螺旋CT不同成像方法在主动脉夹层诊断中的比较

目的 评估螺旋CT不同成像方法在主动脉夹层诊断中的意义。资料与方法 对29例主动脉夹层患者的2D、MPR以及包括MIP、SSD和3DMT的三维成像进行对比。其中10例与手术所见对照。结果 2D、MPR和3DMT成像对内膜瓣的显示率为93.1％(27／29)，MIP、SSD和3DMT成像均不能显示血管腔内膜瓣轮廓；2D成像对破口的显示率为65．5％(19／29)，与手术符合率为100％(10／10)，MPR成像的显示率为13．8％(4／29)，MIP、SSD和3DMT未能显示破口；2D、MPR和3DMT成像对真、假腔的显示率为93．1％(27／29)，区分率均为92．6％(25／27)；SSD对两腔显示率为68.9％(20／29)，不能区分真假腔，有2例仅显示了一个腔；2D、MPR和3DMT对血栓的显示率均为51.7％(15／29)，SSD为13．8％(4／29)；2D成像100％(29／29)能判断其起始与终止部位。MPR能部分分段显示，SSD和3DMT均能整体显示；夹层邻近的血管分支的受累，2D图像显示率为71.4％(20／28)，其余重建方法难以显示。结论 螺旋CT对主动脉夹层的成像能采用多种重建方法，提供具有各自特点的图像信息，满足临床的要求。

Evaluation of Different Spiral CT Reconstruction Techniques in Diagnosing Aortic Dissection

Objective To evaluate two-dimensional (2D) axial , multi-planar reconstruction (MPR), maximum intensity project (MIP), shaded surface display (SSD), three-dimensional multi-tissue (3DMT) reformation in diagnosing aortic dissection.Materials and Methods Spiral CT scanning was performed in 29 patients with aortic dissection. Images of 2D, MPR, MIP, SSD and 3DMT obtained from source data were compared with each other. The imaging findings were compared with surgical results in 10 cases.Results The detecting rate of intimal flap, double lumen and athrosclerotic changes on 2D, MPR or 3DMT images was 93.1% (27/29). The demonstration of lacerated inlet was 65.6% (19/29) on 2D and 13.8% (4/29) on MPR images. MIP, SSD and 3DMT could not show the entry site in all cases. The displaying rate of double lumen on SSD alone was 68.9% (20/29), but differentiation of the true lumen from the false one could not be made in all cases. The demonstration of thrombosis was 51.7% (15/29) on 2D, MPR or 3DMT and 13.8% (4/29) on SSD. Both the beginning and the end of the aortic dissection could be judged on 2D in all cases (29/29). The involvement of the branches adjacent to the dissection was 71.4% (20/28) on 2D, which was hardly displayed on the other reconstructions.Conclusion Spiral CT scanning has the advantage to display aortic dissection with multiple imaging reconstructions, providing clinicians with more useful information concerning aortic dissection.