Which statement about myokymia is NOT true?

Which statement about myokymia is NOT true?

• A. It is characterized by unilateral eyelid twitching
• B. It commonly affects the orbicularis oculi only
• C. It is commonly caused by stress
• D. It is characterized by unilateral eyelid forced closure

Answer: (D)

Myokymia presents as fine, quivering movements of the eyelid due to spontaneous activity of the orbicularis oculi. It is usually unilateral and can be triggered or worsened by stress, fatigue, caffeine, or irritation. It does not cause the eyelid to close forcibly; that pattern is characteristic of blepharospasm, a dystonia that leads to involuntary, sustained eyelid closure and is often bilateral. Because myokymia produces twitching rather than forced closure, the statement describing unilateral eyelid forced closure is not true. The other statements fit: it commonly affects the orbicularis oculi, and stress is a common trigger.

Myokymia presents as fine, quivering movements of the eyelid due to spontaneous activity of the orbicularis oculi. It is usually unilateral and can be triggered or worsened by stress, fatigue, caffeine, or irritation. It does not cause the eyelid to close forcibly; that pattern is characteristic of blepharospasm, a dystonia that leads to involuntary, sustained eyelid closure and is often bilateral. Because myokymia produces twitching rather than forced closure, the statement describing unilateral eyelid forced closure is not true. The other statements fit: it commonly affects the orbicularis oculi, and stress is a common trigger.