Study parameters of HRM, pH-MII and EGD.

Introduction
Achalasia is a rare neurodegenerative esophageal motility disorder characterized by incomplete lower esophageal sphincter (LES) relaxation, increased LES tone and absence of esophageal peristalsis. Achalasia requires invasive treatment in all patients. Conventional treatment options include endoscopic balloon dilation (EBD) and laparoscopic Heller’s myotomy (LHM). Recently, a less invasive endoscopic therapy has been developed; Peroral Endoscopic Myotomy (POEM). POEM integrates the theoretical advantages of both EBD and LHM (no skin incisions, less pain, short hospital stay, less blood loss and a durable myotomy). Our aim is to compare efficacy and safety of POEM vs. EBD as primary treatment for achalasia in children.
Methods and analysis
This multi-center, and center-stratified block-randomized controlled trial will assess safety and efficacy of POEM vs EBD. Primary outcome measure is the need for retreatment due to treatment failure (i.e. persisting symptoms (Eckardt score > 3) with evidence of recurrence on barium swallow and/or HRM within 12 months follow-up) as assed by a blinded end-point committee (PROBE design).
Discussion
This RCT will be the first one to evaluate which endoscopic therapy is most effective and safe for treatment of naïve pediatric patients with achalasia.