Severe SARS-CoV-2 Infection: Late Impact on the Retinal Ganglion Cell Layer Thickness

Purpose: The involvement of the ocular anterior segment by SARS-CoV-2 has been the subject of many studies, however, the repercussions on the posterior segment, particularly on the different layers of the retina and optic nerve, are still little known. The purpose of this study was to evaluate the impact of severe COVID-19 on the retinal ganglion cell layer (RGCL) thickness. Methods: This observational, prospective and analytical study was performed in the Ophthalmology Department of the FACISA University Center, Campina Grande. Three groups were included: group I (control), 29 healthy individuals who had not severe COVID-19;group II (infirmary), 24 individuals who had COVID-19 and were hospitalized in the infirmary;and group III, 25 individuals who had severe COVID-19 and required Intense Care Unit (ICU). All individuals had ophthalmologic examination and assessment of RGCL thickness using Optical Coherence Tomography (OCT). Statistical tests required p ≤ 0.05 to reject the null hypothesis. Results: The mean of RGCL thickness was significantly reduced in individuals from GIII (77.9 ± 8.9 µm), as compared with GII (83.9 ± 10.9 µm) and GI (82.8 ± 6.5 µm) (p = 0.0027). The mean measurements from the retinal neve fiber layer (RNFL) of the optic nerve head were similar. However, when evaluated sectoral, the mean of RNFL at the temporal sector of the optic disc was significantly lower in group GIII (p Conclusion: The RGCL thickness from patients with severe COVID-19 was significantly reduced. This finding supports that the SARS-CoV-2 has systemic action and affinity for nerve cells, including those from the retina and are related to the severity of the infection.

Obese Foveal Avascular Zone Assessed by Optical Coherence Tomography Angiography of the Retina: Is There a Relation to Comorbities?

Purpose: To investigate the foveal avascular zone (FAZ) in obese by optical coherence tomography angiography (OCT-A) and to evaluate the findings of structural optical coherence tomography (OCT) and their relations with comorbidities. Methods: It was included 35 obese (study group) and 30 normal individuals (control group). Patients with retinal diseases and retinal treatments were excluded. The images were obtained using the Topcon®;. Results: The mean areas of FAZ in superficial plexus (FAZ-SP) and deep plexus (FAZ-DP) were significantly greater in the study group: FAZ-SP was 405.0 ± 136.4 μm2 in the obese group and 307.3 ± 78.6 μm2 in the control group and in the left eye (LE) 477.1 ± 124.4 μm2 in the obese group and 384.0 ± 88.7 μm2 in the control group. This difference was statistically significant (RE: p = 0.0014 and LE: p = 0.0012). The mean area of the FAZ-DP was 491.0 ± 124.4 μm2 (Right eye—RE) in the obese group and 384.4 ± 88.7 μm2 in the control group and in the left eye (LE) was 497.9 ± 124.1 μm2 in the obese group and 484.9 ± 92.7 μm2 in the control group. There were no correlations regarding FAZ-SP and FAZ-DP in both eyes with fasting blood glucose, glycated hemoglobin, total cholesterol and fractions and triglycerides. A significant association between enlargement of FAZ-DP and type 2 diabetes mellitus (p = 0.0160) was observed. Conclusion: The FAZ areas in superficial and deep plexus achieved significantly greater values in the study group. There was a significant association between a larger deep FAZ area and type 2 diabetes mellitus. It is necessary an evaluation with a larger sample size to corroborate the findings.