Utilizing nonlinear behavior of microbubbles in medical ultrasound

Microbubbles exposed to ultrasound exhibit extremely nonlinear conspicuous behaviors. Medical imaging makes wide use of the pulse inversion method, in which only this nonlinear component is extracted by adding the received signals obtained by sending the phase inverted ultrasonic pulses twice. Further, there have been research efforts to use this nonlinear behavior for sonochemical healing of tumors by the efficient generation of acoustic cavitation by illumination with the second harmonic superimposed on the fundamental wave. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 90(8): 63–69, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20259