Posture-Induced Changes in Intraocular Pressure after Ab Externo XEN45 Gel-Stent Implantation in Patients with Primary Open-Angle Glaucoma

Abstract Background: To investigate posture-induced changes in intraocular pressure (IOP) after ab externo XEN45 Gel-Stent implantation in patients with medically uncontrolled primary open-angle glaucoma (POAG). Methods: This prospective study included thirty-two eyes with POAG that underwent XEN45 Gel-Stent implantation as a standalone procedure using an ab externo approach at Chonnam National University Hospital. IOP was measured sequentially in the sitting position, supine position, and lateral decubitus position (LDP) before and at 1, 2, 3, and 6 months after surgery using an iCare IC200 rebound tonometer. In the LDP, the eye with XEN45 Gel-Stent implantation was in the dependent position. Results: IOP at each position was significantly reduced after XEN45 Gel-Stent implantation. Posture-induced changes in IOP were maintained during the follow-up. The range of postural IOP changes was reduced at 1 month; however, no significant change was observed after that point compared with baseline levels. Conclusions: A XEN45 Gel-Stent inserted using the ab externo approach can reduce IOP in various body positions, but seems to have limited effects on posture-induced changes in IOP in patients with POAG.