LAUSR

Purpose To evaluate the effect of physician face mask use on rates and outcomes of post-injection endophthalmitis. Design Retrospective, comparative cohort study Methods . Setting Single-center Study Population Eyes receiving intravitreal anti-vascular endothelial growth factor injections from 7/1/2013 to 9/1/2019. Intervention Cases were divided into “face mask group” if face masks were worn by the physician during intravitreal injections or “no talking group” if no face mask was worn but a no talking policy was observed during intravitreal injections. Main Outcome Measures Rate of endophthalmitis, visual acuity, and microbial spectrum. Results Of 483,622 intravitreal injections administered, 168 out of 453,460 (0.0371%) cases of endophthalmitis occurred in the “no talking” group, and 9 out of 30,162 (0.0298%) cases occurred in the face mask group (odds ratio, 0.81; 95%CI, 0.41–1.57; p=0.527). Sixteen cases of oral flora-associated endophthalmitis were found in the “no talking” group (1 in 28,341 injections) compared to none in the face mask group (p=0.302). Mean logMAR visual acuity at presentation in cases that developed culture-positive endophthalmitis was significantly worse in the “no talking” group compared to the face mask group (17.1 lines lost from baseline acuity vs 13.4 lines lost; p=0.031), though no difference was observed at six months following treatment (p=0.479). Conclusion Physician face mask use did not influence the risk of post-injection endophthalmitis compared to a no talking policy. However, no cases of oral flora-associated endophthalmitis occurred in the face mask group. Future studies are warranted to assess the role of face mask use to reduce endophthalmitis risk, particularly due to oral flora.