Clinical Follow-up of Hearing-Impaired Infants Detected by Newborn Hearing Screening

Abstract

BACKGROUND AND OBJECTIVES: When screened using cord blood, congenital hearing loss are detected more frequently than other congenital metabolic diseases such as phenylketonuria or congenital hypothyroidism. Newborn hearing screening is important because the early identification and intervention of neonatal hearing loss is beneficial for the language development. We aimed to analyze clinical characteristics including associated diseases and present hearing state, and the effects of speech rehabilitation in the hearing-impaired infants detected by newborn hearing screening program of Ajou University Hospital. SUBJECTS AND METHOD: Seventy nine hundred twelve neonates (6915 well babies and 997 NICU babies) were screened by transient evoked otoacoustic emission (TEOAE) and auditory brainstem response (ABR). Medical records of infants with bilateral hearing loss of more than 60 dB were evaluated, and they were further studied with temporal bone CT scan and follow-up hearing tests using ABR. The exon2 of the connexin26 gene was sequenced to detect the mutation. RESULTS: Fourteen of 7912 infants initially had bilateral hearing loss of more than 60 dB. Associated diseases were prematurity, hyperbilirubinemia, sepsis, low birth weight, chromosomal anomaly, cleft palate, congenital nevus, and congenital aural atresia. Three of 14 infants were revealed to have normal hearing after follow-up hearing test, which were associated with cleft palate, hyperbilirubinemia or prematurity. One of them had 235delC mutation of the connexin26, and the temporal bone CT scan demonstrated the finding of enlarged vestibular aqueduct syndrome (EVAS) in one infant. Two infants participated in the connected speech rehabilitation program and showed significant development of language. CONCLUSION: Follow-up hearing tests are important in case of failures of newborn hearing screening test. The establishment of auditory and speech rehabilitation program connected with newborn hearing screening is essential in treating hearing-impaired neonates.