Hearing screening tests provide a quick and cost effective way to separate people into two groups: a pass group and a fail group. Those in the pass group are presumed to have no hearing loss. Those who fail are in need of an in-depth evaluation by an audiologist and may also need follow-up care from other professionals.
Hearing screening occurs from birth throughout the adult years when requested, when conditions occur that increase risk for hearing loss, or when mandated by state and local laws or practices.
It is recommended that all hearing screening programs be conducted under the supervision of an audiologist holding the American Speech-Language-Hearing Association’s (ASHA) Certificate of Clinical Competence (CCC).
Newborns and Infants
Hearing screening for newborns before they leave the hospital or maternity center is becoming a common practice. Without such programs, average age of detection of significant hearing loss is approximately 14 months. [Task Force on Newborn and Infant Hearing. (1999, February). Newborn and infant hearing loss: Detection and intervention. Pediatrics, 103 (2): 527-530.)].
When hearing loss is detected late, language development is already delayed. Children are more likely to perform below their grade level, and are more likely to be held back, drop out of school, and fail to earn a high school diploma. These consequences are in sharp contrast to those for children who are identified early, receive early intervention, and then are found to function at the level of their peers by the time they enter school.
Screening procedures for newborns and infants can detect permanent or fluctuating, bilateral or unilateral, and sensory or conductive hearing loss, averaging 30 to 40 dB or more in the frequency region important for speech recognition (approximately 500-4000 Hz).
The screening of newborns and infants involves use of non-invasive, objective physiologic measures that include otoacoustic emissions (OAEs) and/or auditory brainstem response (ABR). Both procedures can be done painlessly while the infant is resting quietly.
Otoacoustic emissions are inaudible sounds from the cochlea when audible sound stimulates the cochlea. The outer hair cells of the cochlea vibrate, and the vibration produces an inaudible sound that echoes back into the middle ear. This sound can be measured with a small probe inserted into the ear canal. Persons with normal hearing produce emissions. Those with hearing loss greater than 25-30 dB do not. OAEs can detect blockage in the outer ear canal, middle ear fluid, and damage to the outer hair cells in the cochlea.
Auditory brainstem response is an auditory evoked potential that originates from the auditory nerve. It is often used with babies. Electrodes are placed on the head, and brain wave activity in response to sound is recorded. ABR can detect damage to the cochlea, the auditory nerve and the auditory pathways in the stem of the brain.
ASHA-certified audiologists (and state licensed where applicable) should be designated as the manager of these screening programs.
What happens if an infant does not pass the screening?
Infants who do not pass a screening are often given a second screening to confirm findings and then referred for follow-up audiological and medical evaluations that should occur no later than 3 months of age. These evaluations confirm the presence of hearing loss; determine the type, nature, and (whenever possible) the cause of the hearing loss; and help identify options for treatment.
Even if the infant passes screening, certain conditions do not produce immediate hearing loss. Rather, the hearing loss occurs later in the child’s development.
An infant with any of the following indicators for progressive or delayed-onset hearing loss should receive audiologic monitoring every six months until age 3 years :
- Parental or caregiver concern regarding hearing, speech, language, and/or developmental delay
- Family history of permanent childhood hearing loss
- Characteristics or other findings associated with a syndrome known to include a sensorineural and/or conductive hearing loss
- Postnatal infections associated with sensorineural hearing loss including bacterial meningitis
- In utero infections such as cytomegalovirus, herpes, rubella, syphilis, and toxoplasmosis
- Neonatal indicators-specifically hyperbilirubinemia at a serum level requiring exchange transfusion, persistent pulmonary hypertension of the newborn associated with mechanical ventilation, and conditions requiring the use of extracorporeal membrane oxygenation (ECMO)
- Syndromes associated with progressive hearing loss such as neurofibromatosis, osteopetrosis, and Usher’ s syndrome
- Neurodegenerative disorders, such as Hunter’s syndrome, or sensory motor neuropathies, such as Friedreich’s ataxia and Charcot-Marie-Tooth syndrome
- Head trauma
- Recurrent or persistent otitis media with effusion for at least 3 months
The Individuals with Disabilities Education Act (IDEA) in its regulations requires states to develop and implement a statewide system of early intervention services for infants and toddlers. It is required that infants and toddlers with disabilities be identified and evaluated using at risk criteria and appropriate audiologic screening techniques. After a hearing loss is confirmed, coordination of services should be facilitated by the infant’ s medical manager and the IDEA coordinating agencies.
Contact your local school district or your state or local health department to find out how to obtain screenings/evaluations and intervention services through your state’s Early Intervention program.Sharing is Caring!