Comparing the efficacy of trabeculectomy and XEN gel microstent implantation for the treatment of primary open-angle glaucoma: a retrospective monocentric comparative cohort study

The aim of this study was to compare the efficacy and safety profile of XEN microstent implantation with trabeculectomy (TET) in a comparable group of open-angle glaucoma cases in a retrospective, monocentric, single-surgeon setting. Each treatment group consisted of 100 eyes of 100 patients. At regular follow-up visits during the first 12 months after surgery, the following assessments were conducted and compared: intraocular pressure (IOP), number of IOP-lowering medications applied, best-corrected visual acuity (BCVA) and visual field testing. In both groups mean IOP was significantly reduced (p<0.001). Mean IOP dropped from 24.8<plus/minus>7.8 to 14.8 +/- 4.0 mmHg in the TET and from 24.5 +/- 6.7 to 16.6 +/- 4.8 mmHg in the XEN group. The number of active compounds in the prescribed medication dropped from 3.3 +/- 1.2 to 1.3 +/- 1.4 in the TET and from 3.0 +/- 1.1 to 1.4 +/- 1.5 in the XEN group. BCVA and mean defect of static automated perimetry did not show a change of statistical significance in either group. Complications were more frequent after TET (p=0.005) while postoperative needling was more frequent in the XEN group (p=0.021). TET and XEN led to a significant reduction of IOP and IOP-lowering medication, while BCVA and visual field indices remained mostly unaltered over a 12-month postsurgical follow-up.