Ventricular system is a set of structures containing the cerebrospinal fluid in the brain. It consists of two lateral ventricles, the third ventricle and the fourth ventricle.
Continuity of the ventricular system:
The ventricles of brain are continuous with each other, with the central canal of the spinal cord and with the subarachnoid space, as described below:
- The two lateral ventricles communicate with the third ventricle through the interventricular foramina (foramina of Monro).
- The third ventricle communicates with the fourth ventricle by the cerebral aqueduct (aqueduct of Sylvius).
- The fourth ventricle is continuous below with the central canal of spinal cord.
- The fourth ventricle also communicates with the subarachnoid space through the three foramina in its roof. These foramina are two lateral foramina of Luschka and a medial foramen of Magendie.
Production of the cerebrospinal fluid:
The cerebrospinal fluid is produced in the choroid plexuses of both lateral, third and fourth ventricles of the brain. The producing cells are modified ependymal cells of the choroid plexuses.
Small quantity of the cerebrospinal fluid is also formed around blood vessels and ventricular walls.
Circulation of cerebrospinal fluid:
The circulation of cerebrospinal fluid can be summarized as: