title: A stepwise approach for peroral endoscopic myotomy for treating achalasia: from animal models to patients.
abstract: OBJECTIVE
  Peroral endoscopic myotomy (POEM) was initially developed for the treatment of achalasia. This study aimed to investigate the feasibility and safety of a stepwise approach for POEM in the management of achalasia.
  
  
  METHODS
  A total of five ex-vivo porcine esophagus-stomach training models were created and POEM was performed. Then, 25 patients with achalasia were treated similarly. The Eckardt score, barium esophagrams, and high-resolution manometry were used to evaluate its efficacy.
  
  
  RESULTS
  POEM procedures were completed in five stomach-esophagus models, with perforations in the initial three and success in the last two. A total of 25 achalasia patients (13 males, 12 females) with achalasia successfully underwent POEM. The mean operation time was 72.0 min (range, 45-180 min). There were two complications--one case each of severe bleeding and pneumothorax--that were both treated successfully. During the follow-up period, the median Eckardt score decreased dramatically from 8 to 1 (p = 0.000). The lower basal esophageal sphincter pressure decreased markedly (41.3 ± 12.6 vs. 11.3 ± 4.3 mmHg, p = 0.000), as well as the 4-s integrated relaxation pressure (37.1 ± 12.6 vs. 7.1 ± 2.4 mmHg, p = 0.000). Additionally, the maximum esophagus width was significantly reduced (mean reduced width: 1.6 ± 1.1 cm, p = 0.000).
  
  
  CONCLUSIONS
  The ex-vivo porcine esophagus-stomach can be used as a simple and cheap training model that mimics the POEM procedure. POEM is a safe and effective therapy for achalasia patients.
authors: Department of Gastroenterology, Nanfang Hospital, Southern Medical University , Guangzhou , China.
authors: Yutang
authors: Y
authors: Ren
authors: Xiaowei
authors: X
authors: Tang
authors: Fachao
authors: F
authors: Zhi
authors: Side
authors: S
authors: Liu
authors: Jianuan
authors: J
authors: Wu
authors: Yang
authors: Y
authors: Peng
authors: Bo
authors: B
authors: Jiang
authors: Wei
authors: W
authors: Gong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D004931:Esophageal Achalasia / Q000601:surgery*; D049630:Esophageal Sphincter, Lower / Q000601:surgery*; D004945:Esophagoscopy / Q000379:methods*; D005260:Female; D006470:Hemorrhage / Q000628:therapy; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D023421:Models, Animal; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D061646:Operative Time; D011030:Pneumothorax / Q000628:therapy; D011183:Postoperative Complications / Q000628:therapy*; D013552:Swine; D016896:Treatment Outcome; D055815:Young Adult
keywords: achalasia; animal model; peroral endoscopic myotomy