Prospective unmasked randomized evaluation of the iStent inject® versus two ocular hypotensive agents in patients with primary open-angle glaucoma

Abstract

PurposeThe purpose of this study was to compare outcomes of subjects with open-angle glaucoma (OAG) not controlled on one medication who underwent either implantation of two iStent inject® trabecular micro-bypass devices or received medical therapy consisting of a fixed combination of latanoprost/timolol.Patients and methodsOf 192 subjects who qualified for the study and were enrolled, 94 were randomized to surgery with implantation of two iStent inject® devices in the treated eye and 98 to receive medical therapy.ResultsAt the month 12 visit, 94.7% of eyes (89/94) in the stent group reported an unmedicated intraocular pressure (IOP) reduction of ≥20% versus baseline unmedicated IOP, and 91.8% of eyes (88/98) in the medical therapy group reported an IOP reduction ≥20% versus baseline unmedicated IOP. A 17.5% between-group treatment difference in favor of the iStent inject group was statistically significant (P=0.02) at the ≥50% level of IOP reduction. An IOP ≤18 mmHg was reported in 92.6% of eyes (87/94) in the iStent inject group and 89.8% of eyes (88/98) in the medical therapy group. Mean (standard deviation) IOP decreases from screening of 8.1 (2.6) mmHg and 7.3 (2.2) mmHg were reported in the iStent inject and medical therapy groups, respectively. A high safety profile was also noted in this study in both the iStent inject and medical therapy groups, as measured by stable best corrected visual acuity, cup-to-disc ratio, and adverse events.ConclusionThese data show that the use of iStent inject is at least as effective as two medications, with the clinical benefit of reducing medication burden and assuring continuous treatment with full compliance to implant therapy as well as having a highly favorable safety profile.

Outcomes Following Implantation of Two Second-Generation Trabecular Micro-Bypass Stents in Patients with Open-Angle Glaucoma on One Medication: 18-Month Follow-Up

“…Prior studies have evaluated single [3–6] and multiple [7] first-generation stents (iStent) during cataract surgery; multiple first-generation stents as a standalone procedure [8–11]; and two second-generation stents (iStent inject ) either with [12] or without cataract surgery in OAG patients with moderate IOP elevation and/or medication burden [13–16]. In the present study, the observed IOP reduction of 10.2 mmHg was similar to the 7.0–10.5 mmHg reduction observed in these earlier studies of standalone iStent inject implantation in phakic eyes with OAG [13–16]. The present study analyzes IOP and medication use after standalone iStent inject implantation in phakic OAG eyes with IOP not managed to below 18 mmHg on 1 preoperative medication.…”

“…Several studies have demonstrated substantial IOP and medication reduction following implantation of 2 iStent inject devices during cataract surgery [12] or in standalone procedures [13–16]. In addition to their clinical effectiveness, these devices have shown a favorable safety profile, which is an important advantage over traditional surgeries such as trabeculectomy or tube placement, or more recently developed suprachoroidal stents [17, 18].…”

Implantation of two second‐generation trabecular micro‐bypass stents and topical travoprost in open‐angle glaucoma not controlled on two preoperative medications: 18‐month follow‐up

“…1). 12, 13, 14, 15 In this technique, the surgeon advances a single disposable stainless steel inserter through a temporal clear corneal incision, then implants ab internally two pre‐loaded stents into the nasal Schlemm's canal at approximately two clock‐hours apart. Each single‐piece stent is a titanium, heparin‐coated device with dimensions of 360 μm length and 230 μm width, multiple lateral outlet lumens for fluid outflow, and a symmetric design that allows for implantation in either right or left eyes.…”

“…In addition to the body of literature on this first‐generation stent, more recent studies have demonstrated similarly favourable outcomes with the implantation of two second‐generation iStent inject devices (iStent inject ® Trabecular Micro‐Bypass, Glaukos Corporation – San Clemente, CA, USA) either with cataract surgery or in a standalone procedure 12, 13, 14, 15, 16. The MIGS Study Group, which was formed to study outcomes of standalone stent implantation in patients with various degrees of open‐angle glaucoma (OAG), previously reported substantial IOP and medication reduction through 36 months following implantation of two iStent devices and postoperative travoprost in eyes with OAG not controlled on two ocular hypotensive medications 6, 7.…”

Glaukos iStent inject® Trabecular Micro-Bypass Implantation Associated with Cataract Surgery in Patients with Coexisting Cataract and Open-Angle Glaucoma or Ocular Hypertension: A Long-Term Study

“…So far, three case series have revealed the safety and efficacy of the iStent inject device [14–16]. Another randomized study compared outcomes of two iStent inject devices versus two ocular hypotensive agents [17], showing that the use of iStent inject device is at least as effective as two medications. However, the follow-up of these studies was no longer than 12 months.…”