The FDA announced approval of the CyPass Micro-Stent System (Model 241-S). This is the second minimally invasive glaucoma surgical device (MIGS) approved for use in combination with cataract surgery. This device helps to reduce intraocular pressure (IOP) in adult patients with mild to moderate primary open-angle glaucoma (POAG).
MIGS devices are designed to facilitate fluid outflow in ways that minimize tissue trauma. They are intended to treat less severe glaucoma by lowering IOP.
The CyPass System consists of the CyPass Micro-Stent, contained within a loading device, and a stent delivery tool. The device is designed for placement in the angle of the eye, with the proximal end extending into the anterior chamber (AC), and the distal end residing in the supraciliary space. This allows outflow of fluid from the AC through the distal end into the supraciliary and suprachoroidal spaces.
(Image credit: screenshot of YouTube video posted by Ike Ahmed)
The clinical performance of the CyPass Micro-Stent system was evaluated by a study of 505 patients diagnosed with POAG. 374 patients were randomized to the CyPass Micro-stent in combination with cataract surgery, and 131 patients were randomized to cataract surgery alone. The study evaluated the percentage of patients with reduction of at least 20% in mean diurnal IOP from baseline and adverse events (AEs) for 24 months after implantation. Of the patients randomized to the stent, 72.5% achieved a significant lowering of their IOP, compared to 58.0% of patients who had cataract surgery alone.
There were no reports of patients implanted with the CyPass Micro-Stent experiencing loss of light perception, endophthalmitis, suprachoroidal hemmorrhage, diplopia, wound leak, flat anterior chamber, or bleb complications. The most serious AEs reported were rare instances of hypotony maculopathy, peripheral anterior choroidal effusion, intraocular lens (IOL) subluxation, and corneal compromise. The most common safety concerns were related to bleeding, inflammation, and damage to angle tissue (i.e., iridodialysis, larger than expected cyclodialysis cleft, ciliary body edema). Due to the small size of the CyPass Micro-Stent, some patients experienced device malposition, device movement, and tube obstruction.
