CSF Physiology, Pressure & Dynamics
Raised intracranial pressure
Raised intracranial pressure is abnormally high pressure inside the skull, a key concern in active hydrocephalus.
In short: Raised intracranial pressure
- It is abnormally elevated pressure within the skull.
- It causes characteristic symptoms and signs.
- It can be dangerous if severe or rapid.
- Relieving it is a central goal of treatment.
What it is
Raised (or increased) intracranial pressure is abnormally high pressure inside the skull. In hydrocephalus, it most often results from the buildup of cerebrospinal fluid that cannot flow or be absorbed normally.
Understanding Raised intracranial pressure
Because the skull is an enclosed space, accumulating CSF raises the pressure on the brain. Symptoms and signs include headache (often worse in the morning or when lying down), nausea and vomiting, drowsiness or decreased alertness, double vision (from a sixth nerve palsy), and, on eye examination, papilledema (swelling of the optic nerve heads). In infants, the still-expandable skull shows a bulging fontanelle, splayed sutures, and rapidly increasing head circumference. Severe or rapidly rising pressure is dangerous and requires urgent treatment to relieve it.
Why it matters
Understanding raised intracranial pressure helps families and patients recognize the warning signs and see why relieving the pressure — through a shunt, ETV, or other measures — is a central and sometimes urgent goal of treatment.
Common questions
What causes raised pressure in hydrocephalus?
The buildup of cerebrospinal fluid.
What are the signs?
Headache, vomiting, drowsiness, double vision, and papilledema; in infants, a bulging fontanelle and rapid head growth.
Is it dangerous?
It can be, especially if severe or rapidly rising.
Bottom line
Raised intracranial pressure is abnormally high pressure in the skull, producing characteristic warning signs and requiring treatment to relieve it.
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