HIGH-GRADE STENOSIS OF THE INTERNAL CAROTID-ARTERY ASSESSED BY COLOR AND POWER DOPPLER IMAGING

Purpose. Visualization of carotid artery stenosis is important to impr ove our understanding of the etiology of ischemic stroke. Two sonograp hic methods are available for visualizing carotid stenosis: power Dopp ler imaging (PDI) and color Doppler imaging (CDI). The purpose of this study was to compare the advantages and limitations of these methods in the evaluation of internal carotid artery (ICA) stenosis. Methods. Thirty-two patients with at least 70% extracranial ICA stenosis were i ncluded in this prospective study. All subjects were examined with CDI and PDI. Four criteria were used to evaluate diagnostic accuracy and overall efficacy: identifying the target vessel, determining the causa l pathology, evaluating blood flow, and the examiner's confidence in t he diagnosis. Results. All patients had high-grade stenosis (17 patien ts had 70% stenosis, 11 had 80%, 2 had 90%, and 2 had pseudo-occlusion s of the ICA). PDI was significantly (p < 0.05) superior to CDI in ide ntifying the target vessel and highly significantly (p < 0.01) superio r to CDI in evaluating blood flow. There were no significant differenc es between CDI and PDI in determining the causal pathology or in the e xaminer's confidence in the diagnosis. Conclusions. This study demonst rates that PDI is a good additional method to CDI and should be used w ith it to evaluate ICA stenosis. (C) 1998 John Wiley & Sons, Inc.