by Amy Scholten, MPH
Vertebrobasilar insufficiency is poor blood flow to the back of the brain. This is due to damaged blood vessels (arteries). Blood flow to the back of the brain is supplied by two arteries of the neck. These two arteries join to form the basilar artery.
A decrease in blood flow can damage the brain and impair normal function.
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. Plaque is a fatty substance in the blood.
Plaque buildup makes it hard for blood to flow through the blood vessels. In time, it can completely block the artery.
The blood vessels may also be damaged due to a birth defect.
Things that can raise the risk of vertebrovascular insufficiency are:
Symptoms may include:
The doctor will ask about symptoms and health history. A blood flow problem in the brain may be suspected based on symptoms.
Tests are done 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. This can help the doctor see how much of the blood vessel is blocked. An MRI scan may also be done to see if a stroke has happened.
The goal of treatment is to reduce further damage to the blood vessels. It is also to decrease the risk of stroke. Options include:
Improving Heart Health
If the condition and symptoms are not severe, the doctor may advise:
More severe blockage or damage may require a procedure such as:
Heart healthy habits can help keep blood vessels healthy. They include:
American Heart Association
National Stroke Association
Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada
Lima Neto AC, Bittar R, et al. Pathophysiology and diagnosis of vertebrobasilar insufficiency: a review of the literature. Int Arch Otorhinolaryngol. 2017;21(3):302-307.
Vertebral artery stenosis and occlusion. EBSCO Dynamed website. Available at: https://www.dynamed.com/condition/vertebral-artery-stenosis-and-occlusion. Accessed July 19, 2021.
Vertebro basilar insufficiency. Nebraska Medicine website. Available at: https://www.nebraskamed.com/neurosurgery/vertebral-basilar-insufficiency. Accessed July 19, 2021.
Vertebrobasilar insufficiency. UC Davis Health System website. Available at:
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Accessed July 19, 2021.
Last reviewed July 2021 by EBSCO Medical Review Board Michael J. Fucci, DO, FACC
Last Updated: 7/19/2021