Flow Energy and Vessel Biology of the Cerebral Aneurysm

Objective:

The goal of the proposed project is to continue developing and validating a numerical model that simulates the principal mechanisms involved in the formation and the endovascular treatment of aneurysms. Validation requires use of adequate methodologies to compare and match virtual with real world observations. Ex-vivo and in-vitro models, and where unavoidable, succinct use of animal models are needed to obtain highly valued biological validation information.

Energy of cerebral blood flow may lead in approx. 2-4% of people to vessel wall fatigue with creation of an intracranial aneurysm that may carry a risk of rupture. Vessel and blood biology are both critically influenced by shear, a measure of friction between moving elements of blood and the endothelial lining of the vessel wall. Clot formation is also closely involved in endovascular treatment with good and bad effects. Computational study of wall remodeling effects could include areas and quality of clot formation, that are understood to critically drive the biology of the vessel wall by inflammation and degradation mechanisms.As in any other field of biomechanical engineering, numerical simulations offer the possibilities to test a variety of scenarios and mechanisms allowing for forecasting disease evolution and for treatment planning. Since current medical imaging can provide exact 3D replicas of concerned patients, we wish to understand critical mechanisms that would help to predict rupture risk in unruptured aneurysms and in case of treatment need, to choose the optimal implant with the best chance to produce healing, i.e. reverse remodeling of the vessel wall. Once the interplay of clot formation and suitable endovascular implants is better understood, predictive techniques will support patientspecific, personalized assessment to increase the saftey of the intervention.

Participants: Dr. Julien Egger, Prof. Dr. Sven Hirsch, Prof. Gábor Székely

Partners:

Neuroradiology, Hirslanden Clinic (Prof. Rüfenacht)
CABMM, University of Zurich
IT’IS foundation
Gyrotools

Aaron Fogelson, University Utah