What is Myokymia?
Ocular myokymia is a series of spontaneous, gentle, constant, rippling contractions that spread through the affected striated muscle. Eyelid myokymia is the most common type of facial myokymia with the orbicularis oculi being the most affected muscle. Chronic, isolated eyelid myokymia is a benign condition and is not associated with any other neurologic disease. Eyelid myokymia can spread to additional muscles on one or both sides of the face referred to as facial myokymia.
- Ocular myokymia is a contraction of the orbicularis oculi.
- Stress, caffeine, and fatigue are thought to be factors.
- No treatment is needed, contractions are self-limited.
Myokymia is likely to be unilateral and affects the lower eyelid more frequently than the upper eyelid. The contractions are self-limited, periodic, and last seconds to hours. In rare cases, upper and lower eyelids involvement can occur on the same side and at the same time.
Factors that Cause Myokymia
The exact cause of ocular myokymia is unknown, but there are some associated factors including stress, fatigue, and caffeine intake. Female gender and cold weather are risk factors for chronic eyelid myokymia. It tends to affect healthy young subjects. Medication-induced myokymia is uncommon, but medications like topiramate, clozapine, gold salts, and flunarizine can trigger eyelid myokymia.
Facial myokymia can be caused by damage to the facial nerve nucleus in the pons of the brain from demyelinating diseases, such as multiple sclerosis or compression from brainstem tumors. Rarely, persistent eyelid myokymia has been reported as a presenting sign of multiple sclerosis or a brainstem tumor.
Superior oblique myokymia is an uncommon condition often misdiagnosed. Presentation includes double vision and a “jumping image.” It typically affects one eye of young adults. There is no known cause, but may also be associated with multiple sclerosis, trauma or tumor involving the pons.
- Twitching of the upper or lower eyelid
- Twitching of the face
Fine contractions of the orbicularis oculi muscle may be noticeable during an eye exam. Routine neuroimaging studies for patients with chronic myokymia are unnecessary because of their low yield findings. Facial myokymia may need neuroimaging if the cause is unknown.
There is no way to stop or “fix” short-term myokymia. Conservative management includes rest, reassurance, and decreased caffeine consumption.
In the case of myokymia persisting for more than three months, botulinum toxin injections are successful as first-line treatment.
If the cause of facial myokymia is multiple sclerosis, it often improves on its own after days or weeks. If due to a brain tumor, it may persist. Both of these conditions require multidisciplinary care.