Effect of Age on Spectral Distribution of Click and Tone burst Evoked Oto acoustic Emissions in Infants

Abstract

Otoacoustic emission (OAE) is a sensitive tool used to assess the functional status of the outer hair cells (i.e.,the cochlear component most vulnerable to many of the diseases and disorders that damage hearing) in infants with normal hearing and in different clinical population . The present study aimed to investigate the influence of age on click and tone burst evoked OAEs, to investigate the pattern of frequency shift with age. and to monitor the frequency specific maturational changes in the cochlea. The study was conducted on 40 infants (80ears) with normal hearing sensitivity in the age range of 0 to 12 months. with subgroups as group I, II, III, IV. The results of the present study revealed that, the mean absolute amplitude of click and tone burst evoked OAEs across age groups increased as the age increased. Similarly, the mean SNR values of click evoked OAEs across age groups increased as the age increases. Whereas. the mean SNR values of tone burst evoked OAEs across age groups increased as the age increases, except for group 1. Also, statistically significant difference for mean absolute amplitude was observed between CEOAEs and TBOAEs across all the frequencies. These findings can be used as a clinical tool for screening and diagnostic purposes in the pediatric population .