Hemifacial spasm (HFS) is a movement disorder most commonly caused by vascular compression of the VII cranial nerve at its root exit zone from the brainstem. It manifests as involuntary contractions and twitching on ipsilateral side of the face.
Also indexed as
Bell spasmClonic hemifacial spasmHemifacial spasmfacial spasm NECmyoclonus facial spasm