Premium
An experimental model of cardiovascular microbubble lodging
Author(s) -
Calderon Andres Javier,
Heo Yunseok,
Nobuyuki Futai,
Takayama Shuichi,
Fowlkes J. Brain,
Bull Joseph L.
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a409-c
Subject(s) - bubble , mechanics , microchannel , flow (mathematics) , bifurcation , chemistry , tube (container) , materials science , arteriole , pressure drop , biomedical engineering , composite material , physics , medicine , microcirculation , radiology , quantum mechanics , nonlinear system
Motivated by a novel developmental gas embolotherapy aimed at treating renal and hepatocellular carcinoma and by air embolism, our objective was to elucidate the dynamics of cardiovascular microbubble lodging in model arteriole bifurcations. This gas embolotherapy technique involves introducing small encapsulated liquid perfluorocarbon droplets into the bloodstream, and selectively vaporizing them to form gas bubbles that are sufficiently large to lodge, occluding flow and inducing tumor necrosis. Microchannel model arteriole bifurcations were constructed from poly(dimethylsiloxane), PDMS, using soft lithography. A single long (compared to the vessel diameter) bubble was placed in the parent tube of a fluid‐filled single bifurcation or a bifurcating network. Flow through the model vessels was driven by an imposed pressure difference. Microparticles in the fluid were used for flow visualization and for determining if the model vessels were completely occluded. The maximum driving pressure for lodging and minimum driving pressure for dislodging of the bubble were measured. The effects bubble size, parent to daughter tube diameter ratios, and multiple bubbles (corresponding to multiple doses of emboli) were examined. Preliminary results indicate that longer bubbles lodge and dislodge at higher driving pressures. In the bifurcating networks, flow can be occluded at high (relative to physiologic values) pressures when several bubbles are present, even though flow is shunted away from the occluded regions of the bifurcating network. This work was supported by NIH Grant EB003541 and NSF Grant BES‐0301278.