Unruptured dural arteriovenous malformation of the transverse-sigmoid sinus presenting with focal symptoms and coma

We are presenting the case of a 63 year-old man with a dural arteriovenous malformation of the transverse sigmoid sinus who developed focal deficits followed by less localized symptoms such a disorientation, lethargy and eventually comatose status. Initial cerebral angiography showed retrograde filling of the cortical and deep cerebral venous system with marked delay in venous empting. Following embolization clinical symptoms completely cleared at the time that control angiography showed retrograde venous flow turning anterograde. Patient's symptoms recurred four months later when there was a relapse of retrograde cerebral venous drainage at the time he developed thrombosis of the superior longitudinal and right transverse sinuses. Sinus thrombosis and thrombosis of the central retinal artery were coincidental with hypercoagulability related to hyperhomocysteinemia. Since control angiography still showed persistence of the AV shunting radical excision of the involved dural sinuses was performed. The final outcome was excellent. The physiopathological mechanism responsible for neurological deficits in our patient most likely was ischemia of venous origin secondary to venous hypertension resulting from retrograde cerebral venous drainage. The clinical and angiographic presentation in few similar cases reported in the literature is reviewed.