A Computational Hemodynamics Analysis on the Correlation Between Energy Loss and Clinical Outcomes for Flow Diverters Treatment of Intracranial Aneurysm

Abstract

Rupture of intracranial aneurysms might lead to permanent disability or even death. One possible endovascular treatment is to deploy flow diverters (FDs), reducing flow into the sac and promoting thrombosis. Computational fluid dynamics simulations were used to assess the flow patterns and dynamics. The concept of energy loss, as a measure of work done necessary to overcome flow resistance, will be utilized to correlate with clinical outcome. If a surgical operation is successful, the flow is diverted to a shorter path and energy loss should be reduced. Conversely, persistent flow in the sac associated with treatment failure will display increased energy loss, as blood is then squeezed through the stent pores. Four illustrative clinical cases, involving both bifurcation and sidewall aneurysms, were selected. To reduce the numerical complexity, earlier works in the literature had employed a porous medium approximation for the FDs. Here the FD was simulated explicitly as a virtual (or computer generated) stent which would likely provide a more accurate description. Furthermore, quantitative comparisons between the approaches of virtual stent and porous medium with typical parameters were conducted by examining the effective flow influx into the aneurysm.