Triangle tip knife

POEM procedure is performed according to the technique described by Inoue et al [10] in 2010. Broad spectrum antibiotics (usually a cephalosporin or amoxicillin) are administered preoperatively. An upper endoscopy is performed using a high-definition endoscope (GIF-H180J; Olympus Tokyo, Japan) with carbon dioxide (CO 2 ) insufflation. The esophageal mucosa is cut on the anterior wall using an endoscopic cautery knife (Triangle-tip knife, Olympus), approximately 10-12 cm above the esophageal gastric junction (Fig. 1A). After the mucosal incision is completed, the esophageal submucosa is dissected using a spray coagulation current (VIO300D, ERBE Elektromedizin GmbH, Tubingen, Germany) (Fig. 1B). A long tunnel is created in the esophageal submucosa extending from the mucosal incision to 3 cm along the anterior gastric wall (Fig. 1C). The esophageal muscular layer is exposed and cut through the submucosal tunnel. The myotomy includes the circular bundles of the muscular layer and extends for 2-3cm up the gastric wall (Fig. 1D). At the end of the procedure, the mucosal incision is closed using endoscopic clips (EZ Clips, Olympus). Twenty-four or 48 hours after myotomy, an upper endoscopy under general anesthesia and a gastrografin esophageal study are performed to exclude mucosal tears or leaks; then patients are fed a soft diet.