Evaluation of intra-aneurysmal hemodynamics after flow diverter placement in a patient-specific aneurysm model.

Abstract

The growth and rupture of cerebral aneurysms is intrinsically related to the hemodynamics prevailing in the diseased area. Therefore, a better understanding of intra-aneurysmal hemodynamics is essential for developing effective treatment methods. The intention of this study was to evaluate the intra-aneurysmal flow and flow reduction induced by flow diverters in a true-to-scale elastic aneurysm model, obtained from real patient data. Based on the computed tomography angiography (CTA) data of a fusiform aneurysm of a 34 year old patient, an elastic silicon rubber model of the aneurysm was produced. A physiologic pulsatile flow was created with a circulatory experimental set-up, and a non-Newtonian perfusion fluid was used as a substitute for human blood. Hemodynamics were measured by LDA before and after flow diverter implantation. Implantation of a flow diverter device resulted in a reduction of intra-aneurysmal maximum flow velocities of 97.8% at the inflow zone, 89.1% in the dome and 89.3% at the outflow zone, when compared to the native model. A significant reduction of 94% in the mean intra-aneurysmal velocity was found. This promising methodology can optimize patient treatment and will correlate with computational simulations to evaluate their reliability.