POEM is performed by using a conventional endoscopic knife.

1. After submucosal injection, an initial 2-cm mucosal incision is made by a knife in the posterior esophageal wall.
2. A submucosal tunnel from the esophagus to the gastric cardia is created using a knife.
3. Full-thickness myotomy is performed and extended 2-3 cm beyond the esophagogastric junction (EGJ) using a knife.
4. The mucosal incision is closed with endoclips.

Procedure time is measured from the start of submucosal injection until mucosal entry closure.

Pain related to POEM procedure requiring the use of tramadol pain medication.

The Eckardt score assesses the severity of achalasia symptoms by combining the sum of symptom frequency scores for dysphagia, regurgitation, and chest pain and a weight loss score. Each component can be graded from 0 to 3 points. The total range is 0 to 12, with higher scores indicating more severe symptoms (Eckardt AJ et al, Nat Rev Gastroenterol Hepatol 2011).

Manometry parameters include lower esophageal sphincter (LES) pressure and integrated relaxation pressure (IRP) on high resolution manometry.

The GerdQ has been developed as a tool to facilitate the symptom-based diagnosis of GERD. Scores ranging from 0 to 3 were applied for the four positive predictors (heartburn, regurgitation, sleep disturbance due to reflux symptoms and use of over-the-counter medications for reflux symptoms) and from 3 to 0 for two negative predictors (epigastric pain and nausea). The GerdQ score was calculated as the sum of these scores, giving a total score ranging from 0 to 18. A total GerdQ score >7 is considered indicative of significant GERD symptoms (Jones R et al, Aliment Pharmacol Ther 2009).

The severity of reflux esophagitis is graded according to the Los Angeles classification (Armstrong D et al, Gastroenterology 1996).