4C-1 Empirical Validation of the Theoretical Frameworks Underlying Ultrasound Scattering in Tissue

Scatterer properties have been related to ultrasonic spectral parameters using theoretical frameworks first established by Lizzi et al. This study aims to validate these frameworks directly by means of experiments designed to reduce the reliance on specific assumptions. Two transducers with center frequencies of 24 MHz and 21.5 MHz and f-numbers of 2 and 5 respectively, were used to scan different concentrations of dextran gel beads in suspension. Backscattered radio-frequency (RF) data were processed using standard Fourier methods, and the spectral parameters computed from these data were compared with parameter values predicted by the Lizzi framework. The slope parameter values computed from data acquired with the two transducers were similar, suggesting that the slope may be less sensitive to transducer properties than suggested by the theory. The midband and intercept parameter values increased with increasing concentration of gel beads in both cases, as expected.