Which two modes are utilized for measurement in Dual X-ray Absorptiometry (DXA)?

• A. Rotation Speed and Thickness Levels
• B. Scan Speed and Thickness Levels
• C. Speed of Light and Frequency Levels
• D. Time of Scan and Density Levels

Answer: (B)

In Dual X-ray Absorptiometry (DXA), the measurement of bone density relies on two key modes: scan speed and thickness levels.

Scan speed refers to how quickly the DXA device moves across the area of interest during the imaging process. A faster scan speed can increase the throughput of scans, which may be beneficial in a clinical setting where efficiency is essential. However, it must be balanced with the need for accurate measurement, as too fast a scan speed could potentially miss critical density information.

Thickness levels are important because they refer to the varying thickness of the body part being examined. Different sections of bone may vary in density based on thickness, as thicker areas of bone generally provide more attenuation of X-rays. This effective measurement helps in accurately assessing the bone mineral density (BMD) across regions of interest, enabling the identification of conditions such as osteoporosis.

Overall, utilizing both scan speed and thickness levels allows for optimized accuracy and efficiency in DXA measurements, essential for evaluating bone health and making informed clinical decisions.