ABSTRACT
THE VENTRICULAR SYSTEM The ventricular system (Fig. 25.1) comprises two lateral ventricles, the third ventricle, the cerebral aqueduct (of Sylvius), the fourth ventricle and the spinal canal. The ventricular system is filled with cerebrospinal fluid (CSF), which is produced by epithelium of the choroid plexus; this choroid plexus is present in the lateral, third and fourth ventricles. The epithelium has a rich blood supply and invaginates into the ventricular cavities. The CSF flows through the ventricular system and exits into the subarachnoid space via the two lateral foramina of Luschka and the medial foramen of Magendie, located in the fourth ventricle. The CSF passes from the subarachnoid spaces into the dural venous sinuses via the arachnoid granulations.
