PRESERFLO™ MicroShunt Implantation in Patients with Primary Open-Angle Glaucoma: 10-Year Results from a Single-Center Nonrandomized Study

Intraocular implantation of the PRESERFLO^TM MicroShunt has been shown to be effective in lowering intraocular pressure in patients with primary open-angle glaucoma. A single-site, open-label study in the Dominican Republic (NCT00772330) found that MicroShunt implantation resulted in sustained reductions in mean intraocular pressure and glaucoma medications after 1, 3 and 5 years, with no long-term sight-threatening adverse events and with low rates of post-operative interventions. The present study reports results in these patients after 10 years.

The original trial included patients aged 18–85 years with primary open-angle glaucoma inadequately controlled on maximum tolerated medical therapy, with medicated intraocular pressure ranging from 18–40 mmHg, who underwent monocular MicroShunt implantation. Patients who remained in this trial after 10 years, were included. The primary safety endpoint was the incidence of all device- and/or procedure-related adverse events. Secondary endpoints included the mean intraocular pressure and mean reduction in intraocular pressure from baseline, the mean number of glaucoma medications and changes in visual field.

Of the 23 patients initially enrolled in this trial, nine remained after 10 years. Mean medicated intraocular pressure in operated eyes was lower at 10 years than at baseline, with mean percent reductions in intraocular pressure being greater in operated than in non-operated eyes throughout the 10-year period. Glaucoma medication use returned to baseline after 10 years, with none of the nine patients being medication-free. Relative to endothelial cell counts at 5 years, endothelial cell counts at 10 years showed a greater decrease in non-operated than in operated eyes. The percentages of eyes with bullae began to decrease after 1 year, with 67% of eyes having bullae after 10 years. The mean deviation of change in visual field was stable for 36 months, but showed increasing variability thereafter.

The present study showed that the PRESERFLO^TM MicroShunt is an effective and safe long-term option for the surgical management of primary open-angle glaucoma in this study population. Prospective clinical trials are needed to compare the long-term efficacy and safety of MicroShunt implantation with other treatments, such as trabeculectomy.