title: Transesophageal endoscopic myotomy for achalasia: recognizing potential pitfalls before clinical application.
abstract: BACKGROUND
  Laparoscopic Heller esophagomyotomy is the standard of care for achalasia treatment. This procedure, although effective, must be performed with the patient under general anesthesia and is associated with several serious potential complications. The authors aimed to develop a method of performing transesophageal endoscopic esophagomyotomy (TEEM) that would obviate the need for both general anesthesia and external incisions while offering lower intra- and postoperative complications.
  
  
  METHODS
  The TEEM procedure was performed on eight pigs. For six of the pigs, the procedure aimed at survival. A mid-esophageal mucosal incision was performed using an endoscope, and a submucosal plane was developed. The lower esophageal sphincter (LES) muscle fibers were clearly visualized and divided. The mucosal incision was closed using fibrin sealant. After 2 weeks of survival, a gastrografin swallow study and necropsy were performed.
  
  
  RESULTS
  The TEEM procedure was performed successfully in all eight porcine models. The myotomy included the LES fibers and extended 4 to 6 cm proximally to the esophagus. The proximal gastric muscle was divided up to 1 to 2 cm. No injuries to the abdominal or mediastinal structures occurred. One pig died on postoperative day 1 due to an unrecognized pneumothorax. Two pigs had ischemic ulcers at the myotomy site. The last three pigs had an uneventful recovery. The mucosal incision site healed completely in all the survived pigs, and except for the pig with mediastinal sepsis, all ate heartily and gained weight as expected.
  
  
  CONCLUSIONS
  The TEEM procedure is technically feasible. Due to the morbidity encountered in the first three pigs, the reported technique was modified to include a slimmer endoscope, a shorter tunnel, and a partial-thickness myotomy. These changes together with an understanding of the pitfalls involved in this procedure led to successful results for the next three pigs. Nevertheless, the authors believe that TEEM is not yet ready for prime time. Perfection of the technique and development of dedicated instruments are mandatory before safe translation of this method to human patients.
authors: Department of General Surgery, Hadassah Hebrew University Medical Center, P.O. Box 12000, 91120, Jerusalem, Israel. mahmoudoski@yahoo.com
authors: Mahmoud
authors: M
authors: Abu Gazala
authors: Abed
authors: A
authors: Khalaila
authors: Noam
authors: N
authors: Shussman
authors: Samir
authors: S
authors: Abu Gazala
authors: Ram
authors: R
authors: Elazary
authors: Dalit
authors: D
authors: Amar
authors: David
authors: D
authors: Kushnir
authors: Oleg
authors: O
authors: Ponomernco
authors: Gideon
authors: G
authors: Zamir
authors: Avraham I
authors: AI
authors: Rivkind
authors: Yoav
authors: Y
authors: Mintz
mesh_terms: D000818:Animals; D004931:Esophageal Achalasia / Q000601:surgery*; D049630:Esophageal Sphincter, Lower / Q000601:surgery*; D016629:Esophagectomy / Q000379:methods*; D004945:Esophagoscopy / Q000379:methods*; D011183:Postoperative Complications / Q000517:prevention & control*; D034421:Sus scrofa; D014945:Wound Healing / Q000502:physiology