One-Year Outcomes of Standalone XEN Gel Stent Versus Nonpenetrating Deep Sclerectomy

Precis:The nonpenetrating deep sclerectomy (NPDS) procedure resulted in significantly more surgical success than the standalone XEN gel stent procedure without differences in safety profile. Purpose:The purpose of this study was to compare surgical success and safety profile of NPDS and XEN gel stent. Methods:A retrospective chart review of 328 eyes of 282 patients who were scheduled for standalone XEN gel stent surgery (n=140) or NPDS (n=188) at Groupe Hospitalier Paris Saint-Joseph between January 2017 and December 2018 was conducted. Primary outcome measure was the proportion of surgical success 12 months after surgery. Complete and qualified surgical successes were defined by intraocular pressure (IOP)<= 18 mm Hg and a reduction of IOP >= 20% without or with hypotensive medication, respectively. Results:In total, 82 eyes were included in the XEN group and 124 eyes in the NPDS group. In the 1-eye analysis, rates of "complete success" and "qualified success" were, respectively, at the end of follow-up, 28.57% and 20.00% in the XEN group, and 42.72% and 16.50% in the NPDS group (P=0.17). Success probability plots based on the Kaplan-Meier estimate for overall surgical success demonstrated a median success probability time of 3.73 years for the NPDS group and 2.38 years for the XEN group (P<0.0001). After adjustment for confounding variables using Cox regression, the NPDS procedure was significantly more associated with surgical success than the XEN gel stent implantation (P<0.001). No difference was demonstrated in terms of reduction of antiglaucoma medications, needling procedures, or reoperations. Conclusions:The NPDS procedure may be more effective than the XEN gel stent in reducing IOP in patients with open angle glaucoma and may result in longer surgical success. However, a well-conducted prospective randomized study is required to confirm these results.