Management of symptomatic posterior circulation flow aneurysms associated with agenesis of the internal carotid artery

Internal carotid artery agenesis, unilateral or bilateral is a rare congenital anomaly. Cerebral circulation challenged by this lack of anterior supply is compensated by increased flow through the posterior circulation and circle of Willis. This hyperdynamic circulation results in flow-related aneurysms, especially along the branching segments. We present the clinical, imaging and endovascular management of three symptomatic patients with discussion of relevant literature.