Cerebrospinal fluid (CSF)

Fluid that helps cushion, support the weight, and maintain the shape of the brain and spinal cord. It also helps to clear waste, circulating throughout the brain, and regulate intracranial pressure by adjusting its volume. Produced by the choroid plexus located within the lateral, third, and fourth ventricles and ependymal cells, this fluid can be found within the meninges as well as the ventricles in the brain. At any point in time, there is an average of 125 to 150 mL of cerebrospinal fluid (CSF) in the body, constantly being produced, circulated, and reabsorbed into the blood by the arachnoid villi. Lumbar puncture procedures allow CSF to be sampled and examined.