What Is Transient Vertebrobasilar Insufficiency?

Transient vertebrobasilar insufficiency (TVI) may not be a term you hear very often, but it’s related to one well-known condition: stroke.

TVI refers to the temporary inability of the vertebrobasilar arteries to supply enough blood to the brain. Specifically, the vertebrobasilar arteries supply blood to the back of the brain, cerebellum and brainstem. These parts of the brain govern functions such as breathing, sleeping, balance and motor coordination.

TVI is most often caused by atherosclerosis, or the buildup of plaque in the arteries. Arterial plaque may develop due to numerous factors:

• Age and sex (men and older people have higher risk)
• High blood sugar
• Family history
• High blood pressure
• High levels of low-density lipoprotein cholesterol in the blood
• Smoking

Rare Causes of TVI

Bending or rotating the neck sharply has been known to cause TVI. Also known as bowhunter’s syndrome (side-to-side rotation) or beauty parlor syndrome (tipped backward), TVI happens when an acute twisting movement of the neck limits blood flow in the vertebrobasilar arteries. In some cases, an artery may even be torn.

What Are the Symptoms of TVI?

People with TVI may not have symptoms at first. Later, they may become symptomatic, and eventually TVI can lead to stroke. About 25% of strokes originate from the vertebrobasilar arteries. A doctor may make a diagnosis when there are symptoms such as:

• Dizziness, vertigo and fainting
• Drop attacks (falls due to sudden weakness, when consciousness isn’t lost)
• Headaches
• Hearing problems, including hearing loss and tinnitus
• Vision problems, including double vision, seeing things that aren’t there and blindness
• Vomiting
• Weakness in arms or legs

Diagnosing TVI

It’s important to get a correct diagnosis right away. A doctor will first perform a physical exam, take blood work and get a full history (detailed narrative about symptoms). TVI may be confused with a balance disorder, such as inner ear disease, so the doctor may do differential testing or perform a stroke risk assessment to help understand the condition.

If TVI is suspected, the doctor will order tests, such as ultrasound, CT angiography or magnetic resonance angiography, to help identify places where arteries have blockage or damage.

TVI Treatments

Medical and noninvasive endoscopic treatments are available for TVI. Medical options include anticoagulant medications to prevent blood clots. If there are stroke risk factors such as diabetes, high blood pressure or high cholesterol, a doctor may prescribe medicine to manage them, too.

The doctor may also recommend angioplasty and stenting. In this procedure, the doctor threads a fine tube through the arm or groin up to the blocked artery. Then, he or she inflates a small balloon to compress blockage and places a stent to prevent the artery from collapsing.