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Flashcards in CSF And Hydrocephalus Deck (36)
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1
Q

What are the 2 types of hydrocephalus and what causes the CSF to build up?

A

Communicating hydrocephalus - problem with resorption of CSF

Non-communicating hydrocephalus - obstruction of the normal flow of CSF

2
Q

What’s the aetiology of communicating hydrocephalus?

A

Infection (after meningitis)
Subarachnoid haemorrhage
Post operative
Head trauma

3
Q

How can subarachnoid haemorrhage cause hydrocephalus? And what type of hydrocephalus is this?

A

Can cause communicating hydrocephalus

The blood causes scarring of the arachnoid villi therefore aren’t able to resorb the CSF as efficiently

4
Q

What are the signs and symptoms of communicating hydrocephalus in a child/infant?

A

Failure to thrive
Paranoids sign - eyes will look down the way, sun setting eyes
Disproportional increase in head circumference (due to cranial sutures not be fused yet)

5
Q

What are the signs and symptoms of communicating hydrocephalus in an adult / adolescence?

A

Symptoms of raised ICP;

  • headache - worse in the morning, when leaning forward, when lying down
  • nausea and vomiting
  • pappiloedema
  • abducens nerve palsy
  • gait disturbance
6
Q

What nerve palsy can you get with raised ICP and why?

A

Abducens (CN VI) palsy because it has the longest course through CSF so it most likely to get damaged

7
Q

Communicating hydroceaphlus can also be caused by an increase in production of CSF, in which condition can this occur in?

A

Choroid plexus papilloma can present this way but it is very rare

8
Q

What is the aetiology of non-communicating hydrocephalus?

A
Aqueductal stenosis
Tumours/cancer/masses
Cysts
Infection
Haemorrhage/haematoma 
Congenital malformations/conditions
9
Q

Give an example of a cyst that could cause non communicating hydrocephalus.

A

Cholloid cysts in the 3rd ventricle

10
Q

In a CT or MRI what is the first sign of hydrocephalus?

A

Dilatation of lateral ventricle horns

3rd ventricle will become ballooned

11
Q

Because everyone has different sizes of ventricles, how would you distinguish between normal and pathologically large ventricles?

A

Evans ration >30% in hydrocephalus

Ventricular index >50% in hydrocephalus

12
Q

What is the treatment for communicating hydrocephalus?

A

External ventricular drain EVD

Shunt

13
Q

What is the treatment for non-communicating hydrocephalus?

A

Treat by removing the source of the obstruction

Ventriculostomy with VP shunt is also an option

14
Q

What is the disadvantage of pacing a shunt in?

A

They have a high failure rate of 40% within first year, 50% within 5 years and it goes up 5% each year

15
Q

What causes the failure of the ventricular shunts?

A
Mechanical failure from occlusion/disconnection
Migration
Over or under drainage
Infection
Skin erosion
16
Q

What is normal pressure hydrocephalus?

A

Commonly a preventable and/or curable cause of dementia

17
Q

What are the symptoms/signs of normal pressure hydrocephalus?

A

Wet, wobbly, wacky
Urinary incontinence
Gait disturbance
Rapidly progression dementia

18
Q

What is the typical gait of someone with normal pressure hydrocephalus?

A

Short steps
Shuffling feet
Wide stance

19
Q

What investigations would you carry out for investigating suspected normal pressure hydrocephalus?

A
Lumbar puncture (normal opening pressure)
CT / MRI
20
Q

what is the treatment for normal pressure HYDROCEPHALUS?

A

Programmable VP shunt

Programmable because they are often sensitive to pressure changes

21
Q

What symptoms improve in normal pressure hydrocephalus?

A

Most likely to improve is gait > incontinence > dementia

22
Q

CSF exits the 4 th ventricle through what?

A
Foramen lushaka (2 lateral foramina)
Foramen magendie (1 medial formina)
23
Q

What is the resorption of CSF by arachnoid villi driven by?

A

Resorption is driven by the pressure gradient between the intracranial space and the venous system

24
Q

The production of CSF independent on what ion being pumped into where?
Is this an active or passive process?

A

CSF production is dependant on Na being actively pumped into the subarachnoid space so water follows (CSF)

25
Q

What conditions would you require a lumbar puncture for diagnosis and/or treatment?

A
Meningitis
Meningoencephalitis
Subarachnoid haemorrhage 
Malignancy
Idiopathic inter cranial hypertension
Infusion of drugs or contrast
26
Q

What are the contraindications for performing a LP?

A

Unstable patient with CVS or respiratory instability
Localised skin/tissue infection
Evidence of unstable bleeding disorder i.e. on warfarin, clotting deficiency, platelets <50,000
Increased ICP
Chiari malformations (low lying cerebellar tonsils)

27
Q

Why is a manometer attached when you attain the CSF in a lumbar puncture?

A

To obtain the opening pressure

28
Q

How is the CSF obtained from an LP interpreted to aid with diagnosis?

A

Tube 1 - culture and gram stain
Tube 2 - glucose & protein
Tube 3 - cell count and differentiation

29
Q

What are the complications from a lumbar puncture?

A
Spinal headache
Apnea 
Back pain 
Bleeding or fluid lead around spinal cord
Subarachnoid epidermis cyst
Nerve trauma 
Brainstem herniation 
Infection, pain, haematoma
30
Q

What are the risk factors for a spinal headache post LP?

A

Female
18-30 years
Lower BMI
History of spinal headache

31
Q

What si the treatment for a spinal headache post LP?

A

Supine position for 2 hours
Hydrate
Caffeine
Epidural blood patch

32
Q

How do you prevent a spinal headache from an LP?

A

Pass the needle bevel parallel to the longitudinal nerve fibres of the dura
Replace stylet before removing the needle
Use smaller diameter needle
Use traumatic needle

33
Q

How does an epidermal inclusion cyst occur as a complication from an LP?

A

When a core of skin is driven into spinal or paraspinal space with hollow needle

34
Q

What are the symptoms of nerve root trauma from an LP?

A

Dysaethesias, electric shocks

Back pain

35
Q

If herniation occurred as a complication from an LP, how would you treat?

A

Supine position to improve venous return from the brain

Intubate or ventilate

36
Q

What is the normal opening pressure range for LP?

A

6-16mm/H20