Neurologic symptoms associated with nonobstructive plaque at carotid bifurcation. Analysis by real-time B-mode ultrasonography.

Real-time B-mode ultrasonography was employed to image nonobstructive atherosclerotic plaque formation in the carotid artery bifurcation. Hemodynamic factors were assessed by pneumo-oculoplethsymography and Doppler flow study. Hemodynamically obstructive lesions were associated with a significantly higher incidence of cerebral ischemic symptoms than were nonobstructive plaques. Two types of nonobstructive plaques were delineated: isolated nodular plaques and mural plaques along the wall of the carotid sinus. Nodular plaques were associated with significantly fewer ischemic symptoms and strokes than were obstructive lesions. Mural plaques also had a lower incidence of symptoms than obstructive lesions, but the difference was not significant. Noninvasive determination of the morphologic and physiologic characteristics of atherosclerotic lesions at the carotid bifurcation can be of considerable value in the management of patients with transient ischemic attacks.