Cerebrospinal Fluid Leak

What is a cerebrospinal fluid leak?

Cerebrospinal fluid (CSF) leak occurs when there is a tear or hole in the membranes surrounding the brain or spinal cord, allowing the clear fluid that surrounds and cushions those organs to escape.

Cranial CSF leaks occur in the head and are associated with CSF rhinorrhea, in which the cerebrospinal fluid escapes through the nasal passages (runny nose).

Spinal CSF leaks develop due to tears in the soft tissues surrounding the spinal cord.

What causes a cerebrospinal fluid leak?

Some CSF leaks occur spontaneously and the cause is unknown, while others are a result of trauma such as a head injury, brain or spinal surgery, an epidural, a lumbar puncture (spinal tap) or a skull base tumor.

Patients with high-pressure hydrocephalus, an abnormal accumulation of cerebrospinal fluid, also may be at an increased risk of developing leaks.

What are the symptoms of a cerebrospinal fluid leak?

The most common symptoms of a spinal CSF leak are:

  • Positional headaches, which feel worse when sitting upright and better when lying down; caused by intracranial hypotension
  • Nausea and vomiting
  • Neck pain or stiffness
  • Change in hearing (muffled, ringing in the ears)
  • Sense of imbalance
  • Photophobia (sensitivity to light)
  • Phonophobia (sensitivity to sound)
  • Pain between the shoulder blades

For patients with cranial CSF leaks, the most common indicators are:

  • Drainage from the nose (rhinorrhea)
  • Salty or metallic taste in the mouth
  • Sense of drainage down back of throat
  • Drainage from the ear (otorrhea)
  • Cutaneous sinus tract drainage (CSF leaks into the sinus tract, which then creates a pathway to drain through the skin)
  • Loss of sense of smell (anosmia)
  • Change in hearing or ringing in the ears

Less frequently, patients with cranial CSF leaks experience cognitive changes.

How is a cerebrospinal fluid leak diagnosed?

Diagnosis of a CSF leak generally begins with a physical exam and history. A CSF leak can be difficult to detect, causing misdiagnosis or delayed diagnosis. Experts such as those in the Cedars-Sinai CSF Leak Program can be pivotal in providing relief.

If a cranial CSF leak is suspected, the patient’s physician may ask them to lean forward so they can observe if this increases the flow of nasal discharge. If the discharge can be collected, it is sent for laboratory tests to determine if it is cerebrospinal fluid.

The patient’s physician also may order tests to examine the condition of the brain and spinal cord. Whether the hole or tear is in the cranial area or the spine, the physician can order imaging tests to determine the exact location of the leak.

These tests may include:

A pledget test may be used to determine if a cranial CSF leak is occurring by placing small cotton pads (pledgets) in the nose.

The pledget test, however, cannot be used to determine the location of the leak. A CT scan, MRI, myelogram or a cisternogram can assist the physician in determining the location of the leak in either the cranial or spinal area.

How is a cerebrospinal fluid leak treated?

While many CSF leaks heal on their own and require only a period of bed rest, patients with symptoms of the condition should still visit their physician due to the increased risk of meningitis that is associated with cranial CSF leaks.

For cranial cerebrospinal fluid leaks that do not respond to conservative treatments, surgery may be necessary to repair the leak. The Cedars-Sinai Sinus Center has extensive experience in the use of nasal endoscopy, which is much less invasive than traditional surgical methods.

For spinal CSF leaks that do not respond to bed rest and other conservative treatments, an epidural blood patch or epidural patching with fibrin glue are treatment options. An epidural blood patch involves injecting the patient’s own blood into the spinal canal. The resulting blood clot then "patches" the hole where the leak is occurring.

If an epidural blood patch does not work, other surgical repairs may be necessary.

If high-pressure hydrocephalus is causing the CSF leak, the condition may reoccur until shunts are used to help drain the excess fluid.

Key points

  • Cerebrospinal fluid (CSF) leak occurs when there is a tear or hole in the membranes surrounding the brain or spinal cord, allowing the clear fluid that surrounds and cushions those organs to escape.
  • An increased risk of meningitis is associated with cranial CSF leaks.
  • CSF leaks can be cause by an injury, surgery, an epidural, a spinal tap or a tumor.
  • Many CSF leaks heal on their own, but others require surgical repair.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
  • Ask if your condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if you do not take the medicine or have the test or procedure.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.
© 2000-2022 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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