Vertebrobasilar Insufficiency


Vertebrobasilar insufficiency is poor blood flow to the back of the brain because of damage to blood vessels. Blood flow to the back of the brain is supplied by 2 arteries of the neck. These 2 arteries join to form the basilar artery.

Brain tissue requires a regular flow of blood to supply nutrients and oxygen. A decrease in blood flow can cause damage to brain tissue and impair normal function. The area of the brain affected by the basilar artery affects the regulation of consciousness, breathing, heart rate, coordination, balance and vision.


Vertebrobasilar insufficiency is caused by a narrowing or damage of the arteries. The most common cause is atherosclerosis, a build-up of plaque in blood vessels. This plaque is a combination of fatty substances in the blood, buildup of tissue from injures to the blood vessels walls, and sticky blood cells called platelets.

The plaque makes the pathway for the blood to flow through smaller. It can eventually lead to a complete blockage of the artery. Plaque also makes the blood vessel stiff and less able to adjust to changes in blood flow.

The blood vessels may also be damaged due to congenital defect.

Risk Factors

There are no factors related specifically to vertebrobasilar insufficiency. Factors that increase the risk of atherosclerosis in any blood vessel include:

Current heart disease, peripheral artery disease, or atherosclerosis anywhere else in the body increases the risk for vertebrobasilar insufficiency.


Symptoms may include:

  • Vision problems such as loss of vision or double vision
  • Headache
  • Lightheadedness
  • Vertigo —sensation of the spinning while standing still
  • Loss of coordination
  • Numbness or tingling especially in arms
  • Nausea or vomiting
  • Speech difficulty such as slurred speech
  • Sudden generalized weakness—called drop attacks

Many of these symptoms are similar to those of a stroke. If you or someone you know has any of these symptoms, call for emergency medical services right away.


You will be asked about your symptoms and medical history. A blood flow problem in the brain may be suspected based on symptoms.

To confirm the diagnosis images of the blood vessels in the brain may be taken with:

An x-ray angiography may be done if the imaging tests are not clear. The angiography can help determine the degree of blockage. An MRI scan may also be done to see if a stroke has occurred.

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Treatment is focused on reducing further damage to the blood vessels and decreasing the risk of stroke. Options include:

Improving Cardiovascular Health

Lifestyle changes and medical treatment may be recommended if the narrowing of the arteries and symptoms are not severe.

Medication may help manage factors that can worsen symptoms and increase the risk of complications. Prescribed medication may help to:

  • Lower blood pressure
  • Lower cholesterol
  • Decrease the blood's ability to form clots, which can decrease the risk of stroke

Quitting smoking is one of the most important lifestyle changes for vertebrobasilar insufficiency. Smoking causes irritation and damage to the blood vessels and increases the risk of stroke. Other lifestyle habits like healthy diet and regular exercise are also strongly recommended.

Surgical Options

More severe blockage or damage may require a procedure to help open the blood vessels.

Endovascular repair is the most common approach. It includes angioplasty and/or stents. Angioplasty places a balloon at the site of the blockage. The balloon is quickly inflated and deflated to help widen the blood vessel. Stenting places a wire or mesh device in the blood vessel that help prop open the blood vessel. The stent may also have medication to help keep the vessel clear of blood clots. Both stenting and angioplasty are done by passing a catheter through blood vessels in the arms or legs and passing it up to the brain.

Open surgery may also be done. These types of surgeries are used less often because of the risk of complications. Some open options include:

  • Endarterectomy —Removes plaque build-up on the inside of the blood vessel.
  • Bypass—A healthy section of blood vessel is removed from another area of the body. The healthy blood vessel is attached above and below the blockage in the vertebral artery. Blood can then flow through the bypass to maintain proper blood flow.


Heart healthy habits will help keep blood vessels throughout your body in good shape. Lifestyle habits that can help include:

  • Regular exercise.
  • Eating more fruits, vegetables, and whole grains. Limit dietary salt and fat.
  • Quitting smoking—Talk to your doctor about the best ways to quit.
  • Increasing your consumption of fish.
  • Drinking alcohol only in moderation. This means 1-2 drinks per day.
  • Maintaining a healthy weight.
  • Checking your blood pressure frequently. Follow your doctor's recommendations for keeping it in a safe range.
  • Keeping chronic medical conditions under control. This includes high cholesterol and diabetes.
  • Talking to your doctor about rehabilitation programs for alcohol use disorder or drug abuse.


American Heart Association
National Stroke Association


Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada


Vertebral artery stenosis and occlusion. EBSCO Dynamed Plus website. Available at: http://www.dynamed... . Updated June 8, 2015. Accessed March 1, 2018.
Vertebro basilar insufficiency. Nebraska Medicine website. Available at: Accessed March 1, 2018.
Vertebrobasilar insufficiency. UC Davis Health System website. Available at:
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Accessed March 1, 2018.
Last reviewed March 2018 by EBSCO Medical Review Board Michael J. Fucci, DO, FACC
Last Updated: 3/1/2016

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