THE ROLE OF ULTRASOUND IN THE ASSESSMENT OF OSTEOPOROSIS - A REVIEW

Osteoporosis is now being recognized as a ''silent epidemic'' and ther e is an increasing need to improve its diagnosis and management. Quant itative ultrasound (QUS) measurement [broadband ultrasound attenuation (BUA) and velocity] is emerging as an alternative to photon absorptio metry techniques in the assessment of osteoporosis. The fundamental pr inciples governing ultrasound measurements are discussed, and some of the commercially available clinical systems are reviewed, particularly in relation to data acquisition methods. A review of the published in vivo and in vitro data is presented. The general consensus is that ul trasound seems to provide structural information in addition to densit y. The diagnostic sensitivity of ultrasound measurement of the calcane us in the prediction of hip fracture has been shown by recent large pr ospective studies to be similar to hip bone mineral density (BMD) meas ured with dual-energy X-ray absorptiometry (DXA) and superior to spine BMD. Ultrasound has also been shown to correlate better with the type of hip fracture (intertrochanteric or cervical) than BMD and to provi de comparable diagnostic sensitivity to spine BMD in vertebral fractur es. It has also been observed that combining the results of both ultra sound and DXA BMD significantly improved hip fracture prediction. Area s where further research is required are identified.