Accurate noninvasive method to diagnose minor atherosclerotic lesions in carotid artery bulb.

In a prospective study using a multigate pulsed Doppler system, minor (less than 30% diameter reduction) carotid artery lesions were diagnosed by detecting not only abnormalities in the blood flow pattern, but also local changes in artery wall distensibility. For the diagnosis of more severe lesions, additional information was obtained from disturbances in the Doppler audio spectrum. Biplane arteriography was used as a reference. The observed agreement, sensitivity, and specificity were 86.6%, 90.3%, and 88.6%, respectively, for all lesions and 85.7%, 82.1%, and 88.6%, respectively, when only minor lesions were considered. kappa (a chance-corrected measure of agreement) was 81.7%. If only blood flow abnormalities were used to detect minor lesions, 43.5% would be missed. Our results indicate that minor carotid artery lesions can be diagnosed noninvasively more accurately when both local blood flow irregularities and local changes in vessel wall distensibility are taken into account.