diverticula.Results:The detecting rate of CTVC in colonic polyps was 86.5%,and the smallest diameter was found 3.5mm in this group.MPR was helpful for displaying directly the polyps and the invasion of colonic wall and pericolic organ from colon carcinoma.The accuracy of detecting the invasion of pericolic tissue or organ was 100%.It was also helpful for distinguishing normal structure,feces and tumor lesion.In comparison with 3D SSD,MPR,CTVC and BE,4D Raysum was better in displaying the length of tumor,and its accuracy rate was 100%.Conclusion:MPR,CTVC,3D SSD,4D Raysum have their own advantages and values in the detection of colonic diseases.The combined use of the four post processing techniques is helpful for detecting and diagnosing colorectal diseases.