Abstract
The number of scientific publications dealing with stented intracranial aneurysms is rapidly increasing. Powerful computational facilities are now available; an accurate computational modeling of hemodynamics in patient-specific configurations is, however, still being sought. Furthermore, there is still no general agreement on the quantities that should be computed and on the most adequate analysis for intervention support. In this article, the accurate representation of patient geometry is first discussed, involving successive improvements. Concerning the second step, the mesh required for the numerical simulation is especially challenging when deploying a stent with very fine wire structures. Third, the description of the fluid properties is a major challenge. Finally, a founded quantitative analysis of the simulation results is obviously needed to support interventional decisions. In the present work, an attempt has been made to review the most important steps for a high-quality computational fluid dynamics computation of virtually stented intracranial aneurysms. In consequence, this leads to concrete recommendations, whereby the obtained results are not discussed for their medical relevance but for the evaluation of their quality. This investigation might hopefully be helpful for further studies considering stent deployment in patient-specific geometries, in particular regarding the generation of the most appropriate computational model.
This work was financially supported in part by the International Max Planck Research School for Analysis, Design and Optimization in Chemical and Biomedical Process Engineering Magdeburg and the Land Saxony-Anhalt in Germany. The help of S. Seshadhri to produce the CAD geometry of the stent and to support the mesh generation is highly acknowledged. The permission to publish a case from the VISC challenge has been provided by the main organizer, Professor Makoto Ohta, and is warmly acknowledged.
Conflict of interest statement:
We declare that we have no conflict of interest.
References
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