What happens when the fluid inside your skull has nowhere to go? What if the brain — floating in a cushion of cerebrospinal fluid that normally drains and recycles every few hours — is slowly being crushed by the very liquid meant to protect it? What if the headaches are not migraines, the vomiting is not a stomach bug, and the blurred vision is not tired eyes — but a skull filling with fluid that is pressing the brain against bone? That is hydrocephalus. Not rare. Not simple. And not forgiving when it is caught late.

He was three months old. His head was growing faster than the charts predicted. His fontanelle — the soft spot on top — was bulging instead of flat. His eyes were drifting downward, showing white above the irises in a pattern doctors call the setting-sun sign. His mother thought he was just a big baby. The health visitor measured his head circumference three times before referring him. The ultrasound showed the ventricles swollen with cerebrospinal fluid—fluid being produced but not drained, backing up inside the brain like water behind a blocked pipe. By the time the neurosurgeon placed a shunt, the pressure had already damaged tissue that a three-month-old brain could not afford to lose. He survived. But the delay cost function that earlier detection would have saved.

This guide explains hydrocephalus with the seriousness it demands. How fluid builds, what the pressure does to the brain, who is at risk, what the symptoms look like, how diagnosis works, and how the right clinical equipment supports the detection that catches hydrocephalus before the damage is done. Medigear supplies certified diagnostic and monitoring equipment to hospitals and clinics across the UK — because hydrocephalus, when caught early, is treatable. Caught late, the brain pays a price no shunt can refund.

CSF and the Brain

The brain produces roughly five hundred millilitres of cerebrospinal fluid every day. CSF is made in the choroid plexus, inside the four chambers deep within the brain. It flows through narrow channels. Surrounds the brain and cord. Cushions. Nourishes. Cleans. It drains into the blood through arachnoid granulations. The system runs on balance. Production equals drainage. Hydrocephalus breaks that balance. Too much made. Too little drained. Or a block in between. Fluid backs up. Ventricles swell. The brain — trapped in a skull that cannot expand — gets crushed against its own walls.

Obstructive Hydrocephalus

Obstructive hydrocephalus — also called non-communicating — happens when a blockage stops CSF from flowing between the ventricles or out of them. A tumour on the aqueduct. A cyst in the fourth ventricle. The baby was born with a channel that was too narrow. Fluid builds behind the block. Ventricles swell. Pressure climbs. Physical block. Surgical answer — remove it or build a new path.

Communicating Hydrocephalus

Communicating hydrocephalus happens when CSF flows freely through the ventricles but is not absorbed properly. The drain holes are damaged, scarred, or overwhelmed. It follows meningitis, brain bleeding, or head injury. Fluid moves but never leaves. Ventricles swell. Brain shrinks. Symptoms creep in over weeks or months. So slowly that both patient and doctor blame something else.

Normal Pressure Hydrocephalus

Normal pressure hydrocephalus — NPH — is the form that hides in old age. Ventricles enlarge. Pressure on a single tap may look normal. But the brain is still being damaged. The classic triad — trouble walking, incontinence, and cognitive decline — mimics dementia, Parkinson's, and ageing itself. NPH is one of the few causes of dementia that can be treated. A shunt can reverse the symptoms — but only if hydrocephalus is diagnosed. Thousands are missed every year because the symptoms look like getting old.

Babies

Babies with hydrocephalus show it differently from adults. Skull bones have not fused. Fontanelles still open. So the head expands instead. Rapidly. A head crossing centile lines upward is the earliest sign of hydrocephalus. Bulging fontanelle. Vomiting. Irritability. Drowsy feeding. Setting sun sign — eyes forced down by pressure on the nerves. Congenital hydrocephalus affects roughly one in a thousand births. Causes include spina bifida, a narrow aqueduct, pregnancy infection, or brain bleeding in preterm babies.

Adult Symptoms

Symptoms in adults and older children present as rising intracranial pressure. Headache — worse in the morning, lying down, or straining. Nausea. Vomiting. Blurred or double vision from pressure on the eye nerves. Drowsiness sliding into reduced consciousness. Papilledema — swelling of the optic disc on fundoscopy — confirms elevated intraocular pressure. Acute hydrocephalus is a neurosurgical emergency. Chronic presents slowly — but the damage builds just the same.

Linked Guides

For hospitals managing hydrocephalus alongside broader monitoring, our guide to the best nebulisers covers the respiratory devices that support post-operative neurosurgical patients — because a baby or adult recovering from shunt surgery may need respiratory support during the critical first days. Our guide to patient monitoring on a budget covers the vital signs tools that track neurological observation — because GCS scoring, pupil checks, and heart rate monitoring after shunt insertion require continuous bedside tracking.

Diagnosis

Diagnosis combines clinical suspicion with imaging. In babies, cranial ultrasound through the fontanelle shows ventricle size. No radiation. In older children and adults, CT shows swollen ventricles quickly — often in A&E. MRI shows the detail — the cause, the degree, and the brain tissue around it. Lumbar puncture measures pressure. In NPH, removing 30 to 50 mils and checking whether walking or thinking improves is both a test and a preview of treatment.

VP Shunt

Treatment for most cases of hydrocephalus is surgical. A ventriculoperitoneal shunt (VP shunt) drains CSF from the ventricles through a tube under the skin into the peritoneal cavity, where the body absorbs it. The shunt has a valve. Controls flow. Prevents overdrainage. Shunts save lives. But they fail. Block. Disconnect. Migrate. Infect. A child shunted in infancy may need multiple revisions over a lifetime. Shunt dependence is not a cure. It is a compromise — a brain that cannot drain and a device that can.

ETV

Endoscopic third ventriculostomy — ETV — is the shunt-free alternative for obstructive hydrocephalus. The surgeon makes a hole in the floor of the third ventricle with an endoscope. CSF bypasses the block and reaches the drain sites directly. No hardware. No device to fail. But ETV does not suit every patient. The hole can close over time — bringing back the hydrocephalus and the pressure with it.

Shunt Infection

Shunt infection is the complication that every neurosurgical team watches for. Bacteria — usually skin organisms from surgery — colonise the tubing. Fever. Irritability. Shunt failure. Sometimes meningitis. Treatment means removing the shunt, administering IV antibiotics, and replacing it once the infection is cleared. In a baby, weeks in hospital, multiple operations, and damage stacked on the damage that hydrocephalus already caused.

Living With It

Living with hydrocephalus means living with uncertainty. Will the shunt block tonight? Will the headache that started this morning be a migraine or a malfunction? Will the child who seems well today need another operation next month? Parents of children with shunts carry a constant low-level fear that healthy families never experience. Adults with NPH who improve after a shunt live wondering how long the improvement will last. Mental health support — for patients and for families — belongs in every hydrocephalus pathway.

Head Circumference

Can your paediatric team measure head circumference at every check and act on a crossing centile — not at the next appointment but now? A head growing too fast is hydrocephalus until proven otherwise. A referral that waits two weeks while the ventricles swell is a referral that arrives after the damage. Measure. Plot. Act. The tape measure is the cheapest diagnostic tool in hydrocephalus — and the one that catches it first.

Emergency CT

Does your emergency department have CT access fast enough for acute hydrocephalus? A patient with sudden headache, vomiting, and dropping consciousness needs imaging within minutes — not hours. The scan that shows swollen ventricles and a trapped fourth ventricle triggers the call to neurosurgery. The scan that waits until the morning shift triggers nothing the patient can use.

School Plan

School life for a child with a shunted hydrocephalus needs a plan that most schools have never written. Staff trained on shunt malfunction signs — headache, vomiting, drowsiness, change in behaviour. An emergency protocol that does not wait for the morning. Activity guidance for PE and playground. And a teacher who knows that the child who seems well between episodes carries a device inside their skull that can fail without warning. One plan. Known by every adult in the room. Not filed in a drawer. Because the shunt does not send a warning before it fails. The child just changes. And the adult who notices first saves what the delay would cost.

Why Choose Medigear

Medigear supplies certified diagnostic and monitoring equipment — including vital signs monitors, pulse oximeters, and clinical accessories — to hospitals, neurosurgical units, and clinics across the UK. Whether you are equipping a paediatric ward, upgrading monitoring for post-operative neurosurgery, or building diagnostic readiness for neurological presentations, our team matches the right tools to your clinical need. Reach out to our team directly for guidance built around the patients whose brains are under pressure — and the clinicians who relieve it before the damage is done.

Conclusion

What happens when the fluid inside the skull has nowhere to go? The ventricles swell. The brain compresses. And a three-month-old baby whose head grew too fast loses brain tissue that no shunt placed two weeks later can give back. Hydrocephalus does not wait for the next appointment. It does not pause while the referral sits in a queue. It builds — silently, steadily, and without mercy — inside a skull that cannot expand to make room. A tape measure at every check. A scan within minutes when the signs appear. A shunt or an ETV before the pressure crosses the line. That is how hydrocephalus is caught before the damage is done. Medigear stands alongside neurosurgical and paediatric teams with certified monitoring equipment and the honest support that brain pressure demands. Speak to our team today — because the brain under pressure needs tools as fast as the fluid that is building against it.

⚠️ This post is for general information only. We do not sell medications or provide prescriptions — Medigear.uk is a medical equipment supplier only.