Outcomes of Surgical Bleb Revision for Late-onset Bleb Leaks After Trabeculectomy

Abstract

To describe the outcome of surgical bleb revision for late-onset bleb leaks after trabeculectomy. Appropriate cases were identified. Qualified and complete success required intraocular pressure of 21 mm Hg or less with and without glaucoma medication use, respectively. Bleb survival was determined using Kaplan-Meier survival analysis, and overall success rate was defined as qualified success at last follow-up. Preoperative and postoperative ocular parameters were compared using the signed-rank test. Age, sex, ethnicity, time between leak and revision, and surgeon type (attending vs. surgeons in training) were entered into a logistic regression analysis to assess the impact on surgical outcome. Seventy-eight eyes of 75 patients were included. The overall rate of successful bleb revision was 77%, and qualified and complete success at 24 months was 71% and 34%, respectively. Postoperative complications included early and late bleb leaks in 6% and 9% of the eyes, respectively; bleb-related infections in 4% of the eyes; and the need for additional glaucoma surgery in 10% of the eyes. There was no difference in preoperative and postoperative visual acuity (P=0.34) but there was an increase in intraocular pressure (P<0.0001) and the number of medications used (P<0.0001). The number of eyes that did not require glaucoma medication decreased (P=0.002). None of the variables examined had a significant impact on successful surgical outcome. Bleb revision showed a high success rate. About two-thirds of eyes required medication, 10% of eyes required additional glaucoma surgery, and there was a low risk for bleb-related infection following bleb revision.