Age of Child

Test

Comments

All ages

Evoked otoacoustic emission (OAE)

Screen for middle and inner ear abnormalities contributing to diminished hearing.

Measure acoustic emissions generated in the cochlea in response to sounds. These emissions are picked up by sensitive microphones placed in the outer ear canal.

These tests identify cochlear activity in each ear separately. Probes are placed in each ear canal, signals are delivered, and otoacoustic response (presence, absence, intensity) is recorded. The test does not measure transmission of sounds to the brain.

Residual vernix in the ear or mild MEE can interfere with the recording of the OAEs, creating a false-positive result.

Diagnostic auditory brainstem response (ABR)

Detects brain activity and quantifies the characteristics of the response when sounds are presented. May be used as part of newborn screening program.

Earphones are placed on the child for introduction of clicking sounds. Electrodes are placed on the child’s head to detect brain activity when sounds are heard. A computer averages these responses and displays waveforms.

There are characteristic waveforms for normal hearing in portions of the speech range. If brain activity is identified, test result is a “Pass.” A normal ABR can predict fairly well that a child’s hearing is normal in that part of the range. Characteristics of the response are measured and quantified by the audiologist.

An abnormal ABR may be the result of hearing loss, but it may also be the result of some medical problems or measurement difficulties.

Tympanometry

Assesses the status of the middle ear conduction system—that is, the tympanic membrane and the mobility of the bones of the middle ear.

A tone is introduced into the ear canal and the amount of sound reflected back from the tympanic membrane is measured as the pressure changes during the test.

The resulting graph should show a clear peak in the center as the mobile tympanic membrane moves in response to the sound.

An ear with effusion (fluid behind the membrane) will show little, if any, mobility of the tympanic membrane.

Birth to 9 months

Automated auditory brain response

See above

9 months-2.5 years

Visual reinforcement audiometry (VRA)

Measures response of child to speech and frequency-specific stimuli that are transmitted via speakers or earphones. With the VRA, when the child turns to the sound stimulus, a puppet lights up to reward/reinforce the child’s listening behavior.

2.5 years-4 years

Play audiometry

Evaluates hearing in each ear separately and evaluates behavioral responses to the sounds. After training and practice, earphones are placed on the child and sounds of specific frequencies and decibels are introduced. Child’s behavior in response to sounds is recorded.

No response to sounds or inconsistent response to sounds indicates hearing loss.

4 years-adolescent

Play or puretone audiometry

Puretone screening allows office screening for hearing loss for children aged 4 years and older.

In a quiet room, child is asked to indicate when a sound is heard. Various tones are presented by the instrument.