A Decade-Long Outcomes of Two First-Generation Trabecular Micro-Bypass Stents with Cataract Surgery in Primary Open-Angle Glaucoma

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: A substantial body of research has explored the outcomes of the first-generation trabecular micro-bypass stents (iStent) since its FDA approval in 2012. However, most studies have primarily focused on short- to medium-term outcomes. In this study, we present the 10-year outcomes of two first-generation trabecular micro-bypass stents combined with cataract surgery, representing the longest-term study on iStent outcomes available to date.

Study Design: Longitudinal consecutive case series.

 

Methods: The study cohort comprised eyes with mild to severe primary open-angle glaucoma (POAG) that underwent the implantation of two first-generation iStents with concomitant cataract surgery at two academic ophthalmology centers and had follow-up data available for up to 10 years postoperatively. The primary outcome measure was surgical success, defined as the need for secondary glaucoma surgery due to uncontrolled intraocular pressure (IOP) or evidence of disease progression. Secondary outcome measures included postoperative changes in IOP, use of antiglaucoma medications (AGM), and safety measures.

Results: A total of 51 POAG eyes were included. The surgical success rate was 83%, with 9 eyes requiring secondary glaucoma surgery during the 10-year follow-up period. IOP decreased by 27.4%, from 19.0 ± 3.9 mmHg preoperatively to 13.8 ± 2.1 mmHg at the 10-year follow-up (p<0.001). At the 10-year mark, 88.2% of eyes achieved an IOP of ≤18 mmHg (vs. 55.6% preoperatively). Medication use significantly decreased during the first 4 years (p<0.001). However, it gradually increased thereafter, showing no statistically significant difference in subsequent years compared to preoperative levels. Safety outcomes were favorable. Retinal nerve fiber layer (RNFL) thickness remained stable throughout the follow-up. Only one eye lost >2 lines of visual acuity attributable to progression of glaucoma. In one instance, an iStent was inadvertently placed in the suprachoroidal space with no significant sequelae.

Conclusions: The implantation of two first-generation trabecular micro-bypass stents in conjunction with cataract surgery is an effective and safe treatment option for surgery-naïve POAG eyes, evidenced by significant reductions in IOP and medication usage sustained over a medium-to long-term follow-up, a reasonable surgical success rate, and favorable safety outcomes.

Presenter(s)

Presenting Author: Ali Salimi

Additional Author(s):

Harrison Watt, McGill University

Hady Saheb, McGill University

Paul Harasymowycz, University of Montreal

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