Transient postoperative occlusion of the superficial temporal--middle cerebral artery branch anastomosis: spasm, swelling, or thrombosis.

Ten superficial temporal-middle cerebral artery branch anastomoses were followed by postoperatvie angiograms. The early angiograms revealed patent anastomosis in six patients. In two patients the superficila temporal artery was severely narrowed and tapered and the cerebral arteries were not visualized. In one the superficial temporal artery was not significantly narrowed but was only patent extracranically. In the remaining patient, the superficial temporal artery was completely occluded. The late angiograms showed the patency of the six originally patent anastomoses, and also complete patency of the three anastomoses in which the cerebral arteries were not visualized.