Abstract
Purpose: :
To evaluate the efficacy of the iStent Trabecular Micro-Bypass Stent (Glaukos Corp.) in patients with open angle glaucoma, refractory to previously attempted medical and surgical therapies.
Methods: :
Prospective, open-labeled, 24 month, multi-country evaluation of 45 patients with uncontrolled advanced primary open-angle glaucoma who underwent ab-interno stent implantation. The device reduces aqueous resistance by creating a long-lasting patent bypass between the anterior chamber and Schlemm’s canal. The stent is inserted through a 1.0 mm temporal clear corneal incision. Enrolled patients were required to have undergone previous conventional medical and surgical therapies that failed or were considered to have a poor prognosis for filtration surgery. Thirty patients completed 18 months; results are presented in this interim analysis. Primary end point was achievement of an IOP ≤21 mm Hg. Secondary end point was reduction in mean medication use.
Results: :
Mean preoperative IOP was 28.4 (±6.39) mm Hg at baseline and 17.9 (±3.62) mm Hg at month 18 (P=0.0001). At baseline, the mean number of medications was 2.1 (±0.94); by month 18 the mean number of medications was 1.2 (±1.18). This was statistically significant (P<0.0001). One-third of patients completing the 18-month evaluation (10 eyes) achieved an IOP ≤ 21 mm Hg with no ocular hypotensive medications. Overall, 90% of eyes reached an IOP of ≤ 21 mm Hg. The most commonly reported adverse event was trabeculectomy (n=13).
Conclusions: :
The iStent was safe and efficacious in difficult-to-treat patients who had failed on prior therapy and/or surgery or were considered poor candidates for filtering procedures. This ab-interno procedure resulted in statistically significant reductions in mean IOP and reduced reliance on medications.
Clinical Trial: :
www.clinicaltrials.gov NCT00326040
Keywords: intraocular pressure • outflow: trabecular meshwork