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

Abstract

Abstract-Hemodynamic factors are thought to be implicated in the progression and rupture of intracranial aneurysms. Current efforts aim to study the possible associations of hemodynamic characteristics such as complexity and stability of intra-aneurysmal flow patterns, size and location of the region of flow impingement with the clinical history of aneurysmal rupture. However, there are no reliable methods for measuring blood flow patterns in vivo. In this paper, an efficient methodology for patient-specific modeling and characterization of the hemodynamics in cerebral aneurysms from medical images is described. A sensitivity analysis of the hemodynamic characteristics with respect to variations of several variables over the expected physiologic range of conditions is also presented. This sensitivity analysis shows that although changes in the velocity fields can be observed, the characterization of the intra-aneurysmal flow patterns is not altered when the mean input flow, the flow division, the viscosity model, or mesh resolution are changed. It was also found that the variable that has the greater impact on the computed flow fields is the geometry of the vascular structures. We conclude that with the proposed modeling pipeline clinical studies involving large numbers cerebral aneurysms are feasible.Index Terms-Cerebral aneurysm, computational fluid dynamics, rotational angiography, sensitivity.

Computational vascular fluid–structure interaction: methodology and application to cerebral aneurysms

“…In this work, the blood is modeled as a Newtonian fluid. Although the blood is generally considered to be a nonNewtonian fluid, it was shown in Cebral et al (2005) that the Newtonian assumption is sufficient for cerebral aneurysm flows.…”

Progress in the CFD Modeling of Flow Instabilities in Anatomical Total Cavopulmonary Connections

“…Conducting such studies and further down the line, applying them to patient-specific pre-surgical planning requires highperformance clinical computer clusters and an efficient model generation pipeline. 4 Few studies have reported on the efficacy and feasibility of parallel simulations for patient-specific modeling. Dong and coworkers have successfully distributed one large-scale patientspecific model to multiple long-distance international clusters through the TeraGrid consorsium.…”

Methodologies to assess blood flow in cerebral aneurysms: Current state of research and perspectives

“…The materials of vascular replicas have evolved and spatial resolution of 3D data improved stepwise, giving today possibilities to a range of model production reaching from simple idealized shapes up to complex, patient-specific cerebral aneurysm replicas based on three-dimensional rotational angiography (3D-RA) [14]. Using rapid prototyping (RP) technologies, 3D description of the aneurysm geometry serves to produce models made of transparent materials such as plexiglas (polymethyl-methacrylate), silicone or poly-vinyl-alcohol-hydrogel, (PVA-H).…”

“…The quality of medical images permits the reproduction of the cerebral geometry very precisely, so that intra-aneurismal flow can be simulated accurately. The combination of advanced image processing and geometrical modeling techniques with computational fluid dynamics enhanced the generation of detailed hemodynamical aneurismal flow in patient-specific geometries [14,28]. Cebral et al developed a CFD pipeline allowing for the computation of the arterial and aneurismal flow based on CTA and 3D rotational angiography image data.…”