entricular system The ventricular system has been covered before and so we know there are 4 ventricles, or hollow spaces containing CSF, the liquid that nourishes and feeds the brain cells as well as remove wastes.
The fluid is filtered from blood by the choroid plexi and released to the ventricular system. The lateral ventricles are the first and then the csf moves to the third ventricle, then the cerebral canal and then the fourth ventricle.
From there it flows out of the 2 lateral apertures and median apertures. Then it flows around the brain and spinal cord to the sinuses and are drained.
After flowing out of the apertures it works its way around the outside of the brain, and there are subarachnoid cisterns, which are like spaces that contain relatively more csf, analogous to ventricles but smaller. The names of these are the: Cisterna magna, pontine cistern, interpeduncular cistern, and superior cistern.
choroid plexi
the inferior medullary velum has it but the superior does not.