Biomaterial Database

Vulnerability to acoustic trauma in the normal hearing ear with contralateral hearing loss. 2014

Hyun Woo Lim, and Ji Won Lee, and Jong Woo Chung

Department of Otolaryngology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.

OBJECTIVE We undertook an animal study to investigate the functional and histological changes that occur in the normal hearing ear of following acoustic trauma. METHODS As an animal model of unilateral hearing loss, the right ears of CBA mice were deafened by cochlear destruction at 6 weeks of age (SSD group). The control groups included mice that underwent a sham surgery, and mice that were exposed to noise binaurally and monaurally (by plugging the right ear completely). At 10 weeks of age, all mice were exposed to acoustic trauma (110 dB sound pressure level for 1 hour) that induced a transient threshold shift (TTS). Changes in the hearing thresholds of the left ear were assessed over the next 4 weeks by measuring the auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). RESULTS Following the noise exposure, the SSD group showed a permanent threshold shift (PTS) of about 10 dB, whereas the other groups showed full recovery from the TTS. The threshold of the DPOAEs of the left ears were increased after noise exposure but returned to normal in all groups, with no significant differences among the groups. Histological evaluation showed no apparent cellular loss or apoptosis in the left ears of all groups, including the SSD group. CONCLUSIONS These results suggest that normal hearing ears are more vulnerable to acoustic trauma following contralateral unilateral cochlear ablation. This increased vulnerability may be due to damaged neural structures.

UI	MeSH Term	Description	Entries
D008808	Mice, Inbred CBA	An inbred strain of mouse that is widely used in BIOMEDICAL RESEARCH.	Mice, CBA,Mouse, CBA,Mouse, Inbred CBA,CBA Mice,CBA Mice, Inbred,CBA Mouse,CBA Mouse, Inbred,Inbred CBA Mice,Inbred CBA Mouse
D003051	Cochlea	The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.	Cochleas
D004195	Disease Models, Animal	Naturally-occurring or experimentally-induced animal diseases with pathological processes analogous to human diseases.	Animal Disease Model,Animal Disease Models,Disease Model, Animal
D004198	Disease Susceptibility	A constitution or condition of the body which makes the tissues react in special ways to certain extrinsic stimuli and thus tends to make the individual more than usually susceptible to certain diseases.	Diathesis,Susceptibility, Disease,Diatheses,Disease Susceptibilities,Susceptibilities, Disease
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
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001309	Auditory Threshold	The audibility limit of discriminating sound intensity and pitch.	Auditory Thresholds,Threshold, Auditory,Thresholds, Auditory
D016057	Evoked Potentials, Auditory, Brain Stem	Electrical waves in the CEREBRAL CORTEX generated by BRAIN STEM structures in response to auditory click stimuli. These are found to be abnormal in many patients with CEREBELLOPONTINE ANGLE lesions, MULTIPLE SCLEROSIS, or other DEMYELINATING DISEASES.	Acoustic Evoked Brain Stem Potentials,Auditory Brain Stem Evoked Responses,Brain Stem Auditory Evoked Potentials,Evoked Responses, Auditory, Brain Stem,Acoustic Evoked Brain Stem Potential,Acoustic Evoked Brainstem Potential,Acoustic Evoked Brainstem Potentials,Auditory Brain Stem Evoked Response,Auditory Brain Stem Response,Auditory Brain Stem Responses,Auditory Brainstem Evoked Response,Auditory Brainstem Evoked Responses,Auditory Brainstem Responses,Brain Stem Auditory Evoked Potential,Brainstem Auditory Evoked Potential,Brainstem Auditory Evoked Potentials,Evoked Potential, Auditory, Brainstem,Evoked Potentials, Auditory, Brainstem,Evoked Response, Auditory, Brain Stem,Evoked Response, Auditory, Brainstem,Evoked Responses, Auditory, Brainstem,Auditory Brainstem Response,Brainstem Response, Auditory,Brainstem Responses, Auditory,Response, Auditory Brainstem,Responses, Auditory Brainstem
D017084	Otoacoustic Emissions, Spontaneous	Self-generated faint acoustic signals from the inner ear (COCHLEA) without external stimulation. These faint signals can be recorded in the EAR CANAL and are indications of active OUTER AUDITORY HAIR CELLS. Spontaneous otoacoustic emissions are found in all classes of land vertebrates.	Spontaneous Otoacoustic Emissions,Otoacoustic Emission, Spontaneous,Spontaneous Otoacoustic Emission
D046088	Hearing Loss, Unilateral	Partial or complete hearing loss in one ear.	Deafness Unilateral,Unilateral Hearing Loss,Deafness, Unilateral,Unilateral Deafness,Unilateral, Deafness