Tympanometry

Also known as impedance audiometry, the test measures how readily the middle ear system (the tympanic membrane and the middle ear ossicles) can be set into vibration with a change of air pressure in the external auditory canal (EAC). In the normal ear, maximum sound transmission occurs when the air pressure within the middle ear space is the same as atmospheric pressure, i.e. equal to the air pressure in the EAC.