Otoacoustic Emission (OAE) Instrument - Eroscan

Otoacoustic Emission Test Equipment Maico Eroscan OAE instrument

OAEs provide a simple, efficient and non-invasive objective indicator of healthy cochlear function and OAE screening is widely used in universal new-born hearing screening programmes.

Hearing loss is one of the most cases of birth defects possible.
OAE's can be evoked by clicks (TEOAE) or as distortion products of two sinusoidal tones (DPOAE).
TEOAE = Transient evoked OAE
DPOAE = Distortion product OAE

OAE's indicate the functionality of the outer hair cells of the cochlea
Highly correlated to normal hearing

A very sensitive microphone is necessary to measure OAE's.

Distortion Product DPOAEs:

Distortion Product Otoacoustic Emissions (DPOAEs) are acoustic signals that can be detected in the ear canal of a person with normal outer hair cell function, subsequent to stimulation of the auditory system with a pair of pure tones at frequencies f1 and f2.

Transient Evoked TEOAE:

Transient Evoked Otoacoustic Emissions (TEOAEs) are acoustic signals that can be detected in the ear canal of a person with normal outer hair cell function, subsequent to stimulation of the auditory system with a series of wideband Clicks.

Result:

Most equipments available offer following results:

  • PASS
  • REFER
  • NOISY
  • No Seal
  • Pass criteria can be defined, such as number of frequencies to PASS, minimum value of OAE and averaging time

    Role of OAEs:

    OAEs provide a simple, efficient and non-invasive objective indicator of healthy cochlear function and OAE screening is widely used in universal new-born hearing screening programmes.
    Hearing loss is one of the most cases of birth defects possible.

    OAE challenges:

    Condition of baby.

  • Baby should be calm or sleeping.
  • Screener should have a some training and subsequent experience to ensure little number of REFER-rates
  • OAE Pros and Cons:

    Advantage:

  • fast result.
  • cost of equipment
  • Disadvantage:

  • High REFER rate due to fluid in ear early after birth.
  • Missing of any retro-cochlea damage such as AN.