What is the primary purpose of dual-energy X-ray absorptiometry (DXA) in bone densitometry?

• A. To diagnose fractures
• B. To measure bone mineral density
• C. To evaluate joint health
• D. To assess soft tissue conditions

Answer: (B)

The primary purpose of dual-energy X-ray absorptiometry (DXA) in bone densitometry is to measure bone mineral density (BMD). This technique utilizes two different X-ray energy levels to differentiate between bone and soft tissue, allowing for an accurate evaluation of the amount of mineral content in bones. BMD measurements obtained through DXA are critical for diagnosing conditions such as osteoporosis and assessing an individual's fracture risk.

By quantifying the density of bone, healthcare providers can make informed decisions regarding patient care and management, including the need for lifestyle changes, supplementation, or medications aimed at improving bone health. The significance of BMD as a parameter lies in its correlation with bone strength and susceptibility to fractures, making it an essential tool in the arena of bone health assessment.