Cypass® micro-stent safety and efficacy at one year: Whahave we learned?

Abstract

Purpose: The suprachoroidal pathway can potentially provide a viable target for intraocular pressure (IOP) control. We present efficacy and safety result for the CyPass® Micro-Stent that provides insight into the use of the suprachoroidal space for IOP reduction. Materials and methods: A retrospective, noncomparative audit of patient records in a university-affiliated National Health Service (NHS) hospital between June 2017 and August 2018. Main outcome measures were IOP reduction and the number of glaucoma drops taken at each time point. Failure and adverse events were noted for each patient. Results: Seventy-seven consecutive case records of 69 patients underwent the CyPass® procedure between August 2017 and August 2018. A stand-alone procedure was performed in 37 (58%) of cases and combined phacoemulsification and CyPass® procedures were performed in 27 (42%) of cases. At baseline, the mean IOP was 24.6 ± 7.2 mm Hg. The mean IOP at 12 months’ follow-up was 16.4 ± 4.5 mm Hg (p < 0.05). At baseline, the mean number of medications was 2.41 ± 0.98, which decreased at 12 months to 1.1 ± 1.3 (p < 0.05). Best corrected visual acuity analysis did not show statistically significant change preoperatively and at each postoperative time point. At 12 months’ postoperative time point, 24% of eyes had failed. Significant IOP spikes were noted in 18 (28.1%) of cases. Conclusion: The suprachoroidal pathway appears to potentially offer an alternative to the classic subconjunctival pathways, yet present a new set of challenges. Further studies would have to address these concerns of endothelial cell loss, IOP spikes, and high failure rate.