"Vision Loss" and COVID-19 Infection: A Systematic Review and Meta-Analysis

Background: Visual impairment in terms of reduced visual acuity and "visual loss" has been reported as an atypical symptom in patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. This systematic review and meta-analysis aims to assess the cumulative incidence of "visual loss" during coronavirus disease 2019 (COVID-19) and review the current evidence regarding "visual loss" caused by SARS-CoV-2 infection. Methods: We performed a systematic review and meta-analysis of studies following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We systematically searched the PubMed, Embase, and Scopus databases for relevant studies published that clearly described "vision loss" and SARS-CoV-2 infection. All studies reporting concomitant "vision loss" and laboratory-confirmed SARS-CoV-2 infection were included. Meta-analyses were conducted using the measurement of risk and a 95% confidence interval for each study. Results: Our search identified 1143 manuscripts published in the English language. After study screening, twenty-nine articles were selected: two cross-sectional studies, twenty-four case reports, and three case series. A random-effect meta-analysis demonstrated that the pooled "visual loss" cumulative incidence in COVID-19 patients was 0.16 (95% CI 0.12-0.21). The quality rating of the cross-sectional studies averaged four out of the maximum score on the Newcastle-Ottawa scale. Conclusions: COVID-19 infection might cause "visual loss". Even if the current evidence is limited, ophthalmological assessment should be promptly provided to all patients experiencing visual impairment symptoms during SARS-CoV-2 infection.