What is considered the "gold standard" for measuring bone mass?

• A. CT scan
• B. X-ray
• C. DEXA
• D. MRI

Answer: (C)

The "gold standard" for measuring bone mass is DEXA, which stands for Dual-Energy X-ray Absorptiometry. DEXA is widely recognized for its capability to provide precise and accurate measurements of bone mineral density (BMD) at various skeletal sites, particularly the lumbar spine and hip. The technology utilizes two different X-ray energy beams to assess bone density, allowing it to differentiate between bone and soft tissue effectively.

This method not only has high sensitivity and specificity for detecting osteoporosis and other bone-related conditions, but it also offers the advantage of lower radiation exposure compared to other imaging techniques. These factors make DEXA particularly valuable in clinical practice for diagnosing and managing conditions such as osteopenia and osteoporosis.

In contrast, while other imaging modalities like CT scans, X-rays, and MRIs can provide information about bone structure and health, they are not primarily designed for the specific task of measuring bone density like DEXA is. Thus, their use in assessing bone mass and health is less precise and not considered the standard in this context.