title: Multi-detector row CT imaging of vertebral microstructure for evaluation of fracture risk.
abstract: We applied MDCT for in vivo evaluation of the microarchitecture of human vertebrae. Microstructure parameters, such as structure model index, Euler's number, and bone volume fraction, revealed higher relative risk for prevalent vertebral fracture than did BMD obtained by DXA. Thus, microstructure analysis by MDCT, together with simultaneously obtained volumetric BMD values, is useful for clinical assessment of fracture risk.
  
  
  BACKGROUND
  BMD measurement by DXA alone has limitations in predicting fracture, and methods for clinical assessment of bone quality, such as microstructure, are awaited. This study was undertaken to examine the applicability of multidetector row CT (MDCT) for in vivo evaluation of trabecular microstructure.
  
  
  METHODS
  Optimal conditions for MDCT scanning were determined at a spatial resolution of 250 x 250 x 500 mum, using muCT data of excised human vertebra specimens as a reference. We analyzed the trabecular microstructure of the vertebrae of 82 postmenopausal women (55-76 years old), including 39 women with and 43 without a recent vertebral fracture.
  
  
  RESULTS
  Microstructure indices obtained by MDCT scanning revealed higher relative risk for prevalent vertebral fracture (OR: 16.0 for structure model index, 13.6 for bone volume fraction, and 13.1 for Euler's number) than did spinal BMD obtained by DXA (OR: 4.8). MDCT could also provide volumetric BMD data, which had higher diagnostic value (OR: 12.7) than did DXA.
  
  
  CONCLUSIONS
  Vertebral microarchitecture can be visualized by MDCT, and microstructure parameters obtained by MDCT, together with volumetric BMD, provided better diagnostic performance for assessing fracture risk than DXA measurement.
authors.affiliation: Department of Radiology, Nagasaki University School of Medicine, Nagasaki, Japan. masako@net.nagasaki-u.ac.jp
authors.forename: Masako
authors.initials: M
authors.lastname: Ito
authors.forename: Kyoji
authors.initials: K
authors.lastname: Ikeda
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nishiguchi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shindo
authors.forename: Masataka
authors.initials: M
authors.lastname: Uetani
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hosoi
authors.forename: Hajime
authors.initials: H
authors.lastname: Orimo
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries*; D008875:Middle Aged; D017698:Postmenopause; D012307:Risk Factors; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000453:epidemiology; D014057:Tomography, X-Ray Computed / Q000379:methods