Four-Year Efficacy and Safety of iTrack Ab-interno Canaloplasty as a Standalone Procedure and Combined with Cataract Surgery in Open-Angle Glaucoma

Abstract

Purpose To evaluate the long-term effectiveness of ab-interno canaloplasty (ABiC), performed with the iTrack microcatheter (Nova Eye Medical, Fremont, CA, USA), in reducing intraocular pressure (IOP) as well as the number of required glaucoma medications in patients with open-angle glaucoma (OAG).

Methods In this retrospective single-center consecutive case series, 27 eyes of 21 patients (mean age 77.3 ± 5.8 years) were treated with ABiC performed as a standalone procedure or combined with cataract surgery. Patients with uncontrolled IOP OAG or controlled IOP (≤ 18 mmHg) OAG with intolerance to medications or lack of compliance were included. Patients were followed for up to 4 years following the procedure. The iTrack microcatheter was used to perform a 360-degree circumferential intubation and viscodilation of Schlemmʼs canal. Primary efficacy endpoints included IOP and the number of glaucoma medications at 12, 24, 36, and 48 months after surgery.

Results In all eyes, mean IOP and number of glaucoma medications were significantly reduced from 19.8 ± 5.2 mmHg and 1.9 ± 1.00 at baseline to 14.6 ± 3 mmHg and 0.9 ± 0.8, respectively, at the 48-month follow-up (p < 0.001). IOP was stable from 12 months to 48 months (p > 0.005). After 48 months, 39% of the eyes required zero medications compared to 3.7% at baseline, and 72.2% of eyes required only one medication or less. Of all eyes, 77.8% recorded an IOP ≤ 17 mmHg. No serious complications were recorded.

Conclusion iTrack ABiC performed as a standalone procedure or in combination with cataract surgery significantly reduced IOP and number of medications in patients with OAG up to 4 years after the procedure.

Zusammenfassung

Zweck Ziel war die Ermittlung der Langzeitwirksamkeit der Ab-interno-Kanaloplastik (ABiC) mittels iTrack-Katheter (Nova Eye Medical, Fremont, CA, USA) in Patienten mit primärem Offenwinkelglaukom (POAG) durch die Senkung des Augeninnendrucks (IOP) und der Zahl der benötigten Glaukommedikamente.

Methoden In dieser retrospektiven, monozentrischen konsekutiven Fallserie wurden 27 Augen von 21 Patienten (Durchschnittsalter: 77,3 ± 5,8 Jahre) mit ABiC als Stand-alone-Eingriff oder in Kombination mit einer Kataraktoperation behandelt. Einbezogen wurden Patienten mit kontrolliertem IOP (≤ 18 mmHg) und unkontrolliertem IOP (> 18 mmHg). Aufgrund von Medikamentenunverträglichkeiten oder mangelnder Compliance wurde bei Patienten mit kontrolliertem IOP die ABiC zur Minimierung der erforderlichen Medikamente durchgeführt und sie wurden anschließend bis zu 4 Jahre lang beobachtet. Der iTrack-Mikrokatheter wurde zur 360°-zirkumferenziellen Intubation und Viskodilatation des Schlemm-Kanals verwendet. Primäre Wirksamkeitsendpunkte der Studie waren der IOP und die Glaukommedikamentenzahl bis 12, 24, 36 und 48 Monate nach dem Eingriff.

Ergebnisse Bei allen Augen wurden der mittlere IOP und die Glaukommedikamentenzahl signifikant von 19,8 ± 5,2 mmHg und 1,9 ± 1 zu Beginn der Studie jeweils auf 14,6 ± 3 mmHg und 0,9 ± 0,8 bei der 48-monatigen Nachuntersuchung reduziert (p < 0,001). Der IOP und die Medikamentenzahl waren von 12 bis 48 Monaten stabil (p > 0,005). Nach 48 Monaten benötigten 39% der Augen keine Medikamente, verglichen mit 3,7% zu Studienbeginn, und 72,2% der Augen benötigten nur ein Medikament oder weniger. 77,8% der Augen wiesen einen IOP ≤ 17 mmHg auf. Es wurden keine ernsthaften Komplikationen verzeichnet.

Schlussfolgerung Als Stand-alone-Eingriff oder in Kombination mit einer Kataraktoperation reduzierte die iTrack-ab-interno-Kanaloplastik signifikant den IOP und die Medikamentenzahl bei Patienten mit POAG bis zu 4 Jahre nach dem Eingriff.

Key words

intraocular pressure - ab-interno canaloplasty - MIGS - canaloplasty - minimally invasive glaucoma surgery - open-angle glaucoma

Schlüsselwörter

Augeninnendruck - Kanaloplastik ab interno - MIGS - Kanaloplastik - Offenwinkelglaukom

Publication History

Received: 29 April 2021

Accepted: 21 December 2021

Article published online:
14 April 2022

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