ACOUSTIC FOUNTAINS IN LIQUIDS AND BIOLOGICAL TISSUE

Author: Oleg Sapozhnikov
Summary: When a focused ultrasound wave of moderate or high intensity in liquid encounters an air interface, a liquid jet emerges from the liquid surface to form what is known as an acoustic fountain. Atomization, or the emission of micro-droplet jets, occurs when the acoustic intensity exceeds a liquid-dependent threshold. It turned out that this effect is related to the recently proposed method of mechanical fractionation of soft biological tissue by HIFU in a process termed boiling histotripsy, wherein the focused ultrasound wave superheats the tissue at the focus, producing a millimeter-size boiling or vapor bubble in several milliseconds. Our hypothesis is that tissue can behave as a liquid such that it forms a fountain and atomization within the vapor bubble produced in boiling histotripsy. High-speed videography was used to observe the formation and atomization of fountains composed of water and other liquids. Similar phenomena were observed in tissues, and, as was shown, they caused erosion of tissue.
Time:11:00
Place:Salle de réunion du LabTAU, INSERM 151 Cours A.Thomas , Lyon