Arteriovenous Malformation

Types

Enlarge

Dural Arteriovenous Fistulas

Dural arteriovenous fistulae (DAVF) are abnormal connections between arteries in the scalp and dura (the tough covering over the brain) and a draining vein or sinus. Like an AVM, arterial blood passes directly into veins. This type of malformation may cause the patient to hear an aggravating noise (pulsatile tinnitus). The DAVF may cause blood to back up into the adjacent brain or spinal cord and cause numbness or weakness. Another possibility is that the arteries or veins can rupture and cause a brain hemorrhage. However, because the blood vessel malformation is in the dura rather than in the brain or spinal cord itself, these lesions are usually not as dangerous and are easier to treat than other types of AVMs.

Stereotactic radiosurgery followed by embolization of accessible external carotid artery feeding vessels is the primary mode of treatment for most DAVFs at Mayo. Radiosurgery generally obliterates DAVFs between one and three years after treatment.