Evaluation of time-dependent wall shear stress visualizations for cerebral aneurysms

Abstract

For the rupture risk assessment of cerebral aneurysms, the blood flow is approximated using computational fluid dynamics (CFD). Unsteady CFD inflow conditions yield time-dependent vector fields, from which the wall shear stress (WSS), an important indicator for rupture risk in clinical research, is extracted. For WSS evaluation, its magnitude is usually color-coded on the aneurysm surface mesh. Hence, time-dependent results would require an animated depiction of all WSS values. Instead, mostly a static 3D representation is employed by choosing a single point in time, e.g., peak-systole. Our developed framework comprises such a static WSS visualization, an animated visualization, as well as a new technique including statistic information. We compare them in a user study and match them against a ground truth extracted by a clinical expert. The new technique with statistical information turned out to be superior compared to the ground truth for the depiction of time-dependent WSS.