Cerebral Dural Arteriovenous Fistulas

Dural arteriovenous fistulas (DAVF), also called dural arteriovenous malformations, account for 10-15% of all intracranial vascular malformations with AV-shunt. DAVF are pathologic shunts between dural arteries and dural venous sinuses, meningeal or cortical veins. Most frequently, DAVF are located within the wall of the transverse, sigmoid, cavernous, sagittal superior sinus or within the cerebellar tentorium. Whereas in many cases no underlying pathomechanism is found, thrombosis of venous vessels, inflammatory processes and trauma have been listed as underlying causes. Depending on localization of the fistula, shunt volume, and venous drainage pattern, the clinical presentation of patients ranges from asymptomatic to severe neurological deficits. Dural AVF can be graded using the classifications of Cognard et al. or Borden et al., both of which stratify the lesions with special emphasis on venous drainage patterns, as cortical venous drainage has been found to be associated with an increased risk for intracranial haemorrhage. The indication to treat a DAVF thus mainly depends on the patients' clinical presentation as well as the venous drainage pattern. Carotid cavernous fistulas likewise are DAVF, but since more frequently they are traumatic, they are categorized according to Barrow et al. Treatment options include (transvenous and/or transarterial) endovascular approaches, neurosurgery, and radiosurgery. A combination of the afore- mentioned treatment modalities is feasible. Thus, treatment of DAVF should be performed in a neurovascular center with close interdisciplinary cooperation of a team of neurologists, neuroradiologists, neurosurgeons, and radiotherapists.