[A case of cerebrospinal fluid otorrhea 6 years after temporal bone fracture]

A 16 year-old female was admitted to our hospital because of left temporal bone fracture and brain contusion in the left temporal lobe. CSF otorrhea was also present for a week. Four years later, when she was 20 years old, she was noticed to have a white mass in the left external auditory canal. One and a half year later, left CSF otorrhea reappeared, and she was readmitted to our hospital. High resolution coronal CT revealed that the left temporal bone fracture had opened widely and brain tissue had herniated into the left external auditory canal. Metrizamide CT cisternography showed that CSF was leaking around the mass. Operative findings have shown that there were two dural defects, both of which were 2 cm in diameter, and brain tissue surrounded by arachnoid membrane had herniated through these defect. The herniated brain tissue was removed, and both dural- and osteo-plasty were successfully carried out. This case indicates that dissociation of temporal bone fracture and laceration of dura mater may cause herniation of brain tissue and CSF otorrhea years later.