Endophthalmitis Following Intravitreal Anti-Vascular Endothelial Growth Factor Therapy: Changes in Incidence and Outcomes over a 9-Year Period

Aims: To evaluate whether the incidence, microbial spectrum, and visual outcomes of endophthalmitis following intravitreal injections have changed over time. Methods: Retrospective cohort study of endophthalmitis in eyes receiving intravitreal injection of anti-vascular endothelial growth factor between 2009-2012 and 2016-2017 at a single, large retina practice. Results: A total of 283,315 injections resulted in 96 suspected infectious endophthalmitis cases. Comparing 2009-2012 and 2016-2017, the rate of suspected endophthalmitis changed from 1 in 2,663 injections to 1 in 3,195 injections (p = .37). Visual outcomes 6 months after endophthalmitis were significantly better during the latter period (p = .04), with an average loss of 6.3 lines of VA in 2009-2012 compared to a loss of 3.6 lines in 2016-2017. In multivariate analysis, a "no-talking" policy during injections resulted in a trend towards a decrease in endophthalmitis incidence (p = .08). Cessation of post-injection topical antibiotic use did not independently decrease endophthalmitis incidence (p = .24) when the effect of a "no-talking" policy was taken into account. A lower rate of endophthalmitis was seen after prefilled vs. conventionally prepared ranibizumab syringe use for injection (0.014% vs. 0.035%, respectively), though this difference did not meet statistical significance (p = .16). Conclusion: The incidence of endophthalmitis after intravitreal injection decreased and visual outcomes improved between the periods of 2009-2012 and 2016-2017. A "no-talking" policy during injections was associated with a trend toward a decrease in endophthalmitis rate.