Quantitation of bone mineral by dual photon absorptiometry (DPA): Evaluation of instrument performance

Conference · Sun Jan 01 04:00:00 EST 1984 · J. Nucl. Med.; (United States)

OSTI ID:6860579

Dunn, W L; O'Duffy, A; Wahner, H W

Quantitation of bone mineral is used with increasing frequency for clinical studies. This paper details the principle of DPA and present an evaluation of the technique. DPA measurements were performed with a scanning dual photon system constructed at this institution and modeled after the device developed at the University of Wisconsin. The components are a rectilinear scanner frame, 1.5 Ci Gd-153 source, NaI(TL) detector and a PDP 11/03 computer. Dual discriminator windows are set on the 44 and 100 keV photon energies of Gd-153. Instrument linearity, accuracy and reproducibility were evaluated with ashed bone standards and simulated tissue covering. In these experiments computed and actual bone mineral have a correlation coefficient of 1.0 and a SEE of approximately 1.0% (Linear regression analysis). Precision and accuracy of a standard were studied over a period of two years. Mean error between actual and measured bone mineral was 0.28%. In vivo precision in six subjects averaged 2.3% (CV) for lumbar spine measurements. The effect of soft tissue compositional change was studied with ashed bone standards and human cadaver spine specimens. Intraosseous fat changes of 50% produced an average bone mineral measurement error of 1.4%. A 20% change in fat thickness produced a 2.5% error. In situ and in vitro scans of 9 cadaver spines were performed to study the effect of extraosseous fat. The mean percent difference between the two measurements was 0.7% (SEE=3.2%).

• Research Organization: Mayo Clinic, Mayo Foundation, Rochester, MN
• OSTI ID: 6860579
• Report Number(s): CONF-840619-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 25:5
• Country of Publication: United States
• Language: English

Related Subjects

550602* -- Medicine-- External Radiation in Diagnostics-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMAL TISSUES
BIOMEDICAL RADIOGRAPHY
BODY
BONE TISSUES
CHEMICAL ANALYSIS
CONNECTIVE TISSUE
DIAGNOSTIC TECHNIQUES
EVALUATION
IN VIVO
MEDICINE
MINERALS
NUCLEAR MEDICINE
OSTEODENSITOMETRY
PERFORMANCE
QUANTITATIVE CHEMICAL ANALYSIS
RADIOLOGY
TISSUES