<p>Two-Year Multicenter Outcomes of iStent <em>inject</em> Trabecular Micro-Bypass Stents Combined with Phacoemulsification in Various Types of Glaucoma and Ocular Hypertension</p>
Colin Clement, Frank Howes, Alexandros S Ioannidis, Michael Shiu, David Manning, Jed Lusthaus, Ridia Lim, Simon E. Skalicky, Todd Goodwin
Abstract
Purpose: This multicenter study evaluated 2-year effectiveness and safety following implantation of two second-generation trabecular micro-bypass stents (iStent inject ® ) with phacoemulsification. Materials and Methods: This was a retrospective study of iStent inject implantation with phacoemulsification by nine surgeons across Australia. Eyes had mild to advanced glaucoma (predominantly primary open-angle/POAG, appositional angle-closure/ACG, or normal-tension/NTG) or ocular hypertension (OHT), and cataract. Evaluations included intraocular pressure (IOP); medications; proportions of eyes with 0 or ≥ 2 medications, reduced/stable medications versus preoperative, and IOP ≤ 15 mmHg; visual acuity; cup-to-disc ratio (CDR); visual fields (VF); adverse events; and secondary surgery. Results: A total of 340 eyes underwent surgery and had 24-month follow-up data. At 24 months, mean IOP decreased by 16% from 16.4± 4.7 mmHg preoperatively to 13.7± 3.1 mmHg (p< 0.001), and 77% of eyes achieved IOP of ≤ 15 mmHg versus 49% preoperatively (p< 0.001). Mean number of medications decreased by 67% to 0.49± 0.95 versus 1.49± 1.20 preoperatively (p< 0.001), with 74% of eyes medication-free versus 25% preoperatively (p< 0.001), and 14% of eyes on ≥ 2 medications versus 46% preoperatively (p< 0.001). Medication burden was reduced or stable in 98% of eyes versus preoperative. Stratified analyses showed significant IOP and medication reductions across glaucoma subtypes (POAG, ACG, NTG, OHT): 13– 22% for IOP (p< 0.01 for all) and 62– 100% for medication (p< 0.001 for all). Favorable safety included few adverse events; stable CDR, VF, and visual acuity; and filtering surgery in only 8 eyes (2.4%) over 2 years. Conclusion: This 340-eye multicenter dataset provides robust evidence of the safety and efficacy of iStent inject implantation with phacoemulsification, with significant and sustained IOP and medication reductions through 2 years. Results were similarly favorable across glaucoma subtypes (including POAG, ACG, NTG, OHT) and were attained across various glaucoma severities, clinical sites, and surgeons, highlighting the real-world versatility and utility of this treatment modality. Keywords: microinvasive glaucoma surgery, MIGS, glaucoma, iStent inject , intraocular pressure, second-generation, multicenter