Dural arteriovenous fistulae (dAVF)

Cerebral AngiogramWhat is a Dural Arteriovenous Fistula?

The dura is a protective layer covering the brain and spinal cord. It functions as a safeguard for the nervous system beneath the bone covering of the skull and spine. Embedded within this brain covering, dural arteriovenous fistulas (dAVFs) are a specific type of vascular malformation that can affect the brain and spinal cord due to abnormal connections between arteries and veins. These uncommon vascular malformations occur at an incidence rate of 1-2 per 10,000 people each year.

Symptoms

A dural arteriovenous fistula can present with a wide variety of neurological symptoms, depending on its location and severity. Most commonly, the fistulas affecting the brain covering are located near the ear canal. Due to the constant high flow of pulsatile blood, patients frequently report a whooshing sound that corresponds to heartbeats—also known as pulsatile tinnitus. Depending on the location and aggressiveness of the fistula, symptoms can also include cognitive decline, worsening headaches, visual disturbances such as double vision, abnormal eye movements, eyeball swelling (proptosis), cognitive impairment resembling dementia, weakness, numbness, and changes in bladder and bowel control. Occasionally, fistulas can cause increased pressure in the brain and spinal cord, leading to severe injury that may result in bleeding, also known as a hemorrhagic stroke.

Diagnosis

Diagnosing a dural arteriovenous fistula can be very challenging, depending on its presentation. Specific types of CT or MRI scans can detect dAVFs, although often they cannot be identified with these modalities alone. The gold standard test for evaluating a dAVF is conventional cerebral or spinal digital subtraction angiography (DSA).

Treatment Options

Timely diagnosis, accurate characterization, and multidisciplinary treatment planning are crucial for the management of dAVFs. Low-risk fistulas that do not cause disabling symptoms can be safely observed with surveillance imaging. Depending on the location, the probability of adverse effects on the brain and spinal cord, and the risk of complications, treatment options include; endovascular embolization, surgical resection or radiosurgery. It is important for patients to discuss these options with their healthcare provider to understand the best course of action tailored to their specific condition.

How Can We Help You?

The multi-disciplinary team at The Hartford HealthCare Neurovascular Program offers the full spectrum of care for patients with dural arteriovenous fistulas, from diagnosis, to treatment, to lifelong follow up and support. Our experienced team of specialists includes fellowship-trained neurosurgeons, vascular neurologists, neuroradiologists, and subspecialized physician assistants, advanced practice registered nurses, and therapists.

Ayer Neuroscience Institute