Causes of Hydrocephalus

Types and causes of hydrocephalus:

1-Obstructive hydrocephalus:

A-Communicating obstructive hydrocephalus.

Here the obstruction occurs distal to the site of the outlet foramina of the fourth ventricle.

Which means that obstruction will be in the level of sub arachnoid spaces or in the level of dural sinuses.

B-Non communicating obstructive hydrocephalus.

Here the obstruction site is at or proximal to the site of foramina of outlet of the fourth ventricle.

We have three stations for this type

*At the level of Foreman of Monroe:

If the foreman of Monroe is obstructed, the epsilateral lateral ventricle will be dilated while the rest of the ventricles will be of normal size.

*At the level of Aqueduct of Sylvius: 

Bilateral dilatation of the lateral ventricles and ballooning of the third ventricle.

*At the level of outlet foramina of fourth ventricle:

All the ventricles will be dilated with ballooning of the fourth and third ventricles.

2-Non obstructive hydrocephalus:

Caused by a tumor in choroid plexus excrete more CSF such as choroid plexus papilloma.