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The X-ray attenuation characteristics and density of human calcaneal marrow do not change significantly during adulthoodChanges in the material characteristics of bone marrow with aging can be a significant source of error in measurements of bone density when using X-ray and ultrasound imaging modalities. In the context of computed tomography, dual-energy computed techniques have been used to correct for changes in marrow composition. However, dual-energy quantitative computed tomography (DE-QCT) protocols, while increasing the accuracy of the measurement, reduce the precision and increase the radiation dose to the patient in comparison to single-energy quantitative computed tomography (SE-QCT) protocols. If the attenuation properties of the marrow for a particular bone can be shown to be relatively constant with age, it should be possible to use single-energy techniques without experiencing errors caused by unknown marrow composition. Marrow was extracted by centrifugation from 10 mm thick frontal sections of 34 adult cadaver calcanei (28 males, 6 females, ages 17-65 years). The density and energy-dependent linear X-ray attenuation coefficient of each marrow sample were determined. For purposes of comparing our results, we then computed an effective CT number at two GE CT/i scan voltages (80 and 120 kVp) for each specimen. The coefficients of variation for the density, CT number at 80 kVp and CT number at 120 kVp were each less than 1%, and the parameters did not change significantly with age (p > 0.2, r2 < 0.02, power > 0.8 where the minimum acceptable r2 = 0.216). We could demonstrate no significant gender-associated differences in these relationships. These data suggest that calcaneal bone marrow X-ray attenuation properties and marrow density are essentially constant from the third through sixth decades of life.
Document ID
20040088285
Acquisition Source
Ames Research Center
Document Type
Reprint (Version printed in journal)
Authors
Les, C. M.
(NASA Ames Research Center Moffett Field CA United States)
Whalen, R. T.
Beaupre, G. S.
Yan, C. H.
Cleek, T. M.
Wills, J. S.
Date Acquired
August 21, 2013
Publication Date
May 1, 2002
Publication Information
Publication: Journal of orthopaedic research : official publication of the Orthopaedic Research Society
Volume: 20
Issue: 3
ISSN: 0736-0266
Subject Category
Aerospace Medicine
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Musculoskeletal
NASA Center ARC

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