Evaluation of Universal Newborn Hearing Screening with Transient-Evoked Otoacoustic Emission and Auditory Brainstem Response: A Cross-Sectional Study with the Literature Review

Hearing impairment (HI) is one of the most common congenital disorders in neonates and is considered as a severe and obscure handicap. The best early diagnostic method for HI in newborns is universal newborn hearing screening (UNHS). This method has been implemented since a few years ago in Iran. In this study، we introduced the findings of hearing screening in a hospital in Tehran (Iran). This cross-sectional study was conducted on all newborns (n = 3818) in Najmieh Hospital (Tehran، Iran) during 2006-07. Newborns were screened using the Transient­-Evoked Otoacoustic Emission (TEOAE) test at the first 48 hours after birth. The results were documented as «pass» (desirable) or «refer» (undesirable). Neonates with undesirable results were re-screened during the next 2-4 weeks. If the responses in both sessions (test and retest) were not desirable، the infants were referred for a final diagnosis with Auditory Brainstem Response (ABR) test before three months of age. They were then referred to an otolaryngologist for more evaluations. From 3818 neonates screened، 90% had a pass response and 10% were referred for retest at 2-4 months of age. Of those who were referred، only 11 (3. 6%) infants had an undesirable response again. Among these، nine infants referred for ABR and only 3 subjects showed sensory-neural hearing loss as the final diagnosis. One of them did not have any risk factors of HI. In order to minimize false negative and positive results، suspected cases are suggested to be reevaluated during the 2nd to 4th weeks after birth. In addition، high risk infants should be tested by ABR. Since one third of the children with HI in this study did not have any risk factors for HI، we recommend careful hearing screening for all neonates even those without any risk factors.