Outcomes of 360° suture trabeculotomy after unsuccessful canaloplasty

Canaloplasty is a well-established non-penetrating glaucoma surgery. Unsuccessful outcomes can be enhanced by micro-invasive 360° suture trabeculotomy (360°trabeculotomy), analyzed in this study.

This retrospective study included twenty eyes of 19 patients, mean age 59.7±17.2 years, with primary open-angle glaucoma (POWG n = 14), pseudoexfoliation glaucoma (PEX n = 3), juvenile glaucoma (n = 2) and aphakic glaucoma (n = 1), who underwent micro-invasive 360° trabeculotomy after unsuccessful (intraocular pressure (IOP) >21 mmHg under maximum glaucoma eye drop therapy (Meds)) canaloplasty. IOPs, Meds, complications and failure rates (IOP >21 mmHg at two consecutive follow-ups) were evaluated. Complete success (no Meds) and qualified success (with Meds) rates for IOP levels ≤21 mmHg and ≤ 18 mmHg at the last follow-up were evaluated.

IOPs and Meds were significantly reduced from before to 1 week (10.3±3.1 days) after 360° trabeculotomy (IOP, 28.3±6.0 mmHg to 15.8±4.5 mmHg; p < 0.001; Meds, 3.1 ± 1.2 to 1.0 ± 1.2; p < 0.001). IOPs (p = 0.37) and Meds (p = 0.33) did not decrease further from 1 week until the last follow-up (18.3 ± 8.2 months (IOP, 14.4±3.8 mmHg; Meds, 1.5±1.3)). Complete and qualified success was 25% (5/20) and 70% (14/20) for IOP ≤21 mmHg, as well as 25% (5/20) and 60% (12/20) for IOP ≤18 mmHg. Four eyes had postoperative hyphema, which resolved after a mean period of 4.0 ± 2.2 days. Five failures occurred after a mean of 40.6 ± 51.9 days after 360° trabeculotomy. All failures underwent trabeculectomy. Eyes that needed early (≤3 months post canaloplasty) 360° trabeculotomy showed higher IOPs before (p < 0.001) and lower (p = 0.03) IOPs 2 months post 360° trabeculotomy than eyes with late (>3 months) 360° trabeculotomy surgery.

360° trabeculotomy is a safe, micro-invasive, simple and successful method to enhance failed canaloplasty.