Normal Pressure Hydrocephalus

Question 1

Is Normal Pressure Hydrocephalus reversible or irreversible?

Answer 1

reversible

Question 2

What causes it?

Answer 2

Reduced absorption at the arachnoid villi

Due to head injury, subarachnoid haemorrhage or meningitis.

Question 3

What is the classic triad of normal pressure hydrocephalus?

Answer 3

• Urinary incontinence
• Dementia and bradyphrenia (slowness in mental processes)
• Gait abnormality (may be similar to Parkinson’s disease)

Question 4

On CT imaging, what would be seen?

Answer 4

An enlarged 4th ventricle

Question 5

How is normal pressure hydrocephalus managed?

Answer 5

Ventriculoperitoneal shunt

Question 6

A 76-year-old man is reviewed in the Elderly Medicine clinic. He is concerned about his increasing forgetfulness over the past six months. His daughter notes he has generally ‘slowed down’ and struggles to follow conversations. Over the past month he has noted increasingly frequent episodes of urinary incontinence. He has also had one episode of faecal incontinence in the past week. On examination he is noted to have brisk reflexes and a short, shuffling gait. No cerebellar signs are noted. What is the most likely diagnosis?

• Multiple system atrophy
• Parkinson’s disease
• Normal pressure hydrocephalus
• Urinary tract infection
• Pick’s disease

Answer 6

Normal pressure hydrocephalus

REMEMBER = urinary incontinence + dementia + gait abnormality

It isn’t multiple systems atrophy because:

• You don’t get dementia in multiple systems atrophy.
• You would get cerebellar signs (which are not seen in Parkinson’s)