2A-6 Optimization Algorithm for Improved Quantitative Ultrasound Signal Processing at the Proximal Femur

To improve the prediction of the osteoporotic fracture risk at the proximal femur we are developing a scanner for quantitative ultrasound (QUS) measurements at this site. Due to multipath transmission in this complex shaped bone conventional signal processing techniques developed for QUS measurements at peripheral sites frequently fail. Applying a model-based estimation method to quantitative ultrasound scans of excised proximal femurs the fraction of evaluable signals can be increased from approx. 60% (using conventional algorithms) to 95%. The correlation of the standard QUS variables broadband ultrasound attenuation (BUA) and speed-of-sound (SOS) with the established variable bone mineral density (BMD) reported in previous studies is maintained (r ² BUA/BMD = 0.69, r² SOS/BMD = 0.82). Because of its ability to separate superimposed signals this approach opens up further diagnostic potential by evaluating the information of waves of different sound paths through the bone