Grieshaber MC, et al. - In this prospective randomized pilot study, researchers contrasted a modified incision technique with classic scleral flap dissection for canaloplasty with canal expander in terms of effectiveness and safety. The sample consisted of 16 patients (32 eyes) with primary open-angle glaucoma, access to Schlemm's canal was created by deep lamellar dissection (scleral flap excision, group 1) or by vertical cut-down incision (group 2). Findings revealed that intra- and postoperative complications were uncommon and involved peripheral Descemet's membrane detachment, microhyphema and cannulation into the anterior chamber. In this intra-individual comparative study of ab externo canaloplasty with the canal expander, intraocular pressure (IOP) reduction in both groups was substantial and slightly higher in the group with deep scleral flap excision. Further reduction of IOP by transscleral drainage is suggested through the membrane window of Descemet and the intrascleral lake.