What is an otoacoustic test for hearing loss?

Otoacoustic emissions test assesses whether the hair cells of the cochlea, in the inner ear, are functioning. Normally, hair cells emit sound in response to incoming sounds. Otoacoustic testing detects the hair cell sound with a rubber-tipped probe inserted into the ear canal. The procedure usually takes less than five minutes for each ear. The absence of sound from the hair cells can mean either a problem with the cochlea or mild conductive hearing loss. The test is used, sometimes in combination with the evoked potential test, to screen babies before they leave the hospital and has significantly lowered the age of identification of hearing loss. The otoacoustic test is also used in young children and is becoming increasingly common for adults with sensorineural or permanent hearing loss caused by damage to the cochlea, hair cells, or auditory nerve or tinnitus (ringing in ears), or who are taking medications that can damage the ear.