What Is a CSF Shunt?

If you or your child has just been told that hydrocephalus needs treating, the word "shunt" tends to arrive quickly — and it can sound more alarming than it needs to. A shunt isn't a cure for hydrocephalus, and it doesn't remove anything. It's a small drainage system: a set of thin, soft tubes with a valve that moves extra cerebrospinal fluid (CSF) away from the spaces inside the brain to another part of the body, where the fluid can be absorbed.

Your brain and spinal cord are surrounded by CSF all the time. It cushions, it carries nutrients, and it's constantly being made and reabsorbed. Hydrocephalus happens when that balance breaks down — fluid builds up faster than it drains, the fluid spaces (ventricles) inside the brain enlarge, and pressure can rise. A shunt gives the fluid another way out. Our overview of hydrocephalus explains the condition itself in more detail.

The short video at the top of this page, "CSF shunt Insertion", runs just over a minute and shows a shunt being inserted. It's brief, but it gives you a real sense of the operating-room setting before we walk through what to expect.

Before the operation: what the team is planning

Most shunt surgery is planned rather than rushed, which means you'll usually have time to ask questions. The team will explain which type of shunt they're proposing. The most common arrangement drains fluid from a ventricle in the brain to the abdomen — a ventriculoperitoneal (VP) shunt — where the fluid is absorbed into the bloodstream. Other routes exist, and the valve itself may be fixed-pressure or adjustable (programmable) from outside the skin with a magnet; which one suits you depends on why the hydrocephalus developed and on your scans.

Expect imaging beforehand, usually a CT or MRI scan, so the surgeon can plan where the tube enters the ventricle. You'll also be told about fasting before the anaesthetic, and — this is worth knowing in advance — a small patch of hair is typically shaved where the incisions will be. People are often more bothered by surprises than by the procedure itself, so ask about anything that would otherwise catch you off guard.

During surgery: what actually happens

You'll be asleep under a general anaesthetic for the whole operation, so you won't feel or remember it. In outline, the surgeon makes a small incision in the scalp and a small opening in the skull, then passes a thin tube (a catheter) into a ventricle. That tube connects to the valve, which usually sits under the skin behind or above the ear — you may be able to feel a small bump there afterwards, and that's normal.

From the valve, a second catheter is tunnelled under the skin, down the neck and chest, to its end point — for a VP shunt, the abdomen, through a small incision there. Once everything is connected, CSF can flow through the system whenever pressure in the ventricle rises above the valve's setting, and the valve helps stop it flowing back the wrong way.

A second video on this site, "Insertion of a CSF shunt", also runs about a minute and focuses on the abdominal end of the operation — its description makes the point that closing the abdominal wall well matters, because some patients need abdominal surgery more than once over a lifetime with a shunt. That long view is a useful thing to carry into your own follow-up care.

After surgery: the first days, and going home

When you wake up, expect a headache and some soreness around the incisions to be common at first — tell the team how you feel, because how your symptoms change is one of the things they're watching. You'll usually have a scan after surgery to check the catheter positions and the size of the ventricles, and the team will check that you're moving, eating, and thinking as expected before you go home.

At home, the practical rules are simple ones. Keep the wounds clean and dry and follow the instructions you were given about washing and hair washing. Take things gently at first, and go to every follow-up appointment, even when you feel completely well — shunt follow-up continues long after the wounds have healed, because the shunt is a long-term device, not a one-time fix.

Living with a shunt: the part that matters most

Here's the honest part, and every shunt patient should hear it plainly: a shunt is a mechanical device, and mechanical devices can stop working as they should. A shunt can become blocked, it can drain too much or too little, tubing can wear or break over time, and the system can become infected. None of that means yours will — many people live for years with the same shunt — but it does mean you should know the warning signs and act on them quickly rather than waiting to see.

Learn the pattern of your own hydrocephalus symptoms, and tell your team promptly about a return of those symptoms: a headache that doesn't settle, vomiting, unusual sleepiness or confusion, changes in vision, or — in babies — a rapidly growing head, a bulging soft spot, or unusual irritability. Redness, swelling, or pain along the line of the tubing under the skin, or a fever, is also worth reporting the same day. Shunt problems are very treatable when they're caught, especially when the team hears about them early.

Day to day, though, most people with a shunt simply get on with life — school, work, travel, and ordinary activities — with follow-up scans and clinic visits fitted around it. If your valve is a programmable type, mention your shunt before any MRI scan, because the scanner's magnet can change some valves' settings; many people carry a shunt card or medical alert for exactly that reason.

So if you're heading into this surgery, hold on to three things: the shunt is there to drain fluid your body can't shift on its own, the operation itself is usually only part of a day, and your real job afterwards is simply to know your warning signs and use them. That's a manageable brief — and it's how shunt patients and their teams keep a small device doing its quiet work for years.

References & further reading

MedlinePlus — Hydrocephalus: https://medlineplus.gov/hydrocephalus.html

MedlinePlus Medical Encyclopedia — Hydrocephalus: https://medlineplus.gov/ency/article/001571.htm

NHS — Hydrocephalus: https://www.nhs.uk/conditions/hydrocephalus/

Hydrocephalus Association — About Hydrocephalus: https://www.hydroassoc.org/about-hydrocephalus/

Frequently Asked Questions

Is a CSF shunt permanent?

It's intended as a long-term device, and for most people hydrocephalus needs lifelong management. That said, parts of a shunt can be adjusted or replaced if it blocks, wears, or stops suiting you — a follow-up operation to revise a shunt is a recognised part of shunt care, not a sign that everything has failed.

Can you feel a shunt under the skin?

Often, yes — a little. The valve usually sits under the skin behind or above the ear, and the tubing runs under the skin of the neck and chest; some people can trace its line with a fingertip. It's normally not painful, and other people generally can't see it.

Does a shunt cure hydrocephalus?

No — it manages it. The shunt drains fluid around the underlying problem rather than removing its cause, which is why follow-up continues even when you feel well. Some people are candidates for a different operation instead, such as an endoscopic third ventriculostomy, and your surgeon can explain whether that applies in your case.

What should I do if I think my shunt isn't working?

Contact your neurosurgery team the same day, or seek urgent care if you have severe or worsening headache, repeated vomiting, unusual drowsiness, or vision changes. Don't wait for a routine appointment: shunt problems are much easier to sort out when they're assessed early.

MedicalVideos.com has published trusted medical videos since 2007. The site was founded by Dr. Mohamed Ibrahim, MD, PhD — physician-scientist.

Educational only — this article is general information about CSF shunts, not medical advice and not a diagnosis. Whether this treatment, or any treatment, is right for you is a matter for your own care team, who know your results and your history.