Coregistration of simulated aneurysms by finite element analysis for evaluation of growth

Understanding the growth patterns of cerebral aneurysms would aid us in determining the essential mechanical factors that may contribute to the initiation, growth, and rupture of these aneurysms and timing of the treatments. Determining the growth patterns of an aneurysm requires registration of a growing geometry; however, co-registration of growing aneurysms is often a great challenge because of deformation in the proximal and distal vasculatures. In this study, we design a simple experiment that allows us to simulate the process of aneurysm growth and to investigate several co-registration algorithms. The experiments involved introduction of a bulge to rubber latex tubing by injection of magnetic resonance contrast agent. Images of the rubber tubing were used to create geometric models for numerical simulations and analyses. Vessels away from the simulated aneurysm were aligned by numerical simulation. We find that vessel alignment gives a better estimation of geometric changes than co-registration of fiducial markers.