Background and Objectives: In neonates with hyperbilirubinemic sensorineural hearing loss, the lesion site is supposed to be confined to the retrocochlea. The purpose of this study is to investigate the changes of hearing level and the
progression of the lesion site involving cochlear area after a lapse of time in the patients with hyperbilirubinemic sensorineural hearing loss.
Materials and Method: ABR, TEOAE and IA tests were performed on 11 neonates with severe hyperbilirubinemia with exchange transfusion in the period of neonates. After more than 4 years, follow-up ABR, TEOAE, and IA tests were carried out in
the
same 11 children.
Results: In the initial ABR test, 4 neonates showed abnormal or no response and the other 7 neonates demonstrated normal response. All 11 neonates passed TEOAE and showed A type in IA In the follow-up tests after more than 4 years, 7
children who
had shown normal ABR, TEOAE and IA test results as neonates showed normal ABR, TEOAE, and IA. In 4 children who had abnormal ABR results, showed decreased ABR thresholds. In TEOAE, 3 children showed bilateral failures and 1 child showed
unilateral
failure.
Conclusions: The results of this study suggests that the sites of lesion in hearing loss caused by hyperbilirubinemia were at the retrocochlear location as neonates. But the lesions may affect the cochlear lesions after a lapse of time. And
some
residual hearing may be preserved.
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