dual emission X-ray absorptiometry (DEXA)

(redirected from dual emission X-ray absorptiometry DEXA)

dual emission X-ray absorptiometry (DEXA)

a scanning technique that is currently the most widely used method of measuring bone mineral density. The subject lies on a table and the scanner directs X-ray energy from two sources (increasing the accuracy) at the bone being examined. The greater the bone mineral density, the greater the signal picked up by the photon counter. DEXA scanning is more accurate than other methods (e.g. plain X-ray): quick, non-invasive, exposes the subject to less radiation and is relatively inexpensive. Estimation of bone mineral density is a good predictor of fracture risk and DEXA can be used to screen those most at risk (postmenopausal women, previous fracture victims, smokers and those on long-term corticosteroids). DEXA can also be used for a three-compartment assessment of body composition, estimating lean body mass, fat mass and bone mass. See also osteoporosis.
Full browser ?