Canaloplasty after failed trabeculectomy: A possible option

摘要

Canaloplasty is usually indicated for eyes that have not undergone previous filtrating surgery for glaucoma. In some cases, however, " trabeculectomy" can be targeted anterior to the angle components, thus leaving Schlemm's canal integral and untouched. In the past 4 years of performing canaloplasty in our Glaucoma Clinic in Udine, a total of 6 eyes with previous failed trabeculectomy and elevated intraocular pressure (IOP) despite maximum tolerated medical therapy underwent canaloplasty. The preoperative IOP was 32.2±9.6 mm Hg, ranging from 25 to 48 mm Hg. In this group of patients, canaloplasty could be correctly completed in 5 cases; in 1 case, however, Schlemm's canal could not be cannulated for the entire 360-degree circumference, thus surgery was converted into viscocanalostomy. Follow-up ranged between 6 and 28 months (mean, 16.7±9.3 mo). The mean IOP at 6, 12, 18, and 24 months was 17.3, 15.4, 14.7, and 16.3 mm Hg, respectively. The number of medications used before and at the 2-year follow-up was 3.2±1.2 and 2.3±0.5, respectively. Our results suggest that canaloplasty can be considered as a possible surgical option in eyes with failed trabeculectomy showing undamaged Schlemm's canal from previous filtrating surgery.