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Validation of CFD Simulations of Cerebral Aneurysms With Implication of Geometric Variations

Yiemeng Hoi
2006 Journal of Biomechanical Engineering  
This study aimed at validating the CFD methodology for studying cerebral aneurysms by using particle image velocimetry (PIV) measurements, with a focus on the effects of small geometric variations in aneurysm  ...  We further performed CFD analysis on two geometric variations, S2 and S3, of the phantom to investigate the effects of small geometric variations on the aneurysmal flow field. Results.  ...  ., and Rekha Tranquebar for assistance in image reconstruction, Lujie Cao for assistance in PIV measurements and Joanne Smith for assistance in editing.  ... 
doi:10.1115/1.2354209 pmid:17154684 pmcid:PMC2754174 fatcat:r4gfsvkwgfbrxjmdnjq3rpqf6m

Study of Extracted Geometry Effect on Patient-Specific Cerebral Aneurysm Model with Different Threshold Coefficient (Cthres)

Lim Sheh Hong, Mohd Azrul Hisham Mohd Adib, Mohd Shafie Abdullah, Nur Hartini Mohd Taib, Radhiana Hassan, Azian Abd Aziz
2020 CFD Letters  
Several threshold coefficients, Cthres such as 0.2, 0.3, 0.4, 0.5 and 0.6 were employed in the image segmentation creating three-dimensional (3D) realistic arterial geometries that were then used for CFD  ...  The recent diagnostic assessment of cerebrovascular disease makes use of computational fluid dynamics (CFD) to quantify blood flow and determine the hemodynamics factors contributing to the disease from  ...  Besides, CFD simulation is not able to validate in vivo hemodynamics accurately and precisely [3, 11, 43] .  ... 
doi:10.37934/cfdl.12.10.114 fatcat:wal4wakbzzed7bpp2xzzln3up4

Patient-Specific Cerebral Aneurysm Hemodynamics: Comparison of in vitro Volumetric Particle Velocimetry, Computational Fluid Dynamics (CFD), and in vivo 4D Flow MRI [article]

Melissa C. Brindise, Sean Rothenberger, Benjamin Dickerhoff, Susanne Schnell, Michael Markl, David Saloner, Vitaliy L. Rayz, Pavlos P. Vlachos
2019 arXiv   pre-print
These results suggest a need for further multi-modality analysis as well as development of non-dimensional hemodynamic parameters and correlation of such metrics to aneurysm risk of growth and rupture.  ...  Typical approaches to patient-specific hemodynamic studies of cerebral aneurysms use image based computational fluid dynamics (CFD) and seek to statistically correlate parameters such as wall shear stress  ...  For example, segmentation uncertainties among the in vitro and in silico data sets, the laminar flow assumptions used in CFD simulations, and the curved extension of the inflow vessel required for experimental  ... 
arXiv:1903.01303v1 fatcat:ysqzaz7pgjg6bnv6wexzyr2sza

Qualitative comparison of intra-aneurysmal flow structures determined from conventional and virtual angiograms

Juan R. Cebral, Alessandro Radaelli, Alejandro Frangi, Christopher M. Putman, Armando Manduca, Xiaoping P. Hu
2007 Medical Imaging 2007: Physiology, Function, and Structure from Medical Images  
Patient-specific CFD models were then constructed from 3D rotational angiography images of each aneurysm.  ...  In this study we qualitatively compare the flow structures observed in cerebral aneurysms using conventional angiography and virtual angiograms produced from patient-specific computational fluid dynamics  ...  ACKNOWLEDGEMENTS We thank Philips Medical Systems and the American Heart Association for financial support.  ... 
doi:10.1117/12.709231 fatcat:3xoigqcfdncybh244krwhsn2ki

Image-based computational simulation of flow dynamics in a giant intracranial aneurysm

David A Steinman, Jaques S Milner, Chris J Norley, Stephen P Lownie, David W Holdsworth
2003 American Journal of Neuroradiology  
Such image-based CFD analysis may be used to provide key hemodynamic information for prospective studies of aneurysm growth and rupture or to predict the response of an individual aneurysm to therapeutic  ...  This and a representative flow rate waveform were provided as boundary conditions for finite element CFD simulation of the 3D pulsatile velocity field.  ...  CFD models of cerebral aneurysms.  ... 
pmid:12695182 pmcid:PMC8148673 fatcat:lz2fzqrrmfagperhr2okrmlegy

Hemodynamics of Cerebral Aneurysms: Connecting Medical Imaging and Biomechanical Analysis

Vitaliy L Rayz, Aaron A Cohen-Gadol
2020 Annual Review of Biomedical Engineering  
Possible future directions include novel approaches enabling data assimilation and multimodality analysis of cerebral aneurysm hemodynamics.  ...  This review presents the state of the art in cerebral aneurysm imaging and image-based modeling, discussing the advantages and limitations of each approach and focusing on the translational value of hemodynamic  ...  hemodynamics and can serve as benchmark data for CFD validation.  ... 
doi:10.1146/annurev-bioeng-092419-061429 pmid:32212833 fatcat:jrvzsszb5vcwjfxbwhctafqvoq

Understanding the Role of Hemodynamics in the Initiation, Progression, Rupture, and Treatment Outcome of Cerebral Aneurysm from Medical Image-Based Computational Studies

Marcelo A. Castro
2013 ISRN Radiology  
for computational fluid and solid dynamics solvers and data analysis and visualization techniques.  ...  About a decade ago, the first image-based computational hemodynamic studies of cerebral aneurysms were presented.  ...  The author worked at the Center for Computational  ... 
doi:10.5402/2013/602707 pmid:24967285 pmcid:PMC4045510 fatcat:trwtozjzfbbhvgxk2qht6ym2ym

Multi-modality cerebral aneurysm haemodynamic analysis: in vivo 4D flow MRI, in vitro volumetric particle velocimetry and in silico computational fluid dynamics

Melissa C. Brindise, Sean Rothenberger, Benjamin Dickerhoff, Susanne Schnell, Michael Markl, David Saloner, Vitaliy L. Rayz, Pavlos P. Vlachos
2019 Journal of the Royal Society Interface  
These results suggest a need for further multi-modality analysis as well as development of non-dimensional haemodynamic parameters and correlation of such metrics to aneurysm risk of growth and rupture  ...  Typical approaches to patient-specific haemodynamic studies of cerebral aneurysms use image-based computational fluid dynamics (CFD) and seek to statistically correlate parameters such as wall shear stress  ...  Uncertainty quantification methods are widely available for PIV but have yet to be reported for STB and are needed so these datasets can be used as robust validation test cases for CFD simulations.  ... 
doi:10.1098/rsif.2019.0465 pmid:31506043 pmcid:PMC6769317 fatcat:in44s7fayvakpcb3yuj6bhikjm

Basic Fluid Dynamics and Tribia Related to Flow Diverter

Masaaki Shojima
2017 Journal of Neuroendovascular Therapy  
To enrich our understanding of endovascular treatment of cerebral aneurysm in the era of flow diverters (FD), related literature dealing with fluid dynamic engineering is reviewed and elaborated on here  ...  Blood flow simulation for FD is not easy but it would provide useful information for selecting the proper cases for FD as well as selecting the proper devices for a certain case.  ...  Now, CFD, a technique of computer-assisted simulation of the blood flow in cerebral aneurysms, is increasingly accepted (in silico).  ... 
doi:10.5797/jnet.ra-diverter.2016-0012 fatcat:ovbqwsfvj5ci7jgdodeoby64nu

Efficient pipeline for image-based patient-specific analysis of cerebral aneurysm hemodynamics: technique and sensitivity

J.R. Cebral, M.A. Castro, S. Appanaboyina, C.M. Putman, D. Millan, A.F. Frangi
2005 IEEE Transactions on Medical Imaging  
In this paper, an efficient methodology for patient-specific modeling and characterization of the hemodynamics in cerebral aneurysms from medical images is described.  ...  Index Terms-Cerebral aneurysm, computational fluid dynamics, rotational angiography, sensitivity.  ...  Sensitivity analysis is a useful method of understanding the interaction of variables used for the CFD process but does not supplant the need for validation of the CFD models using in vitro, animal and  ... 
doi:10.1109/tmi.2005.844159 pmid:15822804 fatcat:casie7ttyrdvbopaavopmobfsm

Computational and experimental studies into the hemodynamics of cerebral aneurysms

2016 Journal of Biomechanical Science and Engineering  
properties of vessel walls, as well as boundary conditions for CFD simulations.  ...  Rupture of cerebral aneurysms (CAs) is a major cause of life-threatening subarachnoid hemorrhage. It is still difficult to predict CA rupture since little is known about the risk factors.  ...  Miura et al. performed CFD analysis for 106 middle cerebral artery (MCA) aneurysms (43 ruptured, 63 unruptured) reconstructed from 3D rotational angiography images, comparing morphological and hemodynamic  ... 
doi:10.1299/jbse.15-00488 fatcat:nio5xxqim5e33pieuxdygk6afe

State-of-the-art Computational Models of Circle of Willis with Physiological Applications: a Review

Haipeng Liu, Defeng Wang, Xinyi Leng, Dingchang Zheng, Fei Chen, Lawrence Ka Sing Wong, Lin Shi, Thomas Wai Hong Leung
2020 IEEE Access  
risks such as aneurysms, ischemia, and atherosclerotic plaque growth.  ...  Secondly, the improvement of CoW models relies on the large-scale validations and the combination of various innovative modeling techniques.  ...  This model is potential for clinical use but needs further validation using in-vivo data. Finally, in-vitro experimental models of the CoW have been proposed.  ... 
doi:10.1109/access.2020.3007737 fatcat:cd3xqg6hobai5jkacz4kph3rv4

Comparison of existing aneurysm models and their path forward

John Friesen, Jonas Bergner, Mohammad Ibrahim Aftab Khan, Stefan Triess, Andreas Zoll, Peter F. Pelz, Farzin Adili
2021 Computer Methods and Programs in Biomedicine Update  
for research and clinical use is given  A detailed analysis of the known mechanisms behind aneurysms growth is given  Four different methods were identified: finite element analysis, fluid dynamics,  ...  aneurysms and abdominal aortic aneurysms , accounting together for over 80% of all fatal aneurysm incidences.  ...  The meta-analysis shows that CFD modeling plays a major role for the modeling of cerebral aneurysms, whereas FEA is primarily relevant for aortic 190 aneurysms.  ... 
doi:10.1016/j.cmpbup.2021.100019 fatcat:vy4dt4wlmfar5augmpjg2yr73q

In vivo visualization and analysis of 3-D hemodynamics in cerebral aneurysms with flow-sensitized 4-D MR imaging at 3 T

Stephan Meckel, Aurelien F. Stalder, Francesco Santini, Ernst-Wilhelm Radü, Daniel A. Rüfenacht, Michael Markl, Stephan G. Wetzel
2008 Neuroradiology  
The purpose of this study was to evaluate the feasibility of in vivo flow-sensitized 4-D MR imaging for analysis of intraaneurysmal hemodynamics.  ...  Introduction Blood-flow patterns and wall shear stress (WSS) are considered to play a major role in the development and rupture of cerebral aneurysms.  ...  Conflict of interest statement We declare that we have no conflict of interest.  ... 
doi:10.1007/s00234-008-0367-9 pmid:18350286 fatcat:gkm4ebcpq5gczcwrkdu7ifcrtq

Tetrahedral vs. polyhedral mesh size evaluation on flow velocity and wall shear stress for cerebral hemodynamic simulation

Martin Spiegel, Thomas Redel, Y. Jonathan Zhang, Tobias Struffert, Joachim Hornegger, Robert G. Grossman, Arnd Doerfler, Christof Karmonik
2011 Computer Methods in Biomechanics and Biomedical Engineering  
Haemodynamic factors, in particular wall shear stresses (WSSs) may have significant impact on growth and rupture of cerebral aneurysms.  ...  With increasing interest in integrating these CFD simulations into pretreatment planning, a better understanding of the validity of the calculations in respect to computation parameters such as volume  ...  Acknowledgements The authors would like to thank Dr Ralf Kroeger (ANSYS Germany Inc.) for his advice and simulation support.  ... 
doi:10.1080/10255842.2010.518565 pmid:21161794 fatcat:2qytops5xzelnmbghgkrletpmq
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