On the use of coded excitation and pulse compression to reduce estimate error of average scatterer diameters obtained from ultrasonic backscatter.

Abstract

A technique that extends the tradeoff of variance of average scatterer diameter (ASD) estimates and the spatial resolution in quantitative ultrasound (QUS) images is proposed. Resolution enhancement compression (REC), a coded excitation and pulse compression technique, was used to enhance the −6‐dB bandwidth of an ultrasonic imaging system. The objective of this study was to combine REC with QUS (REC‐QUS), and evaluate and compare improvements in ASD estimates obtained using the REC technique to conventional pulsing (CP) methods. Simulations and experimental measurements were conducted with a 10 MHz weakly focused (f/4) single‐element transducer (−6‐dB bandwidth of 80%). Using REC, the −6‐dB bandwidth was enhanced to 152%. In simulations, a homogeneous phantom with scatterers 50 μm in diam was evaluated. In experimental measurements, a tissue‐mimicking phantom that contained glass spheres with scatterer diam that range from 45 to 53 μm was evaluated. Estimates of ASD were obtained by comparing the normali...