Persistent Primitive Trigeminal Artery Aneurysm: A Case Report

ABSTRACT

The persistent primitive trigeminal artery is the most common of the carotid-basilovertebral anastomoses and is located in the most cephalic portion of them. Embryologically arising from the internal carotid artery in the 4mm embryo, it supplies the longitudinal neural artery. Failure of regression of the trigeminal artery in the 14mm embryo results in the persistent primitive trigeminal artery. It is associated with a vascular anomaly in 25% of the cases, such as aneurysm, arteriovenous malformation, agenesis or hypoplasia of the internal carotid artery, and moyamoya disease. The authors present a case of persistent primitive trigeminal artery aneurysm presenting with the abducens nerve palsy. The clinical features of the persistent primitive trigeminal artery aneurysm are discussed, with the review of literature.