Comparison of Superior versus Inferior Canaloplasty and Trabeculotomy Using the OMNI Surgical System

Purpose: To compare outcomes of ab-interno canaloplasty and trabeculotomy of the superior versus inferior angle.

Patients and methods: This was a prospective, non-randomized, interventional comparison study done at the Veteran Affairs Hospital in Long Beach, California. All patients underwent cataract surgery with intraocular lens implantation combined with ab-interno canaloplasty and trabeculotomy with the OMNI Surgical System (SightSciences, Menlo Park, CA, USA), either superiorly or inferiorly. Pre- and post-operative intraocular pressure using Goldmann applanation tonometry and best corrected visual acuity were obtained and compared using paired t-tests. Patients were excluded if they had any prior intraocular surgery or prior laser trabeculoplasty procedures.

Results: 38 eyes from 29 patients were analyzed. 19 eyes were included in the superior group and 19 eyes in the inferior group. Mean pre-operative IOP in the superior group was 17.6 ± 5.2 mmHg and in the inferior group was 17.6 ± 4.6 mmHg (p > 0.99). At 12 months, mean postoperative IOP for the superior group decreased 24% to 13.3 ± 2.8 mmHg while the inferior group decreased 26% to 13.1 ± 2.2 mmHg (p = 0.92). Mean preoperative medications in the superior group were 2.2 ± 1.3 and in the inferior group was 2.4 ± 1.3 (p = 0.88). At 12 months, this decreased to 1.3 ± 1.5 post-operatively in the superior group and 2.2 ± 1.6 post-operatively in the inferior group (p = 0.64).

Conclusion: There was no statistical difference in efficacy between superior versus inferior canaloplasty/trabeculotomy with OMNI. Therefore, surgeons can perform the procedure in the direction that is most comfortable for them without affecting outcomes.