title: Peroral endoscopic myotomy for treatment of achalasia: from bench to bedside (with video).
abstract: BACKGROUND
  Peroral endoscopic myotomy (POEM) is a novel approach to performing esophageal myotomy through a long submucosal tunnel.
  
  
  OBJECTIVE
  This study aimed to investigate the feasibility and safety of POEM for treatment of achalasia.
  
  
  METHODS
  Preclinical animal study and prospective clinical study.
  
  
  METHODS
  Consecutive patients diagnosed with achalasia with high-resolution manometry.
  
  
  METHODS
  POEM was standardized for preclinical and clinical studies. After submucosal injection, a mucosal incision was made 15 cm above the gastroesophageal junction (GEJ). A long submucosal tunnel was created to extend below the GEJ. The endoscopic myotomy started 10 cm above and extended 2 cm below the GEJ. We first conducted a preclinical animal study to confirm the safety of POEM. POEM was then performed for the treatment of achalasia in humans.
  
  
  METHODS
  Relief from dysphagia assessed by the dysphagia score and Eckhardt score. High-resolution manometry and pH monitoring were performed to evaluate the posttreatment effects and esophageal acid exposure.
  
  
  RESULTS
  Seven 30-kg porcine models underwent POEM in the survival study. All of the pigs survived except 1, which sustained pneumomediastinum. POEM was performed for the treatment of achalasia in 16 patients. The mean operating time was 117.0 ± 34.1 minutes. All patients tolerated food on day 2, with a contrast study confirming no leakage. The median follow-up was 176.5 days (range 98-230 days). The postoperative basal lower esophageal sphincter pressure was significantly reduced (mean reduction, 13.9 ± 14.5 mm Hg; P = .005) and 4-second integrated relaxation pressure of the GEJ (mean reduction, 10.1 ± 7.4 mm Hg; P = .001). Of these patients, 58.3% had a normalized 4-second integrated relaxation pressure, whereas 20% had excessive esophageal acid exposure after the procedure. There was a significant improvement in quality of life 6 months after POEM measured by the Short Form-36 questionnaire.
  
  
  CONCLUSIONS
  Small sample size.
  
  
  CONCLUSIONS
  POEM is a feasible, safe, and effective treatment for achalasia.
authors.affiliation: Departments of Surgery and Medicine and Therapeutics, Institute of Digestive Disease, The Chinese University of Hong Kong, Shatin, Hong Kong. philipchiu@surgery.cuhk.edu.hk
authors.forename: Philip Wai Yan
authors.initials: PW
authors.lastname: Chiu
authors.forename: Justin Che Yuen
authors.initials: JC
authors.lastname: Wu
authors.forename: Anthony Yuen Bun
authors.initials: AY
authors.lastname: Teoh
authors.forename: Yawen
authors.initials: Y
authors.lastname: Chan
authors.forename: Simon Kin Hung
authors.initials: SK
authors.lastname: Wong
authors.forename: Shirley Yuk Wah
authors.initials: SY
authors.lastname: Liu
authors.forename: Man Yee
authors.initials: MY
authors.lastname: Yung
authors.forename: Candice C H
authors.initials: CC
authors.lastname: Lam
authors.forename: Joseph Jao Yiu
authors.initials: JJ
authors.lastname: Sung
authors.forename: Francis Ka Leung
authors.initials: FK
authors.lastname: Chan
authors.forename: James Yun Wong
authors.initials: JY
authors.lastname: Lau
authors.forename: Enders Kwok Wai
authors.initials: EK
authors.lastname: Ng
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D004931:Esophageal Achalasia / Q000601:surgery*; D004943:Esophagogastric Junction / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D009132:Muscles / Q000601:surgery; D057605:Natural Orifice Endoscopic Surgery; D011446:Prospective Studies; D013552:Swine; D016896:Treatment Outcome