Behavioral effects of superficial temporal artery to middle cerebral artery bypass surgery: preliminary report.

We studied the neuropsychologic effect of the superficial temporal artery to middle cerebral artery bypass procedure. Nineteen patients with disease (12 surgical and 7 medical therapy) of the anterior carotid circulation were evaluated by neuropsychologic tests with an average test-retest interval of 8 weeks. The 12 surgical and 7 medical patients were comparable in age, education, and preoperative test scores. All surgical patients achieved patency of anastomosis. Both groups improved on some measures and there were no significant differences between groups over time. No patients have deteriorated. The results were compatible with either a spontaneous remission or a practice effect interpretation.