Directional Doppler examination (DD) with flow registration over the supraorbital and supratrochlear arteries and over the carotid artery in the neck was adopted to 99 carotid arteries in 56 patients without previous knowledge of angiography results, and thereafter DD and angiography findings were compared. On subgrouping of the angiography results into internal carotid artery (ICA) stenosis less than 50%, greater than 50%, and occlusion, a correct diagnosis was obtained by DD on 90 vessels (91%). All 11 ICA occlusions were correctly diagnosed by DD. The incorrect results obtained with DD were as follows: Four ICA stenosis less than 50% were classified as stenosis greater than 50%; four stenosis greater than 50% were classified as less than 50%; one stenosis greater than 50% was classified as occlusion. DD is a useful noninvasive screening method for the detection of occlusion and greater than 50% stenosis of ICA.