title: Gastric wall elasticity assessed by dynamic holographic endoscopy: ex vivo investigations in the porcine stomach.
abstract: BACKGROUND
  Holographic interferometry is based on the superimposition of the holograms of different motional states of an object on a single holographic storage medium. It has been used to detect structural changes in prosthetic heart valves. The combination of holographic interferometry and endoscopic imaging were applied to assess disturbances of porcine stomach wall elasticity.
  
  
  METHODS
  By connecting an electronic speckle pattern interferometry (ESPI) camera system (light source: continuous wave argon-ion laser, lambda = 514.5 nm) to different types of endoscopes, ex vivo experiments were performed on porcine stomachs to detect areas characterized by altered tissue elasticity. With linkage of the endoscopic ESPI camera complex to a fast image processing system, the method of double pulse exposure image subtraction was applied at a video frame rate of 12.5 Hz.
  
  
  RESULTS
  The speckle correlation patterns resulting from gentle gastric wall deformation were analyzed in a series of experiments in 16 porcine stomachs. Interferograms of gastric wall areas without structural abnormalities exhibited concentric fringes, whereas fringe patterns corresponding to areas of reduced tissue elasticity were characterized by parallel lines.
  
  
  CONCLUSIONS
  Applying the nondestructive method of dynamic holographic endoscopy, abnormalities of the gastric wall leading to diminished tissue elasticity can be distinguished reliably from surrounding healthy tissue.
authors.affiliation: Department of Medicine B, University of Muenster, Albert-Schweitzer-Strasse 33, D-48 129 Muenster, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Avenhaus
authors.forename: B
authors.initials: B
authors.lastname: Kemper
authors.forename: G
authors.initials: G
authors.lastname: von Bally
authors.forename: W
authors.initials: W
authors.lastname: Domschke
mesh_terms: D000818:Animals; D004548:Elasticity; D005773:Gastroscopy; D006696:Holography; D007368:Interferometry; D010535:Laparoscopy / Q000379:methods*; D013270:Stomach / Q000502:physiology*; D013552:Swine