CSF Rhinorrhea

Also known as: cerebrospinal fluid (CSF) leak

Cerebrospinal fluid (CSF) rhinorrhea is the medical term for a rare condition in which the fluid that normally cushions the brain and spinal cord, cerebrospinal fluid, runs from the nose. For this to happen an abnormal path between the subarachnoid space of the brain and nasal/sinus cavities is inadvertently created. This abnormal space can be caused by:

• a nasal sinus surgery complication
• some birth defects
• severe obstructive sleep apnea which causes an increase in intracranial pressure (ICP)
• trauma to the head and face that causes a naso-orbito-ethmoid fracture and damage to the cribriform plate (a part of the frontal lobe that forms the "roof" of the sinus)

The exact incidence of CSF rhinorrhea is unknown but some studies have suggested that the rate of CSF rhinorrhea complications from sinus surgery is 0.5%. Thankfully, since the implementation of seat belt laws, the incidence of CSF rhinorrhea caused by trauma has declined.

Symptoms of CSF Rhinorrhea

Rhinorrhea (runny nose) that is clear and watery may be the first sign of cerebrospinal fluid rhinorrhea. Other signs and symptoms may include:

• headache
• nasal drainage with a salty or metallic taste
• drainage increases while leaning forward with head down
• lack of smell (anosmia)
• nasal congestion

It is important to realize that these symptoms also occur in many other, more common, conditions and should be evaluated by an otolaryngologist (ear, nose, throat specialist or ENT).

However if you have the symptoms listed above, you should not delay an evaluation since CSF rhinorrhea can lead to serious complications.

What to Do if You Suspect Cerebrospinal Fluid Rhinorrhea

If you are having the symptoms listed above, you should seek an evaluation by an otolaryngologist. If you had surgery, you should go to the surgeon that performed your procedure.

However, if you have not had nasal sinus surgery, you should obtain any CT scans or other radiographic images of your sinuses that you may have had in the past and take them to an ENT specialist for evaluation.

During this appointment you may be asked to perform a Smell Identification Test to determine if there is olfactory (smell) dysfunction. This test should be done before any treatment in order to determine baseline function. Your doctor may perform an endoscopy, this involves the doctor using a tiny camera to visualize any abnormalities to the cribriform plate. Other testing that may be ordered by your doctor includes:

• CT scan
• MRI
• Β-2 transferrin assay (laboratory test on nasal drainage)
• Radioactive pledget scanning
• Intrathecal fluorescein

Treatment Options for Cerebrospinal Fluid Rhinorrhea

If you have cerebrospinal fluid rhinorrhea it is important for you to receive appropriate treatment to prevent meningitis or pneumocephalus (air in the cranial cavity). To cure cerebrospinal fluid rhinorrhea, surgery will be necessary.

The type of surgery required will depend on the cause of your condition (surgery, trauma, sleep apnea...). The surgical success rate is good, however complications may occur with any surgical procedure, especially those involving general anesthesia. You should discuss the risk versus benefits of having the surgery with your doctor and follow any instructions they give you regarding fasting the day before and day of your surgery and any instructions on how you should take care of yourself after the procedure.

While cerebrospinal fluid rhinorrhea is a rare condition, the complications (e.g. meningitis) can be serious and should not be taken lightly.

_Sources:

_{Goldenberg, D. & Goldstein, B.J. (2011). Handbook of Otolaryngology – Head and Neck Surgery. New York City, NY:Thieme Medical Publishers, Inc.}

_{Kuzniar, T.J., Gruber, B. & Gokhan, M.M. (2005). Cerebrospinal Fluid Leak with Meningitis Associated With Nasal Continuous Positive Airway Pressure Therapy. Chest. Accessed: March 11, 2012 from http://journal.publications.chestnet.org/article.aspx?articleid=1083773}