Face Masking Did Not Affect Endophthalmitis Rates After Anti-VEGF Injections

Face masking during intravitreal anti-vascular endothelial growth factor (VEGF) injections was not linked to a change in the incidence of endophthalmitis in a retrospective study presented at the 128th Annual American Academy of Ophthalmology (AAO) Meeting.

These data showed the incidence of endophthalmitis remained alike in both the face mask and non-face mask cohorts, but masking approached a significant incidence rate after adjustment for prefilled injection status.

“When adjusting for prefilled injection status, masking demonstrated a higher incidence rate (resulting approaching significance) and higher odds ratio of developing endophthalmitis compared to no masking,” wrote the investigative team, led by Sandy Samuel, MD, Wills Eye Hospital.

Since the onset of the COVID-19 pandemic, ophthalmology has experienced an increase in the use of universal face masking during intravitreal anti-VEGF injections. Although previous investigations have explored the impact of a universal face mask policy, these results were limited by the low incidence of endophthalmitis ensuring a low sample size.

This analysis set out to explore the effect of a universal face masking policy on rates of post-anti-VEGF endophthalmitis. The multicenter retrospective study included all patients receiving anti-VEGF injections from January 2025 to September 2023 at 5 centers in the United States.

Participants were then separated into a “no face mask” if no face masks were worn by physician or patient, or a “face mask” cohort if a mask was worn by the patient, provider, and ancillary staff during anti-VEGF injections. A logistic regression model was used to assess the risk of developing endophthalmitis, with outcomes including the rates of endopthhalmitis, culture results, and odds ratio (OR).

Among 1,041,297 administered anti-VEGF injections, 452,293 (43.4%) were in the “face mask” group and 589,004 (56.6%) were in the “no face mask” group. Upon analysis, there were 75 (0.017%) cases of endophthalmitis in the “face mask” group and 99 (0.017%) cases in the “no face mask” group.

Further analysis revealed no significant differences in the odds of developing endophthalmitis in the “face mask” group, compared with the “no face mask” group (OR, 0.99; P = .93). Suspected endophthalmitis cases differed, however, by prefilled injection status.

In the “no face mask” group, 25 cases (0.009%) were suspected with a prefilled syringe, compared with 74 (0.03%) with an anti-VEGF vial (P = .12). On the other hand, in the “face mask” group, 23 patients (0.02%) treated with a vial were suspected to have endophthalmitis, compared with 52 (0.01%) in the prefilled syringe (P = .007).

“Although the mechanism remains unclear, one proposed mechanism include bacterial dispersion toward the eyes with masking,” wrote.

References

_{Samuel S, Massenzio E, Momenaei B, et al. Effect of face masking on incidence of endophthalmitis after intravitreal anti-VEGF injections. Poster presented at American Academy of Ophthalmology (AAO) 2024 Meeting. Chicago, Illinois. October 18-21, 2024.}