Extratympanic Electrocochleography with Coats Electrode

Chon, Kyong-Myong; Goh, Eui-Kyung; Yoon, Jae Seoung; Roh, Hwan-Jung

doi:10.35420/jcohns.1994.5.2.201

J Clin Otolaryngol Head Neck Surg 1994; 5(2):201-211

pISSN: 1225-0244, eISSN: 2713-833X

DOI: https://doi.org/10.35420/jcohns.1994.5.2.201

원저

Coats Electrode를 이용한 고막외적 유도법에 의한 전기와우도

전경명¹, 고의경¹, 윤종근¹, 노환중¹

Extratympanic Electrocochleography with Coats Electrode

Kyong-Myong Chon¹, Eui-Kyung Goh¹, Jae Seoung Yoon¹, Hwan-Jung Roh¹

Author Information & Copyright ▼

¹부산대학교 의과대학 이비인후과학교실

¹Department of Otolaryngology, College of Medicine, Pusan National University

© Copyright 1994 The Busan, Ulsan, Gyeoungnam Branch of Korean Society of Otolaryngology-Head and Neck Surgery. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Published Online: May 31, 2020

ABSTRACT

Electrocochleography(ECoG) is a method of recording the stimulus-related potentials of the cochlear and auditory nerve. Clinically the electrodes used for ECoG recording in human are classified as invasive or noninvasive depending on whether or not they penetrate the ear drum. Non-invasive extratympanic ECoG was performed on 46 normal hearing ears and 40 ears with positive recruitment of other origin than endolymphatic hydrops with Coats electrode. We have measured the normal value of latency and amplitude of SP, AP and SP/AP ratio at 87dB HL of alternating broad band & IK, 4K, 8KHz narrow band click sound and compared the latency and amplitude on normal hearing ears and cochlear learing ears at same condition.

We also compared the amplitiude and the latency of SP, AP and SP/AP with transtympanic and extratympanic ECoG in normal hearing ear.

The results were as follows:

There were no significant different latency and amplitude of SP and AP according to frequency of click stimuli. And maxiuni value of amplitude with minium SD was obtained at broad band click. In normal hearing ears, the amplitude of SP and that of AP were 0.58±0.44 and 4.14±0J4respectively and the latencies of SP and AP were 1.09±0.14msec and 1.66±0.11msec respecitvley at 87dB HL broad band click.
There were significant decreased amplitudes of SP and AP of cochlear hearing loss ears than normal hearing ears at each frequencies(p<0.05).
There were significant prolonged latencies of SP and AP of cochlear hearing loss ears than normal hearing ears at each frequencies.
Although the amplitudes of SP and AP with noninvasive extratympanic ECoG were 1/6 to 1/7 of that with invasive ttranstympanic ECoG, SP/AP with extratympanic and transtympanic ECoG of normal hearing ears were nearly equal and about 0.46.
Authors concluded that extratympanic ECoG recording with Coats electrode is enough diagnostic tool for inner ear disease.

Keywords: Extratympanic ECoG; Coats electrode