Canaloplasty ab interno (AbiC) – 2-Year-Results of a Novel Minimally Invasive Glaucoma Surgery (MIGS) Technique

Abstract

Purpose The aim of this study is to evaluate the long-term efficacy of a novel minimally invasive glaucoma surgery technique (MIGS), Ab interno Canaloplasty (AbiC).

Material and Methods For this retrospective cohort study, we analysed the data of 25 eyes of 23 patients with open angle glaucoma who underwent an AbiC (6 eyes) or in case of an additional cataract, a combined cataract-AbiC procedure (“phacocanaloplasty ab interno”, 19 eyes), respectively. Postoperatively, we investigated the intraocular pressure (IOP) and the number of still required IOP-lowering medication, as well as surgery-related complications.

Results Overall, the mean baseline IOP of 20.24 mmHg ± 5.92 (n = 25) was reduced to 10.64 mmHg ± 2.77 (n = 25, p < 0.001), 12.55 mmHg ± 3.33 (n = 22, p < 0.001) and 13.67 mmHg ± 2.15 (n = 21, p < 0.001) at 1 day, 1 year and 2 year follow-up visit, respectively. Compared to baseline, this implies a reduction in IOP of 47.4, 37.9 and 32.5%. An average glaucoma medication usage of 1.92 ± 1.04 was registered at baseline visit and was reduced to 0,05 ± 0,23 after 2 years of follow-up. 80% of patients were off medication. In 5 eyes (20%) further antiglaucomatous eye drops or surgical treatment were administered. The only surgical complications were hyphema in 5 eyes (20%) and a localized peripheral detachment of the Descemetʼs membrane in one eye (4%) with no late sequelae.

Conclusion AbiC performed independently or combined with cataract surgery seems to be a safe and effective MIGS-technique with good long-term regulation of IOP and low risk profile.

Key words

MIGS - canaloplasty ab interno - canaloplasty - iTrack

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