Retinal microvascular changes in patients recovered from COVID-19 compared to healthy controls: A meta-analysis.

PURPOSE: To investigate changes in retinal microcirculation in patients recovered from COVID-19 infection compared to healthy controls, using optical coherence tomography-angiography. METHODS: Meta-analysis of eligible studies comparing retinal microcirculation between patients recovered from COVID-19 infection and healthy controls up to 7th of September 2022 was performed, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 guidelines. The following search algorithm was used: (COVID-19 OR coronavirus) AND (retina OR optical coherence tomography OR optical coherence tomography angiography OR vessel density OR foveal avascular zone). Standardized Mean Difference (SMD) with 95% confidence interval (CI) was calculated to compare continuous variables. Revman 5.3 was used for the analysis. RESULTS: 12 studies were included in our analysis. Foveal avascular zone (FAZ) area was larger in patients recovered from COVID-19 infection compared to healthy controls, while there was no statistically significant difference in FAZ perimeter between the two groups. The foveal, parafoveal and whole image vessel density in the superficial capillary plexus showed no significant difference between the two groups. The foveal, parafoveal and whole image vessel density in the deep capillary plexus was statistically lower in patients recovered from COVID-19 compared to healthy controls. CONCLUSION: FAZ area was enlarged and foveal, parafoveal and whole image vessel density in deep capillary plexus were reduced in patients recovered from COVID-19 infection compared to healthy controls, suggesting that COVID-19 infection may induce long-term retinal microvascular changes in patients recovered from the virus infection.

Effect of COVID-19-Associated Lockdown on Patients With Diabetic Retinopathy.

Purpose To evaluate the effect of the coronavirus disease 2019 (COVID-19)-related lockdown in the management of patients with diabetic retinopathy (DR), including diabetic macular edema (DME), in a tertiary reference center in Greece. Methods In this retrospective study, we first compared the number of patients who were diagnosed with DR or DME in our clinic during the period of the lockdown and during the same period of the previous year. In addition, we included consecutive patients with DR or DME, who were followed up and treated regularly in our clinic and their appointments deferred due to lockdown, so as to compare the visual acuity, fundoscopy, and optical coherence tomography (OCT) findings prior to and post lockdown. Results During the lockdown period, there was a statistically significant decrease in patients with DR and DME as compared to the same period in the previous year. Regarding patients with previously diagnosed DME, there was a statistically significant worsening in their visual acuity and central retinal thickness after lockdown as compared to the last visit before lockdown (p<0.001 for both comparisons). Concerning patients diagnosed with DR and without DME before lockdown, 30% of patients with severe non-proliferative diabetic retinopathy (NDPR) and 8.3% of patients with quiescent proliferative DR (PDR) progressed to active PDR while four out of 107 patients (3.7%) developed DME during the lockdown. Multivariate regression analysis revealed that only the time interval between the last visit before lockdown and the first visit after the lockdown was associated with the best-corrected visual acuity (BCVA) change (p=0.017). Conclusions The COVID-19-related lockdown was related to the postponement in patient care, which resulted in significantly worse visual acuity outcomes in patients with DR.