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

Biorheology. 2014;51(6):341-54. doi: 10.3233/BIR-14019.

Abstract

Background: 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.

Objective: 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.

Methods: 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.

Results: 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.

Conclusions: This promising methodology can optimize patient treatment and will correlate with computational simulations to evaluate their reliability.

Keywords: Stent; endovascular; flow diversion; laser Doppler anemometry; non-Newtonian fluid.

MeSH terms

  • Blood Flow Velocity
  • Cerebral Angiography
  • Humans
  • Intracranial Aneurysm / diagnostic imaging
  • Intracranial Aneurysm / physiopathology*
  • Models, Cardiovascular*
  • Stents*
  • Tomography, X-Ray Computed