Posters

5 year follow-up outcomes of a prospective study of two trabecular micro-bypass stents vs prostaglandin in newly diagnosed open-angle glaucoma

Poster Details

First Author: S.Vold USA

Co Author(s):                        

Abstract Details

Purpose:

The iStent® is intended to create a bypass through the trabecular meshwork to Schlemm’s canal to improve aqueous outflow through the natural physiologic pathway. This study evaluated long-term safety and performance of two micro-bypass stents (iStent®) as an initial standalone procedure compared to initial medical therapy (travoprost) in subjects with newly diagnosed OAG.

Setting:

All surgeries and follow-up visits were completed at the S.V. Malayan Ophthalmological Center in Yerevan, Armenia.

Methods:

This 5-year prospective, randomized, unmasked study enrolled subjects with OAG naïve to medical and surgical treatment. Enrolled eyes were phakic with normal angle anatomy having IOP 21-40 mmHg and a vertical C/D ratio ≤0.9. One-hundred one subjects were randomized (1:1) to implantation of two iStent devices (n=54) or topical travoprost QD (n=47). Ninety of the 101 subjects completed 5-year follow-ups. Efficacy outcomes included IOP reduction and use of additional medications following initial treatment. Safety measures included adverse events, BCVA, visual field, gonioscopy, corneal thickness and optic nerve assessments

Results:

Mean pretreatment IOP was 25.5 ± 2.5 mmHg (iStent group) and 25.1 ± 4.6 mmHg (travoprost group). Mean IOP for scheduled visits through 5 years ranged between 13.5 to 16.5 mmHg in both groups with 12/35 eyes in the iStent group required post-treatment medication compared to 18/32 eyes in the travoprost group. IOP ≤18 mmHg without additional medical therapy was reported in 77% of iStent eyes versus 53% of travoprost eyes at 5 years. An excellent safety profile was observed in both groups. The most common event occurring over the 5-year period was progression of pre-existing cataract (both groups, ~30%).

Conclusions:

In this study, both groups showed long-term substantial IOP reduction with favorable safety over a 5-year period. More subjects in the 2 iStent treatment group achieved IOP ≤18 mmHg without additional medical therapy and remained medication-free through 5 years as compared to initial topical prostaglandin therapy. The data from this prospective study, comparing 2 iStent devices to topical prostaglandin therapy, supports the efficacy of multiple iStent implantations performed as an initial standalone procedure as an initial therapy for patients newly diagnosed with OAG.

Financial Disclosure:

None