Electrocochleography

The cochlear summating potential reflects an electrical response generated within the cochlea, while the auditory-nerve compound action potential represents synchronized activity from auditory-nerve fibers. Electrocochleography examines these evoked potentials through their timing and amplitude after sound stimulation. Considering both measures helps clinicians assess cochlear and auditory-nerve function rather than relying only on behavioral hearing responses.

Amplitude indicates the size of a recorded electrical response, whereas timing describes when that response occurs after sound stimulation. These complementary features provide objective information about cochlear and auditory-pathway activity. Their interpretation can strengthen assessment when combined with hearing tests and other vestibular or neurologic evaluations, although the measurements are intended to complement rather than replace those assessments.

Electrocochleography can use surface electrodes or transtympanic electrodes to detect sound-evoked potentials. Regardless of the approach, the recording focuses on electrical activity from the cochlea and auditory nerve, including the summating potential and compound action potential. The electrode configuration therefore forms the measurement interface through which clinicians obtain objective electrophysiological evidence of inner-ear and auditory-pathway function.

In suspected auditory neuropathy, electrocochleography contributes objective evidence about cochlear and auditory-nerve activity after sound stimulation. Its recorded evoked potentials can be considered alongside hearing-test findings and other evaluations of the auditory pathway. This combined approach helps place electrophysiological observations within a broader clinical assessment rather than treating a single recording as a complete evaluation.

A typical recording applies sound stimulation while electrodes detect the resulting electrical responses. The system captures evoked potentials associated with the cochlea and auditory nerve, including the summating potential and compound action potential. Clinicians then examine response timing and amplitude to characterize activity and integrate those findings with hearing, vestibular, or neurologic information relevant to the clinical question.

Electrocochleography supports the evaluation of Ménière’s disease and suspected endolymphatic hydrops by providing objective measurements of sound-evoked cochlear and auditory-nerve activity. These recordings add electrophysiological evidence to the clinical workup. Interpretation is most useful when combined with hearing tests and other vestibular or neurologic evaluations, which provide complementary information about the patient’s condition.

During procedures, electrocochleography can monitor cochlear and auditory-nerve activity in real time or across procedural stages. Recording evoked potentials provides an objective way to follow these structures while the intervention is being performed. This monitoring application differs from diagnostic assessment because the emphasis is on observing activity during the procedure, while still using response timing and amplitude as key measurements.