Sensitivity of Blood Flow in Stenosed Carotid Bifurcation

I. LARRABIDE; P. J. BLANCO; S. URQUIZA; R. A. FEIJÓO

Lisboa

Conferencia; II International Conference on Computational Bioengineering (ICCB2005); 2005

Instituto Superior Tecnico

It is well known that hemodynamic factors are strongly influenced by the arterial geometry. Combining computational fluid dynamics with three-dimensional medical data can be of valuable aid for studying blood flow characteristics in real geometries. In this manner it is possible to analyze the sensitivity of hemodynamic factors related to shape changes in vascular districts. In this work the quantification of these sensitivities for a carotid bifurcation with different degrees of stenosis was investigated. To this end a multidimensional 3D - 1D FEM model of the whole arterial tree is implemented. It comprises a 3D compliant model of the carotid bifurcation coupled with a 1D model for the remaining part of the arterial tree, which makes use of Windkessel models to implement boundary conditions at the arteries ends. With this approach, difficulties arising from the treatment of boundary conditions for the 3D model are naturally handled. As mentioned above, several carotid bifurcation geometries were analyzed. Three of them are based on a standard geometry and correspond to different degree of stenosis at the carotid sinus. A fourth model was obtained from a patient-speciffic angiography using different image segmentation and reconstruction techniques. Detailed flow patterns and other associated hemodynamic factors are provided for all these models. Finally, these data results are analyzed in order to determine how geometrical changes influence the hemodynamic conditions for each case studied.