Wednesday 6 October 2010

MRCP revision battle 25.4: Normal pressure hydrocephalus

Normal pressure hydrocephalus is a triad of:
  1. dementia
  2. gait abnormality
  3. urinary incontinence
(remember as DUG!)


It is caused by a defect in the absorption of CSF.
Causes include: meningitis, head injury, subarachnoid haemorrhage.


Note that there is NO headache and NO papilloedema.


Investigations:
  • CT head (predictably) - enlarged ventricles
  • large volume lumbar puncture - ? high opening pressure, ? improvement of symptoms
  • lumbar infusion test

Treatment is a shunt.



Next up... gas gangrene!