radiodensitometri

Radiodensitometry is a set of techniques that quantify the density of biological tissues using X-ray attenuation to infer mineral content or density. The method relies on the correlation between X-ray attenuation and material density, typically expressed as bone mineral density (BMD) or tissue density. It is commonly used to assess bone health but can be applied to other tissues.

The most widely used modality is dual-energy X-ray absorptiometry (DEXA), which measures areal BMD (g/cm^2) at sites such as the hip and spine and provides T-scores and Z-scores for osteoporosis assessment. Quantitative computed tomography (QCT) yields volumetric BMD (mg/cm^3) and can separate cortical from trabecular bone, with higher costs and radiation.

Other radiodensitometry methods include single-energy absorptiometry and radiographic absorptiometry; dental radiodensitometry uses dental radiographs to estimate tooth mineral density. All methods require calibration against reference phantoms and standardized protocols to enable comparisons across devices and populations.

Clinical use centers on osteoporosis risk assessment, monitoring therapy, and research into mineralization disorders. Limitations include sensitivity to degenerative changes, artifacts, and age- or site-specific reference ranges. Radiation exposure is low but nonzero, and results depend on equipment and calibration.