What is Dexa Scanning?
Dual Energy X-ray Absortiometry, or DEXA scanning, is currently the most widely used method to measure bone mineral density. For the test, a patient lies down on an examining table, and the scanner rapidly directs x-ray energy from two different sources towards the bone being examined in an alternating fashion at a set frequency. The mineral density of the patient’s bone weakens, or prolongs the transmission of these two sources of x-ray energy through a filter onto a counter in a degree related to the amount of bone mass present. The greater the bone mineral density, the greater the signal picked up by the photon counter. The use of the two different x-ray energy sources rather than more traditional radioisotope studies (such that would be used for a bone scan) greatly improves the precision and accuracy of the measurements. DEXA scanning has become the most widely used method for measuring bone mineral density for several reasons. When compared with radiographic absortiometry or sing
