Automatic Detection and Visualization of Qualitative Hemodynamic Characteristics in Cerebral Aneurysms

Abstract

Cerebral aneurysms are a pathological vessel dilatation that bear a high risk of rupture. For the understanding and evaluation of the risk of rupture, the analysis of hemodynamic information plays an important role. Besides quantitative hemodynamic information, also qualitative flow characteristics, e.g., the inflow jet and impingement zone are correlated with the risk of rupture. However, the assessment of these two characteristics is currently based on an interactive visual investigation of the flow field, obtained by computational fluid dynamics (CFD) or blood flow measurements. We present an automatic and robust detection as well as an expressive visualization of these characteristics. The detection can be used to support a comparison, e.g., of simulation results reflecting different treatment options. Our approach utilizes local streamline properties to formalize the inflow jet and impingement zone. We extract a characteristic seeding curve on the ostium, on which an inflow jet boundary contour is constructed. Based on this boundary contour we identify the impingement zone. Furthermore, we present several visualization techniques to depict both characteristics expressively. Thereby, we consider accuracy and robustness of the extracted characteristics, minimal visual clutter and occlusions. An evaluation with six domain experts confirms that our approach detects both hemodynamic characteristics reasonably.

Cluster Analysis of Vortical Flow in Simulations of Cerebral Aneurysm Hemodynamics

“…Most techniques decompose a blood flow field into regions of similar behavior based on integral curves [2,17,23,32]. Others employ local vectors [47] or aneurysm wall properties [14,18,30].…”

“…Computational fluid dynamic (CFD) simulations of blood flow play a crucial role in understanding aneurysm rupture and evaluating its risk since they provide insights into the aneurysm hemodynamics [4,7,17]. Hemodynamic parameters are evaluated as predictors for aneurysm rupture together with geometrical descriptors, wall properties, inflammatory effects, genetic predispositions, and behavioral factors.…”

Blood Flow Clustering and Applications inVirtual Stenting of Intracranial Aneurysms

“…Streamlines at cluster boundaries are displayed as representatives. Gasteiger et al employ local streamline properties to identify and group lines that constitute the inflow jet, which is correlated with aneurysm rupture [31]. R€ ossl and Theisel discuss a spectral embedding of streamlines [11].…”

Inflow Jet Patterns of Unruptured Cerebral Aneurysms Based on the Flow Velocity in the Parent Artery: Evaluation Using 4D Flow MRI

“…1,2 Computational fluid dynamics analyses by using human cerebral aneurysm models suggested that inflow jets may be related to bleb formation and aneurysmal rupture. [3][4][5] Cebral et al 3 reported that most blebs formed at sites where the inflow jet impacted the aneurysmal wall, and they qualitatively classified the inflow jets of ruptured and unruptured cerebral aneurysms into concentrated and diffuse inflow jets.…”