The influence of universal face mask use on endophthalmitis risk after intravitreal anti-VEGF injections during the COVID-19 pandemic.

OBJECTIVE: Routine use of face masks for patients and physicians during intravitreal anti-vascular endothelial growth factor (VEGF) injections has increased with the emergence of the COVID-19 pandemic. This study evaluates the impact of physician, ancillary staff, and patient face mask use on rates and outcomes of post-injection endophthalmitis. DESIGN: Retrospective, multicenter, comparative cohort study PARTICIPANTS: Eyes receiving intravitreal anti-VEGF injections from 10/1/2019 to 7/31/2020 at twelve centers from the United States of America. INTERVENTION: Cases were divided into a "no face mask" group if no face masks were worn by the physician or patient during intravitreal injections or a "universal face mask" group if face masks were worn by the physician, ancillary staff, and patient during intravitreal injections. MAIN OUTCOME MEASURES: Rate of endophthalmitis, microbial spectrum, and visual acuity. RESULTS: Of 505,968 intravitreal injections from 110,547 eyes administered, 85 of 294,514 (0.0289%; 1 in 3,464 injections) cases of presumed endophthalmitis occurred in the "no face mask" group, and 45 of 211,454 (0.0213%; 1 in 4,699) cases occurred in the "universal face mask" group (odds ratio [OR], 0.74; 95%CI, 0.51-1.18; p=0.097). In the "no face mask" group, there were 27 cases (0.0092%; 1 in 10,908 injections) of culture-positive endophthalmitis compared to 9 cases (0.004%; 1 in 23,494) in the "universal face mask" group (OR, 0.46; 95%CI, 0.22-0.99; p=0.041). Three cases of oral flora-associated endophthalmitis occurred in the "no face mask" group (0.001%; 1 in 98,171 injections) compared to one (0.0005%; 1 in 211,454) in the "universal face mask" group (p=0.645). Patients presented a mean (range) 4.9 (1-30) days after the causative injection, and mean logMAR visual acuity at endophthalmitis presentation was 2.04 [∼20/2200] for "no face mask" group compared to 1.65 [∼20/900] for the "universal face mask" group (p=0.022), although no difference was observed three months after treatment (p=0.764). CONCLUSION: In a large, multicenter, retrospective study, physician and patient face mask use during intravitreal anti-VEGF injections did not alter the risk of presumed acute-onset bacterial endophthalmitis, but there was a reduced rate of culture-positive endophthalmitis. Three months following presentation, there was no difference in visual acuity between the groups.