Quantitative assessment of retinal changes in COVID-19 patients

The SARS-COV 2 virus, which is responsible for the COVID-19 pandemic, acts on the angiotensin converting enzyme 2 (ACE-2) receptor in the host cell. Ocular effects may occur because of the ACE-2 receptor in the retina.

To investigate the impact of COVID-19 on the retinal layers and optic disc parameters in previously confirmed COVID-19 patients using spectral domain optical coherence tomography (SD-OCT).

This study included 60 eyes of 60 subjects; 35 of them were in the COVID-19 group and the remaining 25 were in the control group. Patients with the diagnosis of COVID-19 that had a negative result after treatment were included in the study. Macular and peripapillary retinal nerve fiber layer (RNFL) thickness measurements, each retinal layer thickness of all participants were done 14-30 days after COVID-19 symptom onset, following the negative result of real time reverse transcriptase-polymerase chain reaction test using SD-OCT.

The mean value of central macular thickness was significantly higher in the COVID-19 group than the control group (p = 0.02). The mean values of the ganglion cell layer and inner nuclear layer thickness in the COVID-19 group were significantly thinner than control group (p = 0.04 and p = 0.04, respectively). Even though mean RNFL thickness measurements in all sections in the COVID-19 group was thinner than controls, there were no significant differences between groups (p > 0.05 for all).

In the early recovery phase, changes in the macula, ganglion cell layer and inner nuclear layer could be seen. These patients should be followed up closely for the recognition of new pathologies that could be seen in the late recovery phase.