Hydrocephalus

Question 1

what is the pathway of CSF?

Answer 1

ventricles –> subarachnoid space –> resorbed back into venous system via arachnoid granulations

Question 2

pathology?

Answer 2

excess CSF in interventricular space

Question 3

classification?

Answer 3

• Communicating
  
  • Non-obstructive
• Non-communicating
  
  • obstructive
• Normal Pressure

Question 4

describe the abnormality in communicating hydrocephalus

Answer 4

failure of CSF resorption from subarachnoid space

Question 5

aetiology of communicating hydrocephalus

Answer 5

• SAH
• infection
• congenital abnormality in arachnoid villi

Question 6

describe the abnormality in non-communicating hydrocephalus, and the aetiology

Answer 6

obstruction of CSF flow from brain to subarachnoid space

• tumour
• cyst, abscess
• infection
• haemorrhage
• congenital malformation eg spina bifida

Question 7

Rx?

Answer 7

• Ventriculo Peritoneal shunt
• removal of obstructing lesion

Question 8

how does normal pressure hydrocephalus present?

Answer 8

wet, wobbly, whacky

• wet- urinary incontinence
• wobbly- gait disturbance
• whacky- quicky, progressive dementia

on CT/MRI–> communicating hydrocephalus

Question 9

contraindications to LP?

Answer 9

• Unstable patient with cardiovascular or respiratory instability
• Localized skin/soft tissue infection over puncture site
• Evidence of unstable bleeding disorder (platelets <50,000 / clotting factor deficiency)
• Increased ICP
  
  • Head CT before, if focal neurological findings – to rule out impending cerebral mass herniation