Risk of circumferential viscodilation in viscocanalostomy.

Rękas et al. 1report on a new technique for lavage of predescemetic hemorrhage and blood clot removal after canalostomy assisted using the iTrack microcatheter (Ellex, Inc.). We have been using canaloplasty since 2006. In the beginning we used a 6-0 polypropylene suture for the catheterization of Schlemm canal and placing of a tension suture. This technique was adapted from 360-degree trabeculotomy for congenital glaucoma. Since 2008, we used a flexible microcatheter (iTrack) to perform viscocanaloplasty. Although this catheter made catheterization of Schlemm canal much easier, we realized that injecting a high-viscosity ophthalmic viscosurgical device into Schlemm canal might cause Descemet membrane detachment, rupture of the trabecular meshwork with cheese-wiring of the polypropylene suture, or opening of the suprachoroidal space and detachment of the ciliary body. All this can happen with the best surgical practice because viscodilation cannot be sufficiently controlled. Even the intraoperative use of ultrasound biomicroscopy or optical coherence tomography could not prevent this complication in our hands. Circumferential viscodilation makes the procedure less controlled and reproducible. After having multiple eyes with Descemet membrane detachment, we stopped using iTrack-assisted viscocanaloplasty and continued to perform canaloplasty while paying more attention to the proper tensioning. In recent years, we