title: Endoscopic augmentation of the esophagogastric junction with polymethylmethacrylate: durability, safety, and efficacy after 6 months in mini-pigs.
abstract: OBJECTIVE
  Endoscopic augmentation of the esophagogastric junction (EGJ) with polymethylmethacrylate (PMMA) has been reported in an experimental short-term study. We assessed whether endoscopic augmentation of the EGJ with PMMA is durable, safe, and efficacious after 6 months in mini-pigs.
  
  
  METHODS
  Ten mini-pigs were studied under anesthesia. After a pilot study in two animals, eight mini-pigs underwent lower esophageal sphincter (LES) manometry and gastrostomy with measurement of gastric yield volume (GYV) and gastric yield pressure (GYP). Endoscopic implantation of PMMA was performed aiming for the submucosa of the EGJ. Six months later, LES manometry and GYV and GYP measurements were repeated and animals were sacrificed, followed by microscopic analyses of the EGJ.
  
  
  RESULTS
  Out of 32 implants (four per animal), 29 (91%) were identified as submucosal nodules postmortem. PMMA deposits were found at microscopic analysis in all animals and located as follows [mean (range)]: submucosa 61.5% (37.5-91%), muscularis propria 21.5% (0-58%), mucosa 11% (0-25%), and subserosa 6% (0-17%). Neither esophageal perforation nor death was observed. A significant increase in GYV (1,404 versus 905 ml; p = 0.02) and a borderline increase in GYP (8.1 versus 6.5 mmHg; p = 0.057) were detected 6 months later.
  
  
  CONCLUSIONS
  Endoscopic augmentation of the esophagogastric junction with PMMA was durable and had no complications after 6 months. However, the occurrence of implants in the subserosa requires technical refinement before use in clinical trials.
authors.affiliation: Post-Graduation Program: Sciences in Gastroenterology, School of Medicine, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2400, 2 masculine andar, Bairro Santana, Porto Alegre, RS, Brazil. FernandoFornari@gmail.com
authors.forename: Fernando
authors.initials: F
authors.lastname: Fornari
authors.forename: Carmen P F
authors.initials: CP
authors.lastname: Freitag
authors.forename: Marcos E S
authors.initials: ME
authors.lastname: Duarte
authors.forename: Cleber R P
authors.initials: CR
authors.lastname: Kruel
authors.forename: Paulo R O
authors.initials: PR
authors.lastname: Thomé
authors.forename: Paulo R S
authors.initials: PR
authors.lastname: Sanches
authors.forename: Luise
authors.initials: L
authors.lastname: Meurer
authors.forename: Carlos T Z
authors.initials: CT
authors.lastname: Cerski
authors.forename: Cesar Liberato
authors.initials: CL
authors.lastname: Petzhold
authors.forename: Sidia M
authors.initials: SM
authors.lastname: Callegari-Jacques
authors.forename: Sérgio G S
authors.initials: SG
authors.lastname: Barros
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D004943:Esophagogastric Junction / Q000601:surgery*; D004945:Esophagoscopy / Q000379:methods; D005500:Follow-Up Studies; D005764:Gastroesophageal Reflux / Q000601:surgery*; D005773:Gastroscopy / Q000379:methods; D008365:Manometry; D010865:Pilot Projects; D019904:Polymethyl Methacrylate / Q000494:pharmacology*; D011475:Prosthesis Failure; D019919:Prosthesis Implantation; D019651:Plastic Surgery Procedures / Q000379:methods*; D013552:Swine; D013556:Swine, Miniature; D013718:Tensile Strength; D016896:Treatment Outcome
chemical_list: D019904:Polymethyl Methacrylate