[Audiology characteristics in newborns and infants who failed in the hearing screening by transiently evoked otoacoustic emissions: 89 cases study].

OBJECTIVE

The present study was to evaluate the audiological characteristics of infants with normal auditory brainstem response thresholds in click and abnormal transiently evoked otoacoustic emissions. Relationships between test results of distortion product otoacoustic emissions (DPOAE) and other hearing testing methods were also evaluated.

METHODS

The participants consisted of eighty-nine infants, with a total of 123 ears. All participants' TEOAE screening results were abnormal but diagnostic click ABR results were normal. The participants were classified into the following groups based on the test results from distortion product otoacoustic emissions: group A (normal all-frequency), group B (abnormal low-frequency), group C (abnormal high-frequency), and group D (abnormal all-frequency).

RESULTS

Obtained from these groups were compared to results of other hearing tests including the latency of ABR wave I, 40 Hz auditory event related potential (40 Hz AERP), 226 Hz and 1000 Hz tympanometry, and acoustic reflex. Results In six hearing tests in the 123 ears, seven ears (5.7%) were normal, while 116 ears (94.3%) were abnormal. No significantly differences were detected between boys (93.9%) and girls (95.1%), as well as between left (93.1%) and right ears (95.4%). The proportion of abnormal test results ranked as follows: 59 ears in group D (48.0%), 34 ears in group B (27.6%), 20 ears in group A (16.3%), and 10 ears in group C (8.2%). The highest abnormal rates in groups A, B and D were acoustic reflex, which were 40.0% for group A, 55.9% for group B and 66.1% for group D respectively. The highest abnormal rate in group C was the latency of ABR wave I (50.0%). Distribution of low-frequency hearing loss in each group was mainly mild. However, one ear in group B was moderate hearing loss, six ears in group D were moderate hearing loss, and one ear in group D was severe hearing loss.

CONCLUSIONS

The present study showed that, of which infants with normal thresholds of ABR failed the hearing screening, comprehensively audiology assessment is needed. And of which infants with normal DPOAE in full frequency or abnormal in high frequency region or low frequency region need to be followed up.