XEN-45 implant results in patients with open angle glaucoma

PURPOSE: To evaluate efficacy and complication of XEN-45 microstent for treatment in open angle glaucoma. MATERIALS and METHODS: In this study, although maximum glaucoma medications IOP≥21 mmHg, 17 eyes of 17 patients, who underwent XEN-45 implantation with 0.2mg/cc MMC were examined retrospectively between June 2016 and February 2018 in our clinic. The best corrected visual acuity (BCVA), change in intraokuler pressure (IOP), number of antiglaucomatous drugs, endothelial cell count (ECC), retinal nerve fiber layer (RNFL), needling number and postoperative complications of the patients before and after surgery were examined. RESULTS: The mean age of the 17 patients (11M, 6F) was 62.6 ± 19.8 (29-94) years. The mean follow-up time of the cases after XEN-45 implantation was 16.8 ± 3.5 (12-21) months. Preoperative diagnosis are primary open angle glaucoma (POAG) in 13 eyes (76%), keratoplasty glaucoma (KPG) in 3 eyes (18%) and angle resession glaucoma (ARG) in 1 eye (8.3%). The mean IOP, which was 27.6 ± 6.0 (21-40) mmHg before glaucoma surgery, was 16.1 ± 7.2 (8-32) mmHg at the first month, 17.2 ± 5.9 (10-32) mmHg at the third month, and 16.2 ± 4.7 (10-27) mmHg at 6 months, 15.1 ± 3.2 (10-21) mmHg at 9 months, 14.1 ± 3.1 (10-18) mmHg at 12 months, 14.1±3.4 (8-19) mmHg at 15. months, 14.5 ±3.3 (8-20) mmHg at last visit, dropped statistically significant (repeated measures ANOVA, p <0.001) The number of antiglaucomatous drugs was 3.9 ± 0.8 (2-5) preoperatively and 1.7 ± 1.3 (0-3) at the final examination, which was statistically significant (wilcoxon test, p =0.001). Preoperative BCVA was 0.78 ± 0.99 LogMAR and 0.8 ± 0.99 LogMAR in last visit did not show any significant change (wilcoxon test, p= 0.99). The EC was 2356.8 ± 533.3 (1635-3275) number / mm2, whereas it was 2338.7 ± 472.7 (1712-3178) number / mm2 at the last control and did not show statistically significant decrease (repeated measures ANOVA, p = 0.470). The preoperative RNFL was 61.4 ± 11.8 (43-82) μ, at the last follow-up was 61.3 ± 11.5 (45-82) μ did not show any significant difference (paired samples t test, p = 0.764). Needling was required in 5 (29.4%) patients, 2 times in one patient and 4 times in 4 patients. Postoperative complications were observed in 4 eyes (23.5%), in the early postoperative period (≤ 1 month) shallow anterior chamber and hypotony in 1 eye which were treated, late complication (> 1month) tenon cyst in 2 eyes and fibrotic bleb in 1 eye. CONCLUSION: Xen-45 implant surgery in open-angle glaucoma patients is an effective surgical procedure for IOP control, requiring needling. After surgery, visual acuity and corneal endothelium was maintained and no serious complication was detected.