Brain, Meninges & CSF Anatomy
Third ventricle
The third ventricle is a central, narrow ventricle connecting the lateral ventricles to the fourth ventricle.
In short: Third ventricle
- An ETV procedure creates a new drainage opening here.
- It sits in the brain's center.
- It is part of the CSF pathway.
- Its floor is the site of an endoscopic third ventriculostomy.
What it is
It is the central, narrow ventricle that connects the lateral ventricles to the fourth ventricle. It sits in the middle of the brain along the CSF pathway.
Understanding Third ventricle
In endoscopic third ventriculostomy (ETV), a surgeon makes an opening in the floor of the third ventricle to create an internal CSF drainage route — an alternative to placing a shunt for some children with hydrocephalus. Its central position in the CSF pathway makes it the target for this procedure.
Why it matters
Understanding the third ventricle helps families see how an ETV works — by creating a new drainage opening in its floor — and why it is an option for some children with hydrocephalus.
Common questions
Where is the third ventricle?
In the center of the brain.
What procedure involves it?
ETV (endoscopic third ventriculostomy).
What does that procedure do?
Creates a new internal CSF drainage opening in its floor.
Bottom line
The third ventricle is the central ventricle where an ETV creates a new drainage opening.
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