title: Contrast effect of blood on phase-contrast X-ray imaging.
abstract: OBJECTIVE
  As a preliminary study for application of phase-contrast X-ray imaging to medicine, we measured the X-ray refractive index of human blood and its influence on image contrast.
  
  
  METHODS
  Using an X-ray interferometer, the X-ray phase shifts caused by human blood and its ingredients were measured from the interval of interference fringes.
  
  
  RESULTS
  The X-ray phase shift caused by blood was 3% larger than that caused by serum.
  
  
  CONCLUSIONS
  The large phase shift caused by blood is due to red blood cells, which contain hemoglobin molecules with iron atoms. It is possible that blood produces a structure in a phase-contrast X-ray image.
authors.affiliation: Advanced Research Laboratory, Hitachi, Ltd., Hatoyama, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Momose
authors.forename: T
authors.initials: T
authors.lastname: Takeda
authors.forename: Y
authors.initials: Y
authors.lastname: Itai
mesh_terms: D001769:Blood / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007368:Interferometry; D008962:Models, Theoretical; D011859:Radiography