CONSISTENCY OF DOPPLER PARAMETERS IN PREDICTING ARTERIOGRAPHICALLY CONFIRMED CAROTID STENOSIS

Background and Purpose While internal carotid peak systolic velocity ( IPSV) is reportedly the best Doppler parameter for predicting lower gr ades of carotid artery stenosis, the internal carotid end-diastolic ve locity (IEDV) or the ratio of IPSV to common carotid end-diastolic vel ocity (CEDV) is helpful in increasing prediction of higher grade steno ses. It is important to examine the consistency of these findings acro ss machine and technician. Methods Using data from 10 devices from the Asymptomatic Carotid Atherosclerosis Study, we examined the predictiv e ability of seven Doppler parameters: IPSV, IEDV, CEDV, common caroti d peak systolic velocity (CPSV), and the ratios of IPSV/CEDV, IEDV/CED V, and IEDV/CEDV. To assess the agree ment between Doppler and arterio graphy in classifying percent stenosis above or below a given criterio n, sensitivity, specificity, area under the receiver operating curve, and kappa statistics were obtained from logistic models. The single be st Doppler parameter for each of two grades of stenosis (60% and 80%) was determined, and its predictive ability was compared with that of I PSV. The usefulness of IEDV or IPSV/CEDV in addition to IPSV to determ ine higher grade stenosis was examined. Results IPSV was the best pred ictor in 9 of 10 devices at 60% and in 4 devices at 80% stenosis. When another parameter was better than IPSV, the improvement was minimal. Including IEDV or IPSV/CEDV in addition to IPSV did not notably improv e predictive ability. Conclusions IPSV is the single best Doppler para meter for distinguishing severe (>80%) from less severe carotid stenos is. Information from other Doppler parameters in addition to IPSV is u nlikely to be helpful.