These are featured by (A) stable cavitation, (B) translation, and (C) inertial cavitation. The PI images show delivery from the extracellular space, while the post-US calcein images show cellular viability. (D) When characterized by change in bubble radius per unit time (ΔR/TUS) versus total length of bubble displacement, the three groups are fairly well-distinguished. (E & F) The third type, inertial (transient) cavitation, driven by short pulse and high pressure, led to the highest delivery efficiency with the highest delivery rate and reasonably high viability.
US: Ultrasound.
Reproduced with permission from [54].