Dural Arteriovenous Fistula: Symptoms, Causes, Diagnosis and Treatment

Written by Medicover Team and Medically Reviewed by Dr Krishna Haskar Dhanyamraju , Neurologists

Causes
Find a Doctor
Diagnosis
Treatment
FAQs
Book an Appointment

1. Causes 2. Find a Doctor 3. Diagnosis 4. Treatment 5. FAQs

Dural Arteriovenous Fistula (DAVF) is a rare vascular disorder characterized by an abnormal connection between arteries and veins within the dura mater, the outer covering of the brain or spinal cord. This abnormal blood flow can increase pressure in the veins and lead to symptoms such as headaches, pulsatile tinnitus, vision changes, seizures, or neurological deficits. Early diagnosis and appropriate treatment are essential to reduce the risk of bleeding, stroke, and other serious complications.

Are There Different Types of Dural Arteriovenous Fistulas?

Yes, dural arteriovenous fistulas (DAVFs) are grouped into types based on how and where the abnormal blood flow travels. These types help doctors understand the risk and decide how to treat them.

Borden Classification (Simple 3-Type System)

Type I: Blood flows normally into a nearby vein or sinus. This type is usually low-risk and might not need immediate treatment.
Type II: Some blood flows backward into small brain veins. This can increase pressure and may lead to bleeding or swelling.
Type III: All blood drains directly into brain veins without using the larger sinus. This type is the most dangerous and needs quick treatment.

Cognard Classification (More Detailed System)

This system looks at the same thing, where the blood goes, but breaks it down into more steps.

Type I: Normal drainage. Usually harmless.
Type IIa: Some blood goes the wrong way in large veins.
Type IIb: Blood flows back into brain veins.
Type IIa+b: A mix of the two above.
Type III IV: Blood drains only into brain veins and may cause bulging or weak spots. These types have a higher risk of bleeding.
Type V: The abnormal blood drains toward the spine. This may affect the spinal cord.

What are the Symptoms of Dural Arteriovenous Fistula?

A dural arteriovenous fistula (DAVF) can cause different symptoms depending on where it forms and how much pressure it puts on nearby veins. Some people may not notice anything at first, while others may have clear warning signs.

Early Symptoms Include

Frequent or throbbing headaches
A pulsing sound in one ear (pulsatile tinnitus)
Blurry or double vision
Red or swollen eyes
Sudden numbness or weakness, often on one side
Signs of a stroke, like confusion or a drooping face

What Causes a Dural Arteriovenous Fistula and Whos at Risk?

A dural arteriovenous fistula (DAVF) happens when a blood vessel connects abnormally inside the brain's outer covering, called the dura mater. These connections can form suddenly or over time. While doctors don't always know why they occur, several possible causes and risk factors have been identified.

Possible Causes

Head Injury: Trauma to the skull or brain can damage blood vessels and lead to abnormal connections.
Blood Clots in Brain Veins: Clots can block blood flow, forcing nearby vessels to reroute and form a fistula.
Brain or Spine Surgery: Some DAVFs develop after procedures involving the brain or spinal cord.
Infections: Serious infections in or around the brain can change how blood vessels behave.
Increased Pressure in Brain Veins: If blood can't drain properly, pressure builds up, and this may trigger abnormal vessel growth.

Risk Factors

Age (Usually Over 50): DAVFs are more common in older adults.
High Blood Pressure: Long-term high blood pressure can damage blood vessels and increase the risk.
Blood Clotting Problems: Conditions that affect how your blood clots may also affect how veins drain.
Smoking and Alcohol Use: These habits can harm blood vessels over time.
Hormonal Changes (Rare): In a few cases, pregnancy or hormonal shifts may play a role.

When to See a Doctor for Dural Arteriovenous Fistula?

Individuals with persistent pulsatile tinnitus, unexplained headaches, vision changes, or neurological symptoms should consult a Neurologist or Neurosurgeon promptly for evaluation.

You should see a doctor if you experience:

Persistent whooshing sound in one ear
Unexplained headaches or vision problems
Weakness, numbness, or balance problems

Seek immediate medical attention if you:

Develop sudden severe headache
Experience seizures, loss of consciousness, or stroke-like symptoms
Notice sudden weakness, difficulty speaking, or vision loss

These symptoms may indicate intracranial bleeding or other serious neurological complications requiring emergency treatment.

Find Neurologists for Dural Arteriovenous Fistula Treatment Near You

How is Dural Arteriovenous Fistula Diagnosed?

Diagnosing a dural arteriovenous fistula (DAVF) isn't always simple. The symptoms can look like other brain or nerve problems, so clear and accurate testing is important. Doctors use a few imaging tests to spot where the abnormal connection is and how serious it may be.

Tests You Might Need

MRI (Magnetic Resonance Imaging): This scan gives a detailed view of the brain. It can show if there's unusual blood flow or pressure.
MRA (Magnetic Resonance Angiography): This looks closely at the brain's blood vessels and helps spot abnormal connections.
CT Scan or CT Angiography (CTA): These are useful in emergencies to check for bleeding or swollen veins in the brain.
Digital Subtraction Angiography (DSA): This is the most accurate test for DAVFs. It shows real-time images of blood flow and helps doctors plan treatment.

How is a Dural Arteriovenous Fistula Treated?

The treatment for a dural arteriovenous fistula (DAVF) depends on its location, size, and how much it affects blood flow in the brain. Some DAVFs don't need immediate care, while others require quick treatment to prevent serious problems like bleeding or stroke.

Endovascular Embolization

This is a minimally invasive procedure. A thin tube is guided through the blood vessels to the fistula, and a special material is used to block the abnormal connection.

Hospital Stay: Usually 1 to 2 days
Recovery: Most people return to daily routines within 1to 2 weeks

Microsurgery

In some cases, surgery is needed to close off the fistula. The surgeon carefully disconnects the abnormal vessel through a small opening in the skull.

Hospital Stay: 3 to 5 days
Recovery: Light activity in 2 weeks, full recovery in about a month

Stereotactic Radiosurgery (Gamma Knife or CyberKnife)

This method uses focused radiation to close the fistula over time. Its painless and done without cuts.

Hospital Stay: Usually not required
Recovery: You can go home the same day, but it may take months for the fistula to fully close

Your health is everything - prioritize your well-being today.

Consult Dural Arteriovenous Fistula Doctors Today

What is the Recovery Process for Dural Arteriovenous Fistula?

Recovery depends on the size and location of the fistula, the treatment performed, and whether neurological complications occurred before treatment. Many individuals recover well after successful closure of the fistula, while those with brain hemorrhage or stroke may require rehabilitation. Regular follow-up imaging is important to confirm complete closure and detect recurrence.

Following medical advice, attending scheduled follow-up appointments, and participating in rehabilitation when needed help optimize neurological recovery and long-term health.

Recovery Includes

Attending regular follow-up visits with a neurologist or neurosurgeon.
Undergoing repeat angiography or MRI as recommended.
Taking prescribed medications as directed.
Participating in physical, occupational, or speech therapy if needed.
Managing blood pressure and other vascular risk factors.
Seeking immediate medical attention if new neurological symptoms develop.

Frequently Asked Questions

1. How is a Dural Arteriovenous Fistula treated?

Treatment may include endovascular embolization, microsurgical removal, stereotactic radiosurgery, or a combination of these approaches depending on the fistula's characteristics.

2. Can a Dural Arteriovenous Fistula cause a stroke?

Yes, certain DAVFs increase the risk of stroke or brain hemorrhage due to abnormal blood flow and increased pressure in the brain's veins.

3. What complications can occur with a Dural Arteriovenous Fistula?

Complications may include intracranial hemorrhage, seizures, neurological deficits, vision loss, cognitive impairment, and increased intracranial pressure.

4. Can a Dural Arteriovenous Fistula recur after treatment?

Although recurrence is uncommon, it can occur in some cases. Regular follow-up imaging is important to confirm successful treatment and detect recurrence.

5. What is the prognosis for a Dural Arteriovenous Fistula?

The prognosis is generally good when diagnosed early and treated appropriately. Outcomes depend on the size, location, and severity of the fistula.

6. Who is at risk of developing a Dural Arteriovenous Fistula?

Adults with a history of head trauma, venous sinus thrombosis, brain surgery, or certain vascular disorders may have a higher risk of developing a DAVF.