Patient-specific flow analysis of brain aneurysms at a single location: Comparison of hemodynamic characteristics in small aneurysms

Division of Interventional Neuroradiology, David Geffen School of Medicine, University of California, 10833 LeConte Ave., Box 951721, Los Angeles, CA 90095, USA.
Medical & Biological Engineering (Impact Factor: 1.73). 10/2008; 46(11):1113-20. DOI: 10.1007/s11517-008-0400-5
Source: PubMed


The purpose of this study is to examine and compare the hemodynamic characteristics of small aneurysms at the same anatomical location. Six internal carotid artery-ophthalmic artery aneurysms smaller than 10 mm were selected. Image-based computational fluid dynamics (CFD) techniques were used to simulate aneurysm hemodynamics. Flow velocity and wall shear stress (WSS) were also quantitatively compared, both in absolute value and relative value using the parent artery as a baseline. We found that flow properties were similar in ruptured and unruptured small aneurysms. However, the WSS was lower at the aneurysm site in unruptured aneurysms and higher in ruptured aneurysms (P < 0.05). Hemodynamic analyses at a single location with similar size enabled us to directly compare the hemodynamics and clinical presentation of brain aneurysms. The results suggest that the WSS in an aneurysm sac can be an important hemodynamic parameter related to the mechanism of brain aneurysm growth and rupture.

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Available from: Aichi Chien, Dec 10, 2014
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    • "In aneurysms, areas of stasis can be observed in particular at sites close to the dome: the histological changes induced by local stagnation could lead to aneurysm growth and possibly subsequent rupture, since decreased wall shear stress is associated with inflammation and endothelial cell dysfunction. In addition, by using patient-based data to reconstruct aneurysms, computational fluid dynamic studies have exhibited considerable interindividual variability which is accompanied by different hemodynamic profiles [87] [88] [89] [90]. Therefore, it is challenging to discern the exact hemodynamic conditions inciting growth and predisposing these lesions to rupture. "
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    • "The 3D voxel data obtained by rotational angiography were then transferred to a Dell 490 hemodynamic analysis workstation in our division. Image-based computational fluid dynamics (CFD) software developed by the Department of Computational Sciences, George Mason University, was utilized for aneurysm flow simulation [6, 7]. The 3D computational model was constructed semiautomatically through segmentation, surface generation, and 3D grid generation for each ICA–Oph aneurysm. "
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