Cerebrospinal Fluid (CSF) Rhinorrhea

Cerebrospinal fluid (CSF) is a clear watery fluid surrounding the brain and the spinal cord. It is secreted by the choroid plexus of the ventricular system, and lesser amount is formed by capillary ultrafiltration and metabolic water production. Traumatic CSF rhinorrhea constitutes most of the cases of CSF rhinorrhea. Iatrogenic causes are rising due to the increasing rate of endoscopic skull base surgeries. Spontaneous resolution of iatrogenic CSF rhinorrhea is reported to be as low as 2% unlike accidental causes in which conservative treatment leads to spontaneous resolution in 85% of cases within a week. Spontaneous CSF leak is strongly associated with Idiopathic Intracranial Hypertension (IIH). Unresolved CSF leak has a 10% annual risk of developing meningitis and 40% over the long term. Different graft materials can be used for reconstruction, either synthetic or autologous. They can be placed underlay or overlay. However, experimental studies show that underlay becomes incorporated within the dura after the first week. Management of IIH is essential to avoid recurrence after surgery and includes weight loss, medical treatment, serial lumbar puncture, and surgical CSF diversion.