Stegmann Canal Expander for canaloplasty: A novel technique

INTRODUCTION: The concept of canaloplasty is to increase aqueous egress through all structures that control the aqueous outflow, such as the trabecular meshwork, Schlemm's canal, and collector channels, by viscomodulation and by placing of a suture stent into the canal. Clinical studies show canaloplasty to be safe and efficient in lowering the intraocular pressure; however, proper knotting of the tensioning suture is technically challenging and even impossible if circumferential cannulation cannot be achieved; furthermore, protrusion of the suture stent is a potential lifelong risk. METHODS: The specific design of the Stegmann Canal Expander allows a permanent expansion of the canal and distension of the trabecular meshwork. Two expanders are implanted on either side of the surgically created ostium of Schlemm's canal to treat half of the circumferential outflow system. This article describes the technique step by step, provides the clinician with surgical pearls, and highlights the management of adverse events. RESULTS: Technically, implantation of the Stegmann Canal Expander is simple and does not require a long learning curve, compared to placing and knotting a tensioning suture. Most issues are related to the two-flap dissection technique (deep sclerectomy technique) and not to implantation of the Stegmann Canal Expander. Intraocular pressure reduction without medications to the low teens can be achieved. CONCLUSIONS: The Stegmann Canal Expander is a novel micro-device that has the potential to make canaloplasty a simplified, more controlled, and reproducible surgical procedure.