Using Computational Solid Dynamics to Assess the Contact Effect of a Stent Expansion on an Aneurismatic Cerebral Artery

• Grant number: 24/08176-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2024
• End date: December 15, 2025
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Iago Lessa de Oliveira
• Grantee: Lucas Marcel Aparecido Costa Pilati
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Associated research grant: 23/06609-9 - Numerical Simulation of Intracranial Aneurysms Flow: An Investigation on Wall Curvature and Microsurgical Clips Effects in their Hemodynamics and Wall Mechanics, AP.R
• Associated scholarship(s): 24/21031-6 - Numerical Simulation of the Contact of a Stent on an Aneurismatic Cerebral Artery with solids4foam, BE.EP.IC

Abstract

Intracranial aneurysms (IAs) are abnormalities formed in the cerebral arteries characterized by outpouching regions of their walls. The danger with these lesions occurs if they rupture, which causes an intracranial haemorrhage and possibly leads to the death of the patient, presenting a mortality rate as high as 50 %. The rupture event is hard to predict, though, and surgical treatments also pose risks to patients. Hence, due to a better outcome for the patient and low risk of postsurgical complications, the procedure known as embolization has become the most common option among neurosurgeons. In this procedure, the IA is filled with coils, to stop blood flowing into the aneurysm and, subsequently, a stent is placed inside the artery to prevent the migration of coils. However, the exact interaction between the stent and coils with the blood flow and, mainly, with the arterial wall was poorly investigated. In this context, the Computational Solid Dynamics (CSD) technique was also used to understand the stent deployment inside the artery. However, due to the complex geometry of a stent and the lack of information regarding the models that should be used to represent aneurysm tissue, few numerical studies have looked into the effect that stents cause on the aneurysm wall and artery upon release when the former are modelled as hyperelastic solids, the typical model that should be used for these arteries. In this context, the main goal of this research project is to evaluate this interaction in a model of an artery with an aneurysm. By using OpenFOAM® and its extension solids4foam, which implements the Finite Volume Method to simulate the motion of solids, the release of a stent and its subsequent interaction with a model of the internal carotid artery with a lateral aneurysm will be simulated. Local variables, such as the stress and strain fields, and global ones, such as the force and displacement of the stent and arterial wall, will be analyzed. The results of this work may lead to a better understanding of the effects of stents and, in due course, to a better stent design.