Failure of extracranial-intracranial arterial bypass in acute middle cerebral artery occlusion: case report.

Extracranial-intracranial arterial bypass procedures provide important augmentation of collateral circulation to cortical areas rendered potentially ischemic by therapeutic occlusion of major branches of the circle of Willis. Although the case studies reported to date in general reflect positively on this use of the bypass procedure, this report of a patient who failed to tolerate acute middle cerebral artery occlusion despite the presence of a patent superficial temporal-middle cerebral artery branch anastomosis points up several of the practical and theoretical limitations of this therapeutic approach. Certain modifications of the timing of the bypass procedure, the selection of donor and recipient arteries, and the mechanics of intracranial arterial occlusion may allow a wider application of extracranial-intracranial arterial bypass in this therapeutic setting.