Computational fluid dynamics using dual-layer porous media modeling to evaluate the hemodynamics of cerebral aneurysm treated with FRED: A technical note

Flow diverter (FD) implantation is increasingly performed for aneurysms that are difficult to treat with conventional endovascular therapy and direct surgery. Now, a new FD stent, the Flow-Redirection Endoluminal Device (FRED), enters into clinical practice and is expected to have higher therapeutic efficacy. To predict whether an aneurysm is completely occluded by FRED, we have developed a novel computational fluid dynamics (CFD) technique using dual-layer porous media modeling that simulates its characteristic stent strut. This technique may be useful to evaluate hemodynamic changes in an aneurysm after FRED implantation using the preoperative patient-specific aneurysm geometry. The authors describe the novel CFD technique with a dual-layer porous media and report the potential usefulness of the technique to predict the aneurysm-occlusion status after FRED implantation preoperatively using an illustrative case of an unruptured internal carotid artery anterior wall aneurysm.