Neuroglial choristoma of the middle ear.

Neuroglial choristoma is a rare cerebral heterotopia which can involve various locations. Even if its occurrence is more frequent in midline structures, it can also be found in the non-midline structure such as, for example, even if only rarely, the middle ear. The described case is that of a 74-year-old male who had been operated on for a neuroglial choristoma located in the tympanic cavity and in the mastoid bone. High resolution computed tomography and intra-operative findings did not reveal any connection with the upper cerebral structures, thus excluding the hypothesis of an encephalocele. After careful histopathological examination, the aetiopathogenetic hypothesis are analysed. Only 8 similar cases have been reported in the literature.