Clinical application of angioscopy during carotid endarterectomy for patients with internal carotid artery stenosis.

The accuracy of angioscopy in detecting atherosclerotic changes, such as plaque, ulcer, and mural thrombus, in the extracranial cerebral arteries was evaluated during carotid endarterectomy by comparison with angiographic and operative findings. Ten patients with internal carotid artery stenosis underwent intraoperative angioscopy during surgery. After clamping the carotid bifurcation, intra-arterial atherosclerotic lesions were observed with an angioscope (0.8 or 1.4 mm outer diameter) inserted through a small incision in the common carotid artery. Angioscopic findings correlated well with both angiographic and operative findings in six patients, and provided additional information in two patients, such as organized thrombi within the ulcer and mural thrombi. Angioscopic findings were quite different to those from angiograms in two patients. In one, an ulcer on angiograms was false positive, and in the other, false negative. These findings were confirmed intraoperatively. Our results suggest that preoperative carotid angioscopy is of great value in detecting ulcers more accurately than angiography, and in selecting candidates for carotid endarterectomy, although further development of equipment is needed.