Outcomes of Ab-Interno Canaloplasty and Gonioscopy-Assisted Transluminal Trabeculotomy in Eyes with Sustained...

To evaluate the long-term efficacy and safety of combined ab-interno canaloplasty (ABiC) and gonioscopy-assisted transluminal trabeculotomy (GATT) with the iTrack microcatheter in patients with sustained intraocular pressure (IOP) elevation following intravitreal anti-VEGF or steroid injections.

This was a retrospective, single-center study of patients who underwent ABiC and GATT with the iTrack microcatheter between 2017 and 2021 for secondary open-angle glaucoma or ocular hypertension following intravitreal injections. Eligible eyes had a preoperative IOP of ≥18 mmHg while on maximal tolerated medical therapy. Primary outcomes included IOP and glaucoma medication burden. Surgical success was defined using American Academy of Ophthalmology (AAO) criteria. Subgroup analyses were conducted by etiology (anti-VEGF vs steroid-induced). Kaplan-Meier analysis estimated cumulative success rates.

Thirty-four eyes from 30 patients were included, with a mean last follow-up of 15.3±9.8 months. Mean IOP was reduced by 46%, from 28.1±6.0 mmHg at baseline to 14.3±5.6 mmHg (p<0.001) at the last follow-up, while the number of medications decreased from 2.79±0.9 to 1.76±1.5 (p=0.001). Surgical success was achieved in 71% of eyes. Medication-free status was reached in 29% of eyes, compared with none at baseline, and 26% achieved IOP ≤15 mmHg without medications. Additional glaucoma procedures were needed in 11.8% of eyes. Combined ABiC and GATT remained effective in eyes receiving post-procedure intravitreal reinjections or prolonged topical steroid use. Kaplan-Meier analysis showed a survival probability above 70% at 25 months.

Combined ab-interno canaloplasty and GATT using the iTrack microcatheter is a safe surgical option for selected eyes with sustained IOP elevation following intravitreal injections. The procedure achieved meaningful reductions in IOP and medication use, including in eyes requiring continued intravitreal therapy, supporting a primary surgical effect. Careful patient selection and long-term follow-up remain essential, as a subset of eyes may require additional intervention.