Search results
Results from the WOW.Com Content Network
A scanner used to measure bone density using dual energy X-ray absorptiometry. Bone density, or bone mineral density, is the amount of bone mineral in bone tissue.The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to optical density per square centimetre of bone surface upon imaging. [1]
Bone densities are often given to patients as a T score or a Z score. A T score tells the patient what their bone mineral density is in comparison to a young adult of the same gender with peak bone mineral density. A normal T score is -1.0 and above, low bone density is between -1.0 and -2.5, and osteoporosis is -2.5 and lower.
The BMD is corrected for porosity of the bone, estimated by a texture analysis performed on the cortical part of the bone. [2] [3] Like other technologies for estimating the bone mineral density, the outputs are an areal BMD value, a T-score and a Z-score for assessing osteoporosis and the risk of bone fracture. [4]
Medicare may cover bone density tests if a doctor deems them medically necessary. This may be because a person has osteoporosis, estrogen deficiency, or primary hyperparathyroidism, for example.
DXA is only able to provide the areal bone mineral density. High-resolution peripheral quantitative computed tomography (HR-pQCT) is better than DXA at detecting bone microarchitecture, modeling whole-bone geometry using 3-dimensional information from scans. This method allows estimation of bone strength and other mechanical properties. [20]
The standard in bone mineral density scanning developed in the 1980s is called Dual X-ray Absorptiometry, known as DXA. The DXA technique uses two different x-ray energy levels to estimate bone density. DXA scans assume a constant relationship between the amounts of lean soft tissue and adipose tissue.
Bone density. The basic principle of single-photon bone mineral density measuring instrument is to calculate the attenuation degree of single-energy gamma photon beam through bone tissue. The more attenuation degree is, the more absorbed by bone minerals, the more bone mineral content and the higher bone mineral density are.
The analysis is performed in the frequency domain. Bone mineral density is estimated by comparing the results against reference models. The accuracy has been tested by comparing it against to DXA technology. [1] [2] [3] [4]