Ultrasonically induced intravascular streaming and thrombus formation adjacent to a micropipette.

Ultrasonically induced microstreaming around bubbles of gas have been shown to cause damage to biological materials in vitro at clinical exposure levels. The potential for ultrasonically induced cavitation and microstreaming in mammalian systems is of interest with respect to the safe application of clinical ultrasound. Ultrasonically induced intravascular microstreaming and formation of thrombi at 1 MHz is demonstrated adjacent the tip of a micropipette in contact with a mesenteric vessel of the mouse. These effects occur at or above therapeutic levels.