CSF Production and Circulation

CSF Production and Circulation

• 95% of CSF is produced by the choroid plexuses in the lateral ventricles and 4th ventricle, with a small amount produced by the ependymal lining of the ventricles.
• CSF production rate: 0.3 ml/min, which is equivalent to 450 ml/24h.
• The total volume of CSF is 150 ml, and it is turned over 3 times every day.

CSF Pathway

• CSF is produced in the lateral, 3rd, and 4th ventricles by the choroid plexus.
• CSF travels from the lateral ventricles through the interventricular foramina of Monro to the 3rd ventricle, then through the cerebral aqueduct of Sylvius to the 4th ventricle.
• CSF leaves the ventricular system at the 4th ventricle through the midline foramen of Magendie and the two lateral foramina of Luschka.
• CSF enters the subarachnoid spaces, circulating to the surface of the brain and spinal cord.

CSF Absorption

• CSF is absorbed primarily by arachnoid villi (granulation) that extend into the dural venous sinuses.
• Arachnoid villi act as unidirectional valves, allowing CSF to leave the subarachnoid space and enter the venous sinuses.