Which imaging modality measures bone density to diagnose osteoporosis?

Which imaging modality measures bone density to diagnose osteoporosis?

• A. Computed Tomography
• B. Nuclear Medicine
• C. Bone Densitometry
• D. Radiography

Answer: (C)

Measuring bone density to diagnose osteoporosis is done with bone densitometry, most commonly through a dual-energy X-ray absorptiometry (DEXA) scan. DEXA provides a quantitative bone mineral density at sites such as the lumbar spine and hip and yields a T-score; a T-score of -2.5 or lower indicates osteoporosis. This directly assesses density, which is what osteoporosis is defined by. Radiographs show fractures and structural changes but don’t reliably quantify density; nuclear medicine evaluates bone metabolism rather than density; CT can estimate density but isn’t the standard diagnostic tool for osteoporosis due to higher radiation and cost.

Measuring bone density to diagnose osteoporosis is done with bone densitometry, most commonly through a dual-energy X-ray absorptiometry (DEXA) scan. DEXA provides a quantitative bone mineral density at sites such as the lumbar spine and hip and yields a T-score; a T-score of -2.5 or lower indicates osteoporosis. This directly assesses density, which is what osteoporosis is defined by. Radiographs show fractures and structural changes but don’t reliably quantify density; nuclear medicine evaluates bone metabolism rather than density; CT can estimate density but isn’t the standard diagnostic tool for osteoporosis due to higher radiation and cost.