The brain sits in a fluid filled cavity above the paranasal sinuses. The fluid helps to absorb shocks and trauma to the brain. The intracranial cavity is separated from the sinuses by a paper thin sheet of bone called the skull base. Sometimes, there are small defects in this barrier due to trauma or natural causes that allow the fluid around the brain (cerebrospinal fluid) to leak into the sinuses and nasal cavity.
Patients with this problem may have intermittent or constant clear nasal drainage. They may also have headaches or other neurologic symptoms. This condition is serious because it can put the patient at risk for meningitis, a life-threatening infection of the brain. Patients with CSF leak need urgent endoscopic CSF leak repair.