Practice Essentials
Eyelid myokymia typically is benign, self-limited, and not associated with any disease. Intervention usually is unnecessary. Botulinum toxin injections are the treatment of choice when needed. Rarely, eyelid myokymia may occur as a precursor of hemifacial spasm, blepharospasm, Meige syndrome, spastic-paretic facial contracture, multiple sclerosis, autoimmune disease, and brainstem lesions (eg, pontine glioma). MRI with contrast to image the central and peripheral pathways of the facial nerve is warranted in rare cases. Medication-related eyelid myokymia rarely occurs with agents such as topiromate, clozepine, flunarizine, and gold salts. [1]
Background
Myokymia is characterized by spontaneous, fine fascicular contractions of muscle without muscular atrophy or weakness. Eyelid myokymia results from fascicular contractions of the orbicularis oculi muscle. Eyelid myokymia typically is unilateral, with the most common involvement being one of the lower eyelids. When multiple eyelids are involved, the fascicular contractions of each eyelid are independent of each other. The contractions are periodic and last seconds to hours.
In most cases, eyelid myokymia is benign, self-limited, and not associated with any disease. Intervention usually is unnecessary. Rarely, eyelid myokymia may occur as a precursor of hemifacial spasm, blepharospasm, Meige syndrome, spastic-paretic facial contracture, multiple sclerosis. autoimmune disease, and brainstem lesions (eg, pontine glioma). Medication related eyelid myokymia rarely occurs with agents such as topiromate, clozepine, flunarizine, and gold salts.
Pathophysiology
Consisting of involuntary fine undulating contractions across the striated muscle, the pathophysiology of eyelid myokymia is not well understood. The contractions are nonsynchronous semirhythmic discharges of motor units discharging at a rate of 3-8 Hz. The discharges have intervals of 100-200 ms between individual motor bursts. The contractions are transient and intermittent. The focus of irritation most likely is the nerve fibers within the muscle. Pontine dysfunction in the region of the facial nerve nucleus also has been suggested. Possible precipitating factors include stress, fatigue, and excessive caffeine or alcohol intake.
Epidemiology
Frequency
United States
The incidence and prevalence of eyelid myokymia are unknown, but symptoms of eyelid myokymia are frequently encountered in the ophthalmic clinic.
Mortality/Morbidity
Eyelid myokymia is a benign and self-limited condition in most patients, but, in some cases, it may be a precursor of hemifacial spasm, blepharospasm, Meige syndrome, spastic-paretic facial contracture, facial myokymia, multiple sclerosis. autoimmune disease, and brainstem lesions (eg, pontine glioma). Medication related eyelid myokymia rarely occurs with agents such as topiromate, clozepine, flunarizine, and gold salts.
Age
Eyelid myokymia usually occurs in adults and may occur at any age.
Prognosis
Prognosis is excellent in most cases. Recurrences are relatively common with a wide range of frequency among individuals.
