Which texture index evaluates the pixel gray-level variations in lumbar spine DXA images?

• A. BMD (Bone Mineral Density)
• B. TBS (Trabecular Bone Score)
• C. QCT (Quantitative Computed Tomography)
• D. DXA (Dual-energy X-ray Absorptiometry)

Answer: (B)

The Trabecular Bone Score (TBS) is specifically designed to evaluate the texture of bone, particularly in lumbar spine DXA images. It assesses the pixel gray-level variations in these images, which reflect the microarchitecture of the trabecular bone. A higher TBS suggests better bone quality and a lower risk of fracture, which is important in the assessment of osteoporosis and other bone-related conditions.

TBS works by analyzing the variability in pixel intensities, as variations indicate changes in the bone structure at a finer level than what Bone Mineral Density (BMD) alone provides. This additional layer of analysis helps clinicians make more informed decisions regarding patient management and treatment plans for bone health.