<P> The ventricles are filled with cerebrospinal fluid ( CSF ) which bathes and cushions the brain and spinal cord within their bony confines . CSF is produced by modified ependymal cells of the choroid plexus found in all components of the ventricular system except for the cerebral aqueduct and the posterior and anterior horns of the lateral ventricles . CSF flows from the lateral ventricles via the interventricular foramina into the third ventricle , and then the fourth ventricle via the cerebral aqueduct in the brainstem . From the fourth ventricle it can pass into the central canal of the spinal cord or into the subarachnoid cisterns via three small foramina : the central median aperture and the two lateral apertures . </P>
where does cerebrospinal fluid flow to when it exits the cerebral aqueduct
the fourth ventricle