Pseudo-cerebrospinal fluid rhinorrhea after skull base surgery.

A 41-year-old female underwent complete resection of a left petroclival meningioma via an anterior transpetrosal approach, during which the greater superficial petrosal nerve was divided. On the 14th day after the operation, she first noticed leakage of clear fluid from her right nostril whenever the ambient room temperature rose. This pseudo-cerebrospinal fluid rhinorrhea may have developed because of parasympathetic hypersensitivity due to division of the greater superficial petrosal nerve.