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Long-Term Corneal Nerve and Ocular Surface Findings After COVID-19 Requiring Hospitalisation: An Observational
Andreas Guttmann1, Nora Woltsche1, Astrid Heidinger1
1Department of Ophthalmology, Medical University of Graz, Graz, Austria.
Purpose:
Persistent ocular symptoms have been reported after COVID-19, but their relationship to ocular surface findings and corneal nerve morphology after hospitalization remains unclear. Therefore we evaluated long-term ocular surface and corneal nerve findings after SARS-CoV-2 infection in previously hospitalised patients.
Methods:
In this observational study, 26 patients from a cohort of reverse transcriptase-PCR-confirmed COVID-19 cases hospitalised during the first pandemic wave underwent one ophthalmic examination after a median follow-up of 2.77 years (1.67-3.86 years). Based on follow-up symptoms, patients were classified as the post-COVID ocular symptom group (P-COSG, n = 16) or the COVID-19 recovered without ocular symptoms group (CRWOS, n = 10). Examinations included symptom questionnaires, tear film and ocular surface assessment, meibography, corneal sensitivity testing, and in vivo confocal microscopy (IVCM) to assess corneal sub-basal nerve morphology.
Results:
Among the analysed follow-up participants, persistent ocular symptoms were present in 92.3% (12/13) of initially symptomatic patients, whereas 30.8% (4/13) of initially asymptomatic patients developed new symptoms. Symptom burden was significantly higher in P-COSG than in CRWOS, with higher Ocular Surface Disease Index scores (41.5 ± 17.7 vs 21.8 ± 11.3; p = 0.005) and FACE scores (4.25 ± 1.13 vs 2.00 ± 2.00; p = 0.001). Objective tear film, ocular surface, and IVCM-derived corneal nerve parameters did not differ significantly between groups. Dendritic cells were detected in 100% of P-COSG and 90% of CRWOS patients, and microneuromas in 62.5% and 50.0%, respectively. In P-COSG, older age was associated with lower corneal nerve fibre density and length. Symptoms were not relieved by topical oxybuprocaine in 43.8% of symptomatic participants.
Conclusions:
Ocular symptoms may persist or emerge years after COVID-19 without significant differences in measured tear film and ocular surface findings between symptom groups. This symptom-sign discordance is compatible with a possible neuropathic or neuroinflammatory component.
