Hemifacial spasm is an involuntary movement disorder characterized by contractions of the muscles of the face on only one side. Twitching of the muscles may start around the eye and progress over time to involve the corner of the mouth and possibly neck muscles. Spasms of the face may occasionally be associated with pain and can limit facial expression. Due to more persistent contraction, vision may be impaired. The most common cause of hemifacial spasm is compression of the facial nerve by a blood vessel.
Treatment for hemifacial spasm includes medications that are anticonvulsants (Phenytoin, Carbamazepine). Other medications that could be tried include Baclofen. These medications may be prescribed to block nerve impulses that give rise to the spasms.
Botox injections are an effective treatment for hemifacial spasm where injections are given to muscles of the face to reduce contraction. The effect of treatment is typically for 3 months after which repeat injections are administered.
If medications or Botox does not control the symptoms of hemifacial spasm, a surgical procedure known as a microvascular decompression may be considered. A MRI of the brain is required to demonstrate compression of the facial nerve by a blood vessel prior to surgical consideration.