Bone characterization with ultrasound: state of the art and new proposal.

Ultrasound transmission measurement through the os calcis is an emerging technique and a promising clinical tool for early assessment of osteoporosis. In this paper we first present a short discussion on the physical meaning of ultrasound velocity and attenuation, the methods of measurements and the potential contribution of ultrasound compared to photon absorptiometry. After analysing the various results in vivo published up to now we shall present some new perspectives of ultrasonic bone characterization: broadband ultrasonic attenuation imaging (BUAI) and pulse-echo measurement.