Image 2 shows Schematic of CSF circulation, CSF outflow systems, and the anatomy of various CSF compartments.īlood Supply and Lymphatics However, the arachnoid villi act as 'one way valves'.if the CSF pressure is less than the venous pressure, the arachnoid villi will NOT let blood pass into the ventricular system When the CSF pressure is greater than the venous pressure, CSF will flow into the blood stream. The 5 minute video below is a great summary of the CSF Immune function - The CSF contains immunoglobulins and mononuclear cells. Nutrition - The CSF contains glucose, proteins, lipids, and electrolytes, providing essential CNS nutrition.ĥ.

Biochemical waste products diffuse into the CSF and are removed as CSF is resorbed through arachnoid granulations into venous circulation, a small percentage of CSF also drains into lymphatic circulation.Ĥ.

Biochemical constituents and electrolytes maintain the osmotic pressure responsible for normal CSF pressure which is essential to maintaining normal cerebral perfusion.

Maintains stable intrinsic CNS temperature.

Homeostasis - The biochemical constituents and volume of the CSF play vital cerebral homeostatic roles:.

Otherwise, even minor head bopping will result in severe brain injury.

Shock absorber - It protects the brain from damage during head trauma.

Hence, the entire brain density is cushioned, protecting it from crushing into the bony cranium.

Support - The CSF supports the weight of the brain estimated at 1500 gm and suspends it in neutral buoyancy to a net weight of about 25 gm.

With a lumbar puncture, physicians can look for abnormalities in the CSF, which can be helpful when creating a differential diagnosis

CSF be examined clinically through a lumbar puncture.

Disequilibrium in synthesis and resorption or obstruction of circulation results in CSF accumulation and raised intracranial pressure called hydrocephalus.

Out-pouching of the arachnoid mater (arachnoid granulations) are responsible for the resorption of CSF into the dural venous sinuses.

The composition of CSF is closely regulated, and any variation can be used for diagnostic purposes

Reduction of CSF turnover may contribute to the accumulation of metabolites seen in aging and neurodegenerative diseases.

The constant secretion of CSF contributes to complete CSF renewal four to five times per 24-hour period in the average young adult.

CSF is predominantly secreted by the choroid plexus with other sources playing a more poorly defined role, an adult produces between 400 to 600 ml per day.

Ependymal cells, which create cerebral spinal fluid (CSF), line the ventricles of the brain and central canal of the spinal cord.

Adult CSF volume is estimated to be 150 ml with a distribution of 125 ml within the subarachnoid spaces and 25 ml within the ventricles.

CSF performs vital functions including: Support Shock absorber Homeostasis Nutrition Immune function.

Image 1 shows a 3D image of the CSF circulation as it would look inside the skull.

Spinal fluid in brain