Trabecular micro-bypass stent demonstrates excellent efficacy

Bypass stent effective at substantial IOP lowering in German study

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fritz-hengerer-hs Fritz Hengerer
A second-generation trabecular micro-bypass stent has demonstrated excellent efficacy and safety data in patients with open-angle glaucoma, according to Fritz Hengerer MD, PhD. “Our results at 18 months shows that the iStent inject trabecular micro-bypass stent (Glaukos Corp.) demonstrated substantial intraocular pressure (IOP) and medication reduction when implanted either as a sole procedure or during cataract surgery. The device was well tolerated by patients and has an excellent safety profile,” Dr Hengerer told delegates attending the XXXIV Congress of the ESCRS in Copenhagen, Denmark. The iStent inject is comprised of two preloaded stents in a single-use, sterile injector designed to deliver the stents ab interno through a clear corneal incision into Schlemm’s canal with a straightforward click-and-release motion, said Dr Hengerer, Senior Head Physician/Deputy Director, Department of Ophthalmology, Heidelberg University, Germany. Made from surgical-grade non-ferromagnetic titanium coated with heparin, the iStent inject stent is approximately 0.3mm in diameter and 0.4mm long. Dr Hengerer presented the results of a retrospective analysis of a case series of 62 eyes of 43 patients with open-angle glaucoma, narrow-angle glaucoma, pseudoexfoliative glaucoma or secondary glaucoma implanted with the iStent inject device. The iStent was implanted as a standalone procedure in 32 eyes, and during cataract surgery in the remaining 30 eyes. As part of the 18-month follow-up, researchers documented IOP, ophthalmic hypertensive medications, best corrected visual acuity (BCVA), cup/disc ratio, and second surgical procedures. EFFICACY RESULTS Preoperatively, 34% of patients had undergone prior glaucoma surgeries and 73% were on 3-4 medications. The average patient age was 70.7 years (± 10.7), with a mean preoperative IOP of 26.1mmHg (±5.2), and mean preoperative medications of 2.7 (±1.0). Prior glaucoma surgery included trabeculectomy in 11, cyclophotocoagulation in five, goniotomy in one, trans-scleral implant in two, iStent implant in three, iridotomy in three and selective laser trabeculoplasty (SLT) in one eye. Looking at the efficacy results, Dr Hengerer said that the mean IOP decreased from 26.1mmHg (±5.2) pre-op to 13.6mmHg (±2.1mmHg) at one year and 13.6mmHg (±1.9mmHg) at 18 months. At month 18, there was a 48% overall decrease from the mean medicated IOP preoperatively. Mean medication use also decreased significantly over the follow-up period. Preoperatively, 73% of patients were on 3-4 medications, whereas 87% of patients were on 0-1 medication at 18 months. Overall, at month 18 there was a 76% decrease in mean medication burden, with 61% using no medications at all and 26% were on one medication, said Dr Hengerer. In terms of safety, BCVA remained stable over time with no significant changes in visual acuity for near or distance vision during the follow-up period, he concluded. Fritz Hengerer: fritz.hengerer@med.uni-heidelberg.de