title: A bioabsorbable polymer patch for the treatment of esophageal defect in a porcine model.
abstract: BACKGROUND
  Although several materials have been used to replace the esophagus, none of the materials appears to be feasible for clinical use. Our group has developed a bioabsorbable polymer that can be used to repair the defects of stomach, small intestine, biliary tract, and veins. In this study, we implanted a bioabsorbable polymer patch (BAPP) into an esophageal defect and we investigated the clinical utility of BAPP and evaluated the process of esophageal regeneration.
  
  
  METHODS
  Pigs (n = 9) underwent right thoracotomy under general anesthesia. A 4 × 2-cm oval-shaped portion of the esophageal wall was excised, and a BAPP was implanted at the excision site. Esophageal endoscopy was performed at 2 weeks after the implantation. At 4, 8, and 12 weeks after implantation, the whole esophagus was resected for gross and histological examinations of the graft sites.
  
  
  RESULTS
  Esophageal endoscopy at 2 weeks revealed a tiny ulceration at the implantation site with no stenosis. At 4 weeks, the epithelium at the graft site was similar to that of the native esophagus, but it lacked a proper muscle layer. At 8 weeks, a rough muscle layer had developed. At 12 weeks, normal mucosa and a proper muscle layer similar to that of the native wall were confirmed.
  
  
  CONCLUSIONS
  BAPP repaired the defective esophageal wall without complications, and a neo esophageal wall identical to the native esophageal wall had formed by 12 weeks after implantation. Hence, this newly designed substitute has the potential for application as a novel treatment for defective esophagus.
authors.affiliation: Department of Surgery, Gastrointestinal Center, Saitama Medical University, International Medical Center, 1397-1 Yamane, Hidaka, Saitama 350-1298, Japan. aikawama@ybb.ne.jp
authors.forename: Masayasu
authors.initials: M
authors.lastname: Aikawa
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Miyazawa
authors.forename: Kojun
authors.initials: K
authors.lastname: Okamoto
authors.forename: Katsuya
authors.initials: K
authors.lastname: Okada
authors.forename: Naoe
authors.initials: N
authors.lastname: Akimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sato
authors.forename: Isamu
authors.initials: I
authors.lastname: Koyama
authors.forename: Shigeki
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Ikada
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D004195:Disease Models, Animal; D004935:Esophageal Diseases / Q000473:pathology / Q000601:surgery*; D004945:Esophagoscopy; D004947:Esophagus / Q000473:pathology / Q000502:physiology / Q000601:surgery*; D005240:Feasibility Studies; D009092:Mucous Membrane / Q000378:metabolism; D011108:Polymers / Q000737:chemistry*; D012038:Regeneration; D013552:Swine; D013997:Time Factors; D023822:Tissue Engineering
chemical_list: D011108:Polymers