Authors: Trung B Le Daniel R Troolin Devesh Amatya Ellen K Longmire Fotis Sotiropoulos
Publish Date: 2013/04/20
Volume: 41, Issue: 10, Pages: 2157-2170
Abstract
We carry out highresolution laboratory experiments and numerical simulations to investigate the dynamics of unsteady vortex formation across the neck of an anatomic in vitro model of an intracranial aneurysm A transparent acrylic replica of the aneurysm is manufactured and attached to a pulse duplicator system in the laboratory Timeresolved threedimensional threecomponent velocity measurements are obtained inside the aneurysm sac under physiologic pulsatile conditions Highresolution numerical simulations are also carried out under conditions replicating as closely as possible those of the laboratory experiment Comparison of the measured and computed flow fields shows very good agreement in terms of instantaneous velocity fields and threedimensional coherent structures Both experiments and numerical simulations show that a welldefined vortical structure is formed near the proximal neck at early systole This vortical structure is advected by the flow across the aneurysm neck and impinges on the distal wall The results underscore the complexity of aneurysm hemodynamics and point to the need for integrating highresolution timeresolved threedimensional experimental and computational techniques The current work emphasizes the importance of vortex formation phenomena at aneurysmal necks and reinforces the findings of previous computational work and recent clinical studies pointing to links between flow pulsatility and aneurysm growth and ruptureFinancial support for this work is from a grant from Mayo Clinic We would like to thank Dr David Kallmes for providing us the anatomic aneurysm geometry We gratefully acknowledge the support of Minnesota Supercomputing Institute for the computational time The first author Trung Bao Le is supported partially by a predoctoral fellowship from Vietnam Education Foundation
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