Henry Ford Hospital Medical Journal


We studied the effect of the superficial temporal artery to middle cerebral artery bypass (STA-MCA) procedure on neuropsychological function. Nineteen patients with cerebrovascular disease of the anterior carotid circulation (12 on surgical and seven on medical therapy) received an extensive battery of neuropsychological tests; the average test-retest interval was eight weeks. Both groups improved on some measures, and no patients deteriorated. There was no evidence of greater improvement by the surgical group. The results are compatible with a spontaneous remission/practice effect interpretation. A review of the carotid endarterectomy and STA-MCA bypass literature suggests that the null hypothesis of no effect on the patient's neuropsychological abilities after cerebrovascular surgery has not been disproved; it is clear that the average patient does not improve. Further study of individual differences may show that certain types of patients improve. In future research, nonoperated comparison subjects should also have cerebrovascular disease.