All issues > Volume 38(10); 1995

Original Article

J Korean Pediatr Soc. 1995;38(10):1315-1323. Published online October 15, 1995.

Analysis of Auditory Brainstem Response in the Infants at High Risk for Hearing Disability

Kang Ho KH Cho¹, Myoung Jae MJ Chey²

¹Department of Pediatrics, Chungang Gil Hospital, Korea
²Department of Pediatrics, College of Medicine, Inje University, Sanggye Paik Hospital, Korea

Abstract

Purpose
: This study is performed to evaluate the clinical course, degree of hearing impairment and neurologic outcome of the infants at high risk for hearing disability.
Methods
: The 603 infants who had risk factors, such as severe birth asphyxia, hiperbilirubinemia requiring exchange transfusion, head and neck anomaly every low birthweight under 1500gm, family history of childhood hearing impairment, bacterial meningitis or congenital infection who were admitted to neonatal intensive care unit of Chungang Gil Hospital from Jun. 1989 to Jun. 1993, were evaluated with their ABR.
Results
: 1) Twenty-four cases(40%) among 603 high risk infants for hearing disability had severely abnormal findings in ABR, and 12 cases showed bilateral, 9 cases showed asymmetric and 3 cases showed unilateral abnormality. 2) Bilateral flat waves were in 5 cases, bilateral nearly flat waves in 4 cases, and bilateral loss of wave V at 45dB in 3 cases 3) Twelve cases of birth asphyxia, 7 cases of hyperbilirubinemia, 1 case of Down syndrom and 4 cases of microtia were found as the risk factors for hearing disability. 4) During the follow up of 17 cases, major neurologic defect was found in 3 cases, minor neurologic defect in 4 cases, sensory-neural hearing loss with neurologic defect in 5 cases, sensory-neural hearing loss without neurologic defect in 1 case, and normal in 5 cases. Neurologic outcome of 4 cases was not included because their follow up duration was shorter than 3 months. 5) Amont 3 cases of major neurologic defect, the result of brain sonography in 2 cases was normal. 6) Among 8 cases of bilateral abnormal waves, 5 cases showed neurologic abnormality during follow up. 7) In the retest of 7 ABR cases, 2 cases showed no chage, 4 cases showed mild improvement and 1 case returned to normal.
Conclusion
: We recommend ABR as screening test in NICU to detect the hearing disability or neurologic abnormality in high risk infants.

Keywords :Auditory branstem response (ABR), Neurologic outcome, Hearing disability, Neonate