Study of Cochlear Microphonic Potentials in Auditory Neuropathy
Brazilian Journal of Otorhinolaryngology
Soares, I. D., Menezes, P. L., et al. (2016).
Brazilian Journal of Otorhinolaryngology, 82(6), 722-736.
This systematic review investigates the observation of cochlear microphonics to diagnose individuals with auditory neuropathy spectrum disorder.
Not stated
Through July 2014
Original studies; case reports; literature reviews
14
There is agreement in the literature that, "the presence of the CM [cochlear microphonic] becomes the determinant finding in the differential diagnosis of AN [auditory neuropathy]" in individuals because "even at an advanced state of AN, CM remains present" (p. 735) while otoacoustic emissions (OAEs) may fluctuate over time.<div><br /></div><div>The characteristics of CM in individuals with auditory neuropathy include:</div><div><ul> <li>a longer CM duration for those with AN as compared to individuals with normal hearing and</li> <li>no significant difference in CM amplitude for individuals with AN as compared to those with normal hearing.</li></ul></div>
Cochlear microphonics (CM) for diagnosing auditory neuropathy in individuals can be observed using either auditory brainstem response (ABR) or transtympanic electrocochleography (EcogT). While ABR for individuals with auditory neuropathy is absent, EcogT is the "gold standard tool to evaluate CM because Ecog allows a more detailed analysis of cochlear function in relation to ABR" (p. 735).
