Carotid endoarterectomy (CEA) is known to prevent cerebrovascular accidents. Between February 1987 and December 1993 we performed 97 CEA on 82 patients (62 male and 20 female, median age 66 +/- 7.6 years) 95.1% reported previous hemispheric neurological accidents; 4.9% were asymptomatic. Operative indications for asymptomatic patients were high degree stenosis (> 70%) of the internal carotid artery and ulcerated plaques with a moderate degree (50%) of stenosis. Major events (transient ischemic attack and stroke) were recorded in 73.2% cases. Preoperative investigations consisted of Duplex scan, arteriography, and cerebral CT scan or NMR. Operative mortality was 2.06% (2 cases) and perioperative stroke was 5.1% (5 cases). The sensibility, sensitivity and accuracy of Duplex scan to detect ulcerated plaques was 88.7%, 85.2% and 87.5% respectively. At a median follow-up of 33 months (range 6-81 months) 74 (92.5%) patients are free of strokes whereas 1 patient died for stroke. In our series the annual incidence of stroke was 0.5%. Our results suggest that Duplex scan is a reliable exam to investigate the carotid axis and CEA is a safe operation that prevents future cerebrovascular accidents.