Long-term Outcomes from the HORIZON Randomized Trial for a Schlemm’s Canal Microstent in Combination Cataract and Glaucoma Surgery

Five-Year Visual Field Outcomes of the HORIZON Trial

“…Minimally Invasive Glaucoma Surgery (MIGS) devices that can be implanted into Schlemm's canal in conjunction with CS, such as the Hydrus Microstent (HMS, Alcon, Fort Worth, TX), have been tested in prospective multicenter randomized clinical trials, demonstrating significantly greater reduction in medication use and IOP compared to CS alone, with similar safety 10,12,15,16 , providing cataract patients with an opportunity for combined surgical treatment of glaucoma without the risks of filtration surgery 17 . Recent results from the HORIZON trial, a prospective randomized multicenter study, confirmed long term effectiveness in controlling IOP and safety of the HMS at 36 11 and 60 months 18 . This contrasts with other MIGS devices for which long term data were either not available, showed shorter duration of efficacy 19 or exhibited serious long term side effects, such as corneal endothelial cell loss 20 .…”

“…The current study evaluated data from HORIZON, a prospective, multicenter, single masked, randomized, controlled clinical trial comparing CS and CS-HMS 11,16,18 , involving 38 centers (26 in the United States and 12 international) with up to 5 year of follow-up. The protocol was approved at all centers by local governing institutional review boards, ethics committees and national regulatory agencies where needed, and conducted according to the principles in the Declaration of Helsinki and complied with the Health Insurance Portability and Accountability Act and local patient privacy protection regulations.…”

“…Details of recruitment and post-operative protocols were previously described in detail 11,16,18 . Briefly, patients with age-related cataract and a diagnosis of mild to moderate POAG using 1 to 4 topical hypotensive medications were prospectively enrolled.…”

“…Visual field assessment VF examinations were performed at preoperative baseline and 6, 12, 24, 36, 48 and 60 months after surgery using a Humphrey Field Analyzer (HFA, Zeiss Meditec, Dublin, CA, USA), 24-2 pattern, SITA-Standard strategy. Additional VF tests were performed if worsening in MD of 2.5 dB or more from the preoperative baseline was observed, as this was defined in the protocol as an adverse event 11,18 and required confirmation with two additional reliable VFs.…”

Microinvasive glaucoma surgeries: critical summary of clinical trial data with and without phacoemulsification

“…Five-year results from the HORIZON trial investigating safety and efficacy of the Hydrus microstent were recently published as follow-up to 2-year results reported in the respective pivotal trial [10 ▪▪ ]. However, unlike the 2-year data, a repeat medication washout was not performed at final follow-up.…”