One-Year Outcomes of Second-Generation Trabecular Micro-Bypass Stents (iStent Inject) Implantation with Cataract Surgery in Different Glaucoma Subtypes and Severities

Abstract

Purpose: To assess the 1-year efficacy and safety of the implantation of two second-generation trabecular micro-bypass stents (iStent Inject Ò) with concomitant cataract surgery in various subtypes and severities of glaucoma. Methods: This single-surgeon, consecutive case series from a Canadian academic ophthalmology center included subjects with cataract, glaucoma, and the need to reduce intraocular pressure (IOP) and/or medications. The 12-month outcomes included mean IOP and medication burden as well as the proportions of eyes with IOP B 18, B 15, and B 12 mmHg compared to baseline. Other measures included corrected distance visual acuity (CDVA), cup-todisc ratio (CDR), visual field mean deviation (VF MD), retinal nerve fiber layer (RNFL) thickness, ganglion cell inner plexiform layer (GCIPL) thickness, and adverse events. Results: In 118 eyes, mean IOP reduced from 17.00 ± 3.82 mmHg preoperatively to 13.97 ± 2.65 mmHg at the 12-month follow-up mark (17.8% reduction, p \ 0.001), and mean medication burden decreased from 2.31 ± 1.33 preoperatively to 1.03 ± 1.10 medications (56% reduction, p \ 0.001). After 12 months, 93% of eyes achieved IOP B 18 mmHg (versus 69% preoperatively), 70% of eyes achieved IOP B 15 mmHg (versus 42% preoperatively), and 29% of eyes achieved IOP B 12 mmHg (versus 7% preoperatively). For all eyes, topical medications were either maintained or decreased from baseline, with C 1 medication eliminated from the preoperative regimen for 83% of eyes and C 2 medications eliminated for 36% of eyes. Visual acuity improved significantly, consistent with expectations for cataract surgery, while CDR, VF MD, and RNFL and GCIPL thicknesses remained stable. Safety was favorable, with no intraoperative complications and few transient adverse events postoperatively. Conclusion: iStent Inject implantation with cataract surgery safely reduced IOP and medication burden in a real-world clinical population with mild to severe glaucoma, and Enhanced Digital Features To view enhanced digital features for this article go to https://doi.org/10.6084/ m9.figshare.9762590.

Second-generation trabecular micro-bypass stent implantation: Retrospective analysis after 12- and 24-month follow-up

“…The IOP and medication reductions and favorable safety observed in this study are consistent with existing literature on iStent inject, which includes studies of standalone and cataract-combination procedures, different subtypes and severities of glaucoma, and different study designs [30][31][32][33][34][35][36][37][38][39][40][41][42]. A large multicenter pooled analysis showed 12-month outcomes of iStent inject implantation with cataract surgery in various types of glaucoma as well as ocular hypertension.…”

“…In three independent single-surgeon studies with different baseline patient populations, significant IOP and medication reductions were demonstrated following iStent inject with cataract surgery. An Australian case series showed 29.4% IOP reduction and 94.7% medication reduction [41]; a Brazilian case series showed 19.1% IOP reduction and 94.1% medication reduction [33]; and a Canadian study showed 17.8% IOP reduction and 56% medication reduction [42]. In a 3-year prospective case series of patients undergoing iStent inject implantation with cataract surgery in Germany, IOP reduced by 37% (from 22.6 mmHg to 14.3 mmHg) and medications reduced by 68% (a 1.7-medication reduction) [39], with similarly favorable IOP and medication outcomes achieved in POAG and PXG subgroups.…”

Chronic Granulomatous Inflammation after CyPass® Implantation

“…Two of those implants, i.e., the iStent®, which consists of heparin-coated nonferromagnetic titanium, and the Hydrus TM , made of nitinol (nickel-titanium alloy), are metal based. The medical-grade titanium is described as biocompatible with the eyes, with no foreign body reaction after iStent® implantation [12]. Titanium is widely used in bone surgery or dental implants, whereas titanium is no longer seen as “inert” but induces a foreign body reaction that allows osseointegration of the foreign body as a healing process – its long term result is seen as dependent on a “foreign body equilibrium” [13].…”

Prospective Interventional Cohort Study of Ocular Surface Disease Changes in Eyes After Trabecular Micro-Bypass Stent(s) Implantation (iStent or iStent inject) with Phacoemulsification

“…1a) is a 12-item subjective questionnaire designed to assess a patient's symptoms related to chronic dry eye, its severity, and its impact on ability to function [32]. OSDI scores range from 0 to 100, with severity defined as normal (0-12), mild (13)(14)(15)(16)(17)(18)(19)(20)(21)(22), moderate (23)(24)(25)(26)(27)(28)(29)(30)(31)(32), and severe (33-100). The Oxford Schema (Fig.…”

“…Both micro-scale devices are designed to create a patent pathway through the diseased trabecular meshwork into Schlemm's canal, thereby increasing aqueous humor outflow from the anterior chamber and decreasing intraocular pressure (IOP). Stent implantation has been examined in the setting of cataract surgery or as a standalone procedure, in varying glaucoma severities ranging from glaucoma suspect to refractory glaucoma, and in various glaucoma subtypes (e.g., pseudoexfoliative, pigmentary, normal-tension) as well as in primary open-angle glaucoma (POAG) [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. In both long-and short-term followup, stent implantation has consistently demonstrated substantial reductions in IOP and medication burden.…”