TY - GEN
T1 - Radial modulation imaging of microbubbles at high frequency
AU - Chérin, E.
AU - Brown, J.
AU - Shariff, H.
AU - Karshafian, R.
AU - Williams, R.
AU - Burns, P. N.
AU - Foster, F. S.
AU - Måsøy, S. E.
PY - 2007
Y1 - 2007
N2 - In this paper, radial modulation imaging of microbubbles is investigated at high frequency. A modulation pulse frequency of 3.7 MHz with an amplitude ranging from 0 to 250 kPa, and a 1.3 MPa 20 MHz broadband imaging pulse were used. Radial modulation effects were observed on a population of flowing microbubbles and quantified using a Doppler-type processing technique. Artifact signals related to the generation of harmonics by bubbles strongly resonating at the modulation frequency were observed. The bubble response to simultaneous modulation and imaging excitations was simulated for different combinations of bubble sizes and modulation amplitudes. Simulations confirm the hypothesis that the generation of harmonics of the modulation frequency can be detected by the imaging transducer. Simulations indicate that the modulation frequency should be chosen lower than the resonant frequency of the biggest bubbles present in the population. The simulation also suggests that a 10-20% variation of bubble diameter induced by the modulation excitation is sufficient for radial modulation imaging. In conclusion, the effects of radial modulation are detectable at a high frequency. Therefore, radial modulation imaging has potential for high-resolution imaging of microbubbles in the microvasculature.
AB - In this paper, radial modulation imaging of microbubbles is investigated at high frequency. A modulation pulse frequency of 3.7 MHz with an amplitude ranging from 0 to 250 kPa, and a 1.3 MPa 20 MHz broadband imaging pulse were used. Radial modulation effects were observed on a population of flowing microbubbles and quantified using a Doppler-type processing technique. Artifact signals related to the generation of harmonics by bubbles strongly resonating at the modulation frequency were observed. The bubble response to simultaneous modulation and imaging excitations was simulated for different combinations of bubble sizes and modulation amplitudes. Simulations confirm the hypothesis that the generation of harmonics of the modulation frequency can be detected by the imaging transducer. Simulations indicate that the modulation frequency should be chosen lower than the resonant frequency of the biggest bubbles present in the population. The simulation also suggests that a 10-20% variation of bubble diameter induced by the modulation excitation is sufficient for radial modulation imaging. In conclusion, the effects of radial modulation are detectable at a high frequency. Therefore, radial modulation imaging has potential for high-resolution imaging of microbubbles in the microvasculature.
UR - http://www.scopus.com/inward/record.url?scp=48149100919&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=48149100919&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2007.227
DO - 10.1109/ULTSYM.2007.227
M3 - Conference contribution
AN - SCOPUS:48149100919
SN - 1424413834
SN - 9781424413836
T3 - Proceedings - IEEE Ultrasonics Symposium
SP - 888
EP - 891
BT - 2007 IEEE Ultrasonics Symposium Proceedings, IUS
T2 - 2007 IEEE Ultrasonics Symposium, IUS
Y2 - 28 October 2007 through 31 October 2007
ER -