This IRIS® Registry-based study assessed the incidence and visual outcomes of acute-onset endophthalmitis after cataract surgery in the United States.

Study design

This retrospective cohort study comprised 5,401,686 patients undergoing cataract surgery in the United States between 2013 and 2017. Researchers used the IRIS Registry to identify cases of acute-onset postoperative endophthalmitis cases occurring within 30 days after surgery. They determined the annual and aggregate 5 year incidence, with a focus on standalone procedures vs procedure combined with other ophthalmic surgeries. Patient characteristics and visual acuity were assessed at 1 month preoperatively as well as 1 week, 1 month and 3 months postoperatively.

Outcomes

Of the 8,542,838 eyes that underwent cataract surgery, 3,629 developed acute-onset endophthalmitis (0.04%). Over the study period, the incidence of endophthalmitis was highest among patients in the age group of 0 to 17 years, followed by those aged 18 to 44 years (0.37% and 0.18%, respectively; P < 0.0001).

Endophthalmitis was more common among combined cases (cataract with other ophthalmic procedures) than standalone cataract surgeries (0.20% vs 0.04%) and occurred in 0.35% of patients receiving anterior vitrectomy. At 3 months postop, the mean visual acuity of patients with endophthalmitis was 20/100 vs approximately 20/40 among the non-endophthalmitis group. However, 4% of endophthalmitis cases still achieved 20/20 or better visual acuity and 44% achieved 20/40 or better.

Limitations

The IRIS Registry is fraught with the same problems as any registry-based survey. The study outcomes are dependent on the quality of data entered by numerous centers around the United States. Furthermore, it is not clear if cases of reported endophthalmitis were culture proven or presumed.

Clinical significance

This study found that acute-onset endophthalmitis occurred in 0.04% of the nearly 8.5 million real-world cataract surgeries performed in the United States between 2013 and 2017. Risk factors may include younger age, cataract surgery combined with other ophthalmic procedures, and anterior vitrectomy. Although visual acuity outcomes vary, patients can recover excellent vision after surgery.