Cerebrospinal Fluid (CSF) Leak

A cerebrospinal fluid (CSF) leak is when the fluid surrounding your brain and spinal cord leaks out from where it’s supposed to be. It happens when there’s a tear or hole in the dura mater. This is the outer layer of the protective membrane (meninges) that surrounds your central nervous system.

The most common symptom is a headache. You may also have other symptoms that can vary depending on whether the tear is near your brain or spinal cord.

CSF cushions and protects your brain and spinal cord. Too much fluid loss can be dangerous. It may lead to brain injuries or infections. Some complications can be life-threatening.

Types of CSF leaks

There are two types of cerebrospinal fluid leaks based on location:

• Cranial CSF leak: This leak happens in your skull near your brain.
• Spinal CSF leak: This leak happens in your spine near your spinal cord.

CSF leak symptoms

CSF leak symptoms vary based on where they are and how severe they are. In some cases, if you have a small leak, you may not notice any symptoms or you might mistake the symptoms for something else. If anything doesn’t seem right, contact a healthcare provider. CSF leaks can be serious.

Cranial CSF leak symptoms

Common symptoms of a leak near your brain may include:

• Ear drainage
• Headache
• Limb weakness
• Loss of sense of smell
• Neck pain or stiffness
• Nose drainage (clear and wet, not like mucus)

Spinal CSF leak symptoms

Common symptoms of a leak near your spinal cord may include:

• Blurred vision or double vision
• Brain fog
• Dizziness
• Headache that gets worse when you stand up but improves when lying down (positional headache)
• Memory issues (severe cases)
• Muscle weakness
• Nausea
• Neck pain or stiffness
• Pain radiating from your spine
• Ringing in your ears

CSF leak causes

Most cerebrospinal fluid leaks happen after an injury. Common injuries may include:

• Crushing injuries
• Twisting or severe whiplash
• Puncture, stab or gunshot wounds

Some leaks may happen after:

• Brain surgery or spine surgery
• Ear, nose or throat procedures
• Spinal tests or procedures (lumbar puncture or epidural)

In fewer cases, a leak may happen without an injury. Sometimes, it’s linked to health conditions you’re born with that affect the membrane that holds CSF.

Risk factors

Anyone can develop a CSF leak, especially if you have had a recent injury. You may be more at risk if you have:

• A connective tissue condition like Marfan syndrome or Ehlers-Danlos syndrome
• High pressure in your skull (intracranial hypertension)
• Structural issues with your nose, sinuses or skull

Spontaneous leaks, those that happen without an injury, are more common in women between age 33 and 52.

Is a CSF leak life-threatening?

Yes, some severe leaks can be life-threatening. CSF cushions your brain and spinal cord. It protects them from injury. When you lose too much fluid, your brain can sag or shift inside your skull. This increases your risk of injury, potentially leading to permanent brain damage.

A leak also raises your risk of serious infections like meningitis. This is a dangerous infection of the protective layers around your brain and spinal cord. Meningitis is a medical emergency that requires immediate treatment.

How doctors diagnose a CSF leak

A healthcare provider can diagnose a cerebrospinal fluid leak using a physical examination, along with gathering information about your symptoms. They’ll also ask you questions about your medical history.

Testing confirms a diagnosis. The type of testing may vary based on the location of the leak.

• Cranial CSF leak: Fluid testing from your nose or ear (beta-2 transferrin test) and imaging tests of your head, like a CT scan, MRI, cisternogram scan and/or fundoscopy
• Spinal CSF leak: Imaging tests, like a brain and spine MRI and/or a myelogram

Special diagnostic tests like DSM (digital subtraction myelography) or DSA (digital subtraction angiography) may be required in complex cases.

How to test for a CSF leak at home

A CSF leak isn’t something you can diagnose or treat on your own. If you suspect you have this condition, you should talk to a healthcare provider as soon as possible.

CSF leak treatment

Your provider will give you specific instructions to follow if you have a cerebrospinal fluid leak. These can vary based on the location and severity.

In some cases, they may recommend bed rest. This is to let the cranial or spinal leak injury heal on its own. Your provider may also recommend that you stay hydrated, avoid caffeine and take either over-the-counter medications or prescribed medications to relieve symptoms.

Your provider may also recommend avoiding pressure triggers, like sneezing or coughing. This can be easier said than done, we realize. But you can lower your risk by staying away from dust, allergens or high-pollen areas, especially if you know you’re sensitive to them.

Cranial CSF leak treatments

Minimally invasive procedures to treat CSF leaks near your brain may include:

• External ventricular drain: A drain placed in your brain’s ventricles to help relieve pressure
• Lumbar drain: A tube inserted in your lower back to reduce CSF pressure in your head
• Nasal packing: Absorbent material placed in your nose to prevent leaks
• Shunt: A shunt redirects fluid from your brain to another part of your body to relieve pressure

Some cranial CSF leaks need surgery to stop problems from happening. These may include:

• Bone grafting: Your surgeon may use bone from another part of your body or a synthetic material to improve a structural abnormality.
• Endoscopic endonasal repair: This is a procedure performed through your nose that seals the leak.
• Open surgery: This is an invasive procedure where a surgeon opens your skull to repair the leak.

Spinal CSF leak treatments

Your provider may recommend one of the following treatments for a CSF leak around your spinal cord:

• Epidural blood patch: Your provider will inject a small amount of your blood into the space around your spinal cord to seal the leak.
• Lumbar drain: A temporary tube drains excess fluid to reduce pressure and help the leak heal.
• Dural repair surgery: This is a surgical procedure to directly seal the tear in the protective covering.

CSF leak recovery time

Your provider will give you the best advice on what your recovery time looks like. You may need a few days of rest to feel better. If you had surgery, you may need several weeks to months to fully heal.

When should I see my healthcare provider?

You should talk to or see a healthcare provider if you think you have a leak. The first symptom is usually a headache (for cranial and spinal types) and a runny nose that doesn’t produce mucus (for the cranial type), among other symptoms.

If you have a known leak and you’re receiving treatment, let your provider know if you have new or worsening symptoms.

When should I go to the ER?

If you have a cranial CSF leak and you notice the following sudden symptoms, visit the emergency room:

• Severe headache
• Slurred speech
• Facial drooping
• Vision loss
• Difficulty swallowing
• Trouble thinking clearly
• One-sided weakness or paralysis

The following sudden spinal CSF leak symptoms may require emergency medical attention:

• Tingling or numbness in your hands, arms, feet or legs
• Difficulty standing
• One-sided weakness or paralysis
• Muscle weakness

What can I expect if I have a CSF leak?

Most CSF leaks get better with rest or surgery. But they can come back, even after healing.

Cerebrospinal fluid leaks are unpredictable and can’t always be prevented. Still, you may be able to lower your risk of injury-related causes. Wearing protective gear is the best way to do this. Head, neck, back or facial trauma may lead to a leak. Use personal protective or safety equipment at work and during daily activities when applicable.