Adapted and updated from Gottlieb MI: Otitis media. In Levine MD, Carey WB, Crocker AC, et al, editors: Developmental-Behavioral Pediatrics, Philadelphia, 1983, WB Saunders. ASA, Acoustical Society of America.
and sensorineural loss caused by cochlear disease. Any hear-identifying hearing-impaired children. Universal screening of ing loss may have a significant effect on the child’s developing newborns is required prior to nursery discharge and includes communication skills. These skills then affect all areas of the the following: child’s cognitive and skills development (Table 10-8). • Auditory brainstem response (ABR) measures how
It is sometimes quite difficult to accurately determine the the brain responds to sound. Clicks or tones are played presence of hearing in infants and young children. Inquir-through soft earphones into the infant’s ears. Three ing about a newborn’s or infant’s response to sounds or even electrodes placed on the infant’s head measure the brain’s observing the response to sounds in the office is unreliable for response.
• Otoacoustic emissions measure sound waves produced in the inner ear. A tiny probe is placed just inside the infant’s ear canal. It measures the response (echo) when clicks or tones are played into the infant’s ears.
Both of these tests are quick (5 to 10 minutes), painless, and may be performed while the infant is sleeping or lying still. The tests are sensitive but not as specific as more definitive tests. Infants who do not pass these tests are referred for more comprehensive testing. Many of these infants have normal hearing on definitive testing. Infants who do not have normal hearing should be immediately evaluated or referred for etiologic diagnosis and early intervention.
For children not screened at birth (such as children of immigrant parents) or children with suspected acquired hearing loss, later testing may allow early appropriate intervention. Hearing can be screened by means of an office audiogram, but other techniques are needed (ABR, behavior audiology) for young, neurologically immature or impaired, and behaviorally difficult children. The typical audiologic assessment includes pure-tone audiometry over a variety of sound frequencies (pitches), especially over the range of frequencies in which most speech occurs. Pneumatic otoscopic examination and tympanometry are used to assess middle ear function and the tympanic membrane compliance for pathology in the middle ear, such as fluid, ossicular dysfunction, and eustachian tube dysfunction (see Chapter 9).
The treatment of conductive hearing loss (largely due tootitis media and middle ear effusions) is discussed in Chapter 105. Treatment of sensorineural hearing impairment may bemedical or surgical. If amplification is indicated, hearing aidscan be tuned preferentially to amplify the frequency ranges inwhich the patient has decreased acuity. Educational intervention typically includes speech-language therapy and teachingAmerican Sign Language. Even with amplification, many hear-ing-impaired children show deficits in processing auditoryinformation, requiring special educational services for helpingto read and for other academic skills. Cochlear implants are surgically implantable devices that provide hearing sensation toindividuals with severe to profound hearing loss. The implantsare designed to substitute for the function of the middle ear,cochlear mechanical motion, and sensory cells, transformingsound energy into electrical energy that initiates impulses inthe auditory nerve. Cochlear implants are indicated for children older than 12 months with profound bilateral sensorineural hearing loss who have limited benefit from hearing aids,have failed to progress in auditory skill development, and haveno radiologic or medical contraindications. Implantation inchildren as young as possible gives them the most advantageous auditory environment for speech-language learning.