Multi-detector row CT imaging of vertebral microstructure for evaluation of fracture risk.
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.
Ito
Masako
M
Department of Radiology, Nagasaki University School of Medicine, Nagasaki, Japan. masako@net.nagasaki-u.ac.jp
Ikeda
Kyoji
K
Nishiguchi
Masahiko
M
Shindo
Hiroyuki
H
Uetani
Masataka
M
Hosoi
Takayuki
T
Orimo
Hajime
H
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