Twitches & Hemifacial Spasm
Twitches & Hemifacial Spasm
Twitches
- Twitches are involuntary muscle spasms that are NOT suppressible or able to be volitionally initiated and there is no compulsion to generate the movement.
Hemifacial Spasm
- Unilateral repetitive, paroxysmal, uncontrollable spasmodic contractions of facial nerve innervated musculature: there is a unilateral spasmodic twitch of the eyelid, along with a facial grimace (twitch of the side of the face).
- It most commonly secondary to neurovascular compression of the facial nerve; hence microvascular decompression is sometimes done to prevent the twitching.
- It typically starts in the orbicularis oculi and then propagates via ephaptic transmission: the impulse passes between facial nerve branches.