Rare Variants of Carotid-Vertebrobasilar Anastomoses

Carotid-vertebrobasilar anastomoses generally disappear during embryogenesis. However, if a problem exists during regression, these arteries persist in adult period and are named as persistent arteries. Their persistence in adult patients is sometimes pathological and may result in the development of an aneurysm or a compressive syndrome. These anastomoses are frequently associated with proximal or distal arterial pathology. Herein, we present three rare variants of carotid-vertebrobasilar anastomoses: a persistent trigeminal artery, persistent hypoglossal artery, and a persistent otic artery. These variants should be kept in mind to avoid errors both in clinical reporting and surgical procedures.