Core Terms & Classification
Internal hydrocephalus
Internal hydrocephalus refers to the accumulation of cerebrospinal fluid within the ventricles inside the brain.
In short: Internal hydrocephalus
- It describes fluid buildup within the ventricular system.
- It is the form most people mean by "hydrocephalus."
- It contrasts with external hydrocephalus (fluid in spaces outside the brain).
- It is identified on imaging.
What it is
Internal hydrocephalus is the accumulation of CSF within the ventricles inside the brain — the form of hydrocephalus that most people are referring to when they use the term. The "internal" emphasizes the location within the ventricular system.
Understanding Internal hydrocephalus
Because the ventricles sit deep within the brain, internal hydrocephalus involves enlargement of these inner fluid spaces. It is distinguished from external hydrocephalus, in which fluid accumulates in the spaces surrounding the brain (the subarachnoid spaces). The distinction helps describe where the fluid is building up, which can be relevant to the cause and the approach to care.
Why it matters
Understanding internal hydrocephalus helps families interpret descriptions that specify fluid buildup within the ventricles, and distinguish it from external forms. It clarifies the location of the problem.
Common questions
What is internal hydrocephalus?
Fluid buildup within the ventricles inside the brain.
Is it the usual meaning of hydrocephalus?
Yes — it is the form most people mean.
How does it differ from external hydrocephalus?
Internal involves the ventricles; external involves the spaces around the brain.
Bottom line
Internal hydrocephalus is fluid buildup within the brain's ventricles, the form most people mean by hydrocephalus.
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