Long-term Results of the PRESERFLO MicroShunt in Patients With Primary Open-angle Glaucoma From a Single-center Nonrandomized Study

Precis: The MicroShunt was implanted in 23 patients with primary open-angle glaucoma (POAG) in a feasibility study. Reductions in intraocular pressure (IOP) and medications were sustained for up to 5 years with no long-term sight-threatening adverse events (AEs). Purpose: The purpose of this study was to assess the long-term effectiveness and safety of the PRESERFLO MicroShunt (8.5 mm long, 70 mu m lumen surgical device, formerly known as the InnFocus MicroShunt) in POAG. Patients and Methods: In a feasibility study (NCT00772330), patients with POAG inadequately controlled on maximum tolerated therapy with IOP >= 18 to <= 40 mm Hg underwent MicroShunt implantation with adjunctive mitomycin C (0.4 mg/mL), alone or in combination with cataract surgery. Years 1 to 3 findings have previously been reported. Endpoints of this extension study included IOP reduction and success at years 4 and 5 (primary), incidence of AEs, medication use, and reoperations. Results: Mean IOP was reduced from 23.8 +/- 5.3 mm Hg at baseline to 12.8 +/- 5.6 mm Hg (year 4; n=21) and 12.4 +/- 6.5 mm Hg (year 5; n=21). Overall success (with/without medication use) was 87.0% (year 4) and 82.6% (year 5). The mean number of medications reduced from 2.4 +/- 1.0 at baseline to 0.8 +/- 1.3 (year 5). Common (>= 5% of patients) AEs included corneal edema (n=4), transient hypotony (n=4), bleb-related complications (n=3), and device touching the iris (n=3). There were 4 reports of serious AEs and 2 reoperations. Conclusions: In this extension study, sustained reductions in mean IOP and medications were observed up to 5 years post-MicroShunt implantation. There were no reports of long-term sight-threatening AEs and a low rate of postoperative interventions.