title: Augmentation of lower esophageal sphincter pressure and gastric yield pressure after radiofrequency energy delivery to the gastroesophageal junction: a porcine model.
abstract: BACKGROUND
  An endoscopic technique that eliminates gastroesophageal reflux disease would be of benefit to patients. The endoscopic delivery of radiofrequency energy to the porcine gastroesophageal junction was investigated and its effect on lower esophageal sphincter pressure, gastric yield pressure, and histology was assessed.
  
  
  METHODS
  Twenty pigs underwent esophageal manometry and endoscopic injection of botulinum toxin (100 units) into the lower esophageal sphincter. After 1 week, animals were randomized to radiofrequency energy treatment of the gastroesophageal junction with a 4- needle catheter and thermocouple-controlled generator (n = 13) or no further intervention (control, n = 7). At 9 weeks, animals underwent esophagoscopy, manometry, gastric yield pressure determination, and sacrifice for histopathologic evaluation.
  
  
  RESULTS
  Mean lower esophageal sphincter pressure declined by 3.7 +/- 2.6 mm Hg (control, p = 0.03) vs. 0.97 +/- 5.8 mm Hg (radiofrequency, p = 0.29) after 9 weeks. Mean gastric yield pressure was 24.9 +/- 8.2 mm Hg (control), compared with 43.4 +/- 10. 7 mm Hg (radiofrequency) (p = 0.0007). Histopathologic assessment demonstrated normal mucosa, mild fibrosis, and no inflammation.
  
  
  CONCLUSIONS
  Radiofrequency energy delivery reversed much of the lower esophageal sphincter pressure reduction achieved with botulinum toxin injection and augmented gastric yield pressure by 75% compared with controls. Given the safety of radiofrequency energy delivery in this study and in other areas of medicine, human studies to assess the effect of radiofrequency energy on gastroesophageal reflux disease are warranted.
authors.affiliation: Division of Otolaryngology/Head and Neck Surgery, Stanford University Medical School, Department of Surgery, Stanford University Medical Center, CA, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Utley
authors.forename: M
authors.initials: M
authors.lastname: Kim
authors.forename: M A
authors.initials: MA
authors.lastname: Vierra
authors.forename: G
authors.initials: G
authors.lastname: Triadafilopoulos
mesh_terms: D000818:Animals; D001905:Botulinum Toxins; D017115:Catheter Ablation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D004195:Disease Models, Animal; D004943:Esophagogastric Junction / Q000473:pathology* / Q000601:surgery*; D004945:Esophagoscopy; D005260:Female; D005764:Gastroesophageal Reflux / Q000473:pathology / Q000517:prevention & control*; D008297:Male; D008365:Manometry; D009126:Muscle Relaxation; D010865:Pilot Projects; D011312:Pressure; D011897:Random Allocation; D012016:Reference Values; D012680:Sensitivity and Specificity; D013552:Swine; D016896:Treatment Outcome
chemical_list: D001905:Botulinum Toxins