Pediatric Hearing Testing
Hearing is a crucial part of any child’s development, especially in the first few years of life. Even a mild or partial hearing loss can affect a child’s proper speech and language development. Fortunately, many hearing issues in children can be overcome if hearing loss is caught early and monitored regularly.
When should your child’s hearing be evaluated?
Newborn hearing screenings are standard in hospitals nationwide, and your child’s hearing should be screened before he or she leaves the hospital or birthing center. Two main objectives of a newborn hearing screening are to identify newborns who are likely to have hearing loss and require further evaluation and to identify newborns with medical conditions that may cause late-onset hearing loss. According to the American Academy of Pediatrics Early Hearing Detection and Intervention guidelines, hearing screening should occur by 1 month of age, diagnosis of any hearing loss by 3 months of age, and treatment with early intervention services by 6 months of age. Hearing screenings are meant to target children with permanent hearing loss. However, different protocols and screening tests are more effective at identifying and classifying hearing loss. Furthermore, passing a screening does not indicate normal hearing across the full frequency range so therefore, it is essential to monitor your child’s hearing, speech, and language development throughout childhood. If your child seems to have trouble hearing, demonstrates abnormal speech development, or if your child’s speech is difficult to understand, their hearing should be tested. Other risk indicators associated with permanent congenital, delayed-onset, and/or progressive hearing loss in childhood include:
Family history of permanent childhood hearing loss
Neonatal intensive care of more than 5 days or any of the following regardless of length of stay: ECMO, assisted ventilation, exposure to ototoxic medications (gentamicin and tobramycin) or loop diuretics (furosemide/Lasix), and hyperbilirubinemia that requires exchange transfusion
In utero infections such as CMV, herpes, rubella, syphilis, and toxoplasmosis
Craniofacial anomalies, including those that involve the external ear, ear canal, ear tags, ear pits, and temporal bones
Physical findings, such as white forelock, that are associated with a syndrome known to include a hearing loss
Syndromes associated with hearing loss or progressive or late-onset hearing loss such as neurofibromatosis, Usher syndrome, Waardenburg syndrome, Alport syndrome and Pendred syndrome
Neurodegenerative disorders such as Hunter syndrome, or sensory-motor neuropathies such as Friedreich ataxia and Charcot-Marie-Tooth syndrome
Postnatal infections associated with hearing loss including confirmed bacterial and viral meningitis
Head trauma that requires hospitalization
Chemotherapy
Recurrent or persistent middle ear infections for at least 3 months
Other than these risk factors, parents should be aware of certain hearing milestones that most children reach in the first year of life including:
Startling or jumping to sudden loud noises
Recognizing a parent’s voice by 3 months
Turning his/her eyes or head toward a sound by 6 months
Imitate some sounds and produces one or two words by 12 months
As your child continues to grow and develop, signs of hearing loss may include:
Limited, poor, or no speech
Frequent inattentiveness
Difficulty learning
Needing higher television/music volume
Failing to respond to conversation-level speech or answering questions inappropriately
Failing to respond to his/her name or becoming easily frustrated in a lot of background noise
How is hearing tested?
Depending on your child’s age, development, and health there are several methods used to test hearing. For children of all ages and for infants who cannot demonstrate behavioral responses, certain objective testing should be performed. Objective testing used for newborn hearing screenings include otoacoustic emissions testing and/or the auditory brainstem response.
Otoacoustic emissions (OAEs) tests the inner ear’s response to sound at certain pitches without a behavioral response. During this test, a soft insert is placed in the child’s ear. It plays sounds and measures an “echo” response that occurs in ears with normal hearing
Auditory brainstem response (ABR) tests the auditory nerve’s pathway that carries sound from the ear to the brain. During this test, the child wears soft inserts in their ears and adhesive electrodes placed on their head. Sounds are played in order to test the pathway and measured
through the electrodes.
Hearing tests conducted at an ENT or audiologist’s office are typically performed in a sound treated booth and may involve a number of assessments including visual examination of the external and middle ear, tympanometry testing, OAEs, and behavioral testing if able.
Tympanometry testing is a measure of change in the middle ear pressure by way of the eardrum. This test involves placing a probe in the child’s ear canal and measuring the pressure which could indicate normal middle ear pressure, fluid behind the eardrum, or a perforation in the eardrum.
Following objective testing, behavioral testing may be performed depending on the child’s abilities in order to determine the child’s hearing performance based on their own responses.
For children around 6 months-2.5 years: Visual response audiometry is used to measure a child’s response to stimuli by either eye or head movement. The child is conditioned to associate the specific stimuli with a reinforcer, such as a lighted toy.
For children 2.5-4 years: Conditioned play audiometry is used to assess a child’s response to speech and specific pitches or frequencies. The child is conditioned to respond when a stimulus is heard, such as dropping a block in a bucket or placing a peg in a pegboard.
For typically developing children around 5 years of age and older, a conventional hearing test similar to what adults experience can be performed.
What to do with the results of your child’s hearing test?
Hearing tests that reveal normal results do not negate future evaluations. Hearing loss can occur at any time of life, and some inherited forms of hearing loss do not appear until a child is older. Additionally, illnesses, ear infections, injuries, certain medications, and loud noise exposure are all potential hearing loss causes in children. It is important to monitor your child’s development and have their hearing assessed if any concerns arise.
If your child’s hearing tests results show abnormal findings, it is crucial to follow up with a pediatric audiologist and ENT to determine the possible causes of the hearing loss and treatment recommendations. Audiologic assessment and intervention is an ongoing process, and children with hearing loss require regular monitoring to evaluate fluctuating or progressive hearing loss, as well as any developmental or behavioral issues.
If you have any concerns about your child’s hearing, do not hesitate to contact one of our many locations to set up a hearing evaluation.
References:
American Academy of Pediatrics. (2017). Early Hearing Detection and Intervention (EHDI). Retrieved from https://www.aap.org/enus/advocacyandpolicy/aaphealthinitiatives/PEHDIC/pages/early-hearing-detection-and-intervention.aspx
American Academy of Pediatrics, Joint Committee on Infant Hearing. Year 2007 position statement: principles and guidelines for early hearing detection and intervention programs.Pediatrics.2007;120 (4):898– 921
Clayton, E. W. (1992). Issues in state newborn screening programs. Pediatrics, 90, 641-646.
Harlor, Jr., A. D. B., & Bower, C. (2009). Hearing assessment in infants and children: Recommendations beyond neonatal screening. Pediatrics, 124, 1252-1263.
Morlet, T. (Ed.). (2016, March). Hearing Evaluation in Children (for Parents). Retrieved from https://kidshealth.org/en/parents/hear.html
Yoshinaga-Itano, C., DeConde Johnson, C., Carpenter, K., & Stredler Brown, A. (2008). Outcomes of children with mild bilateral hearing loss and unilateral hearing loss. Seminars in Hearing, 29, 96-211.