主动脉壁内血肿的MRI表现

MRI Appearance of Intramural Hematoma of Aorta

目的：探讨主动脉壁内血肿的MRI表现和特点。方法：对9例主动脉壁内血肿的MRI资料进行回顾性分析。其中Stanford A型4例，StanfordB型5例。全部病例均采用MRISE常规序列。结果：本组病例均示主动脉管腔正常或受压稍变小，约3．5～4．5cm；管壁均示增厚，横轴位2例管壁呈环形增厚、4例管壁呈新月形增厚；壁内血肿2例于T1WI呈等信号，T2WI呈较低信号，3例血肿T1WI及T2WI呈较均匀性高信号，1例于T1WI呈等信号，T2WI呈高信号；3倒壁分层，中间见等信号动脉中膜相隔，两侧信号不一致，T1WI血肿外侧部分呈等信号、内侧部分呈高信号，T2WI两侧均呈高信号。结论：主动脉壁内血肿的MRI表现具有一定特点，诊断价值大。

Objective：To investigate the MRI features of intramural hematoma of aorta. Methods：The MRI findings of 9 cases with aortic intramural hematoma were retrospectively analyzed,including Stanford type A （n= 6） and stanford type B （n=3）. Routine spin echo sequences were used. Results：The aortic lumen were shown as normal or slightly narrowed in all of the patlents,with the diameter measured 3.5 -4.5cm. The aortic wall were thickened, which were shown on axial plane as ring-like thickening （n= 2） or crescent shape thickening （n= 4）. In 2 cases, the signal intensity of intramural hematoma on TI WI were iso-intense,on T2 WI were hypo-intense ;in 3 cases, the signal intensity on T1WI as well as T2 WI were homogeneously hyper-intense;in 1 case, it was iso-intense on T1WI and hyper-intense on T2 WI. 3cases had aortic dissection, an iso-intense medium layer was showed, the signal intensities were different in the two sides of the medium layer, with iso-intense in the lateral part and hyper-intense in the medial part of hematoma on T1WI,and hyper-intense in both parts on T2 WI. Conclusion： MRI is very helpful in the diagnosis of intramural hematoma of aorta.