A case of bilateral eosinophilic granuloma in the temporal bone

We present a case of bilateral eosinophilic granuloma in the temporal bone in a 47-year-old woman, who visited our hospital with a headache and a feeling of occlusion in her left ear. Her left tympanic membrane was slightly turbid and pure tone audiometry revealed mild left sensorineural deafness. CT disclosed a shadow of soft tissue in the left mastoid antrum and mastoid cells, which was indicative of marked destruction of the bone. Because MRI findings led us to suspect otitis media cholesteatoma, a mastoidectomy was performed. The mastoid antrum and mastoid cells were filled with easily bleeding granulation, and there was a wide range of bone deficit in the posterior cranial fossa. Histopathologically, the granulation tissue was an eosinophilic granuloma. Her postoperative clinical progress was good and she was discharged. However 2 months after discharge, she had a feeling of occlusion in the right ear and CT revealed a shadow in the right mastoid antrum and cells. Therefore, right tympanoplasty was performed and the same findings as in the left ear were obtained. A histopathological diagnosis of eosinophilic granuloma was made again. To date, there has been no recurrence.