13 March 2008 Simulation of microbubble response to ambient pressure changes
Author Affiliations +
The theory on microbubbles clearly indicates a relation between the ambient pressure and the acoustic behavior of the bubble. The purpose of this study was to optimize the sensitivity of ambient pressure measurements, using the subharmonic component, through microbubble response simulations. The behaviour of two different contrast agents was investigated as a function of driving pulse and ambient overpressure, pov. Simulations of Levovist using a rectangular driving pulse show an almost linear reduction in the subharmonic component as pov is increased. For a 20 cycles driving pulse, a reduction of 4.6 dB is observed when changing pov from 0 to 25 kPa. Increasing the pulse duration makes the reduction even more clear. For a pulse with 64 cycles, the reduction is 9.9 dB. This simulation is in good correspondence with measurement results presented by Shi et al. 1999, who found a linear reduction of 9.6 dB. Further simulations of Levovist show that also the shape and the acoustic pressure of the driving pulse are very important factors. The best pressure sensitivity of Levovist was found to be 0.88 dB/kPa. For Sonazoid, a sensitivity of 0.71 dB/kPa has been found, although the reduction is not completely linear as a function of the ambient pressure.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Klaus Scheldrup Andersen, Klaus Scheldrup Andersen, Jørgen Arendt Jensen, Jørgen Arendt Jensen, "Simulation of microbubble response to ambient pressure changes", Proc. SPIE 6920, Medical Imaging 2008: Ultrasonic Imaging and Signal Processing, 692016 (13 March 2008); doi: 10.1117/12.773296; https://doi.org/10.1117/12.773296

Back to Top