CSF, Ventricles & Brain Anatomy
Cerebrospinal fluid (CSF)
Cerebrospinal fluid is the clear fluid that surrounds and cushions the brain and spinal cord and circulates through the ventricles.
In short: Cerebrospinal fluid (CSF)
- It cushions and protects the brain and spinal cord.
- About 500 mL is produced each day, with a total volume of roughly 150 mL at any time.
- It is produced, circulated, and absorbed in a continuous balance.
- Hydrocephalus results when this balance is disrupted.
What it is
Cerebrospinal fluid is a clear, water-like fluid that surrounds the brain and spinal cord and fills the ventricles inside the brain. It cushions the brain, supports it, delivers nutrients, and helps remove waste.
Understanding Cerebrospinal fluid (CSF)
CSF is produced continuously — about 500 mL per day — mostly by the choroid plexus within the ventricles, while the total amount present at any one time is only about 150 mL, so the fluid turns over several times daily. It circulates from the ventricles into the spaces around the brain and is absorbed back into the bloodstream, mainly through structures called arachnoid granulations. Hydrocephalus develops when this balance of production, flow, and absorption is disrupted, causing fluid to accumulate. (Figures are general and vary among individuals.)
Why it matters
Understanding CSF is the foundation for understanding hydrocephalus: because the fluid is constantly produced and absorbed in balance, any disruption to flow or absorption can cause it to build up. This is the core mechanism behind the condition.
Common questions
What does CSF do?
It cushions and protects the brain and spinal cord and helps remove waste.
How much is produced?
Roughly 500 mL per day, with about 150 mL present at any time.
How is it related to hydrocephalus?
Hydrocephalus results when the balance of CSF production, flow, and absorption is disrupted.
Bottom line
Cerebrospinal fluid cushions the brain and circulates in a constant balance; hydrocephalus occurs when that balance is disrupted.
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