Korean J Otorhinolaryngol-Head Neck Surg.  2015 Jun;58(6):389-394. 10.3342/kjorl-hns.2015.58.6.389.

Role of Cochlear Microphonic in Newborn Hearing Test

• Kwak MK
• Chung JH
• Park CW
• Kim KR
• Kim SW
• Lee SH

• KMID: 2141127
• DOI: http://doi.org/10.3342/kjorl-hns.2015.58.6.389

Abstract

BACKGROUND AND OBJECTIVES
Cochlear microphonic (CM) is an electrical potential generated by outer hair cells in response to acoustic stimulation. The aim of this study is to evaluate the significance of CM in neonatal hearing loss.
SUBJECTS AND METHOD
From April 2013 to April 2014, 64 neonates hospitalized in neonatal intensive care unit were enrolled. Subjects underwent transient evoked otoacoustic emission (TEOAE), auditory brain stem response (ABR) and CM. We analyzed the results of hearing tests and the correlation between CM and the other test modalities.
RESULTS
Ninety two ears showed normal ABR waves whereas the other 36 ears had abnormal ABR. There were two neonates who were suspected of auditory neuropathy because of the presence of TEOAE and CM. Among 14 ears who showed abnormal OAE results, 12 ears (86%) were identified as having CM. The amplitudes of CMs were correlated with the reproducibility of TEOAE (p<0.005). Between the ears with positive TEOAE and others with negative TEOAE, the amplitudes of CMs were significantly different (p<0.005).
CONCLUSION
Many ears were identified with the presence of CM without TEOAE response because of the the vulnerability of OAE from middle ear status and environment. We suppose that CM might provide information on outer hair cell function to complement the OAE in neonatal hearing test.

Keyword

Auditory neuropathy; Cochlear microphonic potentials; Hearing loss; Neonatal screening

MeSH Terms

Acoustic Stimulation
Cochlear Microphonic Potentials
Complement System Proteins
Ear
Ear, Middle
Evoked Potentials, Auditory, Brain Stem
Hair
Hearing Loss
Hearing Tests*
Humans
Infant, Newborn*
Intensive Care, Neonatal
Neonatal Screening
Complement System Proteins