Loading in 2 Seconds...
Loading in 2 Seconds...
Gas Embolotherapy: Vascular Microbubbles for Cancer Treatment Joseph L. Bull, Brijesh Eshpuniyani, Andres J. Calderon, Tao Ye, and J. Brian Fowlkes Department of Biomedical Engineering The University of Michigan [email protected] http://www.umich.edu/~joebull. Introduction.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Joseph L. Bull, Brijesh Eshpuniyani, Andres J. Calderon, Tao Ye, and J. Brian Fowlkes
Department of Biomedical Engineering
The University of Michigan
For more details, see: Bull J.L. Critical Reviews in Biomedical Engineering 33(4): 299-346, 2005.
Rigid Tube Wall
Flexible Tube Wall
t (dimensionless) = 0, 0.4, 0.8, 1.2, 1.6, 2, time scale = 10.5 μs
Objective: determine effects of flow rate, bubble size, and gravity on splitting ratio of the bubble in a single bifurcation
Calderón A.J., Fowlkes J.B., and Bull J.L. Bubble splitting in bifurcating tubes: a model study of cardiovascular gas emboli transport. Journal of Applied Physiology, 99: 479-487, 2005.
Experiments θ = 0° □, θ = 15° Δ, θ = 30° ○, θ = 45° ◊, θ = 60° , θ = 90° . Theory θ = 0° ―――, θ = 15° ―― ――, θ = 30° ―― – ―― , θ = 45° …, θ = 60° ――― ―――, θ = 90° ―― – – ――.
Experiments θ = 0° □, θ = 5° Δ, θ = 10° , θ = 15° , θ = 20° ◊, θ = 30° . Theory θ = 0° ―――, θ = 5° ―― ――, θ = 10° ―― – ―― , θ = 15° …, θ = 20° ――― ―――, θ = 30° ―― – – ――.
Bubble size relative to vessel size affects splitting behavior
Theory captures behavior of experiments
Resolved apparent paradox between Chang et al. and Souders et al. studies
Acoustic droplet vaporization in small vessels could potentially lead to even distribution of microbubbles
Inertial, viscous, and surface tension forces are important—gravity doesn’t tell the whole story!Single Bifurcation Bubble Splitting Conclusions
Calderón A.J., Heo Y.S., Huh D., Futai N., Takayama S., Fowlkes J.B., and Bull J.L. A microfluidic model of bubble lodging in microvessel bifurcations. Applied Physics Letters, 89(24): Art. No. 244103, 2006.
Kripfgans OD, et al., IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control. 52(7): 1101-1110, 2005.