Figure 2From: Non-allergic rhinitis: a case report and reviewEtiology of CSF Rhinorrhea. CSF leak can be attributed to the following causes: Accidental trauma from a closed head injury (44%), surgical trauma (29%), tumors (22%), spontaneously due to increased intracranial pressure (ICP) (3-4%, but in some series are as high as 15-20%) and congenital skull base deformities (rare)[8–10].Back to article page