Body composition analysis by DEXA by using dynamically changing samarium filtration.

A Gotfredsen; L Baeksgaard; J Hilsted

doi:10.1152/jappl.1997.82.4.1200

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Body composition analysis by DEXA by using dynamically changing samarium filtration.

A Gotfredsen·L Baeksgaard·J Hilsted

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Abstract

Dual-energy X-ray absorptiometry (DEXA) has a high accuracy for body composition analysis but is influenced by beam hardening and other error sources in the extremes of measurement. To compensate for beam hardening, the Norland XR-36 introduces a dynamically changing samarium filtration system, which depends on the current-absorber thickness. With this system we found a good agreement (r = 0.99) between reference and measured amounts of tissue or fat percentages in a plastic phantom and in smaller (approximately 0.5-4 kg) and larger (approximately 5-20 kg) piles of tissue (ox muscle and lard). Scans of six healthy volunteers covered with combinations of beef and lard (approximately 5-15 kg) showed a good agreement (r = 0.99) between reference and DEXA values of added soft tissue mass and fat percentage. We conclude that the DEXA method (and, in particular, the Norland XR-36 using dynamic filtration) has a high accuracy for body composition analysis. It has a potential for gaining status as a reference method in the future and may presently be used as a supplement to the traditional methods for body composition analysis.

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Absorptiometry, Photon Adult Animals Body Composition Bone Density Cattle Evaluation Studies as Topic Humans Image Processing, Computer-Assisted Lipids Male Models, Anatomic Muscle, Skeletal Regression Analysis Samarium Clinical Trial Journal Article Research Support, Non-U.S. Gov't

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A Gotfredsen, L Baeksgaard, J Hilsted. 1997. Body composition analysis by DEXA by using dynamically changing samarium filtration.. https://doi.org/10.1152/jappl.1997.82.4.1200

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