Journal article
Ambient pressure sensitivity of microbubbles investigated through a parameter study
Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark1
Department of Electrical Engineering, Technical University of Denmark2
Biomedical Engineering, Department of Electrical Engineering, Technical University of Denmark3
Center for Fast Ultrasound Imaging, Centers, Technical University of Denmark4
Measurements on microbubbles clearly indicate 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 behavior of two microbubbles corresponding to 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 1.14 dB/kPa has been found, although the reduction is not completely linear as a function of the ambient pressure.
Language: | English |
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Publisher: | Acoustical Society of America |
Year: | 2009 |
Pages: | 3350-3358 |
ISSN: | 15208524 , 00014966 and 01630962 |
Types: | Journal article |
DOI: | 10.1121/1.3242359 |
ORCIDs: | Jensen, Jørgen Arendt |