Coexistent primary open-angle glaucoma and cataract: Preliminary analysis of treatment by cataract surgery and the iStent trabecular micro-bypass stent

Introduction: Reducing intraocular pressure (IOP) is the only proven treatment modality for reducing the risk of glaucomatous progression. In this study, we evaluated the safety and efficacy of a new tool in IOP reduction, implanted with cataract surgery: the Glaukos iStent trabecular micro-bypass stent. Methods: This was a prospective, 24-month, uncontrolled, non-randomised, multicentre study. Subjects with uncontrolled primary open-angle glaucoma (including pseudoexfoliation and pigmentary) and a cataract underwent clear cornea phacoemulsification cataract extraction with ab-interno gonioscopically guided implantation of the study stent. Subjects who had completed at least 6 months of follow-up were included in this interim analysis (n=47). Results: At baseline, mean (+/- standard deviation) IOP was 21.5 +/- 3.7 mmHg, and subjects were taking a mean of 1.5 +/- 0.7 ocular hypotensive medications. Six months after implantation of the study stent the mean IOP was 15.8 +/- 3.0 mmHg, a mean IOP reduction of 5.7 +/- 3.8 mmHg (25.4%, P < 0.001). The mean number of patient medications after 6 months was 0.5 +/- 0.8 medications, a mean decrease of 1.0 +/- 0.8 medications (66.7%, P < 0.001). Most subjects (70%) were able to discontinue all glaucoma medications. There were no complications traditionally associated with filtering surgery, and no serious adverse events were reported. Conclusion: In this interim analysis of subjects with glaucoma and cataracts, this novel stent implantation in subjects undergoing cataract surgery represents a new surgical approach to provide clinically significant decreases in IOP and drug burden.