Figure 2.

Schematic of bubble size (right hand ordinate) as a function of time when subject to a single cycle of a shocked histotripsy pulse (left hand ordinate). ‘R_r’ corresponds to the radius of the bubble at time τ_r, when the excitation pressure transitions from tensile to compressional (i.e. the shockwave front). The effective pressure for the analytic model, equation (3), is set to the magnitude of the rarefactional pressure, |p_r|, for shock scattering histotripsy. The frequency dependence inherent in the analytic model is dependent on the duration of the rarefactional phase of the acoustic pressure, τ_r, via equation (7).