ROLE OF DUPLEX SCANNING IN THE SELECTION OF PATIENTS FOR CAROTID ENDARTERECTOMY

A retrospective review of 63 patients undergoing duplex scanning and angiography for suspected carotid artery disease was performed to evaluate the need for routine angiography before carotid endarterectomy. A consultant surgeon (M.H.) made a simulated management decision on the basis of a clinical summary and a duplex scan report. Twenty‐four patients were selected for surgery without angiography; duplex scanning had a sensitivity of 100 per cent and a specificity of 90 per cent in the detection of internal carotid artery stenosis. In two cases duplex scanning misdiagnosed a total occlusion as a critical stenosis. Eighteen patients failed to meet the criteria for surgery and were referred for angiography. Twenty‐one patients were selected for conservative treatment on the basis of the duplex scan report. Combining the surgical and conservative groups (45 patients), duplex scanning had a sensitivity of 96 per cent and specificity of 95 per cent for the detection of stenosis greater than 50 per cent. In the identification of a total occlusion, duplex scanning had a poor sensitivity of 50 per cent. These results suggest that routine angiography before carotid endarterectomy is unnecessary in selected patients but that a suspected occlusion should be confirmed by angiography. Copyright © 1990 British Journal of Surgery Society Ltd.