Hemifacial spasm clinical features

This disease takes two forms: typical and atypical. In typical form, the twitching usually starts in the lower eyelid in orbicularis oculi muscle. As time progresses, it spreads to the whole lid, then to the orbicularis oris muscle around the lips, and buccinator muscle in the cheekbone area.

The reverse process of twitching occurs in atypical hemifacial spasm; twitching starts in orbicularis oris muscle around the lips, and buccinator muscle in the cheekbone area in the lower face, then progresses up to the orbicularis oculi muscle in the eyelid as time progresses.

The most common form is the typical form, and atypical form is only seen in about 2–3% of patients with hemifacial spasm.

Hemifacial spasm (HFS) is a condition of intermittent, painless, involuntary, spasmodic contractions of muscles innervated by the facial nerve in one side of the face only. May be limited to the upper or lower half of the face only, and excess lacrimation may be present. HFS usually begins with rare contractions of the orbicularis oculi, and slowly progresses to involve the entire half of the face and increases in frequency until the ability to see out of the affected eye is impaired.

HFS may be associated with trigeminal neuralgia, geniculate neuralgia; see Tic convulsif or vestibular and/or cochlear nerve dysfunction.

HFS is more common in women, is seen more often on the left, and usually presents after the teenage years. Auditory function testing reveals abnormal acoustic middle ear reflex in almost half of patients, indicating some degree of VIII compromise.

Meige’s syndrome: hemifacial spasm with oral movements.

▶ Note. HFS and palatal myoclonus are the only involuntary movement disorders that persist during sleep.

Non-pulsatile tinnitus, stapedial muscle spasms: as occurs in hemifacial spasm