Engineering Applications of Computational Fluid Mechanics (Dec 2022)
Computational modeling and simulation of stenosis of the cerebral aqueduct due to brain tumor
Abstract
Stenosis of the cerebral aqueduct (CA) is featured in many studies relating to elevated intracranial cerebral pressures. It also presents a challenging situation to clinicians. Compressive forces play a lead role in pathological situations such as the presence of tumors and hence can cause obstruction to the flow of cerebrospinal fluid (CSF). Because of this barrier, excessive retention of CSF in the ventricles can occur. This, in turn, can contribute to increased pressure gradients inside the cranium. Most of the numerical models in the literature are restricted to modeling the CSF flow by considering the ventricle walls as rigid material, although in reality they are deformable. This paper, therefore, addresses the same from a holistic perspective by taking into consideration the dynamics of the flexible characteristics of the ventricular wall. It adds novelty to this field by reconstructing anatomically realistic ventricular wall behavior. To do this, the authors aim to develop a computational model of stenosis of the CA due to a brain tumor by invoking a fluid–structure interaction (FSI) method. The proposed three-dimensional FSI model is simulated under two cases: first, simulation of the pre-stenosis case with no interaction of tumor forces and, secondly, a stenosis condition with dynamic interaction of tumor forces. Comparison of the forces with and without a tumor reveals a marked obstruction of CSF outflow after the third ventricle and CA. In addition, a drastic rise in CSF velocity from 21.2 mm/s in the pre-stenosis case to 54.1 mm/s in the stenosis case is observed, along with a net increase in deformation of 0.144 mm on the walls of the ventricle. This paper makes a significant contribution to brain simulation studies for pressure calculations, in which the presence of tumors is a major concern.
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