Further evidence for the dynamic stability of intracranial saccular aneurysms

J Biomech. 2003 Aug;36(8):1143-50. doi: 10.1016/s0021-9290(03)00083-6.

Abstract

It has long been thought that intracranial saccular aneurysms enlarge and rupture because of mechanical instabilities. Recent nonlinear analyses suggest, however, that at least certain sub-classes of aneurysms do not exhibit quasi-static limit point instabilities or dynamic instabilities in response to periodic loading, and consequently, that the natural history of these lesions is likely governed by growth and remodeling processes. In this paper, we present additional results that support the finding that one particular sub-class of saccular aneurysms is dynamically stable. Specifically, we extended recent results of Shah and Humphrey, which are based on the assumption that some saccular aneurysms can be modeled as spherical elastic membranes surrounded by a viscous cerebrospinal fluid, to account for a viscohyperelastic behavior of the aneurysm. It is shown that inclusion of a "short-term" viscoelastic contribution to the mechanical behavior of an aneurysm serves to increase its dynamic stability against various disturbances.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Aneurysm, Ruptured / etiology*
  • Aneurysm, Ruptured / physiopathology*
  • Blood Pressure
  • Computer Simulation
  • Elasticity
  • Hemorheology / methods*
  • Homeostasis
  • Humans
  • Intracranial Aneurysm / classification
  • Intracranial Aneurysm / complications*
  • Intracranial Aneurysm / physiopathology*
  • Models, Cardiovascular*
  • Nonlinear Dynamics
  • Pulsatile Flow
  • Viscosity