Multicenter Survey with a Systematic Overview of Acute-Onset Endophthalmitis after Transconjunctival Microincision Vitrectomy Surgery

Purpose To explore the incidence and visual outcomes of acute-onset endophthalmitis after transconjunctival microincision vitrectomy surgery (MIVS). Design Retrospective, interventional, multicenter survey with a systematic review. Methods A clinical database search was performed at 27 institutions involving 43 868 consecutive patients who underwent vitrectomy between November 2003 and October 2008 to identify all patients with endophthalmitis after vitrectomy. A systematic review of studies reporting the endophthalmitis rates after MIVS versus 20-gauge vitrectomy was conducted to assess the pooled incidence rates of postvitrectomy endophthalmitis. Results The endophthalmitis rates from the multicenter survey were 0.034% (10 cases per 29 030 eyes) after 20-gauge vitrectomy and 0.054% (8 cases per 14 838 eyes) after MIVS, with no significant ( P = .603) differences between groups. Although the incidence in 25-gauge cases (6 per 8238 eyes; 0.073%) was greater than in 23-gauge cases (2 per 6600 eyes; 0.030%), the difference was not significant ( P = 0.451). Of 8 eyes in which endophthalmitis developed after MIVS, 6 eyes (75%) had a final visual acuity of 0.5 or better, and none lost light perception. By combining the results of 7 studies, including the current multicenter survey, meta-analyses from a total of 77 956 cases at the baseline showed that the pooled endophthalmitis rates after MIVS (0.08%; 95% confidence interval, 0.030% to 0.164%) and after 20-gauge vitrectomy (0.030%; 95% confidence interval, 0.012% to 0.048%) did not differ significantly ( P = .207, pooled risk difference; 0.0005 [95% confidence interval, −0.0002 to 0.0012]). Conclusions The incidence of postvitrectomy endophthalmitis was low with no significant differences between MIVS and 20-gauge vitrectomy.