Learning Curve for Gastric Endoscopic Submucosal Dissection

ESD was performed under conscious sedation. For sedation, midazolam and/or propofol were administered intravenously, with cardiorespiratory monitoring. Initially, indigo carmine dye was sprayed onto the tumor to clarify the margin. Then, markings were made 10 mm outside the tumor margin using argon plasma coagulation. After marking, a mixture of sodium hyaluronate with indigo carmine and epinephrine was injected into the submucosa outside the marking dots. Circumferential mucosal incision and submucosal dissection were performed using a Dual and/or IT knife. During the procedure, immediate bleeding was treated by Coagrasper. After ESD, chest and abdominal plain radiography were performed routinely for detection of gastric perforation.