Dural Arteriovenous Fistulae at the Craniocervical Junction: The Relation Between Clinical Symptom and Pattern of Venous Drainage

Abstract
Background: Dural arteriovenous fistula (DAVF) at the craniocervical junction is an unusual condition with alternative presentations and is a rare cause of intracranial subarachnoid hemorrhage (SAH). We performed a retrospective, angiographic study of six consecutive patients to assess the relation between symptom and venous drainage and to predict the risk for SAH. Methods: There were three females and three males; ages ranged between 37 and 64 with a mean of 52.5. Among them, four had SAH and two had pain. Diagnosis of DVAF was based on CTA, MRA and angiograph. Results: Three patients (50%, 3/6), with single or main ascending venous route into the intracranial vein, all had intracranial SAH. Among these three patients, varix or pouches was identified in two cases (66.7%, 2/3). Three cases were treated by surgical interventions, while two subjects were endovascular techniques. The overall clinical outcomes were good during an average follow-up period of 13 months. In particular, follow-up angiographs performed 6 months later revealed the complete disappearance of DAVF in three patients. Conclusions: There was an increased risk of SAH if DAVF at the craniocervical junction manifested an ascending venous route into the intracranial vein and/or presented with varix or pouches.