Ab interno canaloplasty (ABiC)—12-month results of a new minimally invasive glaucoma surgery (MIGS)

  • Anja-Maria DavidsEmail author
  • Milena Pahlitzsch
  • Alexander Boeker
  • Sibylle Winterhalter
  • Anna-Karina Maier-Wenzel
  • Matthias Klamann



The aim of this study is to assess whether the ab interno canaloplasty is a reasonable minimally invasive method to lower significantly the IOP level and number of antiglaucomatous medication over a certain period of time in adult primary open angle glaucoma (POAG).


In this retrospective cohort outcome study, 36 eyes of 28 POAG patients (mean age 74.8 ± 9.3 years) with an IOP above target pressure were included. Ab interno canaloplasty (ABiC) was performed in all subjects (MEyeTech GmbH, Alsdorf, Germany) as sole procedure in pseudophakic eyes (n = 20) or in combination with cataract surgery in phakic eyes (n = 16). The intraocular pressure (IOP) and the number of glaucoma medication were assessed preoperatively, day 1, week 6, month 3, month 6, and month 12.


IOP decreased from 19.8 ± 4.1 to 13.8 ± 3 mmHg at 12 months follow-up (n = 21, p < 0.001). The IOP reduction showed significant results at all time points (1 day p < 0.001; 6 weeks p < 0.001; 3 months p < 0.001; 6 months p = 0.001; 12 months p < 0.001). Glaucoma therapy was stabilized at 2.1 ± 1.6 number of medications after 12 months postoperatively. There was no significant difference in the number of medication at 12 months follow-up (p = 1.0). No major perioperative complications can be reported.


The ABiC effectively lowers the IOP in POAG in the short term follow-up of 12 months. A reduction of glaucoma therapy cannot be achieved and should be discussed with the patients prior to surgery.


Glaucoma Ab interno canaloplasty (ABiC) POAG MIGS 


Compliance with ethical standards

The study complied with the ethical standards of the Declaration of Helsinki and followed the regulations of the Good Clinical Practice (GCP) Guidelines.

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of OphthalmologyCharité – University Medicine BerlinBerlinGermany

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