Pediatric Testing
These tests are performed in a sound proof room, called a sound booth. The goal of a pediatric hearing test is to obtain information regarding hearing levels from children who are unable to respond in the same manner that older children and adults respond. This is done in one of two ways depending on the age of the child. For infants and young toddlers, aged 5 months to about 2.5 years of age, Visual Reinforcement Audiometry (VRA) is used. Conditioned Play Audiometry (CPA) is used for children aged 2.5 – 4 years old.
How is it performed?
Visual Reinforcement Audiometry (VRA): During VRA testing the child is seated on the parent’s lap, in a high chair or seated alone. The child must be able to sit upright and turn their head from side to side. A test assistant is seated facing the child to keep their attention forward between auditory stimuli. VRA uses lighted and/or animated toys that are flashed on simultaneously with the presentation of an auditory signal (warble tones, narrow band noise or speech) during a conditioning period.
Once the child is conditioned, the toy is activated immediately after the child turns toward the signal. The auditory signal is presented either through speakers on the right or left side (sound field) or, if the child will accept them, through foam insert earphones. The softest level that the child responds to the auditory signal is recorded on the audiogram. Sound field testing provides information about the hearing level of only the better ear while insert earphone testing provides information about the hearing levels of each ear.
CPA: During Conditioned Play Audiometry the child is seated across from a test assistant and is instructed to place a toy in a bucket or game when a sound is heard either through insert ear phones or a sound speaker. Initial sounds are presented well above the child?s expected threshold to familiarize the child with the task. Once the child is conditioned and understands the task, progressively softer sounds are presented until the child?s threshold is found.
Depending on the age of the child and their willingness to repeat words, a speech reception threshold (SRT) or speech awareness threshold (SAT) may be obtained. A SRT is the softest level at which the child can understand speech. The child may be asked to point to body parts, objects or pictures or to repeat two syllable words to obtain an SRT. The SAT is the softest level of speech that the child can hear. The SAT may be obtained by having the child respond to soft speech in the same way they respond to the tones for either conditioned play or VRA.
How long does it take?
These appointments are scheduled for 45 minutes. In addition to VRA or CPA additional testing may be performed during this appointment, such as Immittance tests and otoacoustic emissions.
Important instructions
Since this test requires the child?s participation, it is best scheduled around naptime. Pick a time when you know your child is most attentive during the day. This may be after naptime or first thing in the morning.
Immittance Tests
This group of tests (tympanometry and acoustic reflexes) measure how well your child?s middle ear works. These tests are commonly performed as they are sensitive to middle ear disorders. These tests do not require the child to respond.
Tympanometry: An ear tip is placed in the canal that is connected to a machine that briefly varies the pressure in your child?s ear. Results from this test could indicate:
- fluid in the middle ear (otitis media)
- discontinuity of the ossicular chain (the three bones in the middle ear)
- perforated eardrum
- Eustachian tube dysfunction
Acoustic Reflex Thresholds
This test measures how much the stapedius muscle in the middle ear contracts in response to a loud sound. This muscle acts as a protective mechanism that dampens loud sounds before they reach the cochlear (hearing organ). Absence or presence of acoustic reflexes for various presentations may be important in the differential diagnosis of both peripheral and central disorders of the auditory system such as vestibular schwannoma or facial nerve disorders.
Otoacoustic Emissions
What is it
This test measures how well your child?s cochlea, or inner ear works. The outer hair cells of the inner ear (cochlea) produce low level, inaudible sounds, called Otoacoustic emissions (OAE?s). OAE?s can either occur spontaneously or in response to clicks or tones. When the hair cells of the inner ear are stimulated, they respond by sending information to the brain and by sending an “echo”back to the outer ear. This “echo”is analyzed and recorded by the audiologist. OAE?s are usually present in individuals with a normal functioning cochlea but may be absent if even a mild conductive or cochlear hearing loss exists.
How it is performed
This test requires the child and everyone in the room to be very quiet for the measurement to be obtained. Your child will hear soft sounds played through a small ear phone. The response from the ear will be measured by a hand-held computer. This test only takes a few minutes to complete.
ABR
What is it?
The Auditory Brainstem Response (ABR) is a test used to determine hearing loss in children who are either too young to respond or are unable to respond. It tells us how loud a sound must be for your child to hear it. What it does not do is tell us is if your child understands what he or she hears. An ABR is performed while your baby sleeps. This test can be performed under sedation or during natural sleep.
How is it performed?
The audiologist will scrub the skin where four electrodes will be placed (forehead and behind the ears). After the electrodes are in place, you may hold your child until he or she falls asleep. Once your child is sleeping, the audiologist will place small ear phones into his or her ears that will make a clicking sound. This sound travels from your child?s ears to the brain (through the auditory pathway) where it is recorded through the electrodes.
You will know the results of the ABR on the same day as the testing. Your audiologist will explain the results as well as recommend follow up appointments, if needed and send her report to your ENT.
How long does it take?
Under natural sleep, your child will be scheduled for two hours for the ABR to be completed. Your audiologist may complete additional tests at this appointment, such as Immittance tests and otoacoustic emissions (links).
Why should my child have a hearing test?
On January 1, 2008, California implemented the Universal Newborn Hearing Screening Legislation, which requires hospitals to provide hearing screenings to every newborn. If the baby does not pass the newborn hearing screening, he or she will be referred for further testing with a pediatric audiologist. All of our audiologists have received extensive training in pediatrics and are state-licensed and nationally certified. They perform these tests to determine if the baby has a hearing loss and if so, what degree (how much hearing loss) and type (what part of the auditory system is affected).
The younger a child is diagnosed with hearing loss and fit with amplification (hearing aids / cochlear implants) the better chances he or she has to learn language. Studies have shown that children that are amplified by 6 months of age can learn language similarly to their normal hearing peers.
Our goals for your child include:
- Providing appropriate amplification by the age of 3 months of age
- To see the child enrolled in early intervention programs before 6 months of age