Electrocochleography: Using Extratympanic or Transtympanic Methods?

Abstract

The advantages and disadvantages of the transtympanic and extratympanic methods for recording electrocochleographic potentials (ECochG) are discussed. Our extratympanic method (adapted from Coats) and some results are presented. We conclude that for broad clinical application an ear canal surface electrode is the method of choice for recording ECochG, unless the primary question is one of threshold measurement. If the registration of brainstem potentials from the vertex does not show a potential I, we recommend simultaneous recording of ECochG by an extratympanic method with earphones.

Noninvasive detection of alarming intracranial pressure changes by auditory monitoring in early management of brain injury: a prospective invasive versus noninvasive study

“…CM measurements have been routinely used for decades in audiology [ 15 ]. The present protocol is sufficiently user-friendly to be implemented by nurses whose tasks are to position an earplug in the external auditory meatus and two skin electrodes on the forehead of the patients.…”

Using a Concha Electrode to Measure Response Patterns Based on the Amplitudes of Cochlear Microphonic Waveforms Across Acoustic Frequencies in Normal-Hearing Subjects

“…It is very challenging, since developing an approach is not the same as validating an approach. By reviewing some relevant history, three steps can be generalized: developing an electrode, developing approaches of using the electrode, and developing applications to apply the approaches (Gersdorff 1982;Probst 1983;Stevens et al 1983;Kemp & Brown 1984;Aso & Gibson 1994;Nam & Won 2004;Santarelli et al 2006;Morawski et al 2007;Attias et al 2008).…”

“…Because of the limitations of round window electrodes, the tympanic membrane electrode and the ear-canal electrode were developed. Each electrode has many approaches for its use (Gersdorff 1982;Probst 1983;Stevens et al 1983;Kemp & Brown 1984;Aso & Gibson 1994;Nam & Won 2004;Santarelli et al 2006;Morawski et al 2007;Attias et al 2008). By considering the limitations of the ear-canal electrode, the concha electrode was developed, along with approaches for its use in measuring CMs and ABRs (Zhang 2010).…”

Response Pattern Based on the Amplitude of Ear Canal Recorded Cochlear Microphonic Waveforms across Acoustic Frequencies in Normal Hearing Subjects

“…Although using a tympanic membrane electrode or an invasive intratympanic electrode in the clinic has allowed us to record a very robust response signal, an ear canal electrode which is less invasive and more convenient has also been successfully used to record electrocochleograms and its use has been well documented since 1983 (Chatrian, Wirch, Edwards, Lettich, & Snyder, 1984;Coats, 1986;Ferraro, Blackwell, Mediavilla, & Thedinger, 1994;Ghosh, Gupta, & Mann, 2002;Mori, Asai, Doi, & Matsunaga, 1987;Pappas, Pappas, Carmichael, Hyatt, & Toohey, 2000;Probst, 1983;Roland, Yellin, Meyerhoff, & Frank, 1995;Zhang et al, 2003). Therefore, we have also adopted the ear canal electrode in our study.…”