Results of extracranial-intracranial arterial bypass for bilateral carotid occlusion.

The results of superficial temporal to middle cerebral artery bypass surgery for bilateral internal carotid artery occlusion were reviewed in 39 patients. Preoperative symptoms included recurrent transient ischemic attacks (TIA's) in 31 patients (80%) and mild or moderate stroke in 15 (29%). Deficits were unilateral in 23 cases and bilateral in 14. Dementia or personality changes were observed in 19 patients (49%). Operative morbidity occurred in six of 39 cases and was neurological in one; the surgical mortality rate was 8% (three of 39 patients), including two cases of cerebral hemorrhage. The outcome was good or excellent (relief of TIA's and reduction of neurological deficit) in 82% of patients over a follow-up period of 3 to 139 months. Five patients had a late postoperative stroke, which occurred in the unoperated hemisphere in each case; one patient had an ipsilateral TIA 6 years after the bypass procedure. These results suggest that an extracranial-intracranial arterial bypass procedure to augment collateral cerebral blood flow can be performed safely in patients with bilateral internal carotid artery occlusion and may be associated with relief of ischemic symptoms. Future studies may document a role for this procedure in the prevention of stroke.