Conditions of the external ear, middle ear, inner ear and mastoid process, following ICD-10 Chapter VIII (Diseases of the Ear and Mastoid Process). Belongs here: a degenerative, inflammatory or structural disease of the ear or mastoid process itself, such as otitis media, otosclerosis, mastoiditis or Meniere's disease, and a hearing or balance disorder with no external or systemic cause identified. Does not belong here: an ear finding that is one manifestation of a systemic disease classified primarily elsewhere, such as diabetes-related hearing loss, which stays with the metabolic disease that causes it, or a balance disorder rooted in a structural brain lesion, grouped under diseases of the nervous system.