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

Abstract

Importance: Additional data are sought regarding treatment options for glaucoma, a major cause of global blindness.

Background: The study assessed outcomes following standalone implantation of two second-generation trabecular micro-bypass stents and postoperative topical prostaglandin in eyes with open-angle glaucoma not controlled on two preoperative medications.

Design: The study design is a prospective, nonrandomized, open-label study at a tertiary-care ophthalmology centre.

Participants: Subjects had open-angle glaucoma with preoperative intraocular pressure of 18-30 mmHg on two medications, a medication washout phase, and post-washout intraocular pressure of 22-38 mmHg. All subjects (N = 53) have been followed for 18 months.

Methods: One day following implantation of two second-generation trabecular micro-bypass stents, subjects started topical travoprost. Medication washout was repeated at month 12.

Main outcome measures: The main outcome measure was the proportion of eyes with intraocular pressure reduction ≥ 20% versus medicated baseline intraocular pressure with reduction of one medication at 12 months.

Results: At 12 months, 91% of eyes achieved intraocular pressure reduction ≥ 20% with reduction of one medication. All eyes had intraocular pressure ≤ 18 mmHg with reduction of one medication, and 87% had intraocular pressure ≤ 15 mmHg. Mean intraocular pressure on one medication was ≤ 13.0 mmHg (≥ 34% reduction) through 18 months. Mean post-washout intraocular pressure at month 13 was 33% lower than preoperative unmedicated intraocular pressure. No adverse events occurred through 18 months.

Conclusions and relevance: In open-angle glaucoma eyes on two preoperative medications, treatment with two second-generation trabecular stents and one postoperative prostaglandin resulted in mean intraocular pressure ≤ 13 mmHg with reduction of one medication, with favourable safety. These findings show the utility of second-generation trabecular bypass with postoperative prostaglandin in patients with open-angle glaucoma.

Keywords: IOP; MIGS; bypass; glaucoma; trabecular.

Figure 1

The iStent inject and iStent inject Trabecular Micro‐Bypass Stent System.

Figure 2

Proportional analysis of postoperative intraocular pressure (IOP) and medication usage (N = 53 at all time points). Med, medication; mmHg, millimetres of mercury.

Figure 3

Mean intraocular pressure (IOP) over time (N = 53 at all time points). SD, standard deviation; mmHg, millimetres of mercury; Pre, preoperative; BL, baseline.

Figure 4

Preoperative and month 18 best‐corrected visual acuity (N = 53 at all time points).