Long-Term Outcomes of Bleb Needling Following Primary Glaucoma Filtering Surgery in Primary Open Angle Glaucoma

Purpose: To determine the long-term success rate of bleb needling in a predominantly African American population and to identify factors associated with success. Methods: We conducted a retrospective, observational clinical study in patients with primary open angle glaucoma. Patients who underwent a primary trabeculectomy, with or without an express shunt placement, and then subsequently had a bleb needling procedure were selected for this study. Patients were followed every three months for a period of two years. Failure criteria included achieving an intraocular pressure (IOP) of greater than 20 mmHg or greater than 80% of the pre-needling value on two subsequent visits, an increase in the number of prescribed medications relative to pre-needling quantity, and the occurrence of other complications. Kaplan-Meier survival curves were used to calculate bleb needling success rates and variables associated with failure were analyzed using multivariate Cox regression analysis. Results: Seventy-four eyes from 71 patients were included in the study, with the majority of eyes from African Americans. The overall success rate at 12 months and two years was 28.1% and 14.3%, respectively. However, the complete success rate (completely weaned off of medications) was 12.7% and 5.1% at 12 months and 2 years, respectively. The most frequent reasons for failure included increased number of glaucoma medications (40%), surgical revision (31.7%), and IOP that exceeded threshold (21.7%). Conclusions: The two-year bleb needling success rate reported in our study is lower than that reported in other studies, possibly due to the increased severity of glaucoma in our patient population