Comparison of Keratometric Change after Xen Gel Stent Implantation, Glaucoma Drainage Devices and Trabeculectomy

Theme: Glaucoma
What: Glaucoma
Part of: Glaucoma II: Surgery / Glaucome II: Chirurgical
When: 5/31/2024, 02:00 PM - 03:30 PM
Where: Room | Salle 801

Abstract

Purpose: To compare the severity of postoperative keratometric changes and surgically induced astigmatism (SIA) after Xen Gel stent implantation, glaucoma drainage device (GDD) and trabeculectomy.

Study Design: Prospective, interventional, longitudinal study.

Methods: A total of 51 eyes diagnosed with glaucoma were stratified into 3 distinct groups, based on the type of glaucoma surgery administered between November 2020 to May 2023 : Xen Gel Stent, GDD, or trabeculectomy. GDDs included Ahmed glaucoma valve (AGV) and Baerveldt glaucoma implant (BGI). Primary outcomes included quantification of SIA at 12 months postoperatively, using Scheimpflug imaging (Pentacam) and topography (OPD-scan). Secondary outcomes included changes in best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of topical medications, and complications. Differences in outcomes were compared using parametric and nonparametric tests.

Results: Groups included 19 Xen implants (37%), 21 GDDs (41%) (2 AGV, 19 BGI), and 11 trabeculectomies (22%). Average follow-up time was 49 ± 12 weeks. At final follow up, using Pentacam imaging, SIA was reduced (P>0.05) with Xen implants (0.37 ± 0.29) when compared to GDDs (0.58 ± 0.48) and trabeculectomies (0.51 ± 0.38). On topography imaging, SIA was comparable (P>0.05) in all groups at 12 months (0.51 ± 0.51 for Xen implants; 0.49 ± 0.58 for GDDs; 0.49 ± 0.29 for trabeculectomies). At 12 months, IOP was 13 ± 23 mmHg on 1.4 ± 1.4 glaucoma drops for Xen implants, 12 ± 4 mmHg on 2.4 ± 1.2 glaucoma drops for GDDs, and 11 ± 2 mmHg on 0.2 ± 0.7 glaucoma drops for trabeculectomies (P> 0.05 for IOP comparison between groups; P<0.001 for number of glaucoma drops comparison between groups). Mean change in BCVA was 0.07 ± 0.13 LogMAR for Xen implants, 0.01 ± 0.25 LogMAR for GDDs, and -0.11 ± 0.16 LogMAR for trabeculectomies (P > 0.05) at final follow up. Number of complications were comparable between groups (P>0.05).  

Conclusions: Xen implantation shows a trend towards less SIA compared to GDD implantation and trabeculectomy on Pentacam imaging. However, SIA appears comparable when assessed using topography.

Presenter(s)

Presenting Author: Kenan Bachour

Additional Author(s):

Dominique Geoffrion, Université de Montréal

Guillaume Mullie, Hôpital de la Cité-de-la-Santé

Younes Agoumi, Centre Hospitalier de l'Université de Montréal

Georges M. Durr, Centre hospitalier de l'Université de Montréal

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