Evoked otoacoustic emissions behaviour in retinitis pigmentosa

Otolaryngology - Head and Neck Surgery, 1999

Journal of the Acoustical Society of America, 1991

This study aims to determine the impact of controlling cochlear-source mechanism on the accuracy with which auditory status is identified using otoacoustic emissions (OAEs) in two groups of subjects with normal hearing (NH) and subjects with mild to moderate hearing loss. Design: Data were collected from 212 subjects with NH and with mild to moderate hearing loss who fell into two categories based on a distortion product OAE (DPOAE) screening protocol: the uncertain-identification group (where errors were likely) and the certain-identification group (where errors were unlikely). DPOAE fine-structure patterns were recorded at intervals surrounding f 2 = 1, 2 and 4 kHz (f 2 /f 1 ratio = 1.22), with L 2 = 35, 45, and 55 dB SPL (L 1 /L 2 ratio = 10 dB). The discrete cosine transform was used to smooth fine structure, limiting the source contribution to the distortion source only. Reflection-source OAEs were also recorded using amplitude-modulated stimulus frequency OAEs (AM-SFOAE). Area under the relative operating characteristic (A ROC) curve was used to quantify test accuracy when the source contribution was controlled versus the condition where both sources contribute. Additionally, failure rate, fixed at 5% for NH ears, as a function of behavioral-threshold category was evaluated. Results: When data for the entire subject group were examined, reducing the reflection-source contribution to the DPOAE did not result in better test performance than the best control condition at any frequency tested. When the subjects with NH were restricted to those with confirmed fine structure, A ROC analyses indicated that reducing the reflection-source contribution resulted in several small increases in the accuracy (2%-5%) with which auditory status was identified relative to the best control condition. This improvement was observed for the lowest stimulus levels (i.e., L 2 = 35 or 45 dB SPL). In this subset of subjects, distortion-source DPOAEs resulted in more accurate identification of mild hearing loss for a fixed false-positive rate of 5% in NH ears at lower L 2 's, conditions with poor accuracy in the larger group of subjects. The impact of controlling the source contribution on the identification of moderate losses was less clear in the reduced subject group, with some conditions where the distortion-source DPOAE was more accurate than the control condition and other conditions where there was no change. There was no evidence that reflection-source AM-SFOAEs more accurately identified ears with hearing loss when compared to any of the DPOAE conditions in either the large or reduced group of subjects. Conclusion: While improvements in test accuracy were observed for some subjects and some conditions (e.g., mild hearing losses and low stimulus levels in the reduced subset of subjects), these results suggest that restricting cochlear source contribution by "smoothing" DPOAE fine structure is not expected to improve DPOAE test accuracy in a general population of subjects. Likewise, recording reflection-source OAEs using the AM-SFOAE technique would not be expected to more accurately identify hearing status compared to mixed-or single-source DPOAEs.

Brain and Development, 2000

Otoacoustic emissions (OAEs) were evaluated in 51 ears of 30 patients with a severe auditory brainstem response (ABR) waveform abnormality. Thirteen ears showed no ABR to click sound of higher intensity than 100 dBSPL (group 1). Fourteen ears exhibited only wave V or a decreased amplitude pattern of ABR (group 2). Twenty-four ears showed a predominant wave I or no wave III pattern (group 3). Almost all the ears with absent ABR showed no OAE, which strongly suggested hearing loss of cochlear origin, although one patient with alternating hemiplegia of childhood exhibited de®nite OAEs and auditory reactions without ABR. One patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) and her mother in group 2 had OAE abnormalities, which also suggested mild to severe hearing impairment. When OAEs are present, an accompanying ABR abnormality may be produced by brainstem dysfunction of the underlying disorder such as Pelizaeus±Merzbacher disease. There was a signi®cant relationship (x-square test P , 0:001) between the positivity of the distortion product OAE response and the clinical auditory reactions in 24 patients, although their ABR abnormalities did not re¯ect hearing impairment directly. Careful examination of both audiometry and OAEs might be necessary for further assessment of the hearing function in pediatric patients with neurological disorders and speci®c auditory nerve disease.

2009

Vi tiligo is a skin disease characterized by absence of melanin due to melanocytes destruction. Aim: to study the incidence of hearing alterations in patients with vitiligo. Method: prospective audiological evaluation, transientevoked otoacoustic emission recordings and study the effects of suppression in 24 patients with vitiligo. Their ages ranged from 15 to 45 years. Results: 21 patients (87.5%) had normal audiometry; 2 had unilateral hearing loss in the high frequencies and 1 had cochlear moderate hearing loss in the left ear. Of these 21 subjects, 66.7% had no otoacoustic emissions, suggesting cochlear dysfunction. Only 7 patients had otoacoustic emissions present in all frequencies (29.2%) and 17 (70.8%) did not have them, and the highest rate of no otoacoustic emissions happened in the right ear of males. Regarding the suppression study, 6 subjects failed, all of them were females, and their left ears were the most affected. Conclusion: the findings show that patients with vitiligo, particularly males, have a greater predisposition to cochlear dysfunction, especially in the right ear. As far as the suppression effect was concerned, there was a greater alteration in the female efferent system, particularly in the left ear. Hearing alterations did not vary as far as age is concerned, type of vitiligo and time of disease progression.

Acoustic Emission - Research and Applications, 2013

Medical science monitor : international medical journal of experimental and clinical research, 2012

The aim of this study was to investigate the effects of sub-clinical alterations on the amplitudes and slopes of the DPOAE input-output responses from subjects with previous history of middle ear dysfunction. The study included 15 subjects with and 15 subjects without a history of otitis media in the last 10 years. All participants were assessed with acoustic immittance, pure-tone audiometry, and DPOAEs. For the later, I/O functions and I/O slopes were estimated at 1501, 2002, 3174, 4004 and 6384 Hz. No statistically significant differences were found between the 2 groups in terms of behavioral thresholds. The group with a previous history of middle ear dysfunction presented significantly lower mean DPOAE amplitudes at 2002, 3174 and 4004 Hz. In terms of DPOAE slopes, no statistically significant differences were observed at the tested frequencies, except at 3174 Hz. Middle ear pathologies can produce subclinical alterations that are undetectable with traditional pure-tone audiometr...

The Annals of otology, rhinology, and laryngology

Hearing Research, 2001

The aim of this study was to investigate the possible role of cochlear outer hair cell function with TEOAE and DPOAE tests in patients with normal hearing and tinnitus. 25 tinnitus patients with normal hearing sensitivity selected as study group. Control group consist of 50 normal hearing subjects without tinnitus. All subjects had thresholds below 25 dBHL at frequencies 250-8,000 Hz, tympanogram type A and normal acoustic reflex thresholds. TEOAE were recorded with click stimulus at 80 dB SPL at 1,000, 2,000, 3,000 and 4000 Hz. DPOAE were measured at frequencies 1,000-8,000 Hz and intensity of L1 55 dB SPL and L2 65 dB SPL. Amplitude of DPOAE and TEOAE were decreased in all frequencies in study group. There was significant difference regarding prevalence abnormal TEOAE and DPOAE between study group and control group. There was relationship between dysfunction of outer hair cells and tinnitus in subjects with normal hearing.

2019

American Journal of Otolaryngology, 1998

To investigate the activities of inner ear melanin in patients with pigment variations and disorders. Our purpose was to find evidence on the effects of melanin-containing cells by measuring the high-frequency threshold and the latency of stapes reflex in patients with vitiligo. Twenty-nine patients with active vitiligo and 41 healthy subjects were included in this study. Pure tone thresholds were determined at frequencies between 250 and 16,000 Hz. Ipsilateral and contralateral stapes reflexes were measured at 1,000, 2,000, and 4,000 Hz. After we compared the results in the control and vitiligo groups by using the Mann-Whitney U test for each frequency, we compared women and men separately to eliminate gender differences. Pure tone thresholds of the vitiligo group were significantly lower than the control group at 4,000, 6,000, 8,000 and 10,000 Hz (P < .05). The statistically different thresholds were 8,000 and 10,000 Hz in women, compared with 4,000, 6,000, 8,000, 10,000, 12,500, and 16,000 Hz in men (P < 0.05). Reflex latencies for the two groups were not statistically different. Vitiligo, which is a type of pigment disorder, seems to be an effective factor in hearing loss, and men are more susceptible to it than women. The mechanism for this condition might be the absence of the preventive function of melanin-containing cells in the inner ear.