Causes & Risk Factors
Colloid cyst
A colloid cyst is a benign cyst that can block CSF flow at the foramen of Monro, causing hydrocephalus.
In short: Colloid cyst
- It is a benign cyst typically near the foramen of Monro.
- It can obstruct CSF flow from the lateral ventricles.
- It can cause hydrocephalus, sometimes acutely.
- It can be treated surgically, including endoscopically.
What it is
A colloid cyst is a benign (non-cancerous) fluid-filled cyst that typically forms in the region of the third ventricle, near the foramina of Monro. Despite being benign, its location can make it significant.
Understanding Colloid cyst
Because a colloid cyst often sits near the foramina of Monro — the channels draining the lateral ventricles — it can block CSF flow from these ventricles, causing hydrocephalus. In some cases this can develop acutely, producing sudden symptoms of raised pressure, which makes colloid cysts a recognized (though uncommon) cause of acute hydrocephalus. Treatment, when needed, involves removing the cyst, often through an endoscopic approach, which can relieve the obstruction. The decision to treat depends on the cyst's size, location, and whether it is causing problems.
Why it matters
Understanding colloid cysts helps families see how a small, benign cyst in a critical location can block CSF flow and cause hydrocephalus, and why removing it can relieve the obstruction.
Common questions
What is a colloid cyst?
A benign cyst typically near the foramen of Monro.
Why is it significant?
Its location can block CSF flow and cause hydrocephalus.
How is it treated?
By removing it, often endoscopically.
Bottom line
A colloid cyst is a benign cyst that can block CSF flow at the foramen of Monro, causing hydrocephalus, and can be removed surgically.
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