Trabeculectomy Following Failed Ab Interno Gelatin Microstent: Case Series.

PURPOSE: The purpose of this study is to describe the outcomes of mitomycin C (MMC)-augmented trabeculectomy performed following a failed MMC-augmented XEN-45 implantation.

DESIGN: Retrospective case series.

METHODS: All consecutive cases of MMC-augmented trabeculectomy performed after MMC-augmented XEN-45 in the Glaucoma Service at Moorfields Eye Hospital between April 2015 and June 2017 were retrospectively reviewed.

RESULTS: We identified 8 patients who had a trabeculectomy following a failed XEN-45 implantation. The median intraocular pressure (IOP) before and after trabeculectomy was 29.0 mm Hg (12 to 45 mm Hg) and 7.5 mm Hg (2 to 12 mm Hg), respectively. At the last follow-up, 6 cases had a single-digit IOP and 2 of them developed hypotony-related complications (1 case of late choroidal detachment and 1 case of hypotony maculopathy). The median number of glaucoma drops and the median visual acuity (logMAR) before and after trabeculectomy were 2.5 (0 to 5), and 0 and 0.17 (0 to 0.3), and 0.3 (0.17 to 0.47), respectively. At the last follow-up, 3 cases showed an avascular bleb.

CONCLUSIONS: Trabeculectomy following a failed XEN-45 implantation seems technically feasible; however, higher than expected number of cases with low IOP and avascular blebs were observed. This might be related to the cumulative effect of MMC in these cases.