What to Know About Cerebrospinal Fluid (CSF) Leaks

Medically Reviewed by Christopher Melinosky, MD on May 12, 2023
Written by Shishira Sreenivas
5 min read

Cerebrospinal fluid (CSF) is a type of clear liquid that surrounds, protects, and cushions your brain and spinal cord from possible injuries. The fluid is held in place by the dura mater, a dense tissue that sits directly under the skull and makes up the outermost layer of the brain.

A CSF leak may occur if there’s a tear or a hole in the dura mater. There are two types of CSF leaks. If the fluid leaks from the brain such as with a skull fracture, it’s called a cranial CSF leak. If the leak occurs at any point along the spinal cord, it’s called a spinal CSF leak.

A leak may cause the brain to sag, which can lead to headaches. CSF leaks may also lower pressure within the skull, which could cause a condition called intracranial hypotension. If it persists, it can pull the brain down and tear bridging veins, causing a subdural hematoma.

CSF leaks are rare. According to experts, they happen to about five in every 100,000 people. But the number could be higher. They’re more common among people in their 30s and 40s.

In some cases, there’s no known cause for a leak. Doctors call this a spontaneous CSF leak. But there are known causes for the fluid to leak out, such as:

  • Lumbar puncture called a spinal tap
  • History of epidurals
  • Spinal catheters
  • Trauma or injuries to your head, neck or spine
  • Spinal surgeries
  • Epidural shot
  • Transsphenoidal surgery
  • Defects in the skull base, such as meningoencephaloceles
  • Abnormal CSF buildup in the brain, which increases the pressure
  • Untreated intracranial hypertension (high brain fluid pressure)
  • Connective tissue diseases such as Ehlers-Danlos and Marfan syndromes
  • Bone spurs in the spine
  • Headaches that may get worse when you sit or stand up -- the pain may come and go and get better when you lie down
  • Blurry or double vision, or changes in your field of vision
  • Dizziness
  • Ringing in your ears
  • Light sensitivity
  • Sound sensitivity
  • Balance issues
  • Neck stiffness and pain
  • Nausea
  • Vomiting
  • Pain between the shoulder blades
  • Arm pain
  • Loss of smell
  • Changes in mental cognition or behavior
  • Clear discharge from nose or ear
  • Metallic taste in your mouth

Women are more likely to have a CSF leak, as are people who have:

If you’ve noticed any CSF leak symptoms, tell your doctor about it right away. The doctor will first do a physical exam and take your medical history.

The physical exam may include:

  • An endoscopy of your nose, where a tube with a light and camera attached to it is passed through your nose to get a clear picture of possible issues
  • Your doctor may ask you to lean forward to check if you have drainage from the nose. If so, a sample is collected for a lab test.
  • Ear exam to check for CSF leaks

Your doctor may also order tests to check for problems in your brain or spinal cord. These tests may include:

  • CT scan
  • MRI
  • Myelography, an imaging procedure done on the spine
  • Cisternography, an imaging procedure done on the spine and brain

If left untreated, a CSF leak may cause complications like meningitis, which is a condition where the protective layers around the brain become inflamed. If it persists, it can pull the brain down and tear bridging veins, causing a subdural hematoma.

The hole or tear that causes the CSF leak may allow air to enter the space between the dura mater and the brain and spinal cord, causing a condition called pneumocephalus. If pressure builds up, you get tension pneumocephalus requiring emergency surgery. This usually occurs after trauma and is not spontaneous.

Sometimes, CSF leaks may be misdiagnosed as migraines, other headache conditions, or sinusitis.

Depending on the location and cause of the CSF leak, your treatment options may vary. For the first line of treatment, you doctor will suggest:

  • Bed rest for a couple of days
  • Hydration
  • Caffeine

If the first line of treatment doesn’t stop the leak, your doctor may suggest surgery to plug it.

Cranial CSF leak. If the leak is in the brain, surgical options to stem the leak may include nasal endoscopy. If the leak is in your ear, a microscope may also be used. To patch the tear or hole in the dura mater, your doctor may use things like:

  • Synthetic graft
  • Piece of tissue from your fat, muscle, or mucosal lining in various parts of your body
  • Flap of tissue
  • Surgical glue
  • Bony cement

If there’s too much fluid buildup in the brain, your doctor may also do a lumbar drain in the lower back to ease the pressure.

Spinal CSF leak. To stem the leak from your spinal cord, doctors may use treatments like:

  • Epidural blood patch, a treatment that injects your own blood into the spinal cord to form blood clots to stop the leak
  • Fat or muscle grafts
  • Stitches

If you’ve been diagnosed and treated for a CSF leak, during your recovery period, your doctor will suggest you take precautions for 4 to 6 weeks after the treatment.

These include:

  • Don’t lift anything heavier than 10 pounds.
  • Avoid bending, lifting, stretching, and twisting.
  • Don’t strain to have a bowel movement -- use a stool softener if necessary.
  • Avoid coughing and sneezing. If you need to cough or sneeze, do it with your mouth open to ease pressure.
  • If the CFS is leaking from your nose, avoid blowing your nose.
  • Don’t use straws.
  • Keep your back straight during all movements -- bend your knees and hips instead.