Carotid artery imaging using duplex scanning and bidirectional arteriography: a comparison.

Examination of 101 common carotid bifurcations using ultrasonic methods is compared with the findings of transfemoral bidirectional arteriography. In the common and internal carotid arteries, ultrasonic detection of high-grade stenosis (greater than 50% reduction in lumen diameter) was 100% accurate (25/25) and detection of vessel occlusion was 85% accurate (11/13). In the two cases of occlusion missed on ultrasonography, a diagnosis of greater than 50% stenosis was made. Of lesions producing low-grade stenosis (less than 50% reduction in lumen diameter), 86% (78/91) were accurately detected using duplex imaging. In 33% (14/43) of common carotids and 13% (4/30) of internal carotids found to be angiographically normal, duplex scanning revealed the presence of plaque producing up to 25% stenosis, even in the absence of Doppler flow abnormality, confirming the sensitivity of high-resolution real-time imaging in detecting minimal disease.