Feasibility of tissue effects produced by noninvasive high frequency intense therapy ultrasound via inertial cavitation

Considerable attention has been paid to ultrasound assisted delivery at relatively low frequency (20 kHz-3 MHz) and low acoustic intensity (<;3W/cm
²
). The purported mechanism of action is associated with cavitation increasing drug diffusion through the stratum corneum and epidermis. We show a feasibility of delivering clinically useful medicants through stratum corneum into skin utilizing Intense Therapeutic Ultrasound (ITU) high frequency (2.9-10 MHz), high intensity (>1,000 W/cm
²
) sound. Boiling histotripsy effects are also possible with ITU. Purported mechanism of action would include inertial cavitation and high pressure (>1MPa).