Clinical Outcomes of Phacoemulsification in Japanese Patients Receiving First and Revised Second-Generation Trabecular Microbypass Stents

Abstract

Purpose: This study evaluated the effectiveness and safety of first and revised second-generation trabecular microbypass stent insertion [iStent (IS) and iStent inject W (IW)] in cataract surgery.

Design: Single-center, retrospective, cohort study.

Methods: The study included 176 eyes that received trabecular microbypass stents combined with cataract surgery at the Saitama Red Cross Hospital between September 2017 and September 2021. Patients were divided into IS and IW groups depending on the implant type. Demographic characteristics, intraocular pressure (IOP), and the number of antiglaucoma medications (Med) were analyzed preoperatively and 12 months postoperatively. In addition, postoperative complications were compared between the groups.

Results: IS and IW were implanted in 86 eyes and 90 eyes, respectively. IOP and Med at 1, 3, 6, 9, and 12 months decreased significantly from baseline in both groups ( P = 0.04, P < 0.001, P < 0.001, P < 0.001, and P < 0.001, respectively, for IOP in the IS group; P = 0.02, P < 0.001, P < 0.001, P < 0.001, and P < 0.001, respectively, for IOP in the IW group; P = 0.03, P = 0.002, P < 0.001, P < 0.001, and P < 0.001, respectively, for Med in the IS group; and P < 0.001 for all time points for Med in the IW group). IOP did not vary significantly between the groups at 1, 3, 6, 9, and 12 months postoperatively. Med was significantly lower in IW than IS at 1, 3, 6, 9, and 12 months postoperatively ( P < 0.001, P < 0.001, P = 0.002, P = 0.002, and P = 0.002, respectively). Hyphema and IOP >30 mm Hg (spike) occurred in 1.2% and 4.4%, and 1.2% and 3.3% of patients in the IS and IW groups, respectively. The probability of successful discontinuation of medications at 12 months postoperatively was 10.5% and 41.1%, respectively ( P < 0.001).

Conclusions: Postoperative Med was significantly lower in the IW group. Simultaneous insertion of IW in patients with glaucoma requiring cataract surgery may be preferred to IS because it reduces the burden of Med.