Current status of endoscopic treatment for esophageal diverticulum based on diverticular peroral endoscopic myotomy

Figure 1 Schematic diagram. A: Zenker’s peroral endoscopic myotomy (Z-POEM) first, submucosal injection and mucosal incision are performed 1 cm-2 cm proximal to the septum, followed by the creation of a submucosal tunnel toward the septum. Then, two short tunnels are created by carefully dissecting the submucosal fibers on both sides of the esophagus, fully exposing the septum. Finally, septotomy is performed, followed by the closure of the mucosal incision; B: Peroral endoscopic septotomy (POES) submucosal injection and mucosal incision are performed to the top of the septum; C: Tunnel-free technique Z-POEM based on POES, submucosal cushions are created by injection on both sides of the septum, replacing mechanical dissection. For single tunnel technique (Z-POEM), a submucosal tunnel is created on the diverticulum side, while a submucosal cushion is chosen on the esophageal side. Z-POEM: Zenker’s peroral endoscopic myotomy; POES: Peroral endoscopic septotomy; TF: Tunnel-free.

Figure 2 The choice of myotomy. A: When a diverticulum is located at the right side (2:00-5:00 position), a posterior myotomy should be performed at the 6:00-8:00 position; B: Conversely, if the diverticulum is situated on the left side (7:00-10:00 position), an anterior myotomy is recommended at the 1:00-2:00 position. For standard peroral endoscopic myotomy, Zenker’s peroral endoscopic myotomy or peroral endoscopic septotomy can be used as the foundation as appropriate, and lower esophageal sphincter myotomy is performed within the same tunnel (at least 2 cm beyond the gastroesophageal junction).