‌Hemifacial spasm is a disorder of the nerves and muscles that causes nonpainful involuntary twitching on one side of the face. Many people refer to hemifacial spasms as lip muscle spasms. Hemifacial ...

Hemifacial spasms happen when the muscles on either the left or right side of your face twitch without warning. This is caused by damage or irritation to the facial nerve, also known as the seventh ...