Dural Arteriovenous Fistula: Symptoms and Endovascular Treatment

A dural arteriovenous fistula is an abnormal connection between arteries and veins in the covering of the brain or spinal cord. Symptoms vary widely, but many cases can be diagnosed with vascular imaging and treated with minimally invasive endovascular techniques.

Overview

A dural arteriovenous fistula, often shortened to dAVF, is an abnormal connection between arteries and veins located in the dura mater, the tough outer covering of the brain or spinal cord. In a normal circulation pattern, blood travels from arteries into very small capillaries and then into veins. In a dAVF, blood bypasses this usual pathway and flows directly from arteries into veins, which can create increased pressure in nearby veins.

These fistulas are different from other vascular malformations of the brain. They are not usually found within the brain tissue itself, but rather in the covering around it. Even so, they can still affect brain function if abnormal venous drainage causes congestion, reduced normal blood flow, or bleeding. Some dAVFs remain relatively stable, while others carry a higher risk of neurological complications.

The impact of a dAVF depends on its location, size, and especially the way blood drains from it. A fistula near the ear may cause a rhythmic sound, while one that drains into veins on the brain surface can lead to more serious symptoms. Because of this, treatment decisions are based not only on symptoms but also on imaging findings and overall risk.

Symptoms

Symptoms of a dural arteriovenous fistula can vary greatly. Some people have mild or subtle complaints, while others develop urgent neurological problems. One of the best-known symptoms is pulsatile tinnitus, a rhythmic whooshing or heartbeat-like sound in the ear. This can happen when the fistula is near veins and sinuses around the ear and skull base.

Other symptoms may include headaches, pressure behind the eye, redness of the eye, double vision, vision loss, dizziness, memory or concentration problems, or weakness and numbness. In spinal dAVFs, symptoms often relate to the spinal cord and may include leg weakness, numbness, balance problems, or changes in bladder and bowel function. Symptoms can develop gradually or suddenly depending on how the veins are affected.

In higher-risk fistulas, blood drains backward into veins on the brain surface, causing venous congestion or increasing the chance of bleeding. This may lead to seizures, confusion, difficulty speaking, stroke-like symptoms, or intracranial hemorrhage. For this reason, symptoms that seem non-specific should still be assessed carefully when a vascular cause is suspected.

• Pulsatile tinnitus
• Headache
• Eye pain, redness, or visual changes
• Seizures
• Weakness, numbness, or balance problems
• Confusion or cognitive changes
• Sudden neurological symptoms or bleeding

Causes and Risk Factors

The exact cause of many dural arteriovenous fistulas is not always clear. Unlike some congenital vascular malformations, dAVFs are often considered acquired lesions. They may develop after changes in venous drainage within the dura, sometimes related to clotting of a venous sinus, head trauma, previous surgery, infection, or rarely hormonal and vascular changes that affect the vessel walls.

One proposed mechanism is that when normal venous outflow becomes blocked or altered, new abnormal vessel connections form between small dural arteries and veins. Over time, these channels may enlarge and produce symptoms. Not every person with a venous sinus problem will develop a dAVF, but disturbed venous flow appears to play an important role in at least some cases.

Risk is not determined only by whether a fistula exists, but by its behavior. Fistulas that drain into a dural venous sinus without dangerous backflow may cause bothersome symptoms yet carry a lower risk. In contrast, fistulas with cortical venous drainage, venous ectasia, or evidence of prior bleeding are treated more urgently because they are more likely to result in hemorrhage or progressive neurological injury.

Diagnosis

Diagnosis usually begins with a careful medical history and neurological examination. A doctor may ask about pulsatile tinnitus, headaches, visual changes, fainting, seizures, or any symptoms that suggest spinal cord involvement. Because these symptoms can overlap with other conditions, imaging is essential to confirm the diagnosis and understand the exact anatomy.

MRI and MR angiography can help show abnormal flow patterns, enlarged vessels, brain swelling, or signs of venous congestion. CT and CT angiography may also be used, especially if there is concern about bleeding. In some people, these scans strongly suggest a dAVF, but they may not fully map the lesion or show every feeding artery and draining vein.

The most important test for detailed diagnosis is catheter cerebral angiography, sometimes called digital subtraction angiography. During this procedure, a specialist inserts a thin catheter into a blood vessel and injects contrast dye to visualize blood flow in real time. This test remains the gold standard because it shows the exact location of the fistula, the arteries feeding it, the venous drainage pattern, and whether high-risk features are present. It also helps the care team plan whether embolization or another treatment approach is most appropriate.

Endovascular Treatment Options

Endovascular treatment is one of the main ways to manage a dural arteriovenous fistula. It is a minimally invasive technique performed from inside the blood vessels, usually through a small puncture in the wrist or groin. Using X-ray guidance, the specialist advances fine catheters to the arteries or veins connected to the fistula and delivers materials that block the abnormal connection.

This treatment is often called endovascular embolization. Depending on the fistula anatomy, the doctor may approach it through an artery, a vein, or both. Materials used can include liquid embolic agents, coils, or other devices chosen to close the fistula while preserving normal circulation as much as possible. The aim is to stop the abnormal shunting and relieve dangerous venous pressure.

Not every dAVF can be treated in exactly the same way. Some are cured with a single endovascular session, while others need staged procedures, surgery, or radiosurgery if the anatomy is complex or if a small residual fistula remains. In selected cases, a multidisciplinary team may compare endovascular therapy with Gamma Knife radiosurgery or brain surgery to achieve the safest and most complete result.

After treatment, follow-up imaging is important because symptom improvement does not always guarantee complete closure. Some people notice rapid relief of pulsatile tinnitus or pressure symptoms, while neurological recovery after venous congestion can take longer. The treating team will advise on recovery, medication needs, and the timing of repeat angiography or MRI to confirm durable closure.

Prevention, Self-care, and Recovery

There is no guaranteed way to prevent a dural arteriovenous fistula, because many arise without a clearly preventable cause. Still, prompt evaluation of unusual symptoms such as pulsatile tinnitus, new neurological changes, or unexplained eye symptoms can help identify the condition before complications develop. Early diagnosis matters because timely treatment can reduce the risk of bleeding or progressive neurological damage.

Self-care before diagnosis should focus on observation and medical follow-up rather than trying to manage symptoms alone. Over-the-counter pain medicines may help headache in some people, but persistent or changing symptoms should not be ignored. Any sudden worsening, severe headache, seizure, or stroke-like symptom needs urgent assessment.

Recovery after endovascular treatment depends on the fistula location, the complexity of the procedure, and whether there was prior bleeding or injury to the brain or spinal cord. Many patients are able to resume light activities fairly soon, but the exact timeline should be guided by the treating specialist. Follow-up appointments are essential to make sure the fistula stays closed and to address any lingering symptoms such as headache, fatigue, or tinnitus.

For patients seeking coordinated international care, Acibadem International’s multidisciplinary specialists and JCI-accredited hospitals evaluate and treat complex neurovascular conditions, including dural arteriovenous fistula, with individualized planning and follow-up.

When to See a Doctor

Medical review is important for any persistent pulsatile tinnitus, unexplained neurological symptoms, progressive weakness, new visual changes, or unusual headaches that do not have a clear cause. These symptoms do not always mean a dAVF is present, but they deserve assessment, particularly if they are new, worsening, or affecting daily life.

Urgent medical care is needed for warning signs such as a sudden severe headache, seizure, fainting, confusion, weakness on one side, trouble speaking, loss of vision, or difficulty walking. These symptoms may indicate brain bleeding, significant venous congestion, or another neurological emergency. Spinal symptoms such as rapidly worsening leg weakness or loss of bladder control also need immediate attention.

Because dAVFs vary so much in risk, specialist evaluation is valuable even when symptoms seem mild. Doctors with expertise in neurovascular and endovascular care can determine whether the fistula is low-risk and suitable for monitoring or whether treatment is recommended to prevent future complications. Clear diagnosis and follow-up help patients make informed, reassuring decisions about care.

Frequently asked questions

Is a dural arteriovenous fistula the same as an AVM?

No. A dural arteriovenous fistula is an abnormal connection in the dura, the covering of the brain or spinal cord, while an arteriovenous malformation usually has a tangle of abnormal vessels called a nidus. They are related vascular disorders, but they differ in structure, behavior, and treatment planning.

Can pulsatile tinnitus be caused by a dural arteriovenous fistula?

Yes. A dAVF near the venous sinuses around the ear can produce a rhythmic whooshing sound that matches the heartbeat. Because pulsatile tinnitus can also have other causes, it should be evaluated by a qualified doctor, especially if it is persistent or new.

Is endovascular treatment a surgery?

Endovascular treatment is minimally invasive rather than open surgery. It is performed through a small blood vessel access site using catheters and imaging guidance. In some cases, however, open surgery or radiosurgery may still be needed depending on the fistula’s anatomy.

Are all dural arteriovenous fistulas dangerous?

Not all dAVFs carry the same risk. The most important factor is how the abnormal blood drains, especially whether there is cortical venous drainage or prior bleeding. Some lesions are lower risk and may be monitored, while others need prompt treatment.

Can a dural arteriovenous fistula come back after treatment?

It can, although many fistulas are successfully closed. Follow-up imaging is important because a small residual connection may persist or, less commonly, recur over time. The treating team will recommend the right follow-up schedule based on the individual case.

What doctor treats a dural arteriovenous fistula?

Care is often provided by a multidisciplinary team that may include an interventional neuroradiologist, endovascular neurosurgeon, neurologist, and neurosurgeon. The exact specialists involved depend on the fistula’s location, symptoms, and whether treatment is endovascular, surgical, or combined.

References

• World Health Organization
• National Institute of Neurological Disorders and Stroke
• American Heart Association
• Radiological Society of North America
• National Health Service

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.