Patency and flow velocity profiles in the internal carotid artery assessed by digital subtraction angiography and Doppler studies three months following endarterectomy.

Pulsed Doppler spectral analysis and intravenous digital subtraction angiography have been carried out in 55 patients, three months after a total of 60 carotid endarterectomies. Five patients were operated on both sides and there were no re-operations. There were no re-stenoses and only one of the 60 internal carotid arteries was occluded. Spectral spreading of of the Doppler signal at the site of the endarterectomy was found in 52% of the internal carotid arteries, whereas wall irregularities were demonstrated in 25% by intravenous digital subtraction angiography. A stenosis or occlusion was found in 11 (18%) of the 60 ipsilateral external carotid arteries.