TY - JOUR
T1 - Ultrasound-Driven Microbubble Oscillation and Translation Within Small Phantom Vessels
AU - Zheng, Hairong
AU - Dayton, Paul A.
AU - Caskey, Charles
AU - Zhao, Shukui
AU - Qin, Shengping
AU - Ferrara, Katherine W.
PY - 2007/12
Y1 - 2007/12
N2 - The use of ultrasound radiation force to manipulate microbubbles in blood vessels has attracted recent interest as a method to increase the efficiency of ultrasonic molecular imaging and drug delivery. However, recent studies indicate that microbubble oscillation is diminished within small blood vessels, and therefore we investigate microbubble oscillation and translation within 12 μm vessels using high-speed photography. With each 0.1- to 1-MPa ultrasound pulse, microbubbles (radius of 1, 1.5 and 2 μm) within 12 μm tubes translate 5 to 10 times less than those within 200 μm tubes. Application of a pulse train with a high pulse repetition frequency displaces bubbles to the wall of 12- and 200-μm tubes within an interval (∼1 s) that is reasonable for clinical translation. Modeling of coupled oscillation and translation for unconstrained microbubbles, based on a modified Rayleigh-Plesset (RP) and the trajectory equations, is compared with experimental observations and demonstrates agreement for the larger displacements observed within the 200 μm tubes. This study has implications for contrast-assisted ultrasound applications, aiding the manipulation of targeted microbubbles and for further theoretical understanding of the complex bubble dynamics within constrained vessel. (E-mail: kwferrara@ucdavis.edu).
AB - The use of ultrasound radiation force to manipulate microbubbles in blood vessels has attracted recent interest as a method to increase the efficiency of ultrasonic molecular imaging and drug delivery. However, recent studies indicate that microbubble oscillation is diminished within small blood vessels, and therefore we investigate microbubble oscillation and translation within 12 μm vessels using high-speed photography. With each 0.1- to 1-MPa ultrasound pulse, microbubbles (radius of 1, 1.5 and 2 μm) within 12 μm tubes translate 5 to 10 times less than those within 200 μm tubes. Application of a pulse train with a high pulse repetition frequency displaces bubbles to the wall of 12- and 200-μm tubes within an interval (∼1 s) that is reasonable for clinical translation. Modeling of coupled oscillation and translation for unconstrained microbubbles, based on a modified Rayleigh-Plesset (RP) and the trajectory equations, is compared with experimental observations and demonstrates agreement for the larger displacements observed within the 200 μm tubes. This study has implications for contrast-assisted ultrasound applications, aiding the manipulation of targeted microbubbles and for further theoretical understanding of the complex bubble dynamics within constrained vessel. (E-mail: kwferrara@ucdavis.edu).
KW - Microvessel
KW - Oscillation
KW - Translation
KW - Ultrasound contrast microbubbles
KW - Ultrasound radiation force
UR - http://www.scopus.com/inward/record.url?scp=36849093332&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=36849093332&partnerID=8YFLogxK
U2 - 10.1016/j.ultrasmedbio.2007.06.007
DO - 10.1016/j.ultrasmedbio.2007.06.007
M3 - Article
C2 - 17900793
AN - SCOPUS:36849093332
VL - 33
SP - 1978
EP - 1987
JO - Ultrasound in Medicine and Biology
JF - Ultrasound in Medicine and Biology
SN - 0301-5629
IS - 12
ER -