Peroral endoscopic myotomy (POEM) is the application of esophageal myotomy to the concept of natural orifice transluminal surgery (NOTES) by utilizing a submucosal tunneling method. Since the first case of POEM was performed for treating achalasia in Japan in 2008, this procedure is being more widely used by many skillful endosopists all over the world. Currently, POEM is a spotlighted, emerging treatment option for achalasia, and the indications for POEM are expanding to include long-standing, sigmoid shaped esophagus in achalasia, even previously failed endoscopic treatment or surgical myotomy, and other spastic esophageal motility disorders. Accumulating data about POEM demonstrate excellent short-term outcomes with minimal risk of major adverse events, and some existing long-term data show the efficacy of POEM to be long lasting. In this review article, we review the technical details and clinical outcomes of POEM, and discuss some considerations of POEM in special situations.
Colon, Sigmoid ; Esophageal Achalasia* ; Esophageal Motility Disorders* ; Esophagus ; Japan ; Muscle Spasticity

Achalasia is an esophageal motility disorder characterized by incomplete relaxation of the lower esophageal sphincter (LES) and aperistalsis of the esophageal body. Treatment of achalasia is aimed at decreasing the resting pressure in the LES. Peroral endoscopic myotomy (POEM), derived from natural orifice transluminal endoscopic surgery (NOTES) and advances in endoscopic submucosal dissection (ESD), presents a novel, minimally invasive, and curative endoscopic treatment for achalasia. POEM involves an esophageal mucosal incision followed by creation of a submucosal tunnel crossing the esophagogastric junction and myotomy before closure of the mucosal incision. Although the procedure is technically demanding and requires a certain degree of skill and competency, treatment success is high (90%) with low complication rates. Since the first described POEM in humans in 2010, it has been used increasingly at centers worldwide. This article reviews available published clinical studies demonstrating POEM efficacy and safety in order to present a proposal on how to establish a dedicated POEM program and reach base proficiency for the procedure.
Esophageal Achalasia ; Esophageal Motility Disorders ; Esophageal Sphincter, Lower ; Esophagogastric Junction ; Humans ; Natural Orifice Endoscopic Surgery ; Relaxation