Hearing threshold assessment with auditory brainstem response (ABR) and ElectroCochleoGraphy (ECochG) in...

Two-hundred-and-sixty uncooperative children (442 ears) performed auditory brainstem response (ABR) and Electrocochleography (ECochG) in the same diagnostic session under general anaesthesia, and the results obtained with the two different methods were compared. A difference > or = 20 dB between the two methods was found in 134 ears (30.3%). The presence of middle ear effusion and symptoms of a possible central nervous system pathology were considered in order to verify the evidence of a correlation between the difference in ABR-ECochG results and these clinical parameters. The presence of middle ear effusion was not significantly correlated with differences > or = 20 dB (p = 0.1347). On the contrary, the presence of symptoms indicative of a possible central nervous system (CNS) involvement was significantly correlated with differences > or = 20 dB (p = 0.0000). ABR has to be considered the first choice in hearing assessment strategy, either for screening or diagnosis. However, the diagnosis of hearing loss only on the basis of the presence or absence of wave V requires some care in case of suspected central auditory pathway lesions. In these cases, ECochG may be the only reliable diagnostic tool for hearing assessment in uncooperative subjects.