title: Emerging fractal patterns in a real 3D cerebral aneurysm.
abstract: The behaviour of biological fluid flows is often investigated in medical practice to draw conclusions on the physiological or pathological conditions of the considered organs. One area where such investigations are proven to be useful is the flow-related formation and growth of different pathologic malformations of the cerebro-vascular system. In this work, a detailed study is presented on the effect of a cerebral aneurysm on blood transport inside a human brain artery segment. This malformation causes strong flow instabilities that drives the flow system towards chaotic behaviour. The emerging fractal structure and some of its measurable properties have been explored using a method that makes the measurement of these properties feasible even in complicated large three dimensional data sets. We find that, from the investigated chaos parameters, the information dimension turns out to be the most reliable parameter to characterise chaotic advection in the vicinity of the aneurysm sac. We propose that properties of chaotic mixing close to aneurysms might be relevant for the condition of this pathologic malformation.
authors.affiliation: Department of Hydrodynamics Systems, Faculty of Mechanical Engineering, Budapest University of Technology and Economy, Műegyetem rakpart 3, 1111 Budapest, Hungary. Electronic address: zavodszky@hds.bme.hu.
authors.forename: Gábor
authors.initials: G
authors.lastname: Závodszky
authors.affiliation: Institute of Nuclear Techniques, Budapest University of Technology and Economy, Műegyetem rakpart 3, 1111 Budapest, Hungary. Electronic address: karolyi@reak.bme.hu.
authors.forename: György
authors.initials: G
authors.lastname: Károlyi
authors.affiliation: Department of Hydrodynamics Systems, Faculty of Mechanical Engineering, Budapest University of Technology and Economy, Műegyetem rakpart 3, 1111 Budapest, Hungary. Electronic address: paal@hds.bme.hu.
authors.forename: György
authors.initials: G
authors.lastname: Paál
mesh_terms: D002533:Cerebral Angiography; D003198:Computer Simulation; D017709:Fractals; D018056:Hemorheology; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics; D014057:Tomography, X-Ray Computed
keywords: CFD; Chaotic advection; Information dimension