Purpose: To assess the efficacy and safety of the XEN Gel Stent in patients with primary open-angle glaucoma.
Materials and methods: Twenty eyes of 17 patients (6 males, 11 females) with primary open-angle glaucoma were implanted with XEN Gel Stent. The following data were ascertained in each participant at baseline and at 1, 3, 6, 9 and 12 months following implanting procedure: intraocular pressure, number of anti-glaucoma medications, retinal sensitivity (PS 24/2 w/w), pattern electroretinogram (ISCEV standard), as well as the number of complications.
Results: The mean intraocular pressure reduction in a 1-year follow-up was 18% (21.56 vs. 17.69 mmHg, p < 0.001). The mean number of anti-glaucoma medications was reduced from 3.2 to 1.6 (p = 0.001). The PERG parameters at baseline and at 12 months postoperatively included a stable amplitude of P50 (2.55 µV vs. 2.65 µV, p = 0.024) and N95 (3.45 µV vs. 3.38 µV, p = ns) waves. The delta N95 and delta P50 amplitudes remained stable over the follow-up period (p = ns). The mean deviation (MD) of PS 24/2 was - 6.54 dB vs. - 8.43 dB, p = ns, whereas the pattern standard deviation (PSD) was 6.18 dB vs. 6.91 dB, p = ns. Transient hypotony within the first postoperative week occurred in 18 eyes (90%), whereas hyphema occurred in two eyes (10%). Needle revision of a filtration bleb was performed in five eyes (25%).
Conclusions: The XEN Gel Stent enables significant reduction in intraocular pressure with very low complication rates. It ensures a stabilization of the retinal function as established with the PERG.
Keywords: Glaucoma; MIGS; Minimally invasive glaucoma surgery; PERG; Pattern electroretinogram; XEN.