CSF Flow Characterization within a Model of the Cerebral

ABSTRACT: Hydrocephalus is a disorder that is characterized by enlargement or dilation of the cerebral ventricular system. Several theories have been proposed regarding the causation of hydrocephalus; however, more recent theories stress a hydrodynamic origin to chronic hydrocephalus. In order to characterize the flow of Cerebral Spinal Fluid (CSF) within the third ventricle and aqueduct of a healthy adult, a ventricular model is developed using Rapid Prototyping (RP) technology and a PDMS material. The model is placed in a steady flow loop and Particle Image Velocimetry (PIV) is used to obtain 2D velocity vector maps of the flow in the mid-sagittal plane for the cranio-caudal as well as caudo-cranial flow directions of CSF analog fluid. CINE flow MR data from the literature have been used to ensure that CSF analog steady flow rates in the loop correspond to flow rates within the physiological range. Very low bi-directional flow rates are obtained using PIV in a model employing a CSF analog fluid contained in a realistic geometry of the ventricular anatomy, which has never been reported in the literature. The PIV results demonstrate that the highest velocities occur in the mid-aqueduct region of the test section and the lowest velocities occur in a dead zone located in the antero-inferior region of the third ventricle, which agrees with previous studies. In the case of cranio-caudal flow, the PIV results showed a relatively small recirculation region located adjacen