Glial heterotopia of the middle ear.

INTRODUCTION: Glial heterotopia is defined as the presence of normal glial tissue in an abnormal site. CASE REPORT: We report the case of a 63-year-old man who presented with right hearing loss and tinnitus. ENT examination, computed tomography and magnetic resonance imaging showed signs of chronic otitis media. Right mastoidectomy demonstrated a solid mass of the right mastoid and middle ear with no associated dehiscence of the tegmen tympani. Histological examination of the mass revealed normal glial tissue. DISCUSSION: Glial heterotopia is a rare entity, which must be distinguished from encephalocele. It is usually an incidental surgical finding when the surgeon observes a mass of the mastoid and middle ear not communicating with the central nervous system. Histological examination confirms the diagnosis by revealing normal glial tissue in the ear.