Transverse Sinus Dural Arteriovenous Fistula Presenting with Acute Hydrocephalus from Cerebellar Venous Engorgement Resolving with Endovascular Treatment.

A 77-year-old woman presented with a several week history of progressively worsening nausea and vomiting and a sudden change in mental status. She was found to have hydrocephalus with transependymal flow. Angiography revealed a Cognard class IIb/Borden class II transverse sinus dural arteriovenous fistula. Cerebellar venous engorgement causing posterior fossa mass effect was thought to be the cause of her hydrocephalus. Treatment involved transarterial embolization resulting in angiographic cure. Following treatment she had resolution of nausea and vomiting, and her ventriculostomy was discontinued without need for shunting. Six-month follow-up magnetic resonance imaging indicated no sign of hydrocephalus and significantly improved posterior fossa congestion.