Efficacy of two trabecular micro-bypass stents combined with topical travoprost in open-angle glaucoma not controlled on two preoperative medications: 3-year follow-up

David F Chang,1 Eric D Donnenfeld,2 L Jay Katz,3 Lilit Voskanyan,4 Iqbal Ike K Ahmed,5 Thomas W Samuelson,6 Jane Ellen Giamporcaro,7 Dana M Hornbeak,7 Kerry D Solomon8 1Altos Eye Physicians, Los Altos, CA, 2Ophthalmic Consultants of Long Island, Rockville Centre, NY, 3Department of Ophthalmology, Wills Eye Hospital, Jefferson Medical College, Philadelphia, PA, USA; 4S.V. Malayan Ophthalmology Centre, Yerevan, Armenia; 5Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada; 6Minnesota Eye Consultants, Minneapolis, MN, 7Glaukos Corporation, San Clemente, CA, 8Carolina Eyecare Physicians, Mount Pleasant, SC, USA Purpose: To evaluate the long-term intraocular pressure (IOP)-lowering effect and safety parameters following treatment with two trabecular micro-bypass stents and topical prostaglandin in phakic eyes with open-angle glaucoma (OAG) not controlled on two preoperative medications. Methods: This prospective, single-arm, unmasked study enrolled 39 qualified phakic eyes with OAG not controlled on 2 medications, preoperative medicated IOP of 18–30 mmHg, and IOP following medication washout of 22–38 mmHg. Two trabecular micro-bypass stents were implanted as a standalone procedure, and travoprost was started on postoperative day 1. Evaluations included IOP, best-corrected visual acuity, medication use, fundus and slit-lamp examinations, visual field, cup:disc ratio, central corneal thickness, and ocular complications. Data through 18 months were summarized previously. Thirty-seven of the original 39 subjects have been followed for 3 years postoperatively; follow-up is continuing for 5 years. Results: At 3 years postoperative, 97% of eyes had achieved an IOP reduction of ≥20% from baseline with a reduction of 1 medication. Eighty-six percent of eyes had IOP of ≤18 mmHg with a reduction of 1 medication. Mean medicated IOP decreased to 14.0±2.6 mmHg on 1 medication versus 22.4±2.3 mmHg on 2 medications preoperatively. The mean unmedicated IOP decreased to 17.7±1.7 mmHg at 37 months from 25.3±1.9 mmHg preoperatively. Long-term postoperative adverse events included cataract surgery in 3 eyes due to cataract progression, and trabeculectomy in 1 eye due to uncontrolled IOP of 23 mmHg. No intraoperative or device-related adverse events occurred. Conclusion: Significant and sustained reduction in IOP and medications with a favorable safety profile was shown through 3 years after implantation of 2 trabecular micro-bypass stents combined with postoperative travoprost in phakic OAG eyes uncontrolled on 2 preoperative medications. These findings demonstrate the long-term performance and safety of trabecular bypass stents in combination with topical prostaglandin for OAG patients. Keywords: glaucoma, trabecular micro-bypass, MIGS, IOP, medication