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Accueil > Groupes de Recherche > Particules, Sprays et Combustion > Transferts, écoulements et suspensions biologiques > Flow and transport in cerebro-spinal spaces

Flow and transport in cerebro-spinal spaces

28 mai 2013

Academic involved : Gérald Bardan, David Lo Jacono (GR EMT2) Franck Plouraboué, M. Zagzoule (GR Interface) Collaborator : Olivier Balédent CHU Amiens

Cerebro-spinal fluid oscillates due to the change in volume of pulsatile cerebral arteries.

First, we analyse such flows in order to reconstruct the transmantle pressure (pressure difference between the brain surface and the ventricles). From measurements of the oscillating flux of the cerebrospinal fluid (CSF) in the aqueduct of Sylvius, we elaborate a patient-based methodology for transmantle pressure and shear evaluation.

High-resolution anatomical magnetic resonance imaging first permits a precise 3-D anatomical digitalized reconstruction of the Sylvius’s aqueduct shape. From this, a very fast approximate numerical flow computation, nevertheless consistent with analytical predictions, is developed. Our approach includes the main contributions of inertial effects coming from the pulsatile flow and curvature effects associated with the aqueduct bending. Integrating the pressure along the aqueduct longitudinal center- line enables the total dynamic hydraulic admittances of the aqueduct to be evaluated, which is the pre-eminent contribution to the CSF pressure difference between the lateral ventricles and the subarachnoidal spaces also called transmantle pressure. The application of the method to 20 healthy human patients validates the hypothesis of the proposed approach and provides a first database for normal aqueduct CSF flow. Finally, the implications of our results for modeling and evaluating intracranial cerebral pressure are discussed.

We also analyze transport issues associated with confined weakly inertial pulsatile flows. From using a long-wavelenth asymptotic analysis we analyze the steady-streaming flow confined between
two wavy surfaces at arbitrary Womersley number (neither very small or very large). Various transport regimes are currently under study.

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