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Long-Term Corneal Endothelial Parameters of COVID-19 Patients With Ocular Surface Symptoms
Oğuzhan Kılıçarslan1, Aslıhan Yılmaz Çebi2, Cezmi Doğan3
1Department of Ophthalmology, Ayancık State Hospital, Sinop, Turkey.
Purpose:
This study aimed to investigate the long-term effects of COVID-19 on corneal endothelial cell morphology in patients with ocular symptoms to assess possible corneal involvement in patients who recovered.
Methods:
The COVID-19 group included patients diagnosed and treated at Istanbul University Cerrahpasa Medical Faculty with confirmed SARS-CoV-2 infection and ocular irritation symptoms. The control group was comprised of age- and sex-matched individuals. The controls had no ocular pathologies. Noncontact specular microscopy (Konan Cell Check SL, Hyogo, Japan) was performed using the center method after 156 ± 16 days of COVID-19 diagnosis. Parameters such as endothelial cell density (ECD), hexagonality (HEX), coefficient of variation, and central corneal thickness were analyzed.
Results:
Specular microscopy results of 54 COVID-19 patients with ocular irritation symptoms and 72 controls were evaluated. Ocular symptoms in COVID-19 patients included conjunctival hyperemia, foreign body sensation, tearing, ocular secretion, and chemosis. Mean (±SD) ECD was 2770 ± 31 (cells/mm 2 ) in the COVID-19 group and 2897 ± 26 in the control group, and mean (±SD) HEX was 46.52 ± 6.38 in the COVID-19 group and 58.22 ± 13.94 in the control group. COVID-19 patients exhibited significantly lower endothelial ECD and HEX levels than controls ( P = 0.003 and P < 0.001, respectively). Coefficient of variation and central corneal thickness analyses did not reach statistical significance.
Conclusions:
COVID-19 can cause long-term alterations in the corneal endothelial cells, leading to decreased ECD and HEX. Future research should focus on the long-term implications of COVID-19 on the corneal health and visual outcomes.
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