Three-dimensional Flow Profile in the Ventral Third Ventricle of the Brain

A complex transport network driven by coordinated motile cilia inside the ventral third ventricle (v3V) of mammalian brain was recently reported. This network generates cerebrospinal fluid (CSF) flow patterns such as a separatrix and a whirl that establish intraventricular boundaries. The CSF flow in the overall three-dimensional v3V cavity was studied numerically via the Lattice Boltzmann Method and Immersed Boundary Method. In particular, the experimental trajectory data obtained by tracking fluorescent beads were converted to velocity vectors and processed by the Smoothed Particle Hydrodynamics. The velocity maps were refined by considering divergence-free and projected onto a curved virtual surface representing cilia tips, with a constant gap from the v3V wall. Three-dimensional flow features with likely physiological consequences were uncovered numerically.