Automated auditory brainstem response in neonatal hearing screening

Severe congenital hearing impairment is an important handicap affecting 0.1% of apparently healthy liveborn infants and 1-2% of graduates of neonatal intensive care units. The prognosis for intellectual, emotional, language and speech development in the hearing-impaired child is improved when the diagnosis is made early and intervention is begun before the age of 6 mo. Universal screening is preferable, since about 50% of infants with hearing loss are not discovered if neonatal hearing screening is restricted to high-risk groups. The automated auditory brainstem response (AABR) screener is a dedicated hearing screening device which provides information not only about the outer/middle ear and cochlea but also about the auditory pathway up to the brainstem. AABR has an agreement with conventional auditory brainstem response up to 98%. It uses a 35 dB near hearing level click. No operator interpretation is needed and it can be used on the ward and during oxygen therapy without disturbance from ambient noise. Reported referral rates in a hospital-based screening programme at the time of discharge vary, with an average of 4%. AABR has also been used in a home-based setting, with the same results. The time necessary for screening varies with the setting, but ranges from 4 to 15 min. Initial costs range from $15 to $25 per test, which is similar to neonatal screening for metabolic diseases. In addition to individual healthcare savings, early diagnosis may lead to savings on costs of intensive speech-language intervention and educational facilities.