Clinical considerations in the interpretation of auditory brainstem response audiometry

Auditory brainstem response (ABR) audiometry which monitors the electrical activity of the auditory nerve and brainstem nuclei, has provided a new technique in the diagnosis of neurological dysfunction and peripheral hearing deficits. Brainstem potentials consist of seven waves, each separated in latency by approximately one millisecond and each representing successively higher order neuron activity of the auditory pathway. The criteria used for ABR interpretation are based primarily on the latency of individual were peaks and their interpeak latencies. Due to its consistency and stability, the fifth wave has been considered prominent in the interpretation of auditory threshold sensitivity. Unfortunately, Wave V latency-intensity function may be affected by extrinsic and intrinsic variables. Consequently, in order to establish diagnostic criteria that are comparable, the elimination and/or control of these variables must be examined. Therefore, the purpose of this paper is to report the effects of various pathological and nonpathological conditions which contribute to difference in ABR audiometry interpretation.