Condition- Hydrocephalus

Question 1

What is a hydrocephalus?

Answer 1

Accumulation of CSF within the ventricular system of the brain

caused by an imbalance between CSF production and absorption or blockage to flow

Question 2

How can Hydrocephalus be classified?

Answer 2

Obstructive (non-communicating)

vs

Non-obstructive (communicating)

Question 3

What is obstructive hydrocephalus

Answer 3

Caused by structural pathology blocking flow of CSF

Question 4

List some causes of obstructive hydrocephalus

Answer 4

• Tumours (in the 3rd/4th/ aqueduct)
• Posterior fossa tumour compressing on the 4th ventricle
• Developmental abnormalities (e.g. aqueduct stenosis)
• Acute haemorrhage:
  
  • subarachnoid haemorrhage
  • intraventricular haemorrhage (lesions in 3rd/ 4th ventricle/cerebral aqueduct)

Question 5

What is non-obstructive hydrocephalus

Answer 5

Caused by increased CSF production or impaired re-absorption of CSF

Question 6

List some causes of non-obstructive hydrocephalus

Answer 6

• Increased production of CSF: choroid plexus tumour (very rare)
• Failure of reabsorption at the arachnoid granulations: meningitis, post-haemorrhagic
• Normal pressure hydrocephalus
• Idiopathic

Question 7

What is a normal pressure hydrocephalus

Answer 7

Idiopathic enlargement of the ventricles but with normal ventricular pressure

Question 8

Describe the epidemiological distribution of patients with hydrocephalus

Answer 8

BIMODAL DISTRIBUTION

YOUNG - congenital malformations and brain tumours

ELDERLY - strokes and tumours

Question 9

List some of the presenting symptoms of an acute Hydrocephalus

Answer 9

• Nausea and vomitting
• Headaches
• Papilloedema

Question 10

List some of the presenting symptoms of a Normal Pressure Hydrocephalus

Answer 10

Forms a Triad:

1. Dementia
2. Gait disturbance
3. Urinary incontinence
4. (may get hyperreflexia)

Question 11

List some of the symtpoms of a gradual onset hydrocephalus

Answer 11

• cognitive impairment
• gait apraxia
• diploplia
• CN palsies

Question 12

List some of the signs of Hydrocephalus in adults on physical examination

Answer 12

• Reduced GCS
• Papilloedema
• 6th nerve palsy

Question 13

Why might you get 6th nerve palsy inn hydrocephalus?

Answer 13

6th nerve has the longest intracranial path of all the cranial nerves and so is most susceptible to palsy due to raised ICP

Question 14

List some signs of Hydrocephalus in neonates on physical examination

Answer 14

Increased head circumference- swelling at anterior fontanelle in particular

Sunset eyes (downwards cast)

Question 15

Compression of which structure in the brain leads to the development of ‘sunset’ eyes in neonates with hydrocephalus?

Answer 15

Compression of superior colliculus in the midbrain

Question 16

What is the first line investigation for someone with presenting with signs and symptoms of Hydrocephalus

Answer 16

CT Head

• FIRST-LINE for detecting hydrocephalus- will see vernticular enlargement. May also see cerebral infarction
• May also pick up the cause (e.g. tumour)

Question 17

Which investigations might you conduct on someone with Hydrocephalus?

Answer 17

• CT/MRI Head
• CSF analysis (either from ventricular drain or LP)

Question 18

Why might you adminster levodopa to investigate a patient presenting with a shuffling gait and suspected hydrocephalus

Answer 18

To distinguish between a shuffling gait caused by hydrocephalus and one caused by Parkinsons