Title :
1B-5 Surface Modes of Ultrasound Contrast Agent Microbubbles
Author :
Van Der Meer, Sander M. ; Dollet, Benjamin ; Goertz, David E. ; De Jong, Nico ; Versluis, Michel ; Lohse, Detlef
Author_Institution :
Phys. of Fluids, Twente Univ., Enschede
Abstract :
We study non-spherical oscillations (surface modes) of the coated microbubbles used in ultrasound contrast agents. We show that an acoustic pressure of 100 kPa, at a frequency of 1.7 MHz, is sufficient to excite surface modes for radii between 2 and 4 mum. Surface modes develop as a parametric instability. We derive their evolution equation accounting for the effect of the shell viscoelasticity. We identify a critical radius (1 to 3 mum, depending on the mode number) below which no surface mode can occur
Keywords :
bubbles; ultrasonic imaging; viscoelasticity; 1.7 MHz; 100 kPa; acoustic pressure; coated microbubbles; evolution equation accounting; nonspherical oscillations; parametric instability; shell viscoelasticity; surface mode; ultrasound contrast agent; Acoustic pulses; Acoustic scattering; Elasticity; Frequency; Optical fibers; Optical microscopy; Optical scattering; Optical surface waves; Ultrasonic imaging; Viscosity;
Conference_Titel :
Ultrasonics Symposium, 2006. IEEE
Conference_Location :
Vancouver, BC
Print_ISBN :
1-4244-0201-8
Electronic_ISBN :
1051-0117
DOI :
10.1109/ULTSYM.2006.41
