Article

Quantitative computed tomography. Eur J Radiol

Department of Radiology, The Royal Infirmary and University, Manchester, UK.
European journal of radiology (Impact Factor: 2.16). 09/2009; 71(3):415-24. DOI: 10.1016/j.ejrad.2009.04.074
Source: PubMed

ABSTRACT Quantitative computed tomography (QCT) was introduced in the mid 1970s. The technique is most commonly applied to 2D slices in the lumbar spine to measure trabecular bone mineral density (BMD; mg/cm(3)). Although not as widely utilized as dual-energy X-ray absortiometry (DXA) QCT has some advantages when studying the skeleton (separate measures of cortical and trabecular BMD; measurement of volumetric, as opposed to 'areal' DXA-BMDa, so not size dependent; geometric and structural parameters obtained which contribute to bone strength). A limitation is that the World Health Organisation (WHO) definition of osteoporosis in terms of bone densitometry (T score -2.5 or below using DXA) is not applicable. QCT can be performed on conventional body CT scanners, or at peripheral sites (radius, tibia) using smaller, less expensive dedicated peripheral CT scanners (pQCT). Although the ionising radiation dose of spinal QCT is higher than for DXA, the dose compares favorably with those of other radiographic procedures (spinal radiographs) performed in patients suspected of having osteoporosis. The radiation dose from peripheral QCT scanners is negligible. Technical developments in CT (spiral multi-detector CT; improved spatial resolution) allow rapid acquisition of 3D volume images which enable QCT to be applied to the clinically important site of the proximal femur, more sophisticated analysis of cortical and trabecular bone, the imaging of trabecular structure and the application of finite element analysis (FEA). Such research studies contribute importantly to the understanding of bone growth and development, the effect of disease and treatment on the skeleton and the biomechanics of bone strength and fracture.

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    • "A sequence of cross-sectional images of tissues are produced in quantitative computed tomography (QCT) based on the amount of X-ray absorbed or attenuated by different tissues through which the X-ray travels [10]. The amount of X-ray absorbed by the tissue at a specific location is expressed as CT number and measured by Hounsfield Unit (HU) in the image. "
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    Applied Bionics and Biomechanics 01/2015; 2015:1-8. DOI:10.1155/2015/837585 · 0.47 Impact Factor
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    • "Thus, in 2000, the National Institute of Health defined in addition to a decreased bone mass new « quality » criteria for the diagnosis of osteoporosis. As these quality criteria are not evaluated by DXA, alternative imaging techniques have been developed to assess bone microarchitecture and improve the fracture risk prediction [9] [10] [11] [12] [13] [14]. "
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    European journal of radiology 06/2013; 82(9). DOI:10.1016/j.ejrad.2013.04.042 · 2.16 Impact Factor
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