Single X-ray absorptiometry of the forearm: precision, correlation, and reference data.

T L Kelly; G Crane; D T Baran

doi:10.1007/bf00301681

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Single X-ray absorptiometry of the forearm: precision, correlation, and reference data.

T L Kelly·G Crane·D T Baran

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Abstract

The performance of a single X-ray absorptiometry (SXA) device incorporating an X-ray tube as a photon source was evaluated with respect to precision in vivo and in vitro, scan time, image quality, and correlation with an existing dual energy X-ray absorptiometry (DXA) device. SXA precision in vivo, expressed as a coefficient of variation (CV), was 0.66% for bone mineral content (BMC) and 1.05% for bone mineral density (BMD). Precision in vitro, based on 78 BMC measurements of a forearm phantom over 195 days, was 0.53%. Correlation with DXA at the 8 mm distal forearm site was high (r = 0.97 for BMC and r = 0.96 for BMD). A preliminary SXA reference database composed of 151 healthy Caucasian American women was developed to facilitate the interpretation of patient measurements. SXA scan time was 4 minutes and delivered a radiation exposure of 1.68 mrem. SXA image quality and spatial resolution were superior to SPA and comparable to DXA.

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Absorptiometry, Photon Adult Aged Aged, 80 and over Bone Density Computer Simulation Female Forearm Humans Middle Aged Osteoporosis Reference Values Reproducibility of Results Journal Article

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T L Kelly, G Crane, D T Baran. 1994. Single X-ray absorptiometry of the forearm: precision, correlation, and reference data.. https://doi.org/10.1007/bf00301681

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