Dual-energy X-ray Absorptiometry (DEXA) imaging is an x-ray-based technique to determine bone mineral density (BMD) and body composition (body fat mass). Two x-ray beams with differing energy levels are used to image the entire animal in a planar fashion. When soft tissue absorption is subtracted, the BMD can be determined from the absorption of each beam by bone.
DEXA is the most widely used and, most thoroughly studied, bone density measurement technology and can be applied to osteoporosis models such as the ovariectomy model, rheumatoid arthritis models, and bone metastasis models. In addition, this modality has strong utility in the non-invasive measurement of body composition in obesity models such as diet-induced obesity or OB/OB mice.