What is Cerebrospinal Fluid?

By: Ritisha Debnath

Edited: Tarynn OCampo

Cerebrospinal fluid (CSF) is a clear liquid that surrounds and cushions the brain and spinal cord, providing protection from injury. It also helps maintain stable pressure in the central nervous system. A CSF leak occurs when the fluid escapes through a tear or hole in the dura mater, the protective membrane surrounding the brain and spine. These tears can develop after head injuries, spinal procedures such as lumbar punctures, or surgeries involving the brain, sinuses, or spine. Additionally, in some cases, the leak may occur spontaneously due to increased pressure inside the skull or weakness in the protective membranes. When the barrier around the brain is damaged, the fluid may drain through the nose, ears, or into surrounding tissues. 

Symptoms of CSF Leakage:

One of the most common symptoms of a CSF leak is a severe headache that worsens when standing and improves when lying down. Other symptoms can include clear watery drainage from the nose or ear, dizziness, neck pain, hearing changes, nausea, or vision problems. These symptoms occur because the loss of fluid changes the pressure around the brain and spinal cord.

Why is it Dangerous?

Although some leaks heal on their own, untreated CSF leaks can be dangerous. The loss of protective fluid can cause the brain to shift slightly within the skull, increasing the risk of injury. More importantly, the opening created by the leak can allow bacteria to enter the central nervous system, which may lead to serious infections such as meningitis. Because of these risks, doctors often recommend medical evaluation and treatment to seal the leak and prevent complications. A CSF leak can sometimes also be a symptom of other underlying problems, such as head trauma, tumors, structural abnormalities of the skull, or connective tissue disorders that weaken the membranes protecting the brain. Early diagnosis and proper care are important to protect the brain and maintain normal nervous system function. 

Mayo Clinic. (n.d.). Cerebrospinal fluid (CSF) leak: Symptoms and causes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/csf-leak/symptoms-causes/syc-20522246

Johns Hopkins Medicine. (n.d.). Cerebrospinal fluid (CSF) leak. Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/cerebrospinal-fluid-csf-leak

Cleveland Clinic. (n.d.). Cerebrospinal fluid (CSF) leak. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/16854-cerebrospinal-fluid-csf-leak