Electrical Stimulation of the Auditory Nerve via Cochlear Implants in Patients with Auditory Neuropathy

Auditory neuropathy (AN) is a term used to describe an auditory disorder in which there is evidence of normal outer hair cell function (otoacoustic emissions and/or cochlear microphonics) and poor function of the auditory nerve (absent or highly distorted auditory brain stem response starting with wave I). Many of these patients have evidence of generalized peripheral nerve disease, leading to an assumption that the peripheral portion of the auditory nerve is the most likely site of lesion. A small group of these patients has received cochlear implants, and the majority of them achieve average to above-average performance. Although this outcome may seem incongruous with neural disease, average performance by patients with AN may be a result of the reintroduction of neural synchrony by electrical stimulation and/or the fact that most deaf patients have poor nerve survival. Although cochlear implants are promising for deaf patients with AN, more study of the disorder is needed.

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Acquired auditory neuropathy spectrum disorder after malaria treated with quinine

Tropical Doctor ◽

10.1177/0049475520917236 ◽

2020 ◽

Vol 50 (3) ◽

pp. 246-248

Author(s):

Helen Brough

Keyword(s):

Auditory Nerve ◽

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Cell Function ◽

Auditory Brainstem ◽

Auditory Neuropathy ◽

Spectrum Disorder ◽

Auditory Neuropathy Spectrum Disorder ◽

Acoustic Reflexes ◽

Brainstem Response

Auditory neuropathy spectrum disorder (ANSD) can cause significant hearing impairment; it occurs when there is intact outer hair cell function in the inner ear, with a dyssynchronous neural response, thought to be due to dysfunction of the inner hair cells (IHCs), the synapse of the IHCs and the auditory nerve, or of the auditory nerve itself. This case report describes the onset of ANSD in a Malawian child after severe malaria treated with quinine. Diagnosis of ANSD was made by confirming the presence of otoacoustic emissions, together with the absence of auditory brainstem response and absent acoustic reflexes.

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Changes in Otoacoustic Emissions and Auditory Brain Stem Response after C/s-Platinum Exposure in Gerbils

Otolaryngology ◽

10.1016/s0194-5998(97)70232-8 ◽

1997 ◽

Vol 116 (6) ◽

pp. 585-592 ◽

Cited By ~ 15

Author(s):

Kathleen C. Y. Sie ◽

Susan J. Norton

Keyword(s):

Hearing Loss ◽

Brain Stem ◽

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Outer Hair Cells ◽

Distortion Product Otoacoustic Emissions ◽

Auditory Brain Stem Response ◽

Distortion Product ◽

Auditory Brain Stem ◽

Significant Difference

Ototoxicity associated with cis-platinum administration commonly presents as hearing loss and tinnitus. The hearing loss is usually an irreversible, high-frequency sensorineural loss. Histologic studies in humans and animals suggest that the outer hair cells (OHCs) are most susceptible to cis-platinum. Evoked otoacoustic emissions (EOAE), as a measure of outer hair cell function, are potentially useful in following ototoxic insults involving OHCs. Distortion-product otoacoustic emissions (DPOAE) test frequency-specific regions of the cochlea and therefore may be particularly well suited for monitoring ototoxic injuries. We measured distortion product otoacoustic emissions, at f2 = 2, 4, 6, 8, 10, and 12 kHz, in gerbils after a single large dose of cis-platinum. Animals treated with saline served as controls. The findings were compared to auditory brain stem evoked response (ABR) thresholds, using tone pips of the same frequencies. The DPOAE and ABR thresholds were measured before treatment and again 2, 5, and 14 days after drug administration. The changes in DPOAE were compared with the changes in ABR. No treatment effect was noted in the 2-day group. Animals treated with c/s-platinum demonstrated significant elevation of DPOAE and ABR thresholds compared with control animals at 5 and 14 days. There was no significant difference between the threshold changes in the 5-and 14-day groups.

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Late-Onset Unilateral Auditory Neuropathy/Dysynchrony: A Case Study

Journal of the American Academy of Audiology ◽

10.3766/jaaa.20.3.3 ◽

2009 ◽

Vol 20 (03) ◽

pp. 172-179 ◽

Cited By ~ 4

Author(s):

Andrew Stuart ◽

Kristal N. Mills

Keyword(s):

Otoacoustic Emissions ◽

Late Onset ◽

Internal Auditory Canal ◽

Auditory Neuropathy ◽

Auditory Brain Stem Response ◽

Affected Side ◽

Auditory Brain Stem ◽

Long Latency ◽

Acoustic Reflexes

Background: Auditory neuropathy/dysynchrony (AN/AD) typically develops early in life and is bilateral in nature. Purpose: Herein, we describe an unusual finding of late-onset unilateral AN/AD based on reported case history and audiometric findings. Research Design: A 64-year-old female presented with a complaint of a progressive unilateral hearing loss that had developed over the past two–three years. She underwent an extensive behavioral/electrophysiological test battery. Results: Magnetic resonance imaging was negative for internal auditory canal mass or lesion. A unilateral notched loss centered at 1000 Hz and other findings were consistent with late-onset unilateral AN/AD: observable bilateral otoacoustic emissions and cochlear microphonics, absent middle acoustic reflexes with stimulation on the affected side, abnormal auditory brain stem response on the affected side, and poorer speech recognition than would be predicted by the audiogram. Middle-latency and long-latency evoked responses were present bilaterally, although with lower amplitudes on the affected side.

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DPOAE-Grams in Patients with Acute Tonal Tinnitus

Otolaryngology ◽

10.1016/j.otohns.2004.09.031 ◽

2005 ◽

Vol 132 (4) ◽

pp. 550-553 ◽

Cited By ~ 24

Author(s):

Haralampos Gouveris ◽

Jan Maurer ◽

Wolf Mann

Keyword(s):

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Cell Function ◽

Hearing Threshold ◽

Normal Hearing ◽

Outer Hair Cells ◽

Controlled Study ◽

High Frequency Region ◽

Mean Values ◽

Distortion Products

OBJECTIVE: To investigate cochlear outer hair cell function in patients with acute tonal tinnitus and normal or near-normal hearing threshold. STUDY DESIGN AND SETTING: Prospective controlled study in an academic tertiary health center. Distortion products of otoacoustic emissions (DPOAE)-grams of 32 ears with acute tonal tinnitus and normal hearing or minimal hearing loss were compared with those of 17 healthy nontinnitus ears. RESULTS: Tinnitus ears exhibited relatively increased amplitudes of DPOAE at high frequencies (4-6.3 kHz) when compared with the group of healthy ears and relatively decreased DPOAE amplitudes at middle frequencies (1650-2400 Hz). Statistically significant ( P < 0.01) increased mean values of DPOAE amplitudes were observed only at a frequency of f2 equal to 4.9 kHz. CONCLUSIONS AND SIGNIFICANCE: These findings suggest an altered functional state of the outer hair cells at a selected high-frequency region of the cochlea in ears with acute tonal tinnitus and normal or near-normal hearing threshold.

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Cochlear Receptor (Microphonic and Summating Potentials, Otoacoustic Emissions) and Auditory Pathway (Auditory Brain Stem Potentials) Activity in Auditory Neuropathy

Ear and Hearing ◽

10.1097/00003446-200104000-00002 ◽

2001 ◽

Vol 22 (2) ◽

pp. 91-99 ◽

Cited By ~ 80

Author(s):

A. Starr ◽

Y. Sininger ◽

T. Nguyen ◽

H. J. Michalewski ◽

S. Oba ◽

...

Keyword(s):

Brain Stem ◽

Otoacoustic Emissions ◽

Auditory Pathway ◽

Auditory Neuropathy ◽

Auditory Brain Stem ◽

Auditory Brain Stem Potentials

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Incidence of Cochlear Involvement in Hyperbilirubinemic Deafness

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348940211101113 ◽

2002 ◽

Vol 111 (11) ◽

pp. 1021-1025 ◽

Cited By ~ 19

Author(s):

Cagatay Oysu ◽

Arif Ulubil ◽

Ismet Aslan ◽

Nermin Baserer

Keyword(s):

Hearing Loss ◽

Otoacoustic Emissions ◽

Significant Risk ◽

Neonatal Hyperbilirubinemia ◽

Neural Pathways ◽

Auditory Brain Stem Response ◽

Childhood Deafness ◽

Identifiable Risk Factor ◽

Auditory Brain Stem ◽

Severe Hyperbilirubinemia

Neonatal hyperbilirubinemia remains an important cause of childhood deafness, especially in developing countries. After neonatal hyperbilirubinemia, the auditory neural pathways, cochlea, or both may be affected. In this study, we aimed to determine the incidence of cochlear impairment and the appropriate means of hearing screening in hyperbilirubinemic neonates. A retrospective review of 1,032 pediatric patients with hearing loss revealed 67 cases (6.5%) of severe hyperbilirubinemia in the neonatal period. Thirty of these patients had neonatal hyperbilirubinemia as the single identifiable risk factor for hearing loss. In 26 of 30 cases (87%), otoacoustic emissions (OAEs) were absent, whereas in the remaining 4 cases (13%), robust emissions were detected despite an absent auditory brain stem response (ABR). Auditory screening of newborns with jaundice by OAEs possesses a significant risk of undiagnosed deafness. On the other hand, if the ABR is used as the single means of screening, auditory neuropathic conditions will probably be underlooked. Therefore, we recommend dual screening of hearing by ABR and OAEs in hyperbilirubinemic newborns.

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Comparison of distortion product otoacoustic emissions and pure tone audiometry in occupational screening for auditory deficit due to noise exposure

The Journal of Laryngology & Otology ◽

10.1017/s0022215115002790 ◽

2015 ◽

Vol 129 (12) ◽

pp. 1174-1181 ◽

Cited By ~ 4

Author(s):

N Wooles ◽

M Mulheran ◽

P Bray ◽

M Brewster ◽

A R Banerjee

Keyword(s):

Otoacoustic Emissions ◽

Pure Tone ◽

Noise Exposure ◽

Outer Hair Cell ◽

Cell Function ◽

Pure Tone Audiometry ◽

Otoacoustic Emission ◽

Distortion Product Otoacoustic Emissions ◽

Distortion Product Otoacoustic Emission ◽

Distortion Product

AbstractObjective:To examine whether distortion product otoacoustic emissions can serve as a replacement for pure tone audiometry in longitudinal screening for occupational noise exposure related auditory deficit.Methods:A retrospective review was conducted of pure tone audiometry and distortion product otoacoustic emission data obtained sequentially during mandatory screening of brickyard workers (n = 16). Individual pure tone audiometry thresholds were compared with distortion product otoacoustic emission amplitudes, and a correlation of these measurements was conducted.Results:Pure tone audiometry threshold elevation was identified in 13 out of 16 workers. When distortion product otoacoustic emission amplitudes were compared with pure tone audiometry thresholds at matched frequencies, no evidence of a robust relationship was apparent. Seven out of 16 workers had substantial distortion product otoacoustic emissions with elevated pure tone audiometry thresholds.Conclusion:No clinically relevant predictive relationship between distortion product otoacoustic emission amplitude and pure tone audiometry threshold was apparent. These results do not support the replacement of pure tone audiometry with distortion product otoacoustic emissions in screening. Distortion product otoacoustic emissions at frequencies associated with elevated pure tone audiometry thresholds are evidence of intact outer hair cell function, suggesting that sites distinct from these contribute to auditory deficit following ototrauma.

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Evaluation of outer hair cells function of non-operated ear after mastoid drilling using distortion-product otoacoustic emissions

The Journal of Medical Research ◽

10.31254/jmr.2019.5307 ◽

2019 ◽

Vol 5 (3) ◽

pp. 130-133

Author(s):

Virender Singh ◽

◽

BS Rakesh ◽

MB Bharathi ◽

Kota Harish Nag ◽

...

Keyword(s):

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Cell Function ◽

Outer Hair Cells ◽

Distortion Product Otoacoustic Emissions ◽

Mechanical Trauma ◽

Suppurative Otitis Media ◽

Distortion Product ◽

Study Materials ◽

And Gender

Aim: To analyze the effect of acoustic and mechanical trauma of drilling on the outer hair cell function of the non operated ear using distortion-product otoacoustic emissions (DPOAE’s) after mastoidectomy and its relation with the duration of drilling, age, and gender of the patient along with duration and permanency of the effects. Study Design: Observational study. Materials and Methods: Screening DPOAE’s were recorded preoperatively, immediate postoperative period, one hour postoperatively, 1st and 7th postoperative days in the normal ear in 94 patients who underwent tympanomastoidectomy for unilateral chronic suppurative otitis media (CSOM). DPOAE’s were measured using Neuro-audio-screener (Neurosoft Inc.) at 1.5 KHz, 2.1 KHz, 3.3 KHz, and 4.2 KHz. If DPOAE’s were absent preoperatively, the patients were not evaluated further and patients who had absent DPOAE’s post-operatively were successively followed till DPOAE’s were regained. Results: Of the 94 patients included, in 62 patients DPOAE’s were present preoperatively. Out of these 62, in 30 patients DPOAE’s were absent immediate postoperatively. On repeat testing, DPOAE’s were absent in 20 patients after 1 hour and in 8 patients after 1 day. On re-evaluation of these 8 patients after 1 week all of them had regained the DPOAE’s. In terms of duration of drilling, 66.6% patients in immediate post operative period, 90% patients in 1-hour post operative and 100 % patients on post operative day 1, having absent DPOAE’s had drilling time more than 60 minutes. Patients more than 30 years of age are affected more, but there is no preponderance for any gender. Conclusion: Nonoperated ear does have the effect of acoustic and mechanical trauma by vibration transmitted from another side during drilling of the operative ear mastoid bone. This effect is temporary and depends on the duration of drilling also.

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