title: Toward clinical X-ray phase-contrast CT: demonstration of enhanced soft-tissue contrast in human specimen.
abstract: OBJECTIVE
  X-ray computed tomography (CT) using phase contrast can provide images with greatly enhanced soft-tissue contrast in comparison to conventional attenuation-based CT. We report on the first scan of a human specimen recorded with a phase-contrast CT system based on an x-ray grating interferometer and a conventional x-ray tube source. Feasibility and potential applications of preclinical and clinical phase-contrast CT are discussed.
  
  
  METHODS
  A hand of an infant was scanned ex vivo at 40 kVp tube voltage. The simultaneously recorded attenuation and phase-contrast CT images were quantitatively compared with each other, by introducing a specific Hounsfield unit for phase-contrast imaging.
  
  
  RESULTS
  We observe significantly enhanced soft-tissue contrast in the phase images, when compared with the attenuation data. Particularly, tendons and ligaments appear with strongly increased contrast-to-noise ratio.
  
  
  CONCLUSIONS
  Our results demonstrate the huge potential of phase-contrast CT for clinical investigations of human specimens and, potentially, of humans. Because the applied technique works efficiently with conventional x-ray tubes and detectors, it is suitable for the realization of preclinical and clinical phase-contrast CT systems.
authors.affiliation: Paul Scherrer Institut, Villigen PSI, Switzerland. tilman.donath@dectris.com
authors.forename: Tilman
authors.initials: T
authors.lastname: Donath
authors.forename: Franz
authors.initials: F
authors.lastname: Pfeiffer
authors.forename: Oliver
authors.initials: O
authors.lastname: Bunk
authors.forename: Christian
authors.initials: C
authors.lastname: Grünzweig
authors.forename: Eckhard
authors.initials: E
authors.lastname: Hempel
authors.forename: Stefan
authors.initials: S
authors.lastname: Popescu
authors.forename: Peter
authors.initials: P
authors.lastname: Vock
authors.forename: Christian
authors.initials: C
authors.lastname: David
mesh_terms: D002102:Cadaver; D003238:Connective Tissue / Q000000981:diagnostic imaging*; D006225:Hand / Q000000981:diagnostic imaging*; D006801:Humans; D007231:Infant, Newborn; D010865:Pilot Projects; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014961:X-Ray Diffraction / Q000379:methods*