Your brain is responsible for everything from thought and emotion to regulation of cardiovascular and respiratory systems. Because of the brain’s vital importance, your body has a built-in protection system: The brain and the spinal cord are surrounded by three layers of membranes and tissues known as meninges, and within those layers is cerebrospinal fluid.
“Cerebrospinal fluid cushions the brain and protects it during trauma,” says Nicholas Thompson, MD, a UNC Health otolaryngologist, also called an ear, nose and throat doctor.
This clear, watery fluid fills the ventricles, or cavities, within the brain and continuously circulates throughout the central nervous system. When there is a tear or a hole in the outermost membrane around the brain, the cerebrospinal fluid can leak.
We talked to Dr. Thompson about what causes these leaks, the symptoms they create and how they’re treated.
Causes and Symptoms of Cerebrospinal Fluid Leaks
Cerebrospinal fluid leaks may be caused by head injuries, such as those sustained in a car accident or a fall. A leak can also happen during a surgical procedure near the brain or the spinal cord, including sinus and ear surgeries, epidurals and lumbar punctures.
Spontaneous leaks—ones that can’t be tied to a head trauma or a medical procedure—also occur, though they are rare. Dr. Thompson says conditions such as obesity and sleep apnea can occasionally create increased pressure in the brain, leading to a leak. People with connective tissue disorders also may be at higher risk for a tear.
The symptoms of a cerebrospinal fluid leak include drippage of fluid from the nose, a feeling of fullness in the ear, decreased hearing, headaches, neck pain or stiffness, and sensitivity to light.
“The nasal leak tends to be more intense than a runny nose,” Dr. Thompson says. “For people who have this symptom, the nose can drip like a faucet if they lean forward.”
If you begin to experience these symptoms after a surgery or a head injury, you should report them to your doctor.
“The onset of symptoms will happen fairly quickly,” Dr. Thompson says. “Most people show them in the first several days after the surgery or head trauma.”
For spontaneous leaks, it may be more difficult to tie the symptoms to the cause. “The fluid often stays in the middle ear space, so if your ear feels full for longer than a few months, talk to a doctor,” Dr. Thompson says.
During a leak, there is an increased risk of meningitis, an inflammation of the membranes.
“If there’s bacteria in the nose or ear, it will have an easier connection to the membranes when the leak is unrepaired,” Dr. Thompson says.
Diagnosis and Treatment of Cerebrospinal Fluid Leaks
If you are experiencing a persistent nasal drip, a fluid specimen will be collected and tested for beta-2-transferrin, a protein found in cerebrospinal fluid. Your doctor also may be able to see the fluid during an ear exam. Diagnosis of a cerebrospinal fluid leak can also be made via imaging, such as a CT scan or an MRI.
It’s possible for cerebrospinal fluid leaks to resolve on their own.
“If the cause is a trauma like a car crash, then these leaks can often be addressed with conservative measures, like bed rest and avoiding straining during daily activity,” Dr. Thompson says. “If the cause is surgical, the person will usually need surgery to repair the site of the leak.”
The surgery required will depend on the size and location of the leak; some leaks can be stopped through minimally invasive procedures, while open surgery is sometimes required.
Concerned about the health of your head and neck? Talk to your doctor. Need a doctor? Find one near you.