De Novo Formation of a Carotid Web in an Adult: A Longitudinal Observation.

BACKGROUND: Carotid web is a thin shelf-like fibrointimal membrane arising from the posterior or posterolateral wall of the carotid bulb. Webs cause stroke, especially in younger adults with high risk of recurrence.

METHODS: To report the first case of de-novo formation of an asymptomatic carotid web and describe longitudinal clinical-angiographic follow-up.

RESULTS: A previously healthy 50-year-old White female presented with acute vestibular syndrome. Brain MRI showed no infarction. An arch-to-vertex CT angiogram showed normal posterior circulation, however, the left internal carotid artery bulb had a thin shelf-like projection into the lumen arising from the posterior wall of the artery - an incidental carotid web. A CT angiogram performed seven years earlier showed normal carotid arteries. The three-year angiographic follow-up showed an unchanged angiographic appearance of the carotid web. The patient preferred staying on aspirin and suffered no retinal or cerebral ischemic event during the 5-year clinic follow-up.

CONCLUSION: Our case suggests de novo (acquired) formation of a carotid web in an adult. This challenges the prevailing theory that carotid web is a congenital/developmental lesion.