Trauma to the high cervical carotid artery.

An alternative approach to the treatment of distal extracranial nonoccluding internal carotid artery penetrating injuries is described in which internal carotid artery ligation is followed expectantly. A warning transient neurologic deficit prompted an unsuccessful attempt at revascularization via a superficial temporal artery to middle cerebral artery anastomosis. The failure of the anastomosis was thought to be secondary to a postinjury hypercoagulable state and a diminished demand for intracranial blood flow secondary to an unexpected, impressive development of collateral blood supply.