COLOR-CODED DUPLEX SONOGRAPHY OF PREOCCLU SIVE CAROTID STENOSES

In a prospective study the results of 238 consecutive ultrasound exami nations of the carotid artery were correlated with angiography to test the reliability of colour coded duplex sonography in preocclusive car otid artery disease. This series was compared with a series of 611 ves sels with angiographically controlled conventional duplex sonography I n 61 resp. 84 cases stenoses greater-than-or-equal-to 90 % or occlusio ns of the internal carotid artery were found. The reliability of colou r coded duplex sonography for the diagnosis of greater-than-or-equal-t o 90 % stenoses was extremely high (sensitivity and specificity 98 %), as well as in preocclusive, > 95 % stenoses (100 % and 98 %), and for the diagnosis of occlusion, after exclusion of angiographic false pos itive diagnosis of occlusion (95 % and 99 %). Statistically colour cod ed flow imaging failed to increase significantly the high diagnostic s ensitivity or specificity of conventional duplex sonography, especiall y in preocclusive carotid artery disease. However, the remarkable incr ease in frequency of the diagnosis preocclusive stenosis with the intr oduction of colour coded Duplex Sonography probably reflects a higher sensitivity of this method. In addition the direct comparison of both ultrasound techniques showed a better image of the vessel wall abnorma lities and the residual lumen with colour coded duplex sonography.