Specific Types & Syndromes
Isolated (trapped) lateral ventricle
An isolated lateral ventricle is a lateral ventricle cut off from the rest of the CSF pathways, which can enlarge on its own.
In short: Isolated (trapped) lateral ventricle
- One lateral ventricle becomes isolated from the CSF pathways.
- It can enlarge independently.
- It often results from a blockage at the foramen of Monro.
- It may be treated by connecting it to the other ventricle (septostomy).
What it is
An isolated (or trapped) lateral ventricle is a lateral ventricle that has become cut off from the rest of the CSF pathways, usually by a blockage at its foramen of Monro, so it accumulates fluid and enlarges independently. It is a form of compartmentalized hydrocephalus.
Understanding Isolated (trapped) lateral ventricle
When one lateral ventricle is isolated — for example, by scarring or a blockage at the foramen of Monro — fluid produced within it cannot drain normally, and it enlarges on its own (unilateral hydrocephalus). This can press on surrounding brain tissue. Treatment may involve creating an opening in the septum pellucidum (septostomy) to connect the isolated ventricle to the other lateral ventricle so they drain together, or placing a catheter into the isolated ventricle. The approach depends on the specific anatomy and is individualized. Isolated ventricles are part of the complex landscape of compartmentalized hydrocephalus.
Why it matters
Understanding the isolated lateral ventricle helps families see how one ventricle can become trapped and enlarge, and why treatment may involve connecting it to the rest of the CSF system, such as with a septostomy.
Common questions
What is an isolated lateral ventricle?
A lateral ventricle cut off from the CSF pathways.
What usually causes it?
A blockage at the foramen of Monro.
How is it treated?
Often by connecting it to the other ventricle (septostomy).
Bottom line
An isolated lateral ventricle is a trapped, enlarging ventricle often treated by connecting it to the other ventricle via septostomy.
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