Fig. 13.

Representative optical images from high-speed microscopy showing native Definity bubble activity during first burst of 5 ms pulsing scheme for different sonication pressures and channel diameters. Individual frames are delineated by vertical black lines and red shaded frames indicate frames acquired during ultrasound exposure. Channel boundaries are not indicated here due to scale, but can be seen in Fig. 10. Scale bars on the bottom rows represent 50 µm. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)