The effect of frequency-dependent attenuation on predicted histotripsy waveforms in tissue mimicking phantoms

摘要

Tissue-mimicking phantoms are employed for the assessment of shocked histotripsy pulses in vitro. These broadband shockwaves are critical for tissue ablation, and are influenced by the frequency-dependent attenuation of the medium. The density, sound speed, and attenuation spectra (2–25 MHz) were measured for phantoms that mimic key histotripsy targets. The influence of nonlinear propagation relative to the attenuation was described in terms of the Gol’dberg number. An expression was derived to estimate the bandwidth of shocked histotripsy pulses for power law-dependent attenuation. The expression is independent of the fundamental frequency of the histotripsy pulse for linear frequency-dependent attenuation.