Tympanometry examination. Teenage girl having tympanometry to measure the movement of the eardrum (tympanic membrane) and assess the condition of the middle ear. A probe with an earplug (green) is inserted into the ear. A sound is emitted from the probe and, whilst the pressure in the ear canal is varied, the amount of sound reflected by the eardrum is recorded. The results are displayed on a tympanogram (not seen) which is interpreted by an audiologist. Tympanometry aids the diagnosis of glue ear (middle ear inflammation due to blockage of the Eustachian tube), which commonly affects hearing in children.