Ventricular System

Question 1

What is the CSF pathway?

Answer 1

Ventricles (choroid plexus) -> Subarachnoid space -> Arachnoid granulations (reabsorption)

Question 2

What structures does foramen of Monro connect?

Answer 2

Lateral ventricles and 3d ventricle

Question 3

What are the parts of lateral ventricles?

Answer 3

• Anterior horns - 2
• Posterior horns (Occipital) - 2
• Inferior horns (Temporal) - 2

Question 4

What structures do connect 4th ventricle with Subarachnoid space?

Answer 4

• Foramen of Luschka (up)

- Foramen of Magendie (down)

Question 5

What types of Hydrocephalus are there?

Answer 5

1) Noncommunicating
Obstruction of flow within ventricles; most commonly occurs at narrow points, e.g., foramen of Monro, cerebral aqueduct and/or openings of fourth ventricle

2) Communicating
Impaired CSF reabsorption in arachnoid granulations or obstruction of flow in subarachnoid space

-Normal pressure (chronic)
CSF is not absorbed by arachnoid villi (a form of communicating hydrocephalus), because of calcification. CSF pressure is usually normal (loss of neurons). Ventricles chronically dilated. Produces triad of dementia, apraxic (magnetic) gait, and urinary incontinence. Peritoneal shunt.

• Ex vacuo
  Descriptive term referring to excess CSF in regions where brain tissue is lost due to atrophy,
  stroke, surgery, trauma, etc. Results in dilated ventricles but normal CSF pressure.