Intracranial stents being modeled as a porous medium: flow simulation in stented cerebral aneurysms

Article Article scientifique Article Intracranial stents being modeled as a porous medium: flow simulation in stented cerebral aneurysms eng 2011 author Augsburger Lucas 619797 author Reymond Philippe 0000-0002-0772-6862 729770 author Rufenacht D A author Stergiopulos N 850-863 10.1007/s10439-010-0200-6 21042856 0090-6964 https://link.springer.com/article/10.1007/s10439-010-0200-6 Intracranial aneurysms may be treated by flow diverters, alternatively to stents and coils combination. Numerical simulation allows the assessment of the complex nature of aneurismal flow. Endovascular devices present a rather dense and fine strut network, increasing the complexity of the meshing. We propose an alternative strategy, which is based on the modeling of the device as a porous medium. Two patient-specific aneurysm data sets were reconstructed using conventional clinical setups. The aneurysms selection was done so that intra-aneurismal flow was shear driven in one and inertia driven in the other. Stents and their porous medium analog were positioned at the aneurysm neck. Physiological flow and standard boundary conditions were applied. The comparison between both approaches was done by analyzing the velocity, vorticity, and shear rate magnitudes inside the aneurysm as well as the wall shear stress (WSS) at the aneurysm surface. Simulations without device were also computed. The average flow reduction reaches 76 and 41% for the shear and inertia driven flow models, respectively. When comparing the two approaches, results show a remarkable similarity in the flow patterns and magnitude. WSS, iso-velocity surfaces and velocity on a trans-sectional plane are in fairly good agreement. The root mean squared error on the investigated parameters reaches 20% for aneurysm velocity, 30.6% for aneurysm shear rate, and 47.4% for aneurysm vorticity. It reaches 20.6% for WSS computed on the aneurysm surface. The advantages of this approach reside in its facility to implement and in the gain in computational time. Results predicted by the porous medium approach compare well with the real stent geometry model and allow predicting the main effects of the device on intra-aneurismal flow, facilitating thus the analysis. Blood Vessel Prosthesis Cerebrovascular Circulation Computer Simulation Computer-Aided Design Equipment Design Equipment Failure Analysis Humans Intracranial Aneurysm/physiopathology/surgery Models, Cardiovascular Porosity Stents Dewey 616.8 61 Département des neurosciences cliniques 226 false Annals of Biomedical Engineering 39 2 cfc7a2d4-b488-484c-a5ec-986f74d26ceb Article (Published version) Restricted Augsburger2011_Article_IntracranialStentsBeingModeled.pdf 1180073 application/pdf restrictedAccess Faculté de médecine / Section de médecine clinique / Département des neurosciences cliniques

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Intracranial stents being modeled as a porous medium: flow simulation in stented cerebral aneurysms	Annals of Biomedical Engineering			2011	229	0

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Augsburger, Lucas