Cerebrospinal fluid, or CSF, is water-like fluid that fills the ventricles or interior chambers of the brain and surrounds the brain and spinal cord. It is produced by the choroid plexus (a structure lining the floor of the lateral ventricle and the roof of the third and fourth ventricles) as well as through the “weeping" (or transmission) of tissue fluid by the brain into the ventricles.
