64层螺旋CT血管成像在主动脉夹层诊断中的临床价值

摘要

目的:探讨64层螺旋CT血管成像(CTA)在主动脉夹层(AD)诊断及术前评价中的应用价值.方法:58例连续性AD患者行64层螺旋CTA,对所有数据进行MPR、MIP、VR等重建分析.结果:CTA结果显示依据DeBakey分类法,Ⅰ型夹层14例,Ⅱ型2例,Ⅲ型42例.所有患者均存在明确的撕裂内膜片及真假腔,动脉期真腔平均CT值较假腔高,差异有统计学意义(P=0.000＜0.05).所有患者均明确显示了初始破口的位置,55例显示了一个或多个再破口,3例Ⅲ型患者未显示再破口.39例Ⅲ型患者初始破口位于主动脉弓降部或降胸主动脉近端,其近端瘤颈长度、宽度分别为0.4～10.8 cm(平均3.5 cm)、2.2～3.6 cm(平均2.8 cm),瘤体最大径为3.2～9.2 cm(平均5.4 cm).图像准确显示了所有患者主动脉重要分支受累以及假腔内血栓形成情况.结论:64层螺旋CT血管成像具有无创、快速、准确性高等优点,是主动脉夹层诊断及术前评价的可靠影像学检查方法之一.%Objective: To investigate the clinical value of multi-slice spiral CT angiography (MSCTA) in the diagnosis and preoperative assessment of aortic dissection (AD). Methods: Fifty-eighty consecutive patients with AD underwent 64-slice spiral CT angiography. The original data were post-processed with MPR,MIP and VR techniques and the results were analyzed. Results: Based on Debakey classification, the MSCTA results of these fifty-eight patients were classified as Type I ( 14 patients) ,Type Ⅱ (2 patients) and Type Ⅲ (42 patients). True and false lumen and intimal flap tearing could be clearly revealed in all of these 58 patients. Furthermore,the mean CT value after enhancement in true lumen is higher than that in false lumen in arterial phase, with significant statistical difference (F=0. 000<0. 05). Initial entry sites were well defined in all patients, and one or multiple re-entry sites were shown in 55 patients .but did not showed in 3 patients with Type HI dissection. In 39 patients with Type Ⅲ dissection, the initial entry site located in descendent part of aortic arch or proximal part of thoracic aorta, the length and the width of proximal neck of aortic aneurysm were ranged from 0. 4cm to 10. 8cm (mean, 3. 5cm) and ranged from 2. 2cm to 3. 6cm (mean,2. 8cm) respectively,and the maximum diameter of aortic aneurysm was between 3. 2cm and 9. 2cm (mean 5. 4cm). All of the main branches of aorta involved by dissection and the thrombus within false lumen were accurately showed by MSCTA Conclusion:The advantages of 64-slice spiral CT angiography are fast,non-invasive and highly effective which is one of the reliable imaging methods in the diagnosis and preoperative evaluation of aortic dissection.