Dual-energy X-ray absorptiometry (DXA, previously DEXA) is the gold standard technique used for the management and follow-up of osteoporosis.
DXA is a means of measuring bone mineral density (BMD). Two X-ray beams, with different energy levels, are aimed at the patient’s bones. When soft tissue absorption is subtracted out, the bone mineral density (BMD) can be determined from the absorption of each beam by bone. Dual-energy X-ray absorptiometry is the most widely used and most thoroughly studied bone density measurement technology.

3DDXA algorithms-based technology relies on a population database of QCT scans, to create a shape and density 3D model, that is then registered onto a patient hip DXA scan. In a second step, the cortex is segmented in order to separate cortical from trabecular bone. This provides a patient-specific 3D model of the hip and facilitates specific cortical and trabecular bone measurements.

Source: https://3ddxa.net/