Cerebrospinal fluid (CSF) is a clear, colorless liquid that surrounds the brain and spinal cord, providing cushioning and protection. CSF rhinorrhea is a medical condition where this fluid leaks from the skull through the nose. This can occur due to a fracture or injury to the skull, or as a result of a surgical procedure. Symptoms of CSF rhinorrhea include a persistent runny nose, clear drainage from the nose, headaches, and a salty or metallic taste in the mouth. If left untreated, CSF rhinorr