Study Summary
The HORIZON trial, which compared cataract surgery alone with cataract surgery in conjunction with implantation of the Hydrus Microstent (Ivantis, Inc; Irvine, California), concluded at 3 years that the combination surgery was more effective at intraocular pressure (IOP) lowering. Furthermore, the study concluded that placement of the Microstent reduced the mean number of medications needed as well as the risk for further incisional surgeries over 3 years.
A total of 556 eyes were included, with eyes randomly assigned 2:1 to either receive the stent or not. The statistically significant findings were that 73% of patients in the Microstent group were medication free compared with 48% in the cataract surgery–alone group. Yet, the mean IOP was similar in both groups at about 17 mm Hg. More medication was required in the cataract surgery–alone group, however, with a mean of 0.8 ± 1.0, while the stent group's mean medication was 0.4 ± 0.8.
There were no procedure- or device-related adverse events or significant loss of corneal endothelial cells. Thus, the data from the HORIZON trial 3-year results suggest that combining Schlemm canal Microstent insertion with cataract surgery in patients with mild to moderate open-angle glaucoma is an effective way to lower IOP with less medication dependence while also potentially reducing the risk of requiring further incisional surgery.
