Dural Arteriovenous Fistula: Pulsatile Tinnitus, Imaging, and Endovascular Treatment

A dural arteriovenous fistula is an abnormal connection between arteries and veins in the tough outer covering of the brain or spine. It can cause pulsatile tinnitus, headaches, eye symptoms, or neurological changes, and many cases can be treated with modern endovascular techniques.

Overview

A dural arteriovenous fistula, often shortened to dAVF, is an abnormal connection between an artery and a vein within the dura mater. The dura is the strong outer membrane that surrounds the brain and spinal cord. In a dAVF, blood flows directly from high-pressure arteries into veins or venous sinuses, bypassing the normal small blood vessels called capillaries.

This abnormal flow can create turbulent blood movement and increased pressure in nearby veins. Depending on where the fistula is located, a person may notice a rhythmic sound in the ear, headaches, eye redness, vision changes, or neurological symptoms. Some dAVFs are low risk and may be monitored, while others require treatment because of the way they drain into brain or spinal veins.

Dural arteriovenous fistulas are different from brain arteriovenous malformations, which are usually congenital tangles of vessels within brain tissue. A dAVF is typically located in the dura and often develops later in life. Care is usually coordinated by neurologists, neurosurgeons, neuroradiologists, and neurointerventional specialists.

Pulsatile Tinnitus and Other Symptoms

One of the most recognized symptoms of a dural arteriovenous fistula is pulsatile tinnitus. This is a whooshing, thumping, or heartbeat-like sound that often occurs in one ear and matches the pulse. It may be more noticeable when lying down, during quiet moments, or after exercise. Some people can reduce the sound temporarily by gently pressing on the neck, but this is not a diagnostic test and should not be used repeatedly.

Symptoms vary according to the location of the fistula and the direction of venous drainage. A fistula near the transverse or sigmoid sinus may cause pulsatile tinnitus. A fistula near the cavernous sinus, behind the eye, may lead to a red or swollen eye, double vision, eye pressure, or a bulging appearance of the eye. Spinal dural fistulas can cause leg weakness, numbness, walking difficulty, or bladder and bowel changes because of congestion around the spinal cord.

Other possible symptoms include persistent headache, dizziness, visual disturbance, seizures, confusion, or weakness on one side of the body. Many symptoms are caused by venous congestion rather than a blockage in an artery. Importantly, symptom severity does not always show the degree of risk; imaging is needed to understand the anatomy and drainage pattern.

Causes and Risk Factors

In many people, the exact cause of a dural arteriovenous fistula is not known. These fistulas are usually considered acquired, meaning they develop over time rather than being present from birth. They may appear after changes in venous pressure or after a venous sinus becomes narrowed or blocked.

Possible associated factors include previous head injury, surgery, infection, inflammation, blood clotting in a venous sinus, or conditions that increase the tendency to form clots. Some dAVFs occur without any clear trigger. Age may play a role, as dAVFs are more often diagnosed in adults than in children, although they can occur at different stages of life.

The most important clinical feature is not simply why the fistula formed, but how it drains. When venous blood drains backward into cortical veins on the surface of the brain, called cortical venous reflux, pressure can rise in delicate veins. This pattern is associated with a higher risk of bleeding or neurological symptoms and usually leads doctors to recommend active treatment.

Diagnosis and Imaging

Diagnosis begins with a detailed medical history and neurological examination. The doctor may ask when the pulsatile tinnitus started, whether it is in one or both ears, what makes it better or worse, and whether there are eye symptoms, headaches, seizures, weakness, or balance problems. In some cases, a clinician may hear a bruit, an abnormal vascular sound, with a stethoscope near the skull, neck, or eye.

Imaging is essential because many conditions can cause pulsatile tinnitus. MRI of the brain can show signs of enlarged veins, venous congestion, swelling, or previous bleeding. MR angiography and CT angiography help evaluate arteries, veins, and venous sinuses. CT may also assess the temporal bone and middle ear region if ear-related causes are being considered.

Catheter cerebral angiography, also called digital subtraction angiography, is often the most detailed test for a suspected dAVF. During this procedure, a thin catheter is guided through a blood vessel, usually from the groin or wrist, and contrast dye is injected while X-ray images are taken. Angiography shows the feeding arteries, fistula site, venous drainage, and presence or absence of cortical venous reflux. This information guides treatment planning and helps determine the safest approach.

Treatment Options

Treatment is individualized. A low-risk dAVF without cortical venous reflux and with mild symptoms may sometimes be monitored with follow-up imaging and clinical review. However, a fistula with high-risk drainage, progressive symptoms, bleeding, seizures, or neurological changes is usually treated to disconnect the abnormal artery-to-vein pathway.

Endovascular treatment is often the first-line approach. A neurointerventional specialist guides a catheter through the blood vessels to the fistula and delivers materials that block the abnormal connection. These may include liquid embolic agents, coils, or other devices, depending on the anatomy. The approach may be transarterial, through feeding arteries, or transvenous, through the venous side. The goal is to close the fistula while preserving normal circulation.

If endovascular treatment is not suitable or does not fully close the fistula, microsurgery may be recommended. Surgery aims to disconnect the abnormal draining vein or fistula point. Stereotactic radiosurgery may be considered for selected dAVFs, especially when the fistula is difficult to reach by catheter or open surgery, but its effect develops gradually over time. The treatment team discusses the expected benefits, possible risks, and follow-up plan before any procedure.

Recovery and Follow-Up

Recovery after treatment depends on the type of procedure, the location of the fistula, and the symptoms present before treatment. After endovascular embolization, patients are usually monitored for a short period to check neurological status, the catheter access site, and blood pressure. Some people notice that pulsatile tinnitus improves quickly if the fistula has been completely closed, while other symptoms may take more time to settle.

Follow-up imaging is an important part of care. Doctors may recommend MRI, MR angiography, CT angiography, or repeat catheter angiography to confirm that the dAVF remains closed and that venous drainage has normalized. The timing depends on the initial risk pattern and treatment result.

Patients should follow their doctor’s instructions about activity, medications, wound care, and return to work or travel. If blood-thinning medication, pain control, or other treatments are prescribed, they should be used exactly as directed. New or worsening neurological symptoms after treatment should be reported promptly, even if the initial recovery has been smooth.

Prevention and Self-Care

There is no reliable way to prevent every dural arteriovenous fistula, because many cases develop without a clear cause. General vascular health remains important. Managing blood pressure, not smoking, staying physically active as advised, and seeking care for clotting disorders or significant head injuries can support overall brain and blood vessel health.

For people with pulsatile tinnitus, self-care should focus on safe symptom tracking rather than self-diagnosis. Keeping a note of when the sound occurs, whether it is one-sided, whether it changes with position, and whether it is associated with headache, visual symptoms, dizziness, or weakness can help the doctor. It is also helpful to list current medications, previous surgeries, trauma, infections, and any known clotting problems.

Patients should avoid repeatedly pressing on the neck to change the sound of tinnitus, as this can affect blood flow and does not treat the cause. They should also avoid delaying assessment if symptoms are persistent, one-sided, or pulse-synchronous. Many causes of pulsatile tinnitus are treatable, and timely evaluation helps direct care appropriately.

When to See a Doctor

A person should seek medical evaluation for new or persistent pulsatile tinnitus, especially if it is one-sided, matches the heartbeat, or is accompanied by headache, dizziness, vision changes, eye redness, double vision, or neurological symptoms. Non-urgent but timely assessment is also appropriate when pulsatile tinnitus affects sleep, concentration, or quality of life.

Immediate medical attention is needed for sudden weakness, numbness, difficulty speaking, severe sudden headache, seizure, loss of consciousness, new confusion, or sudden vision loss. These symptoms can have many causes, including stroke or bleeding, and require urgent assessment.

International patients can be evaluated at Acibadem International, where multidisciplinary specialists in neurology, neurosurgery, radiology, and neurointerventional care work within JCI-accredited hospitals to diagnose and treat conditions such as dural arteriovenous fistula. The most appropriate plan depends on imaging findings, symptoms, overall health, and the patient’s preferences after a detailed discussion with the care team.

Frequently asked questions

Is a dural arteriovenous fistula the same as a brain aneurysm?

No. A dural arteriovenous fistula is an abnormal connection between an artery and a vein in the dura, while an aneurysm is a bulging or weakened area of an artery wall. Both involve blood vessels and may require specialist imaging, but their causes, anatomy, and treatments are different.

Why does a dural arteriovenous fistula cause pulsatile tinnitus?

A dAVF can create fast, turbulent blood flow near the venous sinuses or structures close to the ear. This turbulence may be heard as a rhythmic whooshing sound that matches the heartbeat. Pulsatile tinnitus has several possible causes, so imaging is needed to confirm whether a dAVF is present.

What is the best imaging test for a suspected dAVF?

MRI, MR angiography, and CT angiography are often used first because they provide important noninvasive information. Catheter cerebral angiography is usually the most detailed test and is often required to map the fistula before treatment. The doctor selects imaging based on symptoms, examination findings, and previous test results.

Does every dural arteriovenous fistula need treatment?

Not always. Some low-risk fistulas without dangerous venous drainage may be monitored, especially if symptoms are mild. Fistulas with cortical venous reflux, bleeding, progressive neurological symptoms, or significant venous congestion usually require active treatment.

How is endovascular treatment performed?

Endovascular treatment is performed through a thin catheter guided inside the blood vessels under imaging. The specialist delivers embolic material, coils, or other devices to close the abnormal connection. The exact technique depends on the fistula’s location, feeding arteries, and venous drainage.

Can pulsatile tinnitus go away after treatment?

If the tinnitus is caused by the fistula and the abnormal blood flow is successfully closed, the sound may improve or disappear. Improvement can be immediate in some people, while others may notice gradual change. Follow-up imaging helps confirm whether the fistula has been fully treated.

Can a dural arteriovenous fistula come back?

Recurrence is possible, although many successfully treated fistulas remain closed. Follow-up visits and imaging are important to confirm the result and detect any persistent or recurrent abnormal flow. Patients should report the return of pulsatile tinnitus or new neurological symptoms to their doctor.

References

• National Institute of Neurological Disorders and Stroke
• American Heart Association/American Stroke Association
• Society of NeuroInterventional Surgery
• Radiological Society of North America
• American Association of Neurological Surgeons

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.