{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T16:53:43Z","timestamp":1776272023201,"version":"3.50.1"},"reference-count":20,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T00:00:00Z","timestamp":1776211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: To compare the five-year efficacy and safety of the 63 \u00b5m (XEN63) vs. 45 \u00b5m (XEN45) XEN\u00ae Gel Stent in patients with open-angle glaucoma (OAG). Methods: This retrospective matched (1:1) cohort study included adults with OAG who underwent standalone ab interno implantation of the XEN63 or the XEN45 between 2014 and 2021 at a tertiary referral center in Belgium. The primary outcome was IOP at five years. The secondary outcomes included surgical success, topical medication use, postoperative hypotony, complications and interventions. Results: Thirty eyes of 30 patients (15 XEN63 and 15 XEN45) were analyzed. The baseline characteristics were comparable. At five years, the mean IOP did not differ between the XEN63 and the XEN45 (11.5 vs. 11.0 mmHg; p = 0.54). The XEN63 demonstrated higher complete success rates than the XEN45 for both the IOP &lt; 18 mmHg (10 vs. four eyes; p = 0.016) and &lt;15 mmHg criteria (10 vs. three eyes; p = 0.003). The topical medication use was low and comparable (0.6 vs. 0.9 medications; p = 0.57). The numerical (13 vs. five eyes; p = 0.008) and symptomatic (six vs. two eyes; p = 0.2) hypotony were more frequent after the XEN63 implantation. The two eyes with XEN63 and none with XEN45 experienced clinically significant hypotony. The needling procedures and secondary glaucoma surgeries were more frequent after the XEN45. Conclusions: The XEN63 implantation was associated with higher long-term success rates and also with a higher incidence of early postoperative hypotony. These findings indicate a trade-off between efficacy and safety and suggest that careful patient selection and postoperative management are essential when considering larger lumen subconjunctival drainage devices.<\/jats:p>","DOI":"10.3390\/jcm15083028","type":"journal-article","created":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T15:56:56Z","timestamp":1776268616000},"page":"3028","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Outcomes of Ab Interno 63 \u00b5m vs. 45 \u00b5m XEN\u00ae Gel Stent in Open-Angle Glaucoma: A Five-Year Follow-Up Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-0424-389X","authenticated-orcid":false,"given":"Thomas","family":"Jacobs","sequence":"first","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"},{"name":"Department of Ophthalmology, University Hospitals UZ Leuven, 3000 Leuven, Belgium"},{"name":"Centre for Eye Research Australia, East Melbourne, VIC 3002, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marie-Isaline","family":"Billen Moulin-Roms\u00e9e","sequence":"additional","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"},{"name":"Department of Ophthalmology, University Hospitals UZ Leuven, 3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-2530-2571","authenticated-orcid":false,"given":"Victor","family":"Raeymaeckers","sequence":"additional","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nawid","family":"Faizi","sequence":"additional","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"},{"name":"Department of Ophthalmology, University Hospitals UZ Leuven, 3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7381-285X","authenticated-orcid":false,"given":"Nathan M.","family":"Kerr","sequence":"additional","affiliation":[{"name":"Centre for Eye Research Australia, East Melbourne, VIC 3002, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9347-3661","authenticated-orcid":false,"given":"Keith R.","family":"Martin","sequence":"additional","affiliation":[{"name":"Centre for Eye Research Australia, East Melbourne, VIC 3002, Australia"},{"name":"Royal Victorian Eye and Ear Hospital, East Melbourne, VIC 3002, Australia"},{"name":"Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC 3010, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7243-9280","authenticated-orcid":false,"given":"Jan Van","family":"Eijgen","sequence":"additional","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"},{"name":"Department of Ophthalmology, University Hospitals UZ Leuven, 3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7507-4512","authenticated-orcid":false,"given":"Ingeborg","family":"Stalmans","sequence":"additional","affiliation":[{"name":"Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium"},{"name":"Department of Ophthalmology, University Hospitals UZ Leuven, 3000 Leuven, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1111\/ceo.14028","article-title":"The Surgical Management of Glaucoma: A Review","volume":"50","author":"Lim","year":"2022","journal-title":"Clin. Exp. Ophthalmol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Traverso, C.E., Carassa, R.G., Fea, A.M., Figus, M., Astarita, C., Piergentili, B., Vera, V., and Gandolfi, S. (2023). Effectiveness and Safety of Xen Gel Stent in Glaucoma Surgery: A Systematic Review of the Literature. JCM, 12.","DOI":"10.3390\/jcm12165339"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1136\/bjophthalmol-2025-egsguidelines","article-title":"European Glaucoma Society\u2014Terminology and Guidelines for Glaucoma, 6th Edition","volume":"109","author":"Pazos","year":"2025","journal-title":"Br. J. Ophthalmol."},{"key":"ref_4","unstructured":"White, F.M. (2016). Fluid Mechanics, McGraw-Hill. [8th ed.]."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1905","DOI":"10.1016\/j.jcrs.2015.01.019","article-title":"Phacoemulsification Combined with a New Ab Interno Gel Stent to Treat Open-Angle Glaucoma: Pilot Study","volume":"41","author":"Sheybani","year":"2015","journal-title":"J. Cataract. Refract. Surg."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"581","DOI":"10.1111\/ceo.13463","article-title":"Four-year Results of a Minimally Invasive Transscleral Glaucoma Gel Stent Implantation in a Prospective Multi-centre Study","volume":"47","author":"Lenzhofer","year":"2019","journal-title":"Clin. Exp. Ophthalmol."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Fea, A.M., Menchini, M., Rossi, A., Posarelli, C., Malinverni, L., and Figus, M. (2021). Early Experience with the New XEN63 Implant in Primary Open-Angle Glaucoma Patients: Clinical Outcomes. JCM, 10.","DOI":"10.3390\/jcm10081628"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Fea, A.M., Menchini, M., Rossi, A., Posarelli, C., Malinverni, L., and Figus, M. (2022). Outcomes of XEN 63 Device at 18-Month Follow-Up in Glaucoma Patients: A Two-Center Retrospective Study. JCM, 11.","DOI":"10.3390\/jcm11133801"},{"key":"ref_9","first-page":"4796548","article-title":"Comparing Medium-Term Clinical Outcomes Following XEN\u00ae 45 and XEN\u00ae 63 Device Implantation","volume":"2020","author":"Zhou","year":"2020","journal-title":"J. Ophthalmol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1829","DOI":"10.1177\/1120672120952033","article-title":"XEN 63 Gel Stent Device in Glaucoma Surgery: A 5-Years Follow-up Prospective Study","volume":"31","year":"2021","journal-title":"Eur. J. Ophthalmol."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"For The Apex Study Group, Reitsamer, H., Sng, C., Vera, V., Lenzhofer, M., Barton, K., and Stalmans, I. (2019). Two-Year Results of a Multicenter Study of the Ab Interno Gelatin Implant in Medically Uncontrolled Primary Open-Angle Glaucoma. Graefes Arch. Clin. Exp. Ophthalmol., 257, 983\u2013996.","DOI":"10.1007\/s00417-019-04251-z"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Bertolani, Y., Rigo-Quera, J., S\u00e1nchez-Vela, L., Pujol-Carreras, O., Amilburu, M., Dou, A., and Castany, M. (2025). Efficacy and Safety of Ab Externo Open Conjunctiva XEN\u00ae 63 \u039cm Implantation with a 30G Needle Scleral Tract in Primary Open-Angle Glaucoma. J. Clin. Med., 14.","DOI":"10.3390\/jcm14093195"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"100058","DOI":"10.1016\/j.ajoint.2024.100058","article-title":"State of the Art, Advantages and Drawbacks of XEN 63 Gel Stent in Glaucoma Surgery","volume":"1","author":"Gambini","year":"2024","journal-title":"AJO Int."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Bertolani, Y., Rigo-Quera, J., S\u00e1nchez-Vela, L., Pujol-Carreras, O., Amilburu, M., Dou, A., and Castany, M. (2025). Efficacy and Safety of Open-Conjunctiva Ab Externo 63 \u039cm vs. 45 \u039cm XEN\u00ae Gel Stent in Glaucoma Surgery: One-Year Follow-Up. J. Clin. Med., 14.","DOI":"10.3390\/jcm14103545"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Evers, C., B\u00f6hringer, D., Kallee, S., Keye, P., Philippin, H., Piotrowski, T., Reinhard, T., and L\u00fcbke, J. (2023). XEN\u00ae-63 Compared to XEN\u00ae-45 Gel Stents to Reduce Intraocular Pressure in Glaucoma. J. Clin. Med., 12.","DOI":"10.20944\/preprints202306.0527.v1"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1016\/j.ogla.2023.05.001","article-title":"Intermediate Outcomes of the Novel 63-\u039cm Gelatin Microstent versus the Conventional 45-\u039cm Gelatin Microstent","volume":"6","author":"Hussein","year":"2023","journal-title":"Ophthalmol. Glaucoma"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"8344","DOI":"10.1038\/s41598-025-92879-9","article-title":"Risk Factors and Protective Strategies for Hypotony Following Preserflo Microshunt Implantation","volume":"15","author":"Mieno","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Steiner, S., Resch, H., Kiss, B., and Vass, C. (2024). PRESERFLOTM Microshunt: 1-Year Results of a 25-Gauge vs. 27-Gauge Needle Tract. J. Clin. Med., 13.","DOI":"10.3390\/jcm13071979"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.ogla.2025.03.003","article-title":"Comparative Study of Early Safety and Effectiveness Outcomes of the PreserFlo MicroShunt with and without an Intraluminal Suture Stent","volume":"8","author":"Chami","year":"2025","journal-title":"Ophthalmol. Glaucoma"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Lupardi, E., Laffi, G.L., Moramarco, A., Barboni, P., and Fontana, L. (2023). Systematic Preserflo MicroShunt Intraluminal Stenting for Hypotony Prevention in Highly Myopic Patients: A Comparative Study. J. Clin. 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