While the central nervous system is in the process of development, it shows enlargements in some parts of the brain. Each of these enlargements, called ventricles, contains cerebrospinal fluid (CSF). CSF fills the central nervous system. Therefore, it prevents the structures it surrounds from being damaged by shocks occurring in the body. Apart from this, it also plays an important role in the substance exchange of nerve cells. Problems in the production or absorption of CSF or impaired circulation may lead to the emergence of different pathological conditions.