CEREBRAL VASCULAR REACTIVITY ASSESSED WITH ACETAZOLAMIDE SINGLE-PHOTON EMISSION COMPUTER-TOMOGRAPHY SCANS BEFORE AND AFTER CAROTID ENDARTERECTOMY

BACKGROUND AND METHODS: In 64 patients, cerebral perfusion and vascula r reactivity were assessed before and after carotid endarterectomy (CE A) using acetazolamide (ACZ)-enhanced single photon emission computer tomography (SPECT). Twenty-five patients were asymptomatic, whereas th e remainder were symptomatic. Sixty-one patients had a greater than or equal to 70% ipsilateral internal carotid artery stenosis. RESULTS: F ifty SPECT scans revealed decreased vascular reactivity. Twenty-three showed infarcts. Fourteen patients had normal studies. Twenty of the S PECT scans of asymptomatic patients demonstrated poor vascular reactiv ity. After CEA, 39 patients had improved ipsilateral vasoreactivity. I n 12 patients, contralateral improvement was also found. CONCLUSION: A CZ-enhanced SPECT scans, by assessing cerebral perfusion and vascular reactivity, may help to identify patients at risk of stroke should per fusion further: diminish. Postoperative studies confirm improvement in vascular reactivity. ACZ-enhanced SPECT scans may provide objective e vidence for the selection of patients with a high-grade asymptomatic c arotid stenosis for CEA. (C) 1997 by Excerpta Medica, Inc.