Cerebrospinal fluid (CSF) rhinorrhea is a rare condition in which cerebrospinal fluid, which normally cushions the brain and spinal cord, leaks from the nose. CSF rhinorrhea symptoms include headaches and runny nose. It can also lead to meningitis, an infection of the lining around the brain tissue (meninges).

This condition can happen when an abnormal tear is inadvertently created between the subarachnoid space of the brain and the nasal sinus cavities—for example, during surgery or a trauma. Treatment includes preventing meningitis and possibly repairing a meningeal tear or a skull fracture.

This article reviews the symptoms, causes, and diagnosis of CSF rhinorrhea, as well as how it’s treated and why it’s so important to get symptoms evaluated promptly.

CSF Rhinorrhea Symptoms

Signs of CSF rhinorrhea can be subtle. A runny nose that is clear and watery may be the first symptom of CSF rhinorrhea.

Other signs and symptoms may include:

  • Headache
  • Salty or metallic taste in the mouth
  • Drainage increases while leaning forward with head down
  • Anosmia (lack of smell sensation)
  • Nasal congestion

These symptoms also occur with many other, more common conditions. However, given the potential complications of CSF rhinorrhea, you should not delay an evaluation if you experience them.

Causes of Cerebrospinal Fluid Rhinorrhea

A tear In the meninges or a fracture of bones in the region between the brain and the nasal cavities can allow CSF to leak from around the brain to the nostrils.

Some causes include:

  • Nasal sinus surgery
  • Developmental birth defects affecting the formation of the skull
  • An increase in intracranial pressure (ICP)
  • Trauma to the head or face that causes a naso-orbito-ethmoid fracture or damage to the cribriform plate (a part of the “roof” of the sinus)
  • An object entering the upper nasal cavity (such as a nasal swab or a toy)

Spontaneous CSF rhinorrhea—that is, of unknown cause—is also possible.

Diagnosis

You should see a healthcare provider promptly if you are having symptoms of CSF rhinorrhea. If you are having the symptoms after nasal surgery, you should call the surgeon who performed your procedure.

The exact incidence of CSF rhinorrhea is unknown, but it is considered a rare complication of sinus surgery. Since the implementation of seat belt laws, the incidence of CSF rhinorrhea caused by trauma has also declined.

During your evaluation, you may be asked to perform a Smell Identification Test to determine if you are having olfactory (smell) dysfunction.

Depending on your situation, your healthcare provider may also choose to perform an endoscopy. This involves using a tiny fiberoptic scope to visualize any abnormalities in the superior nasal cavity and cribriform plate.

Tests that may be ordered by your healthcare provider include:

  • Computerized tomography (CT)Magnetic resonance imaging (MRI)Β-2 transferrin assay (laboratory test on nasal drainage) to confirm whether the substance is in fact CSFRadioactive pledget scanning, an imaging test that involves inserting medical cotton in your nose and ears, followed by a lumbar punctureIntrathecal fluorescein can be used to both identify CSF leaks and to surgically repair them

Treatment

If you have cerebrospinal fluid rhinorrhea, it is important for you to receive appropriate treatment to prevent meningitis, which can be a very serious infection, and pneumocephalus (air in the cranial cavity).

Very small leaks may only require bed rest and medication to resolve. However, most cases of CSF rhinorrhea require surgery to repair the source of the leak. This is done by an otolaryngologist (ear, nose, throat specialist,

The type of surgery required will depend on the cause of your condition (surgery or trauma). The surgical success rate is good, though complications may occur with any surgical procedure.