Bone conduction masking for brainstem auditory-evoked potentials (BAEP) in pediatric audiological evaluations. Validation of the test.

A brainstem auditory-evoked potential (BAEP) protocol for testing pediatric patients at risk for conductive hearing impairment was evaluated. The protocol used was: air-conducted click stimuli masked by bone-conducted wide-band noise. The specificity and sensitivity values for the test were determined by means of a blind cross-sectional trial including an active group of patients with an aural malformation and an age-matched control group with a sensorineural impairment. The bone-conducted masking of air-conducted BAEP showed high specificity and sensitivity and was easily administered despite pediatric difficulty. It was useful in differentiating sensorineural from conductive impairment and provided a rough estimate of the cochlear reserve in presumptive conductive hearing loss as great as 60 dB hearing loss. It is concluded that the bone-conducted masking procedure appears to be a great help in the binary decision whether middle ear surgery should be performed in patients at risk for conductive hearing loss, specially children with aural malformations.