Definition

Hemifacial spasm (HS) causes muscles to contract on one side of the face. A person cannot control the spasm.

Causes

HS does not always have a cause. It may be due to:

• A blood vessel pressing on the facial nerve
• Facial nerve injury
• Tumor

Muscles of the Face Copyright © Nucleus Medical Media, Inc.

Risk Factors

HS is more common in older women. It is also more common in people who are Asian.

Symptoms

Problems may be:

• Twitching of the eyelid muscle that causes the eye to close
• A mouth that is pulled to one side
• Spasms of all the muscles on one side of the face

Diagnosis

The doctor will ask about your symptoms and health history. A physical exam will be done. It will focus on the face.

Images of the head may be taken. This can be done with:

• MRI scan
• CT scan
• Angiography

Nerve and muscle function may be tested. This can be done with electromyography (EMG).

Treatment

The goal of treatment is to ease pressure on the nerve. This can be done with:

• Injections of botulinum toxin to temporarily stop spasms
• Antiseizure medicine

Some people may need surgery to reposition a blood vessel that is pressing on a nerve.

Prevention

There are no known guidelines to prevent this problem.