CSF Flashcards
What is the normal volume of CSF per day?
500mls
What is CSF produced by?
Ependymal cells in the choroid plexus
What is the CSF absorbed by?
Arachnoid granulations in the dural venous sinus
Where is the lumbar cistern?
Between L2 and S2
What is the normal value for ICP?
10mmHg
What level is a lumbar puncture performed?
L3/4
What are all the functions of the CSF?
Neutral buoyancy
Provides a buffer, absorbing and dissipating the energy
Clearing waste, accommodating to changes in intracranial volume
Provide micronutrients to cerebral tissue e.g. Vit C, Thyroxine
What is the amount of RBCs normally present in the CSF?
NO RBCs
The rate of CSF production is dependent on the cerebral perfusion and ICP TRUE/FALSE
FALSE
CSF production continues independently of cerebral perfusion and ICP
TRUE/FALSE CSF Production decreases in the elderly
TRUE
How does the CSF move from the lateral ventricles to the third ventricle?
Foramina of Munro
How does the CSF move from the third ventricle to the fourth ventricle?
Through central aqueduct of Sylvia
How does the CSF move from the fourth ventricle to the SAS?
Foramina of Luschka and Magendie
Name 6 CSF pathologies
Hydrocephalus Spontaneous intracranial hypertension Syringomyelia Intracranial arachnoid cysts Dandy walker cysts Spinal arachnoid webs
What are 4 CNS pathologies?
Cerebral oedema
Benign intracranial hypertension
Spinal dural arteriovenous fistulae
Syringomyelia (& Cord Oedema)
What are the 3 reasons that there would be increased CSF?
Overproduction at source
Inhibition of reabsorption
Obstruction to the flow of CSF
What would be evident from CSF for narcolepsy?
Low or undetectable levels of CSF orexin/hypocretin
What would be the CSF findings if someone has idiopathic intracranial hypertension?
High opening pressure
What is Xanthochromia present in?
Present in the CSF if the patient has Creutzfelt-Jakob syndrome
Oligoclonal bands found in the CSF indicate which disease?
Multiple Sclerosis
Which condition on CSF has an increase in phosphorylated tau protein and decrease in B-amyloid?
Alzheimer’s
What is hydrocephalus?
Accumulation of excessive CSF within the ventricular system of the brain
What is a common cause of non-communicating hydrocephalus?
Aqueduct stensosi
What causes communicating hydrocephalus?
When arachnoid granule absorption defects
What age does the suture typically close?
2-3 years
If hydrocephalus occurs before closure of the cranial suture then what occurs?
Cranial enlargement
If hydrocephalus occurs after the closure of the cranial suture then what occurs?
Expansion of ventricles and increase in ICP
What causes cerebral atrophy?
Dementia
Who is central aqueduct stenosis most common in?
Children
What do these signs point to as a clinical condition?
- Unusually large head
- Thin and shiny scalp with easily visible veins
- Bulging or tense fontanelles
- Downward looking eyes “sunsetting”
- Failure to thrive
- If congenital picked up during an US
Hydrocephalus
What is the treatment for hydrocephalus?
Ventricular Peritoneal Shunt
How is the risk of infection reduced when inserting a ventricular peritoneal shunt?
Antibiotic or silver impregnated shunts
Use iodine +++
What are the 4 steps in the development of normal pressure hydrocephalus?
1-Drainage of CSF blocked
2-Collagen disorders
3-Dural Diverticula
4-Trauma
Aside from idiopathic what is the other cause of normal pressure hydrocephalus?
Post-inflammatory
e.g. SAH,Meningitis, Trauma and craniotomy
What is the triad that normal pressure hydrocephalus presents with?
Ataxia
Memory decline/reversible dementia
Incontinence
What are the 4 causes of spontaneous intracranial hypotension?
1-Idiopathic
2-Collagen disorder
3-Dural diverticula
4-Trauma
What is Syringomyelia?
Cystic enlargement of the spinal cord
What is the mean age of presentation fo Syringomyelia?
30
What is the commonest cause of syringomyelia?
Arnold-Chiiari II malformation
Expansion of spinal canal interferes with the fibres of the anterior white commissure of spinothalamic tract. Therefore what is affected?
Pain, Temperature , Crude Touch
Why is hyperhydrosis a feature of early stage syringomyelia?
Hyperactivity in pre-ganglionic neurones
What is the treatment of syringomyelia if it is caused by chair malformation?
Posterior fossa decompression
What is the degree of difficult in operating on syringomyelia proportional to?
The extent of intramural fibrosis
Collapse of the syrinx cavity
Name two conditions where there is Hydrocephalus ex vacuo?
Alzheimer’s disease
Picks disease
