Incidence of Endophthalmitis after 20- and 25-Gauge Vitrectomy

Purpose To assess the incidence rate of endophthalmitis after 25-gauge pars plana vitrectomy and to compare it with the endophthalmitis rate after 20-gauge pars plana vitrectomy. Design Retrospective, interventional, comparative cohort study. Participants Eight thousand six hundred one consecutive pars plana vitrectomy surgery patients. Methods Surgeries performed at a single institution between January 1, 2004, and September 1, 2006, were reviewed. Main Outcome Measures Incidence of postvitrectomy endophthalmitis. Results Endophthalmitis developed in 1 of 5498 eyes after 20-gauge vitrectomy (0.018%) and in 7 of 3103 eyes after 25-gauge vitrectomy cases (0.23%; P = 0.004). Median final visual acuity was counting fingers or hand movements (range, 20/50–no light perception), with comparable results between 20-gauge and 25-gauge endophthalmitis cases. Conclusions The visual outcomes of vitrectomy-associated endophthalmitis, for both 20-gauge and 25-gauge vitrectomy, is poor. In this study population, 25-gauge vitrectomy had a statistically significant 12-fold higher incidence of endophthalmitis compared with 20-gauge vitrectomy.