TY - GEN
T1 - Threshold behavior of vibrating microbubbles
AU - Emmer, M.
AU - Van Wamel, A.
AU - Goertz, D. E.
AU - Versluis, M.
AU - De Jong, N.
PY - 2006/12/1
Y1 - 2006/12/1
N2 - For individual phospholipid-coated microbubbles with a diameter smaller than 5 μm, highspeed camera recordings revealed threshold behavior in the onset of vibration. Previous studies showed a pressure-dependent attenuation for phospholipid-coated microbubbles. The aim of this study was to investigate if there is a relationship between microbubble threshold behavior and pressure-dependent attenuation. At a rising acoustic pressure from 5 to 200 kPa, the attenuation of BR14 increased linearly from 4.5 dB to 7 dB. In contrast to BR14, Levovist did not show pressure-dependent attenuation. For BR14 smaller than 3 μm diameter, attenuation increased from 4 to 12 dB. However, up to 50 kPa no increase of attenuation was observed. These observations can be explained by phospholipid-coated bubble threshold behavior. When the acoustic pressure increases above a threshold acoustic pressure, microbubbles smaller than 5 μm start to oscillate and contribute to the attenuation. Levovist is considered to be a free microbubble, for which threshold behavior is not expected. An imaging technique such as power modulation imaging could profit from the presence of an acoustic pressure threshold.
AB - For individual phospholipid-coated microbubbles with a diameter smaller than 5 μm, highspeed camera recordings revealed threshold behavior in the onset of vibration. Previous studies showed a pressure-dependent attenuation for phospholipid-coated microbubbles. The aim of this study was to investigate if there is a relationship between microbubble threshold behavior and pressure-dependent attenuation. At a rising acoustic pressure from 5 to 200 kPa, the attenuation of BR14 increased linearly from 4.5 dB to 7 dB. In contrast to BR14, Levovist did not show pressure-dependent attenuation. For BR14 smaller than 3 μm diameter, attenuation increased from 4 to 12 dB. However, up to 50 kPa no increase of attenuation was observed. These observations can be explained by phospholipid-coated bubble threshold behavior. When the acoustic pressure increases above a threshold acoustic pressure, microbubbles smaller than 5 μm start to oscillate and contribute to the attenuation. Levovist is considered to be a free microbubble, for which threshold behavior is not expected. An imaging technique such as power modulation imaging could profit from the presence of an acoustic pressure threshold.
UR - http://www.scopus.com/inward/record.url?scp=48149099053&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2006.392
DO - 10.1109/ULTSYM.2006.392
M3 - Conference contribution
AN - SCOPUS:48149099053
SN - 1424402018
SN - 9781424402014
T3 - Proceedings - IEEE Ultrasonics Symposium
SP - 1545
EP - 1547
BT - 2006 IEEE International Ultrasonics Symposium, IUS
ER -