Time Domain Measure of Transient Shear Wave Attenuation.

Transient shear waves from push pulses can be used in elastography to estimate shear wave speed and attenuation, as a step towards the viscoelastic characterization of tissue. While many implementations are in use, less attention has been paid to practical issues of the strong influence of the inevitable background motions of tissue and transducer, the limited time and sampling available, and the deleterious effects of these on spectral estimates. To mitigate these issues, we propose several physics-based steps, first to correct for baseline drift and second to eliminate the need for Fourier transforms by completing all estimations on time domain energy. We target the estimation of shear wave attenuation, and preliminary results are shown for two phantoms and two in vivo livers to demonstrate the potential of this approach, which can serve as an alternative pathway towards shear wave attenuation of tissues for clinical assessment of tissue elastography.