title: Gastroesophageal junction: structure and function as assessed by using MR imaging.
abstract: OBJECTIVE
  To develop and validate magnetic resonance (MR) imaging protocols for quantitative assessment of the structural and functional properties of the gastroesophageal junction (GEJ) and to compare MR imaging detection of reflux events against concurrent manometry as a reference method.
  
  
  METHODS
  The local ethics committee approved this study, and written informed consent was obtained. Twelve healthy volunteers were examined. Three-dimensional models of the GEJ and proximal portion of the stomach were reconstructed from high-spatial-resolution anatomic MR images to assess the insertion angle of the esophagus into the stomach and proximal stomach distention before and after ingestion of a large test meal. A linear mixed-effects model was used to detect differences in the insertion angle and proximal stomach distention with respect to the respiratory cycle and gastric filling. Additionally, dynamic MR imaging at high temporal resolution was used to detect reflux events.
  
  
  RESULTS
  The esophageal insertion angle, given in units of plane angle (radians), was more acute in expiration than in inspiration (0.57 vs 0.73 radian, P = .004) but was not affected by feeding. Progressive distention of the proximal stomach was observed from baseline compared with the postprandial period (0.95 vs 0.65 radian(-1), P < .05). Eighteen reflux events detected by using MR imaging were also detected by using manometry.
  
  
  CONCLUSIONS
  MR imaging methods were developed and validated for the assessment of GEJ structure and function (a) to describe the effects of respiration and feeding on the reflux barrier and (b) to detect reflux events in real time. Anatomic and dynamic MR imaging may be useful techniques in the assessment of GEJ physiology and reflux.
authors: Institute for Biomedical Engineering, University of Zurich and Swiss Federal Institute of Technology, Zurich, Switzerland.
authors: Jelena
authors: J
authors: Curcic
authors: Mark
authors: M
authors: Fox
authors: Elad
authors: E
authors: Kaufman
authors: Zsofia
authors: Z
authors: Forras-Kaufman
authors: Geoffrey S
authors: GS
authors: Hebbard
authors: Shammodip
authors: S
authors: Roy
authors: Anupam
authors: A
authors: Pal
authors: Werner
authors: W
authors: Schwizer
authors: Michael
authors: M
authors: Fried
authors: Reto
authors: R
authors: Treier
authors: Peter
authors: P
authors: Boesiger
mesh_terms: D000328:Adult; D004943:Esophagogastric Junction / Q000033:anatomy & histology* / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008365:Manometry; D012016:Reference Values