Cerebrospinal Fluid (CSF) Leak
What it is
Your brain and spinal cord float in a cushion of clear fluid (cerebrospinal fluid) held in by a tough lining called the dura. A spinal CSF leak is a hole or tear in that lining that lets fluid escape, lowering the pressure around the brain. It can happen on its own, after a spinal procedure or injury, or where a small bone spur or cyst wears through the lining.
What it feels like
The most recognizable sign is a headache that is strongly positional: it comes on or worsens within minutes of standing or sitting up and improves when you lie flat. Some people also have neck pain, nausea, ringing or muffled hearing, or sensitivity to light. The upright-worse, lying-down-better pattern is the key clue.
How we diagnose it
The positional headache is often the biggest tip-off. Specialized imaging — a brain MRI with contrast and dedicated spine imaging — can show signs of low fluid pressure and, with more detailed studies, help locate the leak, which is not always easy to pinpoint.
How we treat it
Many leaks settle with conservative care: a period of lying flat, good hydration, and sometimes caffeine. When that is not enough, an epidural blood patch — placing a small amount of your own blood near the leak to seal it — is often very effective and can be repeated. For leaks that persist or have a clear structural cause, a targeted procedure or surgery to close the hole is considered. Most people get better.
The science — for the curious
The positional pattern makes sense once you picture the physics: when you stand, fluid that should be cushioning the brain is lost or shifted, the brain settles slightly, and that traction produces the headache; lying flat relieves it. Because leaks can be small and hard to localize, diagnosis sometimes takes patience and specialized imaging — but the outlook is good, since most leaks respond to a blood patch or, when needed, a focused repair.
Learn more
Spinal CSF Leak Foundation: spinalcsfleak.org
OrthoInfo — Neck Pain: orthoinfo.aaos.org
This handout is general education about a common condition and does not replace the personalized advice we discuss in clinic. If anything here does not match what we talked about, what we talked about wins — please ask me.