Arterial occlusion following anastomosis of the superficial temporal artery to middle cerebral artery.

Symptoms of cerebral ischemia following superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis are uncommon and are usually related to impaired flow through the anastomosis or occlusion of the cortical receptor artery. In this report, 3 patients are described who developed symptoms of cerebral ischemia after surgery despite a widely patent anastomosis. In each patient, postoperative angiography revealed occlusion of a previously demonstrated high-grade stenosis of the intracranial internal carotid artery (ICA) or MCA. Occlusion of the stenotic artery was probably related to decreased velocity of blood flow through the narrowed vessel resulting from alterations in flow patterns following anastomosis.