New Way for Ab Interno Trabeculotomy: Initial Results
Glaucoma surgeons continue to search for blebless options for safer intraocular pressure (IOP) reduction. Ab interno trabeculotomy is one of many minimally invasive techniques currently utilized. Our goal was to examine efficacy and safety of a new procedure, Trab360.
A retrospective review was performed of 26 consecutive eyes undergoing ab interno trabeculotomy using Trab360 (Sight Science). The device is a trabeculotome that advances a nylon probe into Schlemm’s canal and uses manual traction to unroof trabecular meshwork. All patients had open angles. The primary outcome measure was surgical success, defined as an IOP between 6 and 21 mmHg, with no further glaucoma surgery. Secondary outcomes included visual acuity, intraocular pressure (IOP), number of medications, and complications.
Mean follow-up time was 131.5 ± 101.6 days. Surgical success at final follow-up was 25 of 30 eyes (83%) with or without medications. Pre-operative IOP was 19.8 +/- 6.4. At final follow-up, mean IOP was 13.5 +/- 4.6. Mean number of medications pre-op was 1.1 ± 1.2. At the final visit, mean number of meds was 0.2 ± 0.5 and 19 patients (73%) required no medications. The most frequently seen complication was transient hyphema, which resolved by post-op week one in all cases.
Circumferential ab interno trabeculotomy seems as safe and effective as circumferential ab externo trabeculotomy. TRAB360, a new manual instrument for cutting trabecular meshwork tissue, facilitated a consistent ab interno trabeculotomy. More study is needed to further evaluate ab interno circumferential trabeculotomy as a minimally invasive treatment for open angle glaucoma.