Comparison of Outcomes From Delayed-Onset Bleb-Related Endophthalmitis Treated With Pars Plana Vitrectomy Versus Vitreous Biopsy

Abstract

Précis: Bleb-related endophthalmitis (BRE) is a serious complication of glaucoma filtration surgery. The current study reports similar visual and intraocular pressure (IOP) outcomes in eyes treated with pars plana vitrectomy (PPV) compared with vitreous biopsy and injection of intravitreal antibiotics (TI). Purpose: The purpose of this study was to investigate the isolated organisms, visual acuity (VA), and IOP outcomes associated with delayed-onset BRE in eyes treated with PPV versus TI. Patients and Methods: A retrospective chart review was conducted at the Bascom Palmer Eye Institute (Miami, Florida) and the University of Florida (Gainesville, FL) identifying patients treated for BRE with at least 1 month of follow-up from the inception of an electronic health record (2014 and 2011, respectively) through 2021. All patients had undergone bleb-forming glaucoma surgery at least 1 month before endophthalmitis diagnosis. Results: Thirty-nine eyes from 39 patients (33 from Bascom Palmer, 6 from University of Florida) were included. Trabeculectomy was performed in 34 of 39 eyes (87.2%). Streptococcus species (9 eyes, 23.1%) and Staphylococcus species (8 eyes, 20.5%) were the most common isolated organisms and were similar in both treatment groups (P=0.49). Baseline VA was worse in the PPV group (logarithm of the minimum angle of resolution: 2.51 vs. 2.16, P=0.04), but VA at last follow-up was similar (P=0.48) in both groups. After recovery from BRE, the average IOP in the PPV group was 15.1 mm Hg on 0.9 IOP-lowering medications compared with 12.6 mm Hg on 1.2 medications in the TI group (IOP: P=0.56; medications: P=0.80). Additional glaucoma surgery was performed in 44.4% of the PPV eyes and 16.7% of the TI eyes (P=0.09). Conclusion: In eyes with delayed-onset BRE, isolated organisms, visual outcomes, and IOP control were similar after initial PPV compared with TI.

A Brief Review of Historical and Current Trends in Trabeculectomy

“…There are no established guidelines for managing BRI, but a few retrospective studies have reported that 25% to 40% of eyes that received initial vitreous biopsy and intravitreal antibiotics ultimately required pars plana vitrectomy to eradicate the infection. 150,156,157 Bleb Leaks Bleb leaks can be encountered early (within 4 wk of surgery) or late (months to years) in the postoperative period. Reported rates of bleb leakage are 8% to 80% for early onset and 3% to 25% for delayed onset.…”

“…Stage III is considered an ocular emergency and is usually treated aggressively with vitreous biopsy followed by intravitreal and systemic antibiotics alone or in combination with pars plana vitrectomy depending on the severity of vitreous involvement. There are no established guidelines for managing BRI, but a few retrospective studies have reported that 25% to 40% of eyes that received initial vitreous biopsy and intravitreal antibiotics ultimately required pars plana vitrectomy to eradicate the infection 150,156,157 …”