Dual-energy digital radiography for the assessment of bone mineral density.
BACKGROUND
Bone mineral density (BMD) is usually determined by dual-energy X-ray absorptiometry (DXA). Digital radiography (DR) has enabled the application of dual-energy techniques for separating bone and soft tissue, but it is not clear yet whether BMD information can reliably be obtained using DR.


OBJECTIVE
To determine the ability of dual-energy digital radiography (DEDR) to predict BMD as determined by DXA.


METHODS
Reindeer femora (n=15) were imaged in a water bath at a typical clinical imaging voltage of 79 kVp and additionally at 100 kVp on a DR system. BMD was determined in four segmented regions (femoral neck, trochanter, inter-trochanter, Ward's triangle) from these images using the DXA calculation principle. BMD results as determined by DEDR were compared with BMD values as determined by DXA.


RESULTS
Significant moderate to high linear correlations (0.66-0.76) were observed at the femoral neck, Ward's triangle, and trochanter between BMD values as determined by the two techniques. The coefficient of variation (CV(RMS)) ranged between 2.2 and 4.7% and 0.2 and 1.8% for DEDR and DXA analyses, respectively.


CONCLUSIONS
DXA-based BMD information can be obtained with moderate precision and accuracy using DEDR. In future, combining BMD measurements using DEDR with structural and geometrical information available on digital radiographs could enable a more comprehensive assessment of bone.
Tahvanainen
Päivi S
PS
Department of Diagnostic Radiology, Oulu University Hospital, Oulu, Finland. paivi.tahvanainen@oulu.fi
Lammentausta
Eveliina
E
Pulkkinen
Pasi
P
Tervonen
Osmo
O
Jämsä
Timo
T
Nieminen
Miika T
MT
D015502:Absorptiometry, Photon; D000818:Animals; D015519:Bone Density; D005269:Femur / Q000000981:diagnostic imaging*; D066298:In Vitro Techniques; D011856:Radiographic Image Enhancement; D012053:Reindeer; D015203:Reproducibility of Results