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

Purpose: To describe the outcome of surgical bleb revision for late-onset bleb leaks after trabeculectomy. Patients and Methods: 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. Results: 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. Conclusion: 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.