Application of Transcranial Doppler ultrasonography and Color Doppler ultrasonography in diagnosis of subclavain steal syndrome

Objective By observing the phenomenon of subclavain steal syndrome(SSS) with Transcranial Doppler ultrasonography(TCD)and Color Doppler ultrasonography(CDU),to analyze the diagnostic value of them in SSS.Methods 94 patients were diagnosed as SSS by TCD and CDU,11 of them were verified with digital substract angiography(DSA).Double MCA,ACA,PCA,VA and BA were examined with 2MHz probe of TCD.The lumen and intima-media of carotid,vertebral,subclacian and innominate arteries were displayed with two-dimensional ultrasonography and their blood flow velocity and direction were detected by color and spectral Doppler ultrasonography with LOGIQ BOOK computed sonography.According to the direction of ipsilateral VA (ip-VA),the subclavian steal syndrome (SSS) were defined as stage Ⅰ (deceleration in systole),stage Ⅱ(alteration flow with reversed flow in systole and normal flow in diastole) and stage Ⅲ ( reversed flow completely). The steal pathway was defined as basilar artery steal pathway (with steal waveform in basilar artery (BA) ) or non-basilar artery steal pathway (normal direction in BA).Results 88 patients of SSS were caused by atherosclerosis,6 patients by aortoarteritis.96 had subclavian arterial stenosis with lumen diameter 0.9～3.9mm and the velocity 150～500cm/s,occlusion of subclavian occurred in 4 patients 45% had steal stageⅠ,35% had steal stageⅡ,20% had steal stage Ⅲ.6 patients had basilar artery steal pathway and 2 patients had posterior cerebral arteryl steal pathway.Occlusion or nearly occlusion of subclavian were 4 patients with DSA.The severity of subclavain of 4 patients was 75%～95% and other 3 was 50%～74 %.Conclusion TCD combine with CDU is a sensitive and reliable method for evaluating the steal phenomena in patients with subclavian artery stenosis,they can not only observe the degree and path ways of steal phenomena,but also can indetify the etiopathogensis and severity of stenosis,and they are economic, convenient, no-injured,so they can be the first and foremost dignosis method for SSS, they also can be used to evaluate therapeutic effect and long-term follow-up.