Finding the Most Optimal Material Properties and Analysis Method for Biomechanical Numerical Simulation of Head in Hydrocephalus Patients

In the present study, the head Cine PC-MRI was done in a normal subject and 11 patients with hydrocephalus. Then the head point cloud was produced and the head 3D model of all subjects was built. All models were fluid-structure interaction (FSI) analyzed under two assumptions of linear elastic (assumption A) and linear viscoelastic (assumption B) of brain tissue. Following the validation of the CSF velocity data obtained experimentally and from numerical simulation, other results were extracted. Results showed that the error between CSF velocity, Reynolds number and stroke volume data obtained under assumptions A and B of patients are less than 4.2%, 4.4% and 0.3%, respectively. Hence, the assumption of linear elastic for brain tissue is a more optimal choice to analyze these parameters in head as it reduces the calculation time greatly. However, the error between CSF pressure data obtained under assumptions A and B is greater than 17% and therefore, it is necessary to use the assumption of linear viscoelastic for brain tissue for analysis of CSF pressure. By the way, the computational fluid dynamics (CFD) solution is an appropriate technique for analysis of diseases with a cause outside the ventricular system but it is necessary to use FSI solution for investigating diseases whose cause is inside the ventricular system as the displacement of fluid-solid interface is considerable

Keywords:

Cerebrospinal fluid , Computational fluid dynamics , Fluid-structure interaction , Elastic , Viscoelastic , Brain , Magnetic resonance imaging