{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T19:08:18Z","timestamp":1781032098864,"version":"3.54.1"},"reference-count":24,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,6,21]],"date-time":"2025-06-21T00:00:00Z","timestamp":1750464000000},"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: This study evaluated the efficacy and safety of the ab externo open-conjunctiva (AEO) approach with adjunctive Ologen collagen matrix (OCM) compared to ab interno closed-conjunctiva (AIC) techniques for XEN45 gel stent implantation in patients with refractory open-angle glaucoma. The goal was to determine whether the AEO with OCM approach offers advantages in intraocular pressure (IOP) control and postoperative outcomes. Methods: A retrospective, comparative case series was conducted on 76 eyes from 76 patients with open-angle glaucoma who underwent XEN45 implantation between 2017 and 2022 at a single tertiary center. The patients were divided into Group 1 (AEO with OCM, n = 47) and Group 2 (AIC, n = 29). Postoperative IOP, the number of glaucoma medications, surgical complications, bleb revisions, and failure rates were recorded over 12 months. The AEO technique, supported by OCM, was assessed for its potential to reduce postoperative fibrosis and improve long-term outcomes. Results: Both groups experienced significant IOP reductions over time compared to baseline. However, Group 1 had superior outcomes, requiring fewer glaucoma medications postoperatively (p &lt; 0.05), and demonstrated lower rates of complications (10.6% vs. 31.0%, p = 0.026) and bleb revisions (8.5% vs. 34.5%, p = 0.005). Kaplan\u2013Meier survival analysis showed significantly greater cumulative surgical success in Group 1 compared to Group 2 (p &lt; 0.001). Conclusions: The AEO with OCM approach to XEN45 implantation may provide improved safety and efficacy compared to the AIC approach. It appears to be beneficial in minimizing postoperative fibrosis, reducing the medication burden, and lowering complication and failure rates. Prospective randomized trials are needed to validate these findings.<\/jats:p>","DOI":"10.3390\/jcm14134426","type":"journal-article","created":{"date-parts":[[2025,6,23]],"date-time":"2025-06-23T07:42:34Z","timestamp":1750664554000},"page":"4426","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Comparison of XEN45 Gel Stent Outcomes in Glaucoma: Ab Externo Open-Conjunctiva Approach with Ologen vs. Ab Interno Closed-Conjunctiva Approach"],"prefix":"10.3390","volume":"14","author":[{"given":"Sean J.","family":"Jin","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, San Antonio Military Medical Center, San Antonio, TX 78234, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4494-6418","authenticated-orcid":false,"given":"Sharon Y.","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Medicine, Uniformed Services University, Bethesda, MD 20814, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jared","family":"Tallo","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Naval Medical Center San Diego, San Diego, CA 92134, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harkaran S.","family":"Rana","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Walter Reed National Military Medical Center, Bethesda, MD 20814, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sorana","family":"Raiciulescu","sequence":"additional","affiliation":[{"name":"Department of Preventive Medicine and Biostatistics, Uniformed Services University, Bethesda, MD 20814, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Morohunranti O.","family":"Oguntoye-Ouma","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Walter Reed National Military Medical Center, Bethesda, MD 20814, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Won I.","family":"Kim","sequence":"additional","affiliation":[{"name":"Eye Doctors of Washington, Chevy Chase, MD 20815, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1136\/bjo.2005.081224","article-title":"The number of people with glaucoma worldwide in 2010 and 2020","volume":"90","author":"Quigley","year":"2006","journal-title":"Br. J. Ophthalmol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2491","DOI":"10.1167\/iovs.12-9483l","article-title":"Advances in glaucoma treatment and management: Surgery","volume":"53","author":"Coleman","year":"2012","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_3","first-page":"e27834","article-title":"Trabeculectomy: Does it have a future?","volume":"14","author":"Rao","year":"2022","journal-title":"Cureus"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1097\/IIO.0000000000000231","article-title":"Trabeculectomy: A brief history and review of current trends","volume":"58","author":"Koike","year":"2018","journal-title":"Int. Ophthalmol. Clin."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Buffault, J., Graber, M., Bensmail, D., Bluwol, \u00c9., Jeanteur, M.-N., Abitbol, O., Benhatchi, N., Sauvan, L., and Lachkar, Y. (2020). Efficacy and safety at 6 months of the XEN implant for the management of open angle glaucoma. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-61319-1"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"5457246","DOI":"10.1155\/2017\/5457246","article-title":"XEN glaucoma implant with mitomycin C 1-year follow-up: Result and complications","volume":"2017","author":"Galal","year":"2017","journal-title":"J. Ophthalmol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.ajo.2017.07.023","article-title":"Performance and safety of a new ab interno gelatin stent in refractory glaucoma at 12 months","volume":"183","author":"Grover","year":"2017","journal-title":"Am. J. Ophthalmol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1579","DOI":"10.1016\/j.ophtha.2017.05.004","article-title":"Efficacy, safety, and risk factors for failure of standalone ab interno gelatin microstent implantation versus standalone trabeculectomy","volume":"124","author":"Schlenker","year":"2017","journal-title":"Ophthalmology"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"772","DOI":"10.1080\/08820538.2021.1903513","article-title":"Microinvasive glaucoma surgery: An evidence-based review","volume":"36","author":"Birnbaum","year":"2021","journal-title":"Semin. Ophthalmol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"100947","DOI":"10.1016\/j.ajoc.2020.100947","article-title":"Effective treatment of a normal-tension glaucoma patient with bilateral ab externo XEN Gel Stent implantation","volume":"20","author":"Harris","year":"2020","journal-title":"Am. J. Ophthalmol. Case Rep."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1167\/tvst.8.3.58","article-title":"The implications of an ab interno versus ab externo surgical approach on outflow resistance of a subconjunctival drainage device for intraocular pressure control","volume":"8","author":"Lee","year":"2019","journal-title":"Transl. Vis. Sci. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2187","DOI":"10.2147\/OPTH.S354038","article-title":"Comparison of clinical outcomes following gel stent implantation via ab-externo and ab-interno approaches in patients with refractory glaucoma","volume":"16","author":"Gallardo","year":"2022","journal-title":"Clin. Ophthalmol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2361","DOI":"10.2147\/OPTH.S265695","article-title":"Surgical approaches for implanting xen gel stent without conjunctival dissection","volume":"14","author":"Vera","year":"2020","journal-title":"Clin. Ophthalmol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"e71","DOI":"10.1097\/IJG.0000000000002208","article-title":"Short-term Outcomes of Xen 45 Gel Stent ab Interno Versus ab Externo Transconjunctival Approaches","volume":"32","author":"Yuan","year":"2023","journal-title":"J. Glaucoma"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1097\/IJG.0000000000002320","article-title":"Comparing Outcomes of 45 Xen Implantation Ab Interno With Closed Conjunctiva to Ab Externo With Open Conjunctiva Approaches","volume":"33","author":"Ingram","year":"2024","journal-title":"J. Glaucoma"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"299","DOI":"10.2147\/OPTH.S292007","article-title":"Comparison of safety and efficacy between ab interno and ab externo approaches to XEN gel stent placement","volume":"15","author":"Tan","year":"2021","journal-title":"Clin. Ophthalmol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5310","DOI":"10.1167\/iovs.06-0378","article-title":"Control of filtering bleb structure through tissue bioengineering: An animal model","volume":"47","author":"Chen","year":"2006","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1007\/s00417-007-0744-9","article-title":"Tissue bioengineering for surgical bleb defects: An animal study","volume":"246","author":"Hsu","year":"2008","journal-title":"Graefe\u2019s Arch. Clin. Exp. Ophthalmol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1111\/ceo.13799","article-title":"Efficacy of the Ologen collagen matrix in combination with the XEN gel stent implantation in the treatment of open-angle glaucoma: A case-control study","volume":"48","author":"Anton","year":"2020","journal-title":"Clin. Exp. Ophthalmol."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Park, J., Shin, J.W., and Sung, K.R. (2022). Comparison of surgical outcomes with and without Ologen collagen matrix augmentation during XEN gel stent implantation. BMC Ophthalmol., 22.","DOI":"10.1186\/s12886-022-02668-5"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1016\/j.ogla.2022.07.002","article-title":"Clinical outcomes of ab interno placement versus ab externo placement of XEN45 gel stents","volume":"6","author":"Ruda","year":"2023","journal-title":"Ophthalmol. Glaucoma"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1016\/j.ogla.2020.12.003","article-title":"Comparison of clinical outcomes with open versus closed conjunctiva implantation of the XEN45 gel stent","volume":"4","author":"Do","year":"2021","journal-title":"Ophthalmol. Glaucoma"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"He, M., Wang, W., Zhang, X., and Huang, W. (2014). Ologen implant versus mitomycin C for trabeculectomy: A systematic review and meta-analysis. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0085782"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Oddone, F., Roberti, G., Giammaria, S., Posarelli, C., Mastropasqua, L., Agnifili, L., Micelli Ferrari, T., Pace, V., Sacchi, M., and Altafini, R. (2024). Italian XEN-Glaucoma Treatment Registry (XEN-GTR): Effectiveness and Safety at 36 Months of XEN45 Implant. J. Clin. Med., 13.","DOI":"10.3390\/jcm13237370"}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/14\/13\/4426\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:56:27Z","timestamp":1760032587000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/14\/13\/4426"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,21]]},"references-count":24,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2025,7]]}},"alternative-id":["jcm14134426"],"URL":"https:\/\/doi.org\/10.3390\/jcm14134426","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,6,21]]}}}