Hydrocephalus

Question 1

What is the average ICP?

Answer 1

8-15mmHg

Question 2

If a mass is present in the brain and the brain is pushing out CSF to make space for it. Where does it get pushed out through?

Answer 2

Foramen mangum

Question 3

How is cerebral perfusion pressure measured?

Answer 3

CPP = MAP - ICP

MAP = mean arterial pressure
ICP = intracranial pressure

Question 4

How would someone feel in the early signs of hydrocephalus?

Answer 4

• feel a bit off
• perfuse N+V
• ~papilloedema
• headache

Question 5

What is hydrocephalus?

What are the 3 main causes?

Answer 5

Build up of CSF in the brain either due to:

• Obstuction
• Increased production
• Communicating (decreased absorption)

Question 6

How do pupils appear with hydrocephalus?

Answer 6

Fixed dilated

Question 7

When managing raised ICP we need to loosen around the collar?
Why?

What else non-drug wise can we do to help the same thing?

Answer 7

Loosening anything around the collar allows for CSF to flow down the jugular foramen easier

Also..

• raise head of bed
• maintain midline position of head

Question 8

What happens once the patient reaches the point of decompensation?

Answer 8

Exponentially deteriorates and leads to herniation

Question 9

What drug is the management?

Answer 9

Diuretics - hypertonic saline

Mannitol - osmotic diuretic (this is gonna come up in exams I feel)

Question 10

What is the surgical intervention that can help?

Answer 10

VP shunt - shunted into the peritoneal cavity

Question 11

How does normal pressure hydrocephalus present?

Answer 11

In older patient (huge list of differentials)

• Dementia
• Urinary incontience
• Abnormal gait

Question 12

How does hydrocephalus appear on MRI/CT?

Answer 12

Enlarged ventricles full of fluid

Lost gray-white difference - can no longer see gyri and sulci

Question 13

OVERWEIGHT woman of child bearing age presents with extreme headache and visual disturbances.

What kind of hydrocephalus should be in ur DD?
How is it tested for and why is it so worrying?

Answer 13

IIP - idiopathic intracranial hydrocephalus

LP reducing symptoms (same as normal pressure hydrocephalus)

Can lead to permeant blindness if not monitored

Question 14

What is the sun setting sign?

Answer 14

Sclera on show above the iris - sign of raised ICP

Question 15

How can you differentiate between a scan of a normal atrophied brain and normal pressure hydrocephalus?

Answer 15

Atrophied brain will show signs of large gaps at edges and ventricles will be slightly larger

However with normal pressure hydrocephalus there will be more signs of atrophy at inferior of brain as brain will be pushing UP into the skull so make it look better at top

Question 16

What is the first line treatment for IIP?

Answer 16

Aggressive weight loss

Carbonhydralise inhibitors
Diuretics