Faculty Collaboration Database

Accuracy and precision of PIXImus densitometry for ex vivo mouse long bones: comparison of technique and software version. J Clin Densitom 2004;7(3):326-33

Date

08/21/2004

Pubmed ID

15319505

DOI

10.1385/jcd:7:3:326

Scopus ID

2-s2.0-4444305471 (requires institutional sign-in at Scopus site)   20 Citations

Abstract

Many densitometric studies in mice assess bone mineral density (BMD) at specified regions of interest, often using ex vivo specimens. In the present study, we sought to determine the precision and accuracy of ex vivo densitometry of mouse bones, comparing two software versions and two data acquisition techniques. The newer software allows manual adjustment of the threshold value for bone, improving the ability to analyze bone edges correctly. Root mean square standard deviations were 2-3 mg/cm2, with coefficients of variation ranging between 3% and 5% for femora and humeri and between 6% and 7% for radii. The regression coefficients for bone mineral content as a function of ash mass were near 1 for femora and humeri, but considerably lower for radii. Coefficients of determination were inversely related to bone size, with R2 values exceeding 0.9 at the femur, 0.8 at the humerus, and ranging between 0.3 and 0.6 at the radius. We found that our instrument has a position artifact, with BMD and bone mineral content dependent on the specimen's coordinates in the scanned field. Our findings establish the limitations of ex vivo densitometry with the PIXImus and support our recommendation that investigators seek position artifacts in their instruments.

Author List

Lopez Franco GE, O'Neil TK, Litscher SJ, Urban-Piette M, Blank RD

MESH terms used to index this publication - Major topics in bold

Absorptiometry, Photon
Animals
Artifacts
Bone Density
In Vitro Techniques
Mice
Mice, Inbred C57BL
Reproducibility of Results
Software