Hemifacial spasm is a neuromuscular disorder characterized by frequent involuntary contractions (spasms) of muscles on one side of the face. It may be caused by an injury, a tumor, or a blood vessel compressing the facial nerve. In some cases, no cause can be found.
How common is hemifacial spasm?
Hemifacial spasm is rare. The prevalence has been estimated to be eight per 100,000 in men and 15 per 100,000 in women.
Who gets hemifacial spasm?
Hemifacial spasm occurs in both men and women, but it more frequently affects middle-aged or elderly women. It is more common among the Asian population.
How is hemifacial spasm diagnosed?
Your doctor may do the following tests to diagnose hemifacial spasm:
- Neurological examination
- Electromyography (EMG)
- Nerve conduction studies
In most cases, the first symptom of hemifacial spasm is intermittent twitching of the eyelid muscle. Gradually, other muscles of the lower face can become involved.
Eventually, all muscles on one side of the face are affected. The twitching is not associated with pain.
Treatment for hemifacial spasm may include the following:
- Botox injections into the affected area
- Surgery to relieve nerve compression (microvascular decompression)
- Surgery to relieve other underlying causes (tumors, for example)
- Medications, such as anticonvulsants or muscle relaxants
- Date of last review: December 16, 2016
- Author: Kamala Saha, MD