Biomaterial Database

Extratympanic electrocochleographic changes on noise-induced temporary threshold shift. 2004

Eui-Cheol Nam, and Jun Yeon Won

Department of Otolaryngology, Kangwon National University Hospital, Chunchon, Kangwon, Korea. birdynec@kangwon.ac.kr

OBJECTIVE Electrocochleography (ECoG) is a sensitive evoked-response test for evaluating changes in cochlear function. We investigated the extratympanic ECoG in a noise-induced temporary threshold shift (TTS) to evaluate the usefulness of ECoG in the early detection of noise-induced hearing loss (NIHL). METHODS In a prospective analysis, 15 healthy ears were exposed to 90.3- to 105.0-dB noise for 3 hours in the same computer-game arcade. Pure-tone audiometry and ECoG were performed before, immediately after, and 24 hours after the exposure. RESULTS Before the exposure, the average hearing level was 5.8 +/- 2.7 dB, which increased significantly to 12.8 +/- 2.8 dB immediately after exposure. A marked increment in the SP/AP (summating potential/action potential) ratio was observed with the TTS. The mean ratio was 0.22 +/- 0.11 before the exposure, 0.46 +/- 0.18 in the TTS phase, and 0.20 +/- 0.11 after resolution. CONCLUSIONS The results of this study suggest that the SP/AP ratio is useful for the early detection and monitoring of NIHL.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011446	Prospective Studies	Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.	Prospective Study,Studies, Prospective,Study, Prospective
D005260	Female		Females
D006317	Hearing Loss, Noise-Induced	Hearing loss due to exposure to explosive loud noise or chronic exposure to sound level greater than 85 dB. The hearing loss is often in the frequency range 4000-6000 hertz.	Acoustic Trauma,Hearing Loss, Noise Induced,Noise-Induced Hearing Loss
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D001300	Audiometry, Evoked Response	A form of electrophysiologic audiometry in which an analog computer is included in the circuit to average out ongoing or spontaneous brain wave activity. A characteristic pattern of response to a sound stimulus may then become evident. Evoked response audiometry is known also as electric response audiometry.	Audiometry, Electroencephalic Response,Electrocochleography,Evoked Response Audiometry,Audiometries, Electroencephalic Response,Audiometries, Evoked Response,Electrocochleographies,Electroencephalic Response Audiometries,Electroencephalic Response Audiometry,Evoked Response Audiometries,Response Audiometries, Electroencephalic,Response Audiometries, Evoked,Response Audiometry, Electroencephalic,Response Audiometry, Evoked
D001309	Auditory Threshold	The audibility limit of discriminating sound intensity and pitch.	Auditory Thresholds,Threshold, Auditory,Thresholds, Auditory
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor