Assessment of retinal vessels and corneal endothelium alterations in acute and post-COVID-19
https://doi.org/10.21516/2072-0076-2025-18-4-57-61
Abstract
The COVID-19 pandemic, caused by SARS-CoV-2, has shown significant systemic effects beyond the respiratory system, including ophthalmologic complications.
The purpose of the study is to assess alterations in retinal vessels and corneal endothelium in patients with acute and post-COVID-19 infection.
Material and methods. A prospective observational study was conducted at Al-Hussain Teaching Hospital in Iraq at two years 2021–2022, including 50 adult patients (56 % male) aged 61.7 ± 12.5 years with confirmed COVID-19 by PCR testing. Common comorbidities included hypertension (30 %), smoking (26 %), and diabetes mellitus (16 %). Comprehensive ophthalmologic examinations were performed, including retinal imaging and specular microscopy. Clinical and laboratory data were collected and analyzed using SPSS version 26.0.
Results. Significant laboratory changes were observed between acute and post-acute phases, indicating an inflammatory response during acute infection. Retinal alterations improved significantly post-acute COVID-19, with reductions in retinal hemorrhage, vessels tortuosity, and veins dilatation. Specular microscopy showed improvements in cell density, average cell area, coefficient of variation, and hexagonality.
Conclusion. COVID-19 has significant impacts on retinal and corneal health, with notable improvements post-infection. These findings highlight the need for on-going ophthalmologic monitoring in COVID-19 patients to manage and mitigate long-term ocular complications.
About the Authors
M. H. JaazIraq
Muataz Hasan Jaaz — M.B.CH.B, F.I.C.M.S., surgeon and lecturer of ophthalmology, department of surgery
Thi-Qar, 64001
A. A. Fahad
Iraq
Ammar Adil Fahad — optometrist, teaching staff, department of optics
Nile Street, Thi-Qar, 64001
References
1. Zhou P, Yang XL, Wang XG, et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature. 2020; 579 (7798): 270–3. doi: 10.1038/s41586-020-2951-z
2. Seah I, Agrawal R. Can the Coronavirus disease 2019 (COVID-19) affect the eyes? A review of Coronaviruses and ocular implications in humans and animals. Ocul Immunol Inflamm. 2020 Apr 2; 28 (3): 391–5. doi: 10.1080/09273948.2020.1738501
3. Ali MJ. The SARS-CoV-2, tears, and ocular surface debate: What we know and what we need to know. Indian J Ophthalmol. 2020 Jul; 68 (7): 1245–6. doi: 10.4103/ijo.IJO_1881_20
4. Ziegler CGK, Allon SJ, Nyquist SK, et al. SARS-CoV-2 receptor ACE2 is an interferon-stimulated gene in human airway epithelial cells and is detected in specific cell subsets across tissues. Cell. 2020 May 28; 181 (5): 1016–35.e19. doi: 10.1016/j.cell.2020.04.035
5. Zhong Y, Wang K, Zhu Y, et al. Ocular manifestations in COVID-19 patients: A systematic review and meta-analysis. Travel Med Infect Dis. 2021 Nov-Dec; 44: 102191. doi: 10.1016/j.tmaid.2021.102191
6. Karimi S, Arabi A, Shahraki T, Safi S. Detection of severe acute respiratory syndrome Coronavirus-2 in the tears of patients with Coronavirus disease 2019. Eye. 2020: 1220–3. https://doi.org/10.1038/s41433-020-0965-2
7. Ho D, Low R, Tong L, et al. COVID-19 and the ocular surface: a review of transmission and manifestations. Ocul Immunol Inflamm. 2020 Jul 3; 28 (5): 726–34. doi: 10.1080/09273948.2020.1772313
8. Aggarwal K, Agarwal A, Jaiswal N, et al. Ocular surface manifestations of coronavirus disease 2019 (COVID-19): a systematic review and meta-analysis. PLoS One. 2020 Nov 5; 15 (11): e0241661. doi: 10.1371/journal.pone.0241661
9. Sen S, Kannan NB, Kumar J, et al. Retinal manifestations in patients with SARS-CoV-2 infection and pathogenetic implications: a systematic review. Int Ophthalmol. 2021; 1–14.
10. Cheema M, Aghazadeh H, Nazarali S, et al. Keratoconjunctivitis as the initial medical presentation of the novel coronavirus disease 2019 (COVID-19). Can J Ophthalmol. 2020 Aug; 55 (4): e125–e129. doi: 10.1016/j.jcjo.2020.03.003
11. Liu K, Chen Y, Lin R, Han K. Clinical features of COVID-19 in elderly patients: a comparison with young and middle-aged patients. J Infect. 2020 Jun; 80 (6): e14–e18. doi: 10.1016/j.jinf.2020.03.005
12. Invernizzi A, Schiuma M, Parrulli S, et al. Retinal vessels modifications in acute and post-COVID-19. Sci Rep. 2021; 11 (1): 19373. https://doi.org/10.1038/s41598-021-98873-1
13. Modjtahedi BS, Do D, Luong TQ, et al. Changes in the incidence of retinal vascular occlusions after COVID-19 diagnosis. JAMA Ophthalmol. 2022 May 1; 140 (5): 523–7. doi: 10.1001/jamaophthalmol.2022.0632
14. Bwire GM. Coronavirus: Why men are more vulnerable to Covid-19 than women. SN Compr Clin Med. 2020; 2 (7): 874–6. doi: 10.1007/s42399-020-00341-w
15. Yang J, Zheng Y, Gou X, et al. Prevalence of comorbidities and its effects in patients infected with SARS-CoV-2: a systematic review and meta-analysis. Int J Infect Dis. 2020 May; 94: 91–5. doi: 10.1016/j.ijid.2020.03.017
16. Çetin Kargin N. The effect of smoking on COVID-19-linked biomarkers in hospitalized patients with COVID-19. J Clin Lab Anal. 2021 Oct; 35 (10): e23983. doi: 10.1002/jcla.23983
17. Wu P, Duan F, Luo C, et al. Characteristics of ocular findings of patients with coronavirus disease 2019 (COVID-19) in Hubei Province, China. JAMA Ophthalmol. 2020 May 1; 138 (5): 575–8. doi: 10.1001/jamaophthalmol.2020.1291
18. Casagrande M, Fitzek A, Puschel K, et al. Detection of SARS-CoV-2 in human retinal biopsies of deceased COVID-19 patients. Ocul Immunol Inflamm. 2020 Jul 3; 28 (5): 721–5. doi: 10.1080/09273948.2020.1770301
19. Marinho P, Marcos A, Romano A, et al. Retinal findings in hospitalised patients with severe COVID-19. Lancet. 2020 May 23; 395 (10237): 1610. doi: 10.1016/S0140-6736(20)31014-X
20. Pereira LA, Soares LCM, Nascimento PA, et al. Retinal findings in hospitalised patients with severe COVID-19. Br J Ophthalmol. 2022 Jan; 106 (1): 102–5. doi:10.1136/bjophthalmol-2020-317576
21. Landecho MF, Yuste JR, Gándara E. COVID-19 retinal microangiopathy as an in vivo biomarker of systemic vascular disease? J Intern Med. 2021 Jan; 289 (1): 116–20. doi: 10.1111/joim.13156
22. Abrishami M, Emamverdian Z, Shoeibi N, et al. Optical coherence tomography angiography analysis of the retina in patients recovered from COVID-19: a case-control study. Can J Ophthalmol. 2021 Feb; 56 (1): 24–30. doi: 10.1016/j.jcjo.2020.11.006
23. Abrishami M, Tohidinezhad F, Emamverdian Z, et al. Macular thickness and volume assessed by spectral-domain optical coherence tomography in patients with coronavirus disease 2019: a case-control study. Int Ophthalmol. 2021; 41 (5): 1703–10. doi:10.21203/rs.3.rs-133611/v1
24. Pirraglia MP, Ceccarelli G, Cerini A, et al. Retinal involvement and ocular findings in COVID-19 pneumonia patients. Sci Rep. 2020; 10 (1): 17419. https://doi.org/10.1038/s41598-020-74446-6
25. Invernizzi A, Torre A, Parrulli S, et al. Retinal findings in patients with COVID-19: results from the SERPICO-19 study. EClinicalMedicine. 2020; 27: 100550. doi: 10.1016/j.eclinm.2020.100550
26. Patel NS, Moon JY, Katz R, et al. Retrospective analysis of retinal imaging in COVID-19 positive patients at a tertiary eye care center. Clin Ophthalmol. 2021 Sep 3; 15: 3727–31. doi: 10.2147/OPTH.S309346
27. Sim R, Cheung G, Ting D, et al. Retinal microvascular signs in COVID-19. Br J Ophthalmol. 2022 Sep; 106 (9): 1308–12. doi: 10.1136/bjophthalmol-2020-318236
28. Jiang L, Yang Y, Gandhewar J. Bilateral corneal endothelial failure following COVID-19 pneumonia. BMJ Case Rep. 2021 Sep 20; 14 (9): e242702. doi: 10.1136/bcr-2021-242702
29. Erdem S, Karahan M, Ava S, et al. Examination of the effects of COVID-19 on corneal endothelium. Graefes Arch Clin Exp Ophthalmol. 2021 Aug; 259 (8): 2295–300. doi: 10.1007/s00417-021-05259-0
Review
For citations:
Jaaz M.H., Fahad A.A. Assessment of retinal vessels and corneal endothelium alterations in acute and post-COVID-19. Russian Ophthalmological Journal. 2025;18(4):57-61. https://doi.org/10.21516/2072-0076-2025-18-4-57-61

























