Bilateral occipital infarctions associated with carotid stenosis in a patient with persistent trigeminal artery. The Collaborators of the North American Carotid Endarterectomy Trial (NASCET).

BACKGROUND Embolization via a persistent trigeminal artery, one of the embryonic vascular connections that may persist between the carotid and basilar arteries, is an unusual occurrence. CASE DESCRIPTION We describe a 76-year-old man with bilateral occipital infarctions presumably related to an ulcerated left carotid stenosis. Clinically, a left inferior homonymous quadrantanopia was present. CONCLUSIONS Anomalous connections between the carotid and the usual posterior circulation territory should be considered in evaluating patients with vertebrobasilar stroke. When they are identified, patients with symptoms attributable to the pontine vertebrobasilar territory supplied by the anomaly may be considered for carotid endarterectomy in the presence of concomitant severe carotid stenosis detected angiographically. Proper identification and treatment of such cases would be expected to prevent recurrence of disabling strokes in the vertebrobasilar circulation. These anomalies will likely be overlooked by ultrasound techniques and depend on good intracranial arteriographic images.