Acoustic immittance testing may also be completed at the time you undergo basic hearing testing. Acoustic immittance testing evaluates the eardrum and the middle ear space behind the eardrum, as well as a muscle reflex that involves the eardrum and middle ear, the inner ear, the auditory nerve, the auditory brainstem pathways and the facial nerve. Acoustic immittance testing helps to localize what part of the ear may be involved in hearing loss.
During the test, a small plastic probe is placed in one or both ear canals. During eardrum testing, also calledtympanometry, a slight pressure is placed on the eardrum to determine how well the eardrum vibrates and how much air is behind the eardrum. The test is generally not uncomfortable and it is very brief.
Acoustic reflex testing may also be performed. During acoustic reflex testing loud tones are presented to each ear individually. The tones are also brief, usually not uncomfortable, and will not damage your hearing.
Once reflex threshold testing is completed, one or two longer, louder tones may be presented to each ear. The long, loud tones provide information regarding the status of the hearing nerves.