DEC 17, 2020
This retrospective, multicenter, single-arm study assessed the 1-year outcomes of sequential canaloplasty and trabeculotomy with the OMNI surgical system (Sight Science) in pseudophakic patients with open-angle glaucoma.
Researchers followed 48 pseudophakic patients with mild to moderate open-angle glaucoma for 12 months after standalone treatment with the OMNI system. Primary success was defined as proportion of patients with 20% or greater reduction in IOP from baseline, or IOP between 6 and 18 mm Hg and maintained or reduced medication use without secondary surgical intervention. Other effectiveness endpoints included mean IOP and number of medications at 12 months. Safety endpoints were BCVA, adverse events and secondary surgical interventions. Analysis of secondary endpoints were stratified by baseline IOP more than 18 mm Hg (group 1) versus IOP of 18 mmHg or greater (group 2).
Primary success was met by 73% of patients. Mean IOP significantly decreased in group 1 (22 to 16 mm Hg) and was maintained in group 2. Medication use declined from 1.7 to 1.3 in group 1 and from 2.0 to 1.3 in group 2. Adverse events were typical for patients undergoing angle surgery and included mild inflammation (13%), IOP spikes (6%), hyphema, corneal edema and BCVA loss (all 4%). Five patients required secondary surgical intervention.
The main limitations are the retrospective study design and small sample numbers. In addition, 10% of subjects dropped out but the trial does not account for what happened to these individuals or at what stage they dropped out—potentially introducing a bias. Another main concern is that the OMNI procedure wasn't uniform in all subjects: more patients underwent 180° viscocanalostomy rather than a 360° procedure (56% vs. 44%) and most trabeculotomies were 180° (85%). These disparities could account for the significant difference in outcomes.
Standalone MIGS options are necessary given that most MIGS are only indicated when combined with cataract surgery. This study demonstrates that the OMNI system is efficacious as a standalone option for pseudophakic patients with mild to moderate open-angle glaucoma with above goal IOP. As the authors note, treatment goals differ depending on the preoperative IOP. Further prospective studies that standardize the OMNI technique and use a protocol for medications are needed to determine if this approach would be meaningful for just medication reduction in patient with IOPs that are at goal.