Accurate Diagnosis of Carotid Artery Stenosis: Ultrasound

Abstract

The advantages of carotid sonography are its capabilities to obtain morphological information such as stenosis or ulceration and to permit the speculation of tissue characterization. Morphological aspect: Our data suggest that the degree of stenosis from color coded Dopper imaging tends to be underestimated as compared with that estimated by angiography, because the sonography from color-coded Doppler goes over the artery wall, especially in severe stenosis. However, the accuracy of identifying carotid artery stenosis by carotid sonography is above 90% by combined use of the criteria from peak systolic velocity. Tissue characterization: The plaques are classified into echolucent, echogenic or hyperechoic from the echogenecity, and into homogeneous or heterogeneous from its context. Echolucent plaque reflects hemorrhage or atheroma, echogenic plaque reflects fibrosis, and hyperechoic reflects calcification. The classification should be based on the quantitative analysis, because the judgment of echogenecity is influenced by the instruments used and used sonographers themselves.