CSF

Question 1

Where is CSF produced? and where does it circulate?

Normal CSF pressure

Answer 1

Choroid plexus
Flows out of the ventricles and over surface of brain and spinal cord and subarachnoid space
Absorbed in arachnoid villi

65-195mm per cm CSF fluid

Question 2

Lumbar puncture composition of CSF

Answer 2

Can get CSF fluid as it bathes the spinal cord
-get patient to lie on side and roll up

Compositon

• no red blood cells
• white blood cells, protein, glucose ect.

-can measure CSF pressure as well

Question 3

Function of CSF

Answer 3

homeostasis (constant environment for neurons)
Cushioning for brain
counteracts sudden increase in intracranial pressure

Question 4

What is the blood brain barrier

Answer 4

Membrane separating brain and blood - made of endothelial cells

• very selective about what goes in and out (allows entry of important substances, stops toxins entering)
• provides a stable for neurons to function

Question 5

Intracranial pressure

Answer 5

brain, blood and CSF - Intracranial volume is fixed, so if one increases, than increase in one thing will result in decrease of another, or ICP pressure will increase

Question 6

Causes of Increase ICP

Compensatory mechanisms

Answer 6

Causes

• tumour (increase brain size)
• increase CSF (e.g decreased absorption) , hydrochephalus

CSF is displaced into spinal cord
cerebral viens colapse
increae in CSF absorpiton
lumbosacral dura distendable