Cerebrospinal Fluid

Question 1

CSF volume?

Answer 1

150mls in adults (500mls a day)

10-60mls in neonate

Question 2

Function of the CSF?

Answer 2

Cushions the brain against mechanical forces
Contributes to maintaining intracranial pressure at a constant level
Transports metabolic waste products, antibodies, chemicals, and pathological products of disease away from the brain and spinal-cord tissue into the bloodstream

Question 3

The CSF flows through which foramen to reach the subarachnoid space?

Answer 3

Magendi and Luschka

-Absrobed through the arachnoid villi into the venous drainiage system of the brain

Question 4

What does raised protein in the CSF suggest?

Answer 4

Inflammation or infection

Question 5

What should glucose level be in CSF?

Answer 5

Should be at least 2/3rds that of blood glucose

A ratio of BG less than 0.5 is pathological

Question 6

Oligoclonal protein bands

Answer 6

Indicate inflammation in the CNS

Question 7

How many RBC should be in the CNS?

Answer 7

0

Question 8

How many WBC should you have in CSF?

Answer 8

<5WBC/ml

Question 9

How much protein should be in CSF?

Answer 9

Less than 2g/dl

Question 10

What level are the iliac crests?

Answer 10

L4

Question 11

Which structures does the spinal needle pass through?

SSS I L EDS

Answer 11

Skin
Superficial connective tissue
Supraspinous ligament
Interspinous ligament
Ligamentum flavum
Epidural spec
Dura mater (dural sac)
Subarachnoid space (lumbar cistern)

Question 12

Indications for lumbar puncture

Answer 12

1) Suspected CNS infection
2) Suspected subarachnoid haemorrhage
3) Therapeutic reduction of CSF pressure
4) Sampling of CSF for any other reason

Question 13

Contraindications to lumbar puncture

Answer 13

1) Local skin infections over proposed puncture site
2. Raised intracranial pressure (ICP)
3. Suspected spinal cord mass or intracranial mass lesion (based on lateralizing neurological findings or papilledema)
4. Uncontrolled bleeding diathesis
5. Spinal column deformities (may require fluoroscopic assistance)
6. Lack of patient cooperation (anaesthetic may be required in children)

Question 14

CPP

Answer 14

Cerebral perfusion pressure

(the brain is metabolicaaly very active and requires a constant delivery of oxygen and glucose/energy to function normally)

Question 15

How do you calculate CPP?

Answer 15

Mean arterial blood pressure - intracranial pressure

Question 16

What will decrease CPP?

Answer 16

Decreased MABP

Raised intracranial pressure

Question 17

Setting sun sign

Answer 17

Hydrocephalus

Question 18

Prominent scalp signs may be a sign of what?

Answer 18

Hydrocephalus

Question 19

Most important sign of hydrocephalus?

Answer 19

Enlarging head circumference

Question 20

If you have hydrocephalus, what time of day would you get headaches?

Answer 20

Morning

-vomiting is more significant in the morning as well

Question 21

Why might you get neck pain in hydrocephalus?

Answer 21

Tonsillar invasion

Question 22

Which nerve is responsible for double vision?

Answer 22

Sixth nerve palsy

Question 23

Signs and symptoms of hydrocephalus in the adult and older child?

Answer 23

Slowing of mental capacity, cognitive deterioration
Headaches (initially in the morning)
Neck pain, suggesting tonsillar herniation
Vomiting, more significant in the morning
Blurred vision: A consequence of papilledema and, later, of optic atrophy
Double vision: Related to unilateral or bilateral sixth nerve palsy
Difficulty in walking secondary to spasticity: Preferentially affects the lower limbs because the periventricular pyramidal tract is stretched by the hydrocephalus
Drowsiness

Question 24

Investigations for hydrocephalus?

Answer 24

US, CT, MRI

Question 25

Aqueductal stenosis

Answer 25

Narrowing of the aqueduct of Sylvius which blocks the flow of CSF in the ventricular system

Most common cause of congenital obstructive hydrocephalus

Question 26

Arnold Chiari malformation

Answer 26

This is usually only seen in children born with spina bifida

In arnold chiari malformation, both the cerebellum and the brain stem extend into the foramen magnum

Question 27

How do you treat hydrocephalus?

Answer 27

Ventriculoperitoneal shunt