New ultrasound system for bone assessment

This paper reports on a new ultrasound device for noninvasive assessment of bone. The device, known as the QRT 2000 - for Quantitative Real-Time -- is entirely self-contained, portable, and handheld. The QRT 2000 is powered by 4 "AA" rechargeable batteries and permits near real-time evaluation of a novel set of ultrasound parameters and their on-line display to the user. The parameters have been studied both in vitro and clinically with a laboratory unit that measured the calcaneus in through transmission and computed the ultrasound features off-line. The data related the ultrasound parameters to the bone mineral density (BMD) of the calcaneus, spine and hip, as determined by x-ray absorptiometry, and demonstrated that the parameters were superior to the standard ones known as BUA and SOS (broadband ultrasound attenuation and speed-of-sound, respectively). The QRT 2000 was then constructed to compute the same parameters; however as noted above it does this in near real-time and provides visual feedback to the user while the measurements are being made. The compactness and portability of the unit make it also ideal for spaceflight applications. Finally, the QRT 2000 was designed to be manufactured at relatively low cost, and therefore should enable the significant expansion of quantitative ultrasound measurements to, for example, primary care physicians in this country and abroad, and including for use in the developing world.