The ear is divided into the external, middle, and inner parts. The external ear is comprised of the auricle, the external auditory canal, and the external auditory meatus. The middle ear contains an air space and mastoid cells ventilated by the eustachian tube, the tympanic membrane, and the three ossicles. The inner ear is comprised of the cochlea, semicircular canals, fluids, and cranial verve VIII. The facial nerve courses through the middle ear space and mastoid process. It can be affected by a severe infection in these areas. Facial asymmetry during an acute ear infection is an indication of an unusually severe infection.