Abisha S., B. Optometry

Aravind Fellowship in Clinical Optometry, Aravind Eye Care System, Chennai, India

There is a famous saying that the eye is the mirror of the soul. The eyes tell us not only about the character of the person but can reflect the physical state of the whole body. Since December 2019, coronavirus disease (COVID-19) caused by a highly transmissible Coronavirus 2 (SARS-CoV-2), has become a global pandemic.⁽¹⁾ Some studies have reported that COVID influences the eyes too. So, it is high time to be aware of the ocular manifestations of COVID.

Anterior ocular manifestations

Patients infected with COVID-19 can present with acute conjunctivitis usually seen in the 1st week of infection. Based on data so far, 1%-3% of people with COVID-19 will get conjunctivitis.⁽³⁾ Follicular conjunctivitis is most seen, haemorrhagic, and pseudomembranous conjunctivitis is also reported.  Symptoms include redness of eyes, irritation, and foreign body sensation, watering of eyes, mucoid discharge, and chemosis. Acute anterior uveitis with blurred vision could be associated with COVID-19.^(1-3)

Posterior ocular manifestations of COVID-19

COVID affects the retina and the choroid through either direct entry or triggering an indirect inflammatory response, mostly resulting in microvascular damage. Some of the signs seen in the retina and choroid are cotton wool spots and intra-retinal haemorrhages, acute macular neuroretinopathy (AMN), and paracentral acute middle maculopathy (PAMM)^(2,6,7). Both central retinal vein occlusion and artery occlusion are also reported because of COVID-19.

Neuro-ophthalmic manifestations of COVID-19

Multiple neuro ophthalmological manifestations have been described in association with COVID-19. Underlying pathophysiological mechanisms include hypoxia, severe hypertension, toxic metabolic processes, ischemic and haemorrhagic stroke.⁽⁴⁾

In the younger population, stroke has been one of the most notable neurological complications of COVID-19.⁽⁴⁾ Visual field defects and visual snow syndrome have been reported with involvement of the posterior circulation and occipital lobes.

Cranial nerve palsies

Diplopia, ptosis, and decreased vision have been reported in patients with COVID-19. Some patients with ocular motor deficits, miller fisher syndrome, and increased intracranial pressure may produce 6th nerve palsy as well as papilledema.⁽⁴⁾

Orbital manifestations of COVID-19

The local microbiological and immunologic environment altered due to avascularity, induced by thrombosis in the setting of COVID-19 infection may lead to orbital cellulitis and intracranial abnormalities. There has been an increasing prevalence of acute invasive fungal rhino-orbital mucormycosis (ROM) co-infection with COVID-19.⁽⁵⁾

Conclusion

COVID has affected so many parts of the body. It’s no surprise that it affects the eye. To conclude, when any patient reports to the clinic with the complaint of blurring of vision during this outbreak of coronavirus, it is mandatory to consider these complications as differential diagnoses. The pathology behind these manifestations is unclear and the ophthalmic features can develop at any point in the disease course. Thus, further research is warranted to know more about these manifestations of COVID in the eye.

References

1. Nasiri, N., Sharifi, H., Bazrafshan, A., Noori, A., Karamouzian, M., & Sharifi, A. (2021). Ocular manifestations of COVID-19: A systematic review and meta-analysis. Journal of ophthalmic & vision research, 16(1), 103.
2. Sen, M., Honavar, S. G., Sharma, N., & Sachdev, M. S. (2021). COVID-19 and eye: A review of ophthalmic manifestations of COVID-19. Indian Journal of Ophthalmology, 69(3), 488.
3. Loffredo, L., Pacella, F., Pacella, E., Tiscione, G., Oliva, A., & Violi, F. (2020).Conjunctivitis and COVID‐19: a meta‐ Journal of medical virology.
4. Gold, D. M., & Galetta, S. L. (2021). Neuro-ophthalmologic complications of coronavirus disease 2019 (COVID-19). Neuroscience Letters, 742, 135531.
5. Hu, K., Patel, J., Swiston, C., & Patel, B. C. (2021). Ophthalmic manifestations of coronavirus (COVID-19). StatPearls (Internet).
6. Silaban, A. H. (2021). New Concept of Ocular Implications in COVID-19 Infection: A Brief Review. European Journal of Medical and Health Sciences, 3(1), 1-5.
7. Zhang, Y., & Stewart, J. M. (2021). Retinal and choroidal manifestations of COVID-19. Current opinion in ophthalmology, 32(6), 536-540.