Electrocochleography (ECochG)
Electrocochleography is a diagnostic test that measures electrical potentials generated in the cochlea and auditory nerve in response to sound stimulation. A recording electrode is placed near or on the eardrum or in the ear canal, and sounds are presented to the ear. The test measures three main components: the cochlear microphonic (reflecting outer hair cell function), the summating potential (reflecting cochlear fluid mechanics), and the compound action potential of the auditory nerve.
ECochG is most commonly used in the assessment of Meniere's disease. An abnormal ratio between the summating potential and the action potential can indicate endolymphatic hydrops, the fluid imbalance in the inner ear associated with that condition. The test is also used to monitor cochlear function during certain surgeries and as part of cochlear implant candidacy evaluations.
The procedure is non-invasive and can be performed in an audiology clinic. Results are interpreted alongside other audiological and vestibular findings.
