Case Series of Combined iStent Implantation and Phacoemulsification in Eyes with Primary Angle Closure Disease: One-Year Outcomes

Purpose: To evaluate the safety and efficacy of combined iStent (R) trabecular micro-bypass device (Glaukos, Laguna Hills, CA) and phacoemulsification in eyes with primary angle closure disease. Methods: A two-center prospective interventional case series of consecutive patients with primary angle closure (PAC) or primary angle closure glaucoma (PACG) on at least one glaucoma medication, who underwent iStent implantation with cataract surgery. Postoperatively, patients were assessed on days 1 and 7, and months 1, 3, 6, and 12. The intraocular pressure (IOP), glaucoma medication use, visual acuity, and the presence of complications were assessed at each visit. Complete success was defined as IOP reduction of at least 20% without the use of glaucoma medications. Results: Thirty-seven eyes with angle closure disease were included in this study. At 1-year, postoperative mean IOP (14.8 +/- 3.94 mmHg) was significantly decreased compared with preoperative medicated (17.5 +/- 3.82 mmHg, p = 0.008) and unmedicated (24.6 +/- 3.41 mmHg, p < 0.001) IOP. Complete success was achieved in 89.2% of the eyes. The number of glaucoma medications decreased from 1.49 +/- 0.77 to 0.14 +/- 0.48 (p < 0.001). Preoperative medicated IOP was a risk factor for failure (hazard ratio 3.45, 95% confidence interval 1.52-7.85, p = 0.003), after adjustment for age, gender, and race. The most common postoperative complications were iStent occlusion with iris (27.0%) and hyphema (18.9%). There were no sight-threatening intraoperative or postoperative complications. Conclusion: Combined iStent implantation with cataract surgery was effective in lowering the IOP and the number of glaucoma medications for at least 12 months, with a favorable safety profile.