CSF and Hydrocephalus

Question 1

how is CSF produced and where

Answer 1

Produced primarily by the choroid plexus (60 to 80 percent) by ependymal cells
found in the lateral ventricle (65%)
third ventricle
fourth ventricle

Question 2

What are the differences between CSF and plasma

Answer 2

CSF is high in Na+, Cl-

low in K+, Ca++, gllucose, and protein

Question 3

what is the Ventricular system and flow

Answer 3

Lateral ventricle to 3rd ventricle via the right and left interventricular foramina of Monro

3rd ventricle to 4th ventricle via cerebral aqueduct of sylvius

4th ventricle to Subarachnoid space via

• 2x Foramina of lushka = Laterally
• 1x Foramina of Magendie = Medially

reabsorbed via the arachnoid granulations and villi

Question 4

What is Hydrocephalus and how does it occur

Answer 4

Increased amounts of intracranial pressure and ventricular dilation due to excessive amounts of CSF accumulations in the ventricles or the subarachnoid space

Congenital or

• overproduction of CSF: communicating (non-obstructive)
• Under-absorption of CSF: ccommunicationg (non-obstructive)
• Obstruction of outflow: non-communicating (obstructive)

Question 5

Aqueductal Stenosis

Answer 5

Non-communicating (obstructive)

accumulation of CSF in the lateral and third ventricles due to obstruction at the cerebral aqueduct

Fluid accumulates in the lateral and third ventricles

causes: Congenital
tumor of pineal gland
memingitis scarring
inflammation from intrauterine infection

Question 6

Normal pressure Hydrocephelus

Answer 6

CSF fails to drain properly leading to enlarged ventricles and cortical atrophy

caused via:
increased CSF viscosity
altered elasticity of ventricular walls
impaired CSF absorption

TRIAD:
Cognitive impairment/confusion (wacky)
Unsteady, magnetic gait (wobbly)
Urinary incontinence (wet)

communicating hydrcephalus (non-obstructive)

Question 7

Dandy Walker Malformation

Answer 7

Congenital brain malformation:
-4th ventricle outlet obstruction leading to cerebellar hypoplasa (partial or complete agenesis of vermis)

Form non-communicating hydrocephalus (obstructive)

fluid accumulates above 4th ventricle

Question 8

Chiari II

Answer 8

Downward displacement of inferior cerebellar vermis and tonsils through the foramen magnum

associated with lumbosacral myelomeningocele

form of non communicating hydrocephalus

fluid accumulates above 4th ventricle

Treatment: shunt to another part of their body, need for rest of life

Question 9

Take homes on hydrocephalus

Answer 9

proximal to obstruction those ventricles will enlarge

if all ventricles are enlarged, think about an absorption issue