Counter mucosal incision with Zenker's peroral endoscopic myotomy: an innovative approach for mucosal decompression in Zenker's diverticulum and mucosal webs.

Background And Aims: Zenker's diverticulum (ZD) is a pouch of the mucosa arising from the Killian triangle. Any size of symptomatic ZD or medium to large (2-3 cm or more) ZD needs intervention. Zenker's peroral endoscopic myotomy (Z-POEM) is the ideal first-line therapy for making the reliable myotomy. We aimed to demonstrate the latest Z-POEM techniques and counter mucosal incision (CMI) for a patient with larger-sized ZD and pre-existing esophageal mucosal webs near ZD.

Methods: The CMI technique recently was developed by our hospital for antireflux intervention. It is a novel tension-relief technique of the mucosal plasty for enhancing closure stability. This time we performed esophageal mucosal incision on the opposite side of the Z-POEM defect closure part to relieve the mucosal tension and alleviate a postoperative stricture resulting from the tight clip closure in the background of the stiff surrounding mucosa and webs near the ZD.

Results: We obtained complete eradication of ZD pouch without creating a stricture.

Conclusions: CMI is the ideal approach for preventing a stricture related to the use of tight clip closure of the Z-POEM for a larger-sized ZD with a background of the surrounding mucosal webs.