A Case with a TWIST: Not so Benign Type 1 Dural Arteriovenous Fistula

Dural arteriovenous fistula (DAVF) is a vascular anomaly formed by a pathologic connection between dural arteries and venous sinuses (1). Type I DAVFs are considered benign lesions since they drain directly into the dural venous sinuses with antegrade flow. Types II and higher are categorized as aggressive. They are characterized by retrograde flow and reflux into cortical veins which increase the risk of intracranial hemorrhage (2,3). Previous case series have described symptoms of idiopathic intracranial hypertension (IIH) as the initial presentation for DAVF (4,5). Most patients in the case series had aggressive DAVFs. We present a patient with type I DAVF with visual impairment from intracranial hypertension.