Last Updated: October 1, 2018
Arteriovenous fistulas (AVFs) are direct pathologic arteriovenous shunts representing 10-15% of all cerebrovascular malformations with AV shunting. The prototypical AVF is an acquired lesion between transosseous-extracranial and/or meningeal arteries into the wall of a thrombosed dural venous sinus compromising a dural AVF (DAVF) and resulting in hypertensive venous congestion and venopathy, however pathologic arteriovenous fistulous connections may exist along any dural margin, sinus, or venous tributary.
DAVFs are distinguished from pial-parenchymal arteriovenous malformations by the predominance of dural arterial supply and the absence of a parenchymal nidus, however AVMs may have pial or dural fistulous components. The majority of DAVFs present in adulthood and are most commonly located at the transverse-sigmoid sinus wall. Clinical presentation and imaging findings are highly variable depending on anatomic site, degree of AV shunting, and venous reflux.
Transverse-sigmoid sinus DAVFs typically present with pulsatile tinnitus. DAVFs may present with encephalopathic symptoms secondary to venous hypertension, ischemia, and/or thrombosis. DAVFs with deep/inferior drainage to the petrosal sinuses and perimedullary venous plexus may result...