title: Endoscopic Doppler optical coherence tomography in the human GI tract: initial experience.
abstract: BACKGROUND
  Expanding the current endoscopic optical coherence tomography (OCT) system with Doppler capability may augment this novel high-resolution cross-sectional imaging technique with functional blood flow information. The aim of this feasibility study was to assess the clinical feasibility of an endoscopic Doppler OCT (EDOCT) system in the human GI tract.
  
  
  METHODS
  During routine endoscopy, 22 patients were imaged by using a prototype EDOCT system, which provided color-Doppler and velocity-variance images of mucosal and submucosal blood flow at one frame per second, simultaneously with high-spatial-resolution (10-25 mum) images of tissue microstructure. The images were acquired from normal GI tract and pathologic tissues.
  
  
  METHODS
  Subsurface microstructure and microcirculation images of normal and pathologic GI tissues, including Barrett's esophagus, esophageal varices, portal hypertensive gastropathy, gastric antral vascular ectasia, gastric lymphoma, and duodenal adenocarcinoma, were obtained from 72 individual sites in vivo. Differences in vessel diameter, distribution, density, and blood-flow velocity were observed among the GI tissue pathologies imaged.
  
  
  CONCLUSIONS
  To our knowledge, this is the first study to demonstrate the feasibility of EDOCT imaging in the human GI tract during routine endoscopy procedures. EDOCT may detect the different microcirculation patterns exhibited by normal and diseased tissues, which may be useful for diagnostic imaging and treatment monitoring.
authors.affiliation: Faculty of Medicine, Department of Medical Biophysics, University of Toronto, Canada.
authors.forename: Victor X D
authors.initials: VX
authors.lastname: Yang
authors.forename: Shou-Jiang
authors.initials: SJ
authors.lastname: Tang
authors.forename: Maggie L
authors.initials: ML
authors.lastname: Gordon
authors.forename: Bing
authors.initials: B
authors.lastname: Qi
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Gardiner
authors.forename: Maria
authors.initials: M
authors.lastname: Cirocco
authors.forename: Paul
authors.initials: P
authors.lastname: Kortan
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Haber
authors.forename: Gabor
authors.initials: G
authors.lastname: Kandel
authors.forename: I Alex
authors.initials: IA
authors.lastname: Vitkin
authors.forename: Brian C
authors.initials: BC
authors.lastname: Wilson
authors.forename: Norman E
authors.initials: NE
authors.lastname: Marcon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000175:diagnosis; D004379:Duodenal Neoplasms / Q000175:diagnosis; D016145:Endoscopy, Digestive System / Q000379:methods*; D019160:Endosonography / Q000379:methods*; D004932:Esophageal and Gastric Varices / Q000175:diagnosis; D004947:Esophagus / Q000033:anatomy & histology; D005240:Feasibility Studies; D005260:Female; D005753:Gastric Mucosa / Q000033:anatomy & histology; D005767:Gastrointestinal Diseases / Q000175:diagnosis; D041981:Gastrointestinal Tract / Q000033:anatomy & histology; D006801:Humans; D006975:Hypertension, Portal / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D013272:Stomach Diseases / Q000175:diagnosis; D013274:Stomach Neoplasms / Q000175:diagnosis; D013684:Telangiectasis / Q000175:diagnosis; D041623:Tomography, Optical Coherence / Q000379:methods*