22 Hits in 7.4 sec

Simulation of Intra-Aneurysmal Blood Flow by Different Numerical Methods

Frank Weichert, Lars Walczak, Denis Fisseler, Tobias Opfermann, Mudassar Razzaq, Raphael Münster, Stefan Turek, Iris Grunwald, Christian Roth, Christian Veith, Mathias Wagner
2013 Computational and Mathematical Methods in Medicine  
CFD is applied to assess flow and aneurysmal vorticity in 2D and 3D models.  ...  A result obtained from this analysis indicates that a combined use of the different numerical methods, LBM for fast exploration and FEM for a more in-depth look, may result in a better understanding of  ...  Acknowledgment The authors would like to offer their sincerest gratitude to the German Research Association (DFG), funding the project as part of FOR493 and TRR30, the Jindrich Necas Center for Mathematical Modeling  ... 
doi:10.1155/2013/527654 pmid:23662158 pmcid:PMC3639637 fatcat:av5gqymnwfbonjrp7nfhwxmn6i

Lattice Boltzmann Model of 3D Multiphase Flow in Artery Bifurcation Aneurysm Problem

Aizat Abas, N. Hafizah Mokhtar, M. H. H. Ishak, M. Z. Abdullah, Ang Ho Tian
2016 Computational and Mathematical Methods in Medicine  
Three different types of Lattice Boltzmann (LB) models are computed, namely, single relaxation time (SRT), multiple relaxation time (MRT), and regularized BGK models.  ...  This paper simulates and predicts the laminar flow inside the 3D aneurysm geometry, since the hemodynamic situation in the blood vessels is difficult to determine and visualize using standard imaging techniques  ...  Lattice Boltzmann Models The results shown in this section are formulated using D3Q19 lattice model.  ... 
doi:10.1155/2016/6143126 pmid:27239221 pmcid:PMC4864205 fatcat:ae6jlpy5fjce5no3wfgpn6hpem

An Automated Workflow for Hemodynamic Computations in Cerebral Aneurysms

Cosmin-Ioan Nita, Takashi Suzuki, Lucian Mihai Itu, Viorel Mihalef, Hiroyuki Takao, Yuichi Murayama, Puneet Sharma, Thomas Redel, Saikiran Rapaka
2020 Computational and Mathematical Methods in Medicine  
In recent years, computational fluid dynamics (CFD) has become a valuable tool for investigating hemodynamics in cerebral aneurysms.  ...  We propose a fully automated pipeline that covers the steps from a patient-specific anatomical model to results, based on a fast, graphics processing unit- (GPU-) accelerated CFD solver and a parameter  ...  A lower pressure loss coefficient was identified as a significant risk factor for the rupture of small intracranial aneurysms. Methods 2.1. The Lattice Boltzmann Method.  ... 
doi:10.1155/2020/5954617 pmid:32655681 pmcid:PMC7317611 fatcat:qfa3zygsj5fdlnsybl3yrcydke

Thrombosis in Cerebral Aneurysms and the Computational Modeling Thereof: A Review

Malebogo N. Ngoepe, Alejandro F. Frangi, James V. Byrne, Yiannis Ventikos
2018 Frontiers in Physiology  
This is then followed by a review of computational models of clotting in cerebral aneurysms, specifically.  ...  The aim of this review is to present the information so it will be of benefit to the community attempting to model cerebral aneurysm thrombosis for interventional planning purposes, in a simplified yet  ...  Below a shear rate of 100 s −1 , clotting is initiated and growth occurs. A Lattice Boltzmann method for hydrodynamics is used to compute hemodynamics in an idealized aneurysm geometry.  ... 
doi:10.3389/fphys.2018.00306 pmid:29670533 pmcid:PMC5893827 fatcat:ykjn4gegpvfojemzxlcglyv6rm

A Highly Automated Computational Method for Modeling of Intracranial Aneurysm Hemodynamics

Jung-Hee Seo, Parastou Eslami, Justin Caplan, Rafael J. Tamargo, Rajat Mittal
2018 Frontiers in Physiology  
Intracranial aneurysms manifest in a vast variety of morphologies and their growth and rupture risk are subject to patient-specific conditions that are coupled with complex, non-linear effects of hemodynamics  ...  In the present study, we develop a highly-automated method based on the immersed boundary method framework to construct computational models from medical imaging data which is the key idea is the direct  ...  The level-set function based methods have been used for the simulation of aneurysm hemodynamics on the Cartesian grid using a lattice Boltzmann method (LBM) (He et al., 2009; Závodszky and Paál, 2013  ... 
doi:10.3389/fphys.2018.00681 pmid:29946264 pmcid:PMC6005827 fatcat:qbakywvthrbhhbigwhosq67dou

Continuum model for flow diverting stents in 3D patient-specific simulation of intracranial aneurysms

Sha Li, Bastien Chopard, Jonas Latt
2019 Journal of Computational Science  
The purpose of a FDS is to modify the blood flow within the aneurysmal cavity and induce thrombosis and tissue remodeling.  ...  In this paper we develop a new screenbased model to represent FDS at a coarse scale, with local porosity.  ...  In particular, rupture of intracranial aneurysms is an event with a high mortality rate, and about one third of the survivors suffer from permanent neurological or cognitive deficits [3] .  ... 
doi:10.1016/j.jocs.2019.101045 fatcat:l5onfwp6qvgvjhw2bj4qx5utpe

Effect of Pulsatility on the Transport of Thrombin in an Idealized Cerebral Aneurysm Geometry

Struan Hume, Jean-Marc Ilunga Tshimanga, Patrick Geoghegan, Arnaud G. Malan, Wei Hua Ho, Malebogo N. Ngoepe
2022 Symmetry  
Computational models of cerebral aneurysm thrombosis are designed for use in research and clinical applications. A steady flow assumption is applied in many of these models.  ...  To explore the accuracy of this assumption a pulsatile-flow thrombin-transport computational fluid dynamics (CFD) model, which uses a symmetrical idealized aneurysm geometry, was developed.  ...  s intracranial aneurysm thrombosis model employing a lattice Boltzmann numerical algorithm, which applies a pulsatile pressure outlet to a comparable idealised large aneurysm [37] .  ... 
doi:10.3390/sym14010133 fatcat:s4rf2464njf7hobikhpf6zjdve

Wall orientation and shear stress in the lattice Boltzmann model

Maciej Matyka, Zbigniew Koza, Łukasz Mirosław
2013 Computers & Fluids  
In this work we present a simple formula to calculate the wall shear stress in the lattice Boltzmann model and propose to compute wall normals, which are necessary to compute the wall shear stress, by  ...  The lattice Boltzmann is an easily parallelizable numerical method of solving the flow problems, but it suffers from errors of the velocity field near the boundaries which leads to errors in the wall shear  ...  [4] , in a clinical study on the rupture risk assesment in the cerebral aneurysm [5] or in a discovery of a shear-driven mechanism of platelet aggregation in arterial thrombosis [6] .  ... 
doi:10.1016/j.compfluid.2012.12.018 fatcat:biesra3vuzgljhzo5qy2v5cbom

A new pseudo-spectral methodology without numerical diffusion for conducting dye simulations and particle residence time calculations [article]

Faisal Amlani, Heng Wei, Niema M. Pahlevan
2021 arXiv   pre-print
The methodology is applied to three distinct physical/physiological cases: 1) flow over a two-dimensional (2D) cavity; 2) pulsatile flow in a simplified partially-grafted aortic dissection model; and 3  ...  ) non-Newtonian blood flow in a Fontan graft.  ...  Kaxiras, A lattice boltzmann simulation of hemodynamics in a patient-specific aortic coarctation model, in: International Workshop on Statistical Atlases and Computational Models of the Heart  ... 
arXiv:2112.05257v1 fatcat:kssgdziilfg7zbg3mikqjhesry

Letter from the President of WFITN

2015 Interventional Neuroradiology  
More studies are needed before it applies for evaluating aneurysm rupture risk in clinical applications.  ...  Conclusion: We demonstrated the feasibility to study leukocyte transport phenomenon inside cerebral aneurysms by an image-based patient-specific CFD analysis.  ...  The CFD solver is based on the lattice Boltzmann method which is known to be a highly parallel numerical scheme.  ... 
doi:10.1177/1591019915618059 pmid:26547766 pmcid:PMC4757183 fatcat:fvlfbc5e3zac5l7gpae3qxtgzy


2006 Neuroradiology  
This stent appears to be a valuable alternative to ballon-expandable coronary stents. O10.4  ...  Neuroradiology (2006) 48 (Suppl 2): 57-135 Neuroradiology (2006 48 (Suppl 2): 57-135 CONCLUSION The use of the self-expanding Wingspan Stent for treatment of intracranial stenoses is technically feasible  ...  MATERIAL AND METHODS To simulate the haemodynamics, a two-dimensional (2D) Lattice Boltzmann model has been used.  ... 
doi:10.1007/s00234-006-0137-5 pmid:16932977 fatcat:sjmqiubb35gx7kxn4uofb732cq

Continuum model for flow diverting stents of intracranial aneurysms

Sha Li, Bastien Chopard, Jonas Latt
parent vessel [20] . • Sac thrombosis: clinical observations of broad-based saccular intracranial aneurysms show spontaneous sac thrombosis after stent placement [70, 68] .  ...  Introduction of Lattice Boltzmann method In the past two decades, the Lattice Boltzmann method(LBM) has gained popularity for the simulation of fluid in both engineering and academic fields.  ...  Appendices The generation of the stenthull This appendix provides a practical guide on the generation of the stent hull, as described in Section 4.4.1, using the open-source software MeshLab.  ... 
doi:10.13097/archive-ouverte/unige:115538 fatcat:njostprsijbclan7vywx5w4pxm

Hemodynamics and virtual stenting of cerebral aneurysms [article]

Santhosh Seshadhri, Universitäts- Und Landesbibliothek Sachsen-Anhalt, Martin-Luther Universität, Dominique Thévenin, Martin Skalej
Das Modell im Maßstab 1:1 besteht aus durchsichtigem Silikon.  ...  Dieses Kriterium liefert detaillierte Informationenüber den Volumenstrom, der in das Aneurysma eintritt.  ...  [96] described the clotting process in stented aneurysms using a lattice Boltzmann (LB) model, considering two types of aneurysm geometry, with the same neck size but with different aspect ratios.  ... 
doi:10.25673/5391 fatcat:7a5gxhthuzaunlxwdnbjytcnt4

Haemodynamic simulation and optimisation for the flow-diversion treatment of intracranial aneurysms

Mingzi Zhang
Despite various complications reported, flow-diverting (FD) stent implantation has become a major mode of treatment for intracranial aneurysms.  ...  Based upon this series of studies, a workflow was put forward to individualise the treatment plan corresponding to the haemodynamic characteristics of a specific patient, from the patient aneurysm model  ...  Recently, a mesoscopic method -the lattice Boltzmann method (LBM), which uses a discrete Boltzmann equation to solve the flow with collision models -has also been implemented [43] .  ... 
doi:10.25949/19427447.v1 fatcat:op6oox4s6rct5pytctyrofc4am

Multimodale Modellierung intravaskulärer Hämodynamik am Beispiel zerebraler Aneurysmen [article]

Philipp Berg, Universitäts- Und Landesbibliothek Sachsen-Anhalt, Martin-Luther Universität, Gábor Janiga
To gain the required knowledge with respect to intracranial aneurysm hemodynamics, numerical methods are increasingly used for evaluation and treatment optimization.  ...  However, it has been shown that their broad clinical acceptance is limited due to numerous model-based assumptions.  ...  This work was partly funded by the Federal Ministry of Education and Research in Germany within the Research Campus STIMULATE under Grant no. 13GW0095A.  ... 
doi:10.25673/36636 fatcat:smeiwt5xmrhulhwo7zzsg4dape
« Previous Showing results 1 — 15 out of 22 results