[Spontaneous cerebrospinal fluid otorrhea in a normal inner ear. A case report].

A 49-year-old male with spontaneous cerebrospinal fluid (CSF) otorrhea, an extremely rare condition, is presented as the third reported case in Japan. The patient visited us complaining of sudden hearing loss and fullness of the ear on the left side. A tegmen defect of the posterior cranial fossa and CSF leakage from the fistula into the mastoid air cells, but a normal inner ear, were found by means of metrizamide CT. The fistula was surgically occluded with fascia temporalis and an artificial bone with fibrin glue. The CSF otorrhea from the tegmen defect was successfully stopped by this procedure and no recurrence has been observed. We discuss this extremely rare disease in this paper.