Clinical Outcomes of XEN45 Gel Stent Implantation (Ab Externo, Open Conjunctival Approach) versus Trabeculectomy: A Real-World Study

Abstract

Purpose: To compare the clinical outcomes of XEN45 gel stent implantation surgery (ab externo, open conjunctiva) with those of trabeculectomy.

Methods: We retrospectively reviewed electronic medical record of 57 patients (62 eyes) treated with XEN implantation surgery (ab externo, open conjunctival approach) between April 1, 2021, and July 31, 2023, by the same surgeon. Preoperative clinical data including intraocular pressure (IOP), the number of glaucoma medications, and visual acuity were collected from 1 day to 12 months postoperatively. These data were compared and analyzed with those of 67 patients (78 eyes) received trabeculectomy between February 1, 2017, and April 30, 2022, by the same surgeon. Statistical analyses were performed with p < 0.05 as significant.

Results: Complete surgical success rate was 33.9% and 57.7% of the XEN and trabeculectomy groups, respectively (p = 0.005). The qualified success rate was 79.0% and 93.6%, respectively (p = 0.011). Postoperatively, the XEN group used more glaucoma medications than the trabeculectomy group (1.21 ± 1.05 vs. 0.69 ± 0.90, p = 0.003 at postoperative month 12). After postoperative month 1, the XEN group had a higher IOP (15.77 ± 5.07 mmHg vs. 13.17 ± 3.81 mmHg; at postoperative month 12, p = 0.001) and lower corneal astigmatism than the trabeculectomy group (1.32 ± 0.79 diopters vs. 1.88 ± 1.45 diopters, p = 0.020 at postoperative month 6). There was no significant difference in preoperative and postoperative best-corrected visual acuity (logMAR) between the groups at any of the follow-up period (favorable visual acuity subgroup; logMAR < 0.7). Postoperative complications were 0 cases of XEN group and 13 cases of trabeculectomy group (0% vs. 16.7%, p = 0.001). Also, XEN surgery (24 minutes 40 seconds ± 6 minutes 26 seconds) had a shorter operation time than the trabeculectomy (40 minutes 18 seconds ± 8 minutes 27 seconds, p < 0.001).

Conclusions: Compared to trabeculectomy, XEN surgery (ab externo, open conjunctiva) showed relatively lower effectiveness (surgical success rate, IOP reduction). However, it demonstrated advantages as a minimally invasive glaucoma surgery, including a surgical success rate approaching about 80%, stability in inducing corneal astigmatism, fewer postoperative complications, and shorter operation times.