Extracranial surgery for the low-flow-endangered brain

R. H. Whitten, W. Gee, H. A. Kaupp and K. M. McDonald

Angiography documented severe (greater than 75%, cross-sectional area) bilateral carotid stenotic or occlusive disease in 60 patients. One third of these patients were thought to have transient ischemic symptoms of low-flow rather than embolic etiology. Preangiographic ocular pneumoplethysmography (OPG-Gee) was obtained in all patients. Postoperative OPG studies were obtained in the 39 patients who underwent unilateral carotid surgery. In seven of the 39 patients who were operated on, bilateral procedures were performed; OPG studies were obtained after the second procedure also. Comparison of the preoperative and postoperative OPG studies provided convincing evidence that the establishment of major carotid inflow should be the primary objective in patients with severe bilateral carotid disease, and that distal extracranial-intracranial reconstruction should be reserved for patients failing to respond to augmented inflow because of deficient collateral vessels.