Evaluation of focal carotid ischemia: will duplex scanning suffice, or is angiography needed?

We compared duplex scanning and cerebral angiography in patients with hemispheric ischemia, testing the premise that carotid endarterectomy (CEA) or medical management may be recommended on the basis of duplex scanning alone. Charts of 152 patients who had both studies were reviewed. A positive study (implying an operable lesion) showed any ulcerated plaque or stenosis of 50% to 99% on the symptomatic side. A positive duplex scan correctly predicted the need for CEA (with no additional essential information gained from angiography) more than 98% of the time. Equally important, patients with a negative duplex or patients in whom carotid occlusion is suspected ought to have angiography.