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Cerebrospinal fluid leak (CSF Leak)

Mother and daughter

This is when fluid around the brain leaks into the nose. A sign of a CSF leak is clear, watery drainage leaking from the nose, usually just from one side. It may get worse when straining or bending forward. In most cases the cause is unknown, but it may be caused by an injury.

To diagnose a CSF leak, a doctor collects some of the draining fluid for a lab test. The fluid is tested for a protein called beta-2 transferrin, which is only present in CSF. In addition, radiology studies are also needed. Often, a CT scan is all that is needed. In some cases, an MRI or even a cisternogram is also needed. These studies helps show the exact location of the CSF leak. Then the CSF leak should be surgically corrected because there is a risk of meningitis – an infection of the membranes surrounding the brain. Your ENT doctor will explain the details of this procedure.