title: Peroral endoscopic myotomy for treating achalasia in an animal model: a feasibility study.
abstract: OBJECTIVE
  Laparoscopic Heller myotomy with antireflux procedure is considered to be a standard treatment for achalasia. Recently, peroral endoscopic myotomy (POEM) was developed and performed on patients with achalasia. However, there is no report on POEM use in South Korea. The aim of this study was to evaluate the technical feasibility of POEM in a porcine model.
  
  
  METHODS
  POEM was performed on two mini pigs. We performed upper endoscopy under general anesthesia. A submucosal tunnel was created and the circular muscle layer was incised using several knives. The mucosal entry was closed using resolution clips. We performed a follow-up endoscopy and sacrificed the pigs 2 weeks after the POEM. The myotomy site was evaluated grossly and histologically.
  
  
  RESULTS
  POEM was successfully performed on the two mini pigs. No injuries to any abdominal or mediastinal structures occurred. Two weeks after the POEM, the esophageal mucosa healed without any endoscopic evidence of complications. Necropsy revealed that the circular muscle layer was completely lost and replaced with fibrotic tissue.
  
  
  CONCLUSIONS
  We found that POEM is a technically feasible method which can be performed on an animal model. However, to ensure safe use on patients with achalasia, further studies on technical methods and long-term follow-up examinations are required.
authors: Department of Internal Medicine, Inha University School of Medicine, Incheon, Korea.
authors: Byoung Wook
authors: BW
authors: Bang
authors: Young Chul
authors: YC
authors: Choi
authors: Hyung Gil
authors: HG
authors: Kim
authors: Kye Sook
authors: KS
authors: Kwon
authors: Yong Woon
authors: YW
authors: Shin
authors: Don Haeng
authors: DH
authors: Lee
authors: Joon Mee
authors: JM
authors: Kim
keywords: Animal models; Endoscopy; Esophageal achalasia; Esophagus; Feasibility studies