Electrocochleography: applications and limitations in young children.

Electrophysiological measurements of auditory function are especially indicated in children who are difficult to test by behavioral audiometry. This report is concerned with transtympanic electrocochleography (ECochG) findings in young children (0-3 years) who were examined over the last 6 years in order to extend behavioral audiometric data. On an average, 25% of the children tested with auditory brainstem responses (ABR) needed general anesthesia and were therefore also investigated with ECochG (n = 65). These ECochG children often showed developmental retardation, and behavioral audiometry was doubtful or not possible in 60% of them. ECochG thresholds were generally similar on both ears. Despite general agreement between thresholds obtained by ECochG and behavioral audiometry, differences were found in both directions, ECochG being better or worse than hearing in several children. Detection of severe threshold elevation and low frequency residual hearing remain major limitations of ECochG in the early diagnosis and rehabilitation of deafness in young children.