Hemifacial spasm (HFS) is a rare movement disorder that causes involuntary muscle contractions on one side of the face. It typically starts with painless but annoying twitching around one eye.

Hemifacial spasm (HFS) is a neurological disorder manifested by twitching on one side of the ... Most cases of HFS do not have an obvious cause and are referred to as “idiopathic”. However, HFS is ...

Bell’s palsy can cause twitching and weakness on one side of the face. Researchers believe Bell’s palsy and certain infections may be linked. These can include: Hemifacial spasms, also known ...