title: Diffraction-enhanced X-ray imaging of articular cartilage.
abstract: OBJECTIVE
  To introduce a novel X-ray technology, diffraction-enhanced X-ray imaging (DEI), in its early stages of development, for the imaging of articular cartilage.
  
  
  METHODS
  Disarticulated and/or intact human knee and talocrural joints displaying both undegenerated and degenerated articular cartilage were imaged with DEI. A series of three silicon crystals were used to produce a highly collimated monochromatic X-ray beam to achieve scatter-rejection at the microradian level. The third crystal (analyser) was set at different angles resulting in images displaying different characteristics. Once the diffraction enhanced (DE) images were obtained, they were compared to gross and histological examination.
  
  
  RESULTS
  Articular cartilage in both disarticulated and intact joints could be visualized through DEI. For each specimen, DE images were reflective of their gross and histological appearance. For each different angle of the analyser crystal, there was a slight difference in appearance in the specimen image, with certain characteristics changing in their contrast intensity as the analyser angle changed.
  
  
  CONCLUSIONS
  DEI is capable of imaging articular cartilage in disarticulated, as well as in intact joints. Gross cartilage defects, even at early stages of development, can be visualized due to a combination of high spatial resolution and detection of X-ray refraction, extinction and absorption patterns. Furthermore, DE images displaying contrast heterogeneities indicative of cartilage degeneration correspond to the degeneration detected by gross and histological examination.
authors.affiliation: Department of Biochemistry, Rush Medical College, 1653 W. Congress Parkway, Chicago, Illinois 60612, USA.
authors.forename: J
authors.initials: J
authors.lastname: Mollenhauer
authors.forename: M E
authors.initials: ME
authors.lastname: Aurich
authors.forename: Z
authors.initials: Z
authors.lastname: Zhong
authors.forename: C
authors.initials: C
authors.lastname: Muehleman
authors.forename: A A
authors.initials: AA
authors.lastname: Cole
authors.forename: M
authors.initials: M
authors.lastname: Hasnah
authors.forename: O
authors.initials: O
authors.lastname: Oltulu
authors.forename: K E
authors.initials: KE
authors.lastname: Kuettner
authors.forename: A
authors.initials: A
authors.lastname: Margulis
authors.forename: L D
authors.initials: LD
authors.lastname: Chapman
mesh_terms: D000328:Adult; D000368:Aged; D000843:Ankle Joint / Q000000981:diagnostic imaging*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging*; D011859:Radiography; D013679:Technology, Radiologic / Q000379:methods*; D014961:X-Ray Diffraction / Q000379:methods