Spectral Domain Optical Coherence Tomography Assessment of Macular and Optic Nerve Alterations in Patients Recovered from COVID-19: A Comparative Study

Yildiz, Aysegul Mavi; Gunduz, Gamze Ucan; Yalcinbayir, Ozgur; Ozturk, Nilufer Aylin Acet; Avci, Remzi; Coskun, Funda

Objective: To quantify microstructutal alterations in the macula and peripapillary retinal nerve fiber layer (RNFL) in patients recovered from COVID-19 using spectral domain optic coherence tomography (SD-OCT). Design: Retrospective, observational. Participants: This comparative, cross-sectional study included patients who recovered from COVID-19 (Group 1) and age- and sex-matched normal controls (Group 2). Methods: A comprehensive ophthalmic examination including best corrected visual acuity (BCVA), biomicroscopic anterior and posterior segment examination was performed. SD-OCT analysis of the macula and peripapillary RNFL was obtained for each participant. In addition patient demographics and comorbidities were recorded. Results: 238 eyes of 122 subjects (Group 1: n=63; Group 2: n=59) were included. The incidence of coexisting comorbidity was higher in Group 1 (n=26/63, 41.3%) compared with Group 2 (n=12/59, 20.3%) (p=0.013). The central foveal thickness (CFT) was significantly higher in Group 1 (271.0±26.8 μm) than Group 2 (263.2±22.0 μm) (p=0.015). The average outer nuclear layer (ONL) thickness at central fovea in Group 1 (85.4±13.3 μm) was significantly thicker than that in Group 2 (81.4±15.2 μm) (p=0.035). The mean peripapillary RNFL thickness of Group 1 (102.6±8.8 μm) and Group 2 (100.9±8.3 μm) were similar (p=0.145). The mean choroidal thickness of groups at the fovea, at 1500 μm nasal and temporal to the fovea were not significantly different (p>0.05 for all). Conclusion: Significant thickness alterations in individual retinal layers and CFT was detected in post-COVID-19 patients. The increase in CFT and ONL thickness might be attributed to direct infection or viral induced inflammatory response of retina.