多层螺旋CT后处理技术诊断主动脉夹层

目的探讨64层螺旋CT后处理技术诊断主动脉夹层的价值。方法 87例主动脉夹层患者均接受64层螺旋CT血管造影,在工作站用动脉期薄层图像进行图像后处理,比较3D成像中VRT自由切割成像及仿真内镜（VE）与其他后处理方法对腹腔干以上水平内膜破口的显示率。结果 87例中,De BakeyⅠ型19例,Ⅱ型5例,Ⅲ型63例。各种重建方法对内膜破口的显示率由高到低依次为VRT自由切割成像（81/87,93.10%）、MPR（80/87,91.95%）、CPR（79/87,90.80%）、轴位＋VE（79/87,90.80%）、轴位（78/87,89.66%）、VR（41/87,47.13%）、MIP（22/87,25.29%）,差异有统计学意义（χ2=106.376,P〈0.001）。结论 CTVE能立体直观地显示破口位置,结合轴位图像可提高对破口的显示率;VRT自由切割成像对破口显示率较VR明显提高,优于MPR。

Post-processing techniques of MSCT in diagnosis of aortic dissection

Objective To investigate the value of post-processing techniques in 64-slice spiral CT in diagnosis of aortic dissection.Methods Totally 87 patients with aortic dissection underwent 64-slice spiral CT angiography.In the arterial phase,thin-layer images were post-processed with workstation,and the display rate in 3D free cut VRT imaging,CT virtual endoscopy（VE） and other post-processing methods on intimal tear above the level of celiac were compared.Results De Bakey Ⅰ type was found in 19,Ⅱ in 5 and Ⅲ in 63 patients.Display rate of the intimal tear of VRT free cut was 93.10%（81/87）,of MPR was 91.95%（80/87）,of CPR was 90.80%（79/87）,of axial view combined with VE was 90.80%（79/87）,of axial view was 89.66%（78/87）,of VR was 47.13%（41/87） and of MIP was 25.29%（22/87）,from high to low（χ2=106.376,P0.001）.Conclusion CTVE combined with axial images can improve the display rate of the break in aortic dissection.Compared with VR and MPR,VRT free rate cut can increase the display rate of the break significantly.