获得性胸主动脉病变的MRI诊断

目的：评价ＭＲＩ对获得性胸主动脉病变的诊断价值。材料和方法：共３０例，２１例在ＧＥＶｅｃｔｒａ０．５Ｔ上行ＳＥ和ＣｉｎｅＭＲＩ检查，９例在ＧＥＳｉｇｎａ１．５Ｔ上行ＳＥ、ＣｉｎｅＭＲＩ、ＧａｔｅｄＴＯＦ和３Ｄ动态增强ＭＲＡ检查。成像采用横断面、主动脉长轴和左室长轴观，部分加扫矢状面和冠状面。结果：共发现升主动脉瘤１０例、主动脉夹层１０例、主动脉扩张９例和降主动脉溃疡１例。经对照表明ＣｉｎｅＭＲＩ对合并的瓣膜病变、夹层真假腔、血栓和瘤内异常血流方式的显示较ＳＥ为佳，而ＧａｔｅｄＴＯＦ和３Ｄ动态增强ＭＲＡ对整个胸主动脉形态及头臂血管的显示最佳。结论：多种ＭＲＩ技术综合运用诊断获得性胸主动脉病变可基本达到心血管造影效果。

MRI Diagnosis of the Acquired Thoracic Aortic Diseases

Purpose:To evaluate the value of MRI techniques in the diagnosis of acquired thoracic aortic diseases.Materials and Methods:30 cases were studied with MRI including 21 performed at a GE Vectra 0.5T system with both SE and Cine MRI and 9 performed at a GE Signa 1.5T system with SE,Cine MRI Gated TOF and 3D dynamic contrast MRA.Axial SE T1W images were acquired in all cases,SE T2W and Cine MRI images along the long axis of the aorta were undertaken in all cases.SE T1W and Cine MRI images along the long axis of the left ventricle were acquired in 27 cases.Sagittal or Coronal MRA images were acquired in 9 cases.Results:MRI clearly demonstrated the primary anatomic abnormalities with aneurysms of the ascending aorta in 10 cases,dilatation of the ascending aorta in 9 cases,aortic dissection in 10 cases and ulcer of the descending aorta in 1 case.By comparing the different MRI techniques,it was shown that Cine MRI was superior to SE in the demonstration of the associated valve anomalies, the distinction of the true and false lumen of the aortic dissection and the differentiation of the slow flow and thrombus as well as the depiction of the abnormal flow patterns in the ascending aortic aneurysms.Gated TOF and 3D dynamic contrast MRA were the best method for demonstrating the whole thoracic aorta and its main branches.Conclusion:The effect of the combination use of SE,Cine MRI and MRA in the evaluation of the acquired thoracic aortic diseases could approach to that of angiocardiography.