Newly Diagnosed Open-Angle or Pseudoexfoliative Glaucoma or Ocular Hypertension Randomized to 2 Trabecular Bypass Stents or Prostaglandin
Purpose
To describe results through 24 months of prospective, randomized study involving MIGS implantation of two ab interno trabecular micro-bypass stents as the sole procedure vs. prostaglandin medical therapy in eyes with open-angle glaucoma (OAG), pseudoexfoliative glaucoma (PEX) or ocular hypertension (OHT) naïve to medical and surgical therapy.
Methods
The MIGS Study Group evaluated implantation of two stents (iStent, Glaukos), as the sole procedure vs. prostaglandin in 98 qualified phakic eyes with OAG, PEX or OHT naïve to therapy. Inclusion criteria also included IOP 21 - 40 mmHg, C/D ratio ≤ 0.9, and ability to undergo follow-up through 60 months. Ocular hypotensive medication was to be added if postoperative IOP exceeds 21 mmHg, regardless of treatment group. The primary efficacy endpoint was change from screening in mean diurnal IOP (mmHg) at the Month 12 visit. Safety parameters include optic nerve evaluation, BCVA, slit-lamp assessment and incidence of adverse events evaluated through five years.
Results
Qualified eyes underwent uncomplicated implantation of two iStent devices (n=50) or prostaglandin medical therapy (n=48) and 2-year follow-up. Mean preoperative IOP was 25.7 ± 2.5 mmHg in the surgery group and 25.0 ± 4.6 mmHg in the medication group. M12 mean IOP was 13.8 ± 1.7 mmHg in the surgery group (3 subjects on medication) and 13.9 ± 1.5 mmHg in the medication group (3 subjects on an additional medication). M24 mean IOP was 13.9 ± 1.3 mmHg in the surgery group (on 0 meds) and 15.0 ± 1.4 mmHg in the medication group (3 subjects on 1 additional medication). Adverse events through two years included cataract requiring secondary surgical intervention in 1 subject per group.
Conclusion
Data through two years after iStent implantation as the sole procedure vs. medical therapy in OAG, PEX or OHT naïve to treatment showed significant postoperative decrease in IOP with a favorable safety outcome. These data suggest similar efficacy with 2 stents or 1 medication in newly diagnosed OAG, PEX or OHT.