Learn more about otoacoustic emission and their significance in ENT teaching, as well as the different types of tests that are differentiated and how the examination plays a role in young children and babies. If you believe your hearing is limited, take advantage of Amplifon's free testing services by visiting one of our clinics near you.
The low-intensity sound signals emitted from the cochlea were first noticed in the 1940s, but they were first measured in the late 1970s, when microphones that could detect sound signals of a correspondingly low intensity were invented. Otoacoustic emissions are low-intensity sound signals emitted from the cochlea spontaneously or in response to an acoustic stimulus.
The presence of otoacoustic emissions (OAE) in the ear contributes to an understanding of several aspects concerning the state of hearing. First of all, OAEs indicate that the transmission of sound transmission in the ear is working properly. Secondly, they verify that the hair cells are functioning normally, which confirms the correct sensitivity of hearing.
Otoacoustic emissions (OAEs) can be used to diagnose hearing loss due to sensorineural damage because they originate in the cochlea. OAE tests also identify disorders that interfere with sound traveling along the path from your ear drums to your inner ears.
Otoacoustic emissions are produced by the cochlea without any acoustic stimulation from the environment. These tests are mainly used for patients who can't actively participate in the test, because they may be unconscious or uncooperative. The advantage of these emissions is that they provide an objective result.
Otoacoustic emissions tests are most common among pediatric patients, due to their convenience and lack of invasive measures. These exams can provide instant and reliable feedback about the child's cochlea health, which is helpful in making informed decisions.
These emissions are triggered by acoustic stimuli. There are a variety of factors that can influence the emission of sound, and these responses can be classified based on their characteristics.
Transitory otoacoustic emissions (TEOAEs): These sounds are produced by a brief stimulus, such as a click. They're commonly used to detect ear damage and diagnose hearing loss early on.
Stimulus-frequency otoacoustic emissions: These signals originate within the cochlea at the same frequency as the evoking tone, and are emitted in response to a continuous stimulus. They're different than other OAEs, which aren't typically used in clinical practice.
Distorsively produced otoacustic emissions (DPOAE): These emissions are created as a reaction to two tones being played at the same time, but at different frequencies. These otoacoustic emissions are very important in a clinical setting, as they make it possible to detect even mild damage to the cochlea that may not show up in a standard hearing test.
If an ear does not pass the first OAE test, a second test will be conducted within two weeks.
If the result of the second OAE test is also "refer," the child must be evaluated by a specialist. The specialist will assess if there is an issue with the outer or middle ear (such as a blockage, fluid buildup, or structural abnormalities) that is affecting the accuracy of the OAE screening. If necessary, the ear will require treatment or ongoing monitoring.
If the doctor determines that there is nothing obstructing proper screening, a further hearing test will be performed to assess the child's hearing ability. If possible, a pediatric audiologist will also deepen the clinical diagnosis.