血管内超声显像在判别主动脉夹层内脏动脉供血中的作用

The application of intravascular ultrasound imaging in identifying the visceral artery in aortic dissection

目的 评价血管内超声 (IVUS)显像在判别主动脉夹层内脏动脉供血中的作用。方法 对 2 2例主动脉夹层患者于数字减影动脉造影 (DSA)后经股动脉导入超声探头行IVUS检查。观察真假腔的超声结构 ,判别夹层范围内内脏动脉与真假腔的关系 ,将IVUS对内脏动脉的检出率与CT和DSA作对照。根据IVUS显像中夹层内膜片与内脏动脉开口的关系判别内脏动脉有无缺血以及缺血的原因 ,并与常规诊断方法相比较。结果 通过IVUS可发现真腔外侧壁显示三层超声结构 ,而假腔外侧壁仅显示一层超声结构 ,假腔外侧壁和内膜片相接处形成一个特征性的锐角 ,假腔内可发现有血栓 ,根据这些表现可对真假腔进行鉴别。 84支内脏动脉中 ,IVUS可判别 81支与真假腔的关系 ,5 4支开口于真腔 ,2 7支开口于假腔 ,检出率为 96 .4 % ,高于CT( 70 .2 % )和DSA( 84 .5 % ) ,差异有显著意义( χ2 =2 0 74和 6 .91,P <0 .0 1)。IVUS发现 6支内脏动脉开口受夹层累及导致狭窄 ,另有 1支因真腔明显受压 ,其开口被夹层内膜片覆盖。常规CT检查方法仅发现 2支内脏动脉开口受累。结论 IVUS可发现主动脉夹层内脏动脉的静态狭窄和动态狭窄 。

Objective To study the role of intravascular ultrasound (IVUS) imaging in identifying the visceral artery in aortic dissection. Methods Twenty two patients with aortic dissection were studied by IVUS via a femoral approach. The relationship between the visceral artery origin and the true and false lumens were differentiated by IVUS. The detection rate of visceral artery by IVUS was compared with those of CT and digital subtraction angiography (DSA).The cause of visceral ischemia was determined by the relationship between the intimal flap and the visceral artery origin in IVUS findings, and compared with routine examinations. Results The outer wall of the true lumen had a three layer structure while that of the false lumen had only one layer structure in IVUS imaging. There was an acute angle between the outer wall of the false lumen and the intimal flap at the true and false lumen junction. The thrombosis in the false lumen could be detected by IVUS. These features can assist in the differentiation of the true and false lumen. The relationship between the visceral artery origin and the true and false lumen could be determined in 81 out of 84 arteries, among which 54 were originated from the true lumen, and 27 from the false lumen. The detecting rate of visceral arteries by IVUS was 96.4%, higher than CT (70.2%) and DSA (84.5%),χ 2=20.74 and 6.91, P <0 01. Static narrowing in 6 arteries and dynamic narrowing in 1 artery were visualized by IVUS, while only 2 static narrowings could be detected by CT. Conclusions IVUS has an advantage over routine examinations at detecting visceral artery origin and clarifying the mechanism of visceral ischemia.