Comparison between audiometric and ABR thresholds in children. Contradictory findings.
The aim of the study was to predict hearing level thresholds with click-evoked ABR and to study the residual hearing when ABR was absent. In 85 hearing-impaired children, the conclusive pure-tone hearing level thresholds are reported. The exclusion criterion used was deteriorating hearing loss. The Jewett V-wave was identified in 48.2% of the subjects and was bilaterally absent in 51.8%. The correlation between ABR and PTA (2-4 kHz) thresholds was significant (P < 0.01). Audiometrically, 65.9% of the children with no response on ABR had hearing, and in 34.5% of these, the hearing loss was sloping. The median PTA (2-4 kHz) was 102 dB and the range from 65 to 120 dB. The accuracy of ABR is reasonably ineffective, because it overestimates the hearing loss in moderate and severe impairments. The absence of ABR indicates a significant hearing loss, but PTAs (2-4 kHz) as good as 65 dB were still found. Thus, a lack of response to click stimuli does not directly suggest none-viable residual hearing.
Marttila
Timo I
TI
Department of Audiology, Ear, Nose and Throat Clinic of Helsinki University Central Hospital, Finland. timo.marttila@hus.fi
Karikoski
Jukka O
JO
D000293:Adolescent; D000328:Adult; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D002648:Child; D002675:Child, Preschool; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D034381:Hearing Loss / Q000175:diagnosis*; D006320:Hearing Tests / Q000379:methods*; D006801:Humans; D007223:Infant; D008297:Male