Otoacoustic Emission (OAE)
In the middle ear, within the cochlea — one of the three small bones responsible for hearing — low-frequency acoustic signals are produced.
This phenomenon is called otoacoustic emission (OAE).
It is a method of measuring these low-frequency sounds generated in the cochlea using a sensitive microphone.
The test is painless and performed while the patient is seated, with a small earplug-shaped microphone placed in the outer ear.
During the test, the patient should remain still and silent.
If there is earwax or blockage in the outer ear, the test cannot be performed.
Middle ear inflammation, trauma, tympanic membrane retraction, infection, or negative pressure in the middle ear also prevent the test from being carried out.
The OAE test is performed in two types:
• Spontaneous Otoacoustic Emission (Spontaneous OAE)
• Evoked Otoacoustic Emission (Evoked OAE)
Spontaneous OAE refers to weak, continuous signals that occur without any external stimulus.
They are found in about 50% of people with normal hearing.
Since spontaneous emissions can appear even in normal conditions, this type of test is rarely used in clinical practice.
Evoked OAE measures the ear’s response to short, low-frequency sound waves (lasting about 4–20 milliseconds).
Clinical applications:
• Newborn hearing screening
• Acoustic trauma
• After auditory nerve surgery
• Functional (non-organic) hearing loss
Because no anesthesia is required and the procedure is very short, this test is considered a convenient and efficient diagnostic method.
This phenomenon is called otoacoustic emission (OAE).
It is a method of measuring these low-frequency sounds generated in the cochlea using a sensitive microphone.
The test is painless and performed while the patient is seated, with a small earplug-shaped microphone placed in the outer ear.
During the test, the patient should remain still and silent.
If there is earwax or blockage in the outer ear, the test cannot be performed.
Middle ear inflammation, trauma, tympanic membrane retraction, infection, or negative pressure in the middle ear also prevent the test from being carried out.
The OAE test is performed in two types:
• Spontaneous Otoacoustic Emission (Spontaneous OAE)
• Evoked Otoacoustic Emission (Evoked OAE)
Spontaneous OAE refers to weak, continuous signals that occur without any external stimulus.
They are found in about 50% of people with normal hearing.
Since spontaneous emissions can appear even in normal conditions, this type of test is rarely used in clinical practice.
Evoked OAE measures the ear’s response to short, low-frequency sound waves (lasting about 4–20 milliseconds).
Clinical applications:
• Newborn hearing screening
• Acoustic trauma
• After auditory nerve surgery
• Functional (non-organic) hearing loss
Because no anesthesia is required and the procedure is very short, this test is considered a convenient and efficient diagnostic method.