Stent offers safe, effective, minimally invasive way to lower IOP in open-angle glaucoma patients

Dermot McGrath

Posted: Wednesday, January 4, 2017

Inga Kersten-Gomez MD

Inga Kersten-Gomez MD


The XEN Gel Stent (AqueSys) offers a safe, effective and minimally invasive way to lower intraocular pressure (IOP) in open-angle glaucoma (OAG) patients either as a standalone procedure or as an adjunct to phacoemulsification cataract surgery, according to a study presented at the XXXIV Congress of the ESCRS in Copenhagen, Denmark.

“The long-term efficacy shows good IOP reduction of the order of 39%, and a decrease of glaucoma medication use of around 56% after XEN Gel Stent implantation,” said Inga Kersten-Gomez MD.

The stent’s minimal invasiveness, strong safety profile and long-term efficacy make it a reasonable option as an additional method for surgical glaucoma therapy, sparing the conjunctiva and not blocking further filtration surgery, she added.

Dr Kersten-Gomez, of University Eye Hospital Bochum, Germany, said that the implant is the first ab-interno device which works by creating aqueous outflow from the anterior chamber into the non-dissected tissue of the subconjunctival space.

The procedure uses a collagen-derived, gelatin implant that is soft and flexible when hydrated, creating a soft, flexible drainage channel that conforms to the ocular tissue and cannot migrate or erode. Its gelatin material is biocompatible and is very well tolerated by the ocular tissues, she said.

A prospective, non-randomised, multicentre evaluation (Austria, Canada, Germany – see contributors below) included 66 eyes implanted with the XEN stent, 39 of which reached the four-year follow-up point. All patients had mild or moderate OAG, 51% were solo procedures, and 49% were combined with cataract surgery. Devices with two different inner lumen sizes of 140µm and 63µm were used in the study.

The best-medicated baseline IOP of 22.3mmHg decreased significantly to 13.5mmHg after four years, corresponding to a 39% reduction. The mean number of IOP-lowering medications also decreased significantly from 2.5 preoperatively to 1.1 postoperatively, a 56% reduction.

The visual field mean deviation showed no significant change over the course of the follow-up period. Eleven out of 66 patients (17%) were lost to follow-up and 16 patients (24%) had to be excluded from the final analysis because of secondary IOP-lowering procedures (one selective laser trabeculoplasty/SLT, 12 filtering surgeries, and three cyclodestructive procedures).

Dr Kersten-Gomez added that the results from her study were broadly in line with those reported in the three-year results of the international multicentre feasibility study, which enrolled 986 patients and which demonstrated effective IOP reduction of 32.7% at 12 months in 279 eyes, 33.1% at 24 months in 71 eyes, and 39.8% at 36 months in 33 eyes.

Inga Kersten-Gomez:

For Germany: I. Kersten-Gomez, L. Eisenkopf, H.B. Dick
For Austria: M. Lenzhofer (co-author), H. Reitsamer
For Canada: I. Ahmed