Common ocular complications/ manifestations of COVID-19 include dry eye, non-specific conjunctivitis, and retinal vascular changes. The exact incidence of these complications is yet to be determined. However, ocular surface disorders including conjunctivitis and dry eye are most frequently reported in COVID-19 patients.[5,9,10,3] Non-specific conjunctivitis, including conjunctival hyperemia, lacrimation, follicular conjunctivitis, ocular pain have been reported in 5 to 31% of patients.[11-14] While ocular surface diseases ranging from conjunctivitis to keratopathy was seen in up to 60% of critically ill patients.[15,16] Other relatively common ocular manifestations of SARS-CoV-2 include keratoconjunctivitis, epithelial defects subepithelial infiltrates and pseudodendrites.[17,18,10]
Granulomatous anterior uveitis, retinal detachment, retinal vasculitis, retinitis, and retinal degenerations are seen in animal studies.[4,5,10] In a study of 54 COVID-19 patients, dilatation of retinal veins and vascular tortuosity were most common and seen in 27.7% and 12.9% of patients. Other changes included retinal hemorrhages in 9.25% and cotton wool spots in 7.4% of patients.[17] Another study reported hyperreflective foci in the macula of 12 COVID-19 patients using optical coherence tomography. Besides OCT findings, 4 patients had cotton wool spots and retinal microhemorrhages.[18] Concerns about the potential misinterpretation of these results have recently been posed, signifying that hyperreflective areas could merely represent normal retinal vessels.[19,20] Retinal vein occlusion and valsalva retinopathy are rare potential associations of COVID-19.[11] Neuroophthalmological associations of SARS-CoV-2 are rare. A limited number of case reports have described Miller Fisher syndrome, Guillain-Barré syndrome, polyneuritis cranialis, internuclear ophthalmoparesis and oculomotor palsy.[5] Meningitis, encephalomyelitis and encephalopathy may also affect these patients.[10,21]
The primary outcome of the present study was to evaluate the pattern of eyelid myokymia presumably associated with COVID-19 and to the best of our knowledge, it is the first study to reporting eyelid myokymia as a potential association of SARS-CoV-2 infection. We included all patients who experienced lid twitching during or after recovery from covid-19 infection.
The frequency/rate of myokymia gradually declined over time to total resolution and most patients completely recovered within two months of recovery from systemic disease. Older age and longer hospital stay were associated with prolongation of lid myokymia while the history of conjunctivitis had no impact on the time for recovery of myokymia.
Eyelid myokymia results from doublets or triplets of spontaneous non-synchronous discharges of adjacent motor units at a 30 to 70 Hz rate with inter-discharge intervals of 100-200 ms.[8,22] It is most common of all facial myokymias, typically unilateral with a tendency for lower lid and limited to orbicularis oculi muscle. It is a self-limiting benign condition affecting otherwise healthy individuals at any age and resolves completely over days to months.[23,8,6] Nonetheless stress, anxiety, excessive caffeine intake and administration of topiramate are known associations.[24,7,8] Rarely it may be associated with Guillain‐Barre syndrome and multiple sclerosis.[25,26] Mental illness including anxiety and depression are common, affecting roughly 1/4th to half of the COVID-19 survivors, immediate post-recovery and may persist for long. The incidence of mental illness was greater in hospitalized patients.[27,28,1,29,30] None of our patients had a recent history of topiramate intake or heavy caffeine consumption. Nonetheless, eyelid myokymia in our cohort of patients is attributable to anxiety or presumably it is a manifestation of SARS-CoV-2 infection itself. Akin to classic eyelid myokymia, there was a gradual recovery of myokymia in our patients. While older age and hospitalization were associated with slower resolution of the disease.