Cerebrospinal fluid or otherwise known as CSF is the fluid that is found in the cavity of the brain. It is a clear and colorless liquid produced by the choroid plexus and the ventricles in the brain.

The CSF flows through the space between the arachnoid mater and the pia mater, known as the subarachnoid space. It flows in this space from the brain to the spinal cord.

How is the CSF Circulated?

The CSF is formed primarily from the choroid plexus and some of which from the ventricles and around the blood vessels. Once formed, it flows through the various ventricles as well as in the subarachnoid space. The CSF is prevented from building up in its pathways through vascular reabsorption where it can be secreted through the kidneys in the long run. Aside from being removed from the veins, the CSF is also thought to enter the lymphatic circulation. After which, the choroid plexus continues to form CSF for the body’s use at a rate of 500 ml per day.

The CSF is primarily composed of proteins and electrolytes. However, other byproducts such as urea, excess sugar, bacterial traces as well as blood clots are normally not present and the presence of which indicate an underlying problem in the central nervous system (CNS).

Functions of the Cerebrospinal Fluid

The cerebrospinal fluid is more than just a fluid produced in the central nervous system. It has vital roles including:

  • Applies a buoyant force to the brain

The brain actually weighs 1.4 kg, but with the CSF flowing, it only weighs up to 25 grams. This prevents the brain from putting pressure on itself, which further prevents pressure on the neurons and blood vessels.

  • Provides a cushion for the cerebral cortex

The CSF also serves as a protection for the cerebral cortex from trauma against the skull.

  • Provides immunologic functions

The CSF is also home for circulating white blood cells in cases of infection to the brain and spinal cord. The WBCs in the CSF helps fight the infection in such a way that it reduces more severe bacterial growth in the CNS. During a lumbar puncture, presence of WBC in the CSF may indicate an ongoing CNS infection.

  • Maintains mechanical and chemical protection of the brain and spinal cord

The CSF that circulates in the brain and spinal cord actually reduces the tension that is placed on the delicate tissues of the CNS during mechanical or physical trauma. In terms of chemical protection, the CSF absorbs waste materials in the blood brain barrier and being absorbed back in the blood stream for the waste to be excreted through the kidneys.

  • Auto regulates the cerebral blood flow

The ventricles in the brain have the ability to reduce the production of CSF in cases of increased intracranial pressure. This auto regulation allows the blood vessels in the brain to supply oxygenated blood to the brain tissue since there is no increased pressure inside the skull.

All of these uses make the cerebrospinal fluid an important part of the brain and spinal cord. Nevertheless, utmost care and safety should be employed to protect the CNS from any types of injury.