Submucosal tunnel endoscopy: Peroral endoscopic myotomy and peroral endoscopic tumor resection

Figure 2 Bilateral peroral endoscopic myotomy in advanced sigmoid (S2) type achalasia with mega esophagus and severe dysphagia in a 74-year-old male with 35-year-old history of achalasia. A: Anterior myotomy. Circular muscle is too thick; B: Closure of the mucosal entry by clips after anterior POEM; C and D: Posterior myotomy at the opposite site. We recognize the mucosal flap and myotomy site; E: Esophagogram after redo-posterior POEM showed sigmoid and dilated esophagus but satisfactory passage of contrast; F: Open EGJ at retroversion. POEM: Peroral endoscopic myotomy; EGJ: Esophagogastric junction.