Factors influencing the long-term-success of the XEN gel stent

The XEN gel stent is a minimally invasive surgical device for patients with open-angle glaucoma, developed to reduce complications associated with traditional filtration surgery. This study aimed to identify clinical factors that influence long-term surgical success, particularly in the context of postoperative conjunctival scarring. In this retrospective study, 773 eyes of patients with glaucoma treated at a tertiary care center underwent implantation of the XEN gel stent. The primary outcome was long-term surgical success, defined as a reduction in intraocular pressure of at least 20% and achieving a target pressure of 18, 15, or 12 mmHg, either without (complete) or with (qualified) medication. Secondary outcomes included intraocular pressure reduction, change in best-corrected visual acuity and medication use. Potential risk factors were analysed using Kaplan-Meier survival curves and multivariable Cox regression. At 24 months, complete and qualified success for a target pressure of 18 mmHg was achieved in 50% and 64% of cases, respectively; at 72 months, in 35% and 54%. Visual acuity remained stable. Female sex, mitomycin C dose, moderately elevated baseline pressure, and lower pressure on the first postoperative day were associated with significantly higher success rates (p < 0.05). Glaucoma subtype and previous incisional glaucoma surgery had no significant effect. Sex, lower antimetabolite dose and intraocular pressure values before and shortly after surgery are significant predictors of long-term success following XEN gel stent implantation.