A modified scleral dissection technique with suprachoroidal drainage for canaloplasty.

Purpose: A modified canaloplasty technique is described that may facilitate the surgical procedure and potentially maximizes the intraocular pressure (IOP)-lowering effect by altering both the trabecular and uveoscleral aqueous outflow.

Methods: The second deeper layer in the modified technique (about 3.5 × 4 mm, Fig. 1a, b) is not prepared in a lamellar fashion, but is cut down full-thickness to the choroid, hence opening the suprachoroidal space. Furthermore, this second deep scleral flap creates an additional aqueous outflow and drainage into the suprachoroidal space, thus possibly lowering the postoperative IOP by improving the natural uveoscleral outflow facility.

Results: Seventy-eight eyes operated with this modified technique in the last 12 months were retrospectively analysed. Mean IOP before surgery was 19.10 mmHg and patients applied 3.0 topical medications. Twelve months after surgery, the IOP was 13.5 mmHg and patients applied 1.0 topical medication; 52.6 % of patients did not use any topical therapy.

Discussion: The modified dissection canaloplasty technique potentially improves the IOP-lowering effect due to the creation of additional suprachoroidal drainage and simplifies the most complicated step of the surgery, as the scleral spur and the Schlemm's canal can be located using suprachoroidal access.