Combined phacoemulsification and iStent inject implantation in Asian eyes

Purpose: To evaluate the safety and efficacy of the iStent inject device combined with phacoemulsification in Asian eyes with primary open angle glaucoma. Methods: A retrospective study of combined phacoemulsification and iStent inject surgeries performed in a single institution from July 2017 to August 2019 on patients with co-existing cataracts and primary open angle glaucoma (POAG). Outcome measures included best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma eyedrop medications, and surgical complications. Results: A total of 95 eyes were included. Majority of subjects were male (59, 62.1%) and Chinese (83, 87.4%). Mean age was 74.7 +/- 8.7 years. Pre-operatively, mean IOP was 16.2 +/- 4.3 mmHg and number of medications was 1.9 +/- 0.9. Significant post-operative reduction in mean IOP was observed at all timepoints - post-operative month (POM)1: 3.0 +/- 5.6 mmHg reduction (n = 95, p < 0.05); POM3: 1.6 +/- 3.8 mmHg (n = 66, p < 0.05); POM6: 1.8 +/- 4.7 mmHg (n = 55, p < 0.05); POM12: 1.3 +/- 4.2 mmHg (n = 48) (p < 0.05). The number of glaucoma medications was also reduced from a mean of 1.9 +/- 0.8 to 0.6 +/- 1.0 at POM12 (p < 0.05). Intraoperatively, one case of malignant glaucoma occurred. Post operatively, implant obstruction by iris was observed in two eyes post-operatively requiring iridoplasty. One case of cystoid macular edema and one case of drop in visual acuity due to glaucoma progression was/were also observed. Conclusion: Asian eyes undergoing combined phacoemulsification and iStent inject surgery demonstrate a significant and sustained reduction in both IOP and number of glaucoma medications. Overall, there is a good safety profile for iStent inject.