OTO Acoustic Emission: OAEs are low intensity sounds/acoustic signal that are generated by the cochlea and propagate through the middle ear into the ear canal where they are recorded.
- OAEs are probably not essential to hearing, but rather are by-product of active processing by the outer hair cells system.
- They are the most probably generated by active mechanical contraction of the outer hair cells, spontaneously or in response to sounds.
- OAEs revel, with considerable sensitivity, the integrity of outer-hair cell function.
- It is a non-Invasive,help to assess the activity of cochlea, test is mostly used for new born hearing screening.
- There are basically three types of OAE are: (a) Spontaneous (b)Transient evoked (c) distortion Products.
LIMITATIONS: OAE can’t get distinguish between conductive hearing loss & sensorineural hearing loss.
What is OAE?
Ans: An Otoacoustic emission (OAE) is an acoustic signal generated mainly within cochlear outer hair cells (OHC)that shows their functioning.
There are two types of otoacoustic emissions: Transient evoked otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) which are widely used in hearing screening. For TEOAE acquisition a series of wideband clicks is used as a stimulus. For DPOAE acquisition the receptors are stimulated by a pair of pure tones at frequencies f1 and f2. The resulting emission is the distortion product tone at the frequency 2f1- f2.
What do otoacoustic Emission Results Tell Us?
Ans: OAE test is used as a screening method in newborns and infants. The PASS result means that OAE has been recorded and outer hair cells are not damaged. Patients who fail to generate OAE should be re-screened and/or reffered for additional audiological testing.