Abstract
PURPOSE: To evaluate the long-term efficacy of the bimatoprost sustained-release (SR) implant focusing on time to additional intraocular pressure (IOP) lowering intervention and changes in medication burden and IOP, with subgroup analyses by lens status and prior trabecular meshwork (TM) procedures. PATIENTS AND METHODS: This retrospective study included patients who received a single bimatoprost SR implant between September 2020 and June 2022 at a single center. Data was obtained from electronic medical records. The primary outcomes were time to failure defined as addition of IOP-lowering medications, procedures, or surgery, changes in topical medication use, and IOP over time. Kaplan-Meier survival analysis and linear mixed-effects models were used to assess overall outcomes and within subgroups. RESULTS: The study included 223 eyes from 134 patients. At 6-, 12-, and 24-months post-implantation, 67.3%, 38.5%, and 20.5% of eyes, respectively, remained free of additional IOP-lowering treatment. The rates of survival were not statistically significant when stratified by lens status or history of TM procedures. The mean number of topical medications was 1.8 ± 1.3 at baseline and was significantly reduced beginning at 1 month and through 18 months (p < 0.001). There was not a significant IOP decrease post implantation. Subgroup analysis showed no significant differences in IOP and a borderline significant difference in medication use (p = 0.051) between phakic and pseudophakic eyes. Eyes with a history of TM procedures had higher IOP compared to those without prior intervention (p = 0.042), and medication use was not significantly different between groups. CONCLUSION: In this retrospective, single-center study the bimatoprost SR implant provided significant reduction in topical medication burden for 18 months. The implant provided six months of freedom from additional IOP lowering interventions in more than half of the eyes with an expected decline. A small group continued to be free from additional IOP lowering intervention for up to 24 months.