Is cochlear implantation an effective treatment for Menière's disease?

OBJECTIVES: describe the results of a retrospective study of cochlear implantation (CI) in seven subjects with Menière's disease. METHODOLOGY: The subjects received either the Nucleus CI24RE(CA)/CI512 or the Advanced Bionics HiRes90K CI systems which use the ACE, MP3000, or HiRes S Fidelity 120 coding strategies. The audiometric measures included monosyllabic word lists (NVA) in quiet at 65 dB SPL and sentences in noise (LIST) at +10 dB SNR. The quality of life after implantation was assessed by means of the Nijmegen Cochlear Implant Questionnaire (NCIQ). RESULTS: After CI, the hearing of all subjects improved significantly (p < 0.001) as did their speech recognition (p = 0.018). Speech recognition in noise showed a mean improvement of 47%. The results were less clear for the treatment of vertigo associated with Menière's, as some patients continued to have vestibular attacks after implantation. On the NCIQ, subjects reported a mean quality of life after CI of 48.3%. CONCLUSIONS: This study clearly demonstrates that cochlear implantation is an adequate treatment of speech perception for subjects with Menière's disease who go on to develop bilateral severe to profound sensorineural hearing loss.

Evaluation of the rotatory vestibular test: exploration of stimulus parameters.

OBJECTIVES: The aim of this study was to construct a rotational test protocol after exploring the stimulus parameters of the rotatory vestibular test. METHODOLOGY: Twenty-four normal subjects were submitted to three different rotational paradigms: the sinusoidal harmonic acceleration test (SHAT), the pseudorandom rotation test (PRRT), and the velocity step test (VST). We investigated the influence of frequency and velocity on gain, phase and asymmetry values for the SHAT and the PRRT. In the case of the VST, we examined the influence of velocity and deceleration on gain, slow component velocity at deceleration, time constant, nystagmus preponderance, and time constant asymmetry. RESULTS: Frequency affected the SHAT response parameters, with significant phase differences between the frequencies 0.01, 0.02, 0.05, 0.1, and 0.2 Hz, while velocity, if kept below 150 degrees/s, had no influence on the results. In the case of the VST, responses were influenced by stimulus velocity and not by stimulus deceleration, with significantly higher gain values for the velocities 50 and 250 degrees/s. CONCLUSIONS: A velocity of 50 degrees/s tested at the frequencies 0.01, 0.02, 0.05, 0.1, and 0.2 Hz was suggested for the SHAT and PRRT protocol, whereas a velocity of 100 degrees/s with a deceleration of 200 degrees/s2 was preferred for the VST. The relevance of this rotational protocol has yet to be established from patient data.

Otologic disease in turner syndrome.

OBJECTIVE: This study involved the assessment of the otologic and audiologic characteristics of a group of patients with Turner syndrome. STUDY DESIGN: Prospective study consisting of a questionnaire (77 of 123 responders) and an otologic and audiologic evaluation in patients with Turner syndrome (41 participants). SETTING: Tertiary academic medical setting. PATIENTS: Children, adolescents, and adults with Turner syndrome (median age, 24 yr). INTERVENTIONS: Otomicroscopy, audiometry, immittance measurements, and diagnostic imaging. RESULTS: Otologic disease is an important characteristic in Turner syndrome. Sixty-six percent of the patients studied via the questionnaire reported a history of chronic or recurrent middle ear disease. Analysis of audiometric data in 40 patients tested reveals an equal amount of normal ears (38.8%) and pure sensorineural ears (38.8%), each constituting approximately one-third of the patient population. Pure conductive losses represent only one-fifth (21.3%) of auditory abnormality encountered. CONCLUSIONS: Careful follow-up during early childhood of children with Turner syndrome is necessary to detect middle ear disease and prevent sequelae. However, long-term periodic review is mandatory even after resolution of middle ear disease to detect sensorineural hearing loss.

Sensitive detection of noise-induced damage in human subjects using transiently evoked otoacoustic emissions.

Thirty-eight males (76 ears) exposed to occupational noise were investigated using transient-evoked otoacoustic emissions. Based upon the hearing loss at 4 kHz, they were classified into four described groups. Ten normally hearing subjects (20 ears) without exposure to occupational noise were used as controls. Significant changes in response amplitude, reproducibility, and signal to noise ratio (SNR) in broadband and frequency-bands (1, 2, 3, 4 kHz) were revealed between control subjects and the patients of group I exposed to noise with normal pure-tone audiometric thresholds. The changes of response amplitudes, reproducibility (%), and SNR were not significant between the group I and the patients of group II with mild hearing loss (< or = 40 dB) at 4 kHz. When the patients suffered from hearing loss beyond 40 dB HL at 4 kHz, emission amplitude, reproducibility, and SNR showed significant changes, whereas the percentage of absent emissions also showed significant changes. From these data, we conclude that TEOAE testing is more sensitive than pure-tone audiometry in the detection of early noise-induced damage. The test could be proposed as a hearing screen for monitoring employees with early noise-induced hearing loss.

Masking effects and tinnitus as explanatory variables in hearing disability.

In cases of substantial auditory handicap, the degree of pure-tone hearing loss or hearing loss for speech is seen as the primary determining factor. Sometimes the presence of tinnitus complaints and disproportionate masking effects of noise on speech reception are seen as aggravating factors. To investigate the relevance of tinnitus and masking effects in the context of hearing disability, four factorial designs with self-perceived hearing disability as the dependent variable were submitted to an analysis of variance. Impact of masking and tinnitus complaints were treated as independent variables with two levels and were each combined with a second independent variable to form a 2 x 2 fixed factor statistical model. This second independent variable was either hearing loss for pure tones (first and second model) or speech reception ability (third and fourth model). Both hearing loss for pure tones and speech reception capability were found to be significant explanatory factors for hearing disability. Impact of masking, if juxtaposed to average pure-tone hearing loss (first model), also came out of the analysis as a significant factor in hearing disability, whereas the tinnitus factor did not reach significance levels. No significant interactions between factors were found. The results support the idea of the differentiating audiogram-based disability estimates by taking noise susceptibility into account. The findings also suggest in an equivocal relation of tinnitus with hearing disability, which prevents it from being a straightforward disability predictor.

Multi-variant analysis of otoacoustic emissions and estimation of hearing thresholds: transient evoked otoacoustic emissions.

Evaluation of cochlear hearing loss by means of transiently evoked otoacoustic emissions is already established in clinical practice. However, accurate prediction of pure-tone thresholds is still questioned and is still regarded as troublesome. Both click- and tone-burst-evoked otoacoustic emissions at several intensity levels were measured and analysed in 157 ears from normally hearing and 432 ears from patients with different degrees of pure sensory hearing loss using the ILO88/92 equipment. Results of otoacoustic emissions (OAE), elicited by clicks and tone-bursts at centre frequencies from 1 to 5 kHz, were analysed using two different statistical methods. Both multivariate discriminant analysis and forward multiple regression analysis were used to determine which OAE variables were most discriminating and best at predicting hearing thresholds. We found that a limited set of variables obtained from both tone-burst and click measurements can accurately predict and categorize hearing loss levels up to a limit of 60 dB HL. We found correct classification scores of pure-tone thresholds between 500 and 4000 Hz up to 100 per cent when using combined click and tone-burst otoacoustic measurements. Prediction of pure-tone thresholds was correct with a maximum estimation error of 10 dB for audiometric octave frequencies between 500 and 4000 Hz. Measurements of multiple tone-bursts OAEs have a significant clinical advantage over the use of clicks alone for clinical applications, and a good classification and prediction of pure-tone thresholds with otoacoustic emissions is possible.

Mechanisms in noise-induced permanent hearing loss: an evoked otoacoustic emission and auditory brainstem response study.

In this study 22 patients (44 ears) with noise-induced permanent hearing loss were audiologically evaluated using transient-evoked otoacoustic emissions (TEOAE) and auditory brain-stem response (ABR). Twenty-one normal subjects (42 ears) without exposure to occupational noise were used as controls. Based upon the hearing loss at 4, 3, 2 and 1 kHz on the pure-tone audiogram, they were classified into four groups. In group 1 (eight ears), emissions were present in all ears but their TEOAE-noise level and their reproducibility (percentage) proved to be weak. The auditory brain-stem response (ABR) indicated that the I/V amplitude ratio, the latency values of wave V and the I-V intervals fell within the normal range in all ears. In Group 2 (14 ears), 40 per cent had no emissions, whereas the remaining ears showed weak emissions. The ABR revealed that in all ears the I/V amplitude ratio became small while wave V peak latency as well as I-V intervals were within the normal range. In Group 3 (10 ears), emissions were absent in 50 per cent, while in the other ears the emissions were very weak. The ABR revealed that the I/V amplitude ratio, which could be calculated in the 60 per cent in which wave I was present, was smaller than in Group 2. Wave V latency as well as I-V intervals were within the normal range. In Group 4 (12 ears), none of the ears showed emissions. The ABR indicated that the I/V amplitude ratio was much smaller when wave I was present (27 per cent) as well as I-V interval values being within the normal range. Wave V absolute latency value (delta V index) indicated a positive index in 17 per cent of this group (two ears) when wave I was absent. In the present study a dynamic process from cochlear outer hair cells to cochlear neurons was seen, correlating with an increasing hearing loss.

Choice of a tone-pip envelope for frequency-specific threshold evaluations by means of the middle-latency response: normally hearing subjects and slope of sensorineural hearing loss.

The effects of stimulus rise-fall and plateau times on the middle-latency response (MLR) waveform (Na-Pa amplitude and Pa latency) were investigated in 14 normally hearing subjects and an objective MLR threshold was evaluated at low and middle frequencies in ten normally hearing subjects and ten patients with slope of sensorineural hearing loss, using a selected stimulus-envelope time. After analyzing the effects of envelope times on the MLR waveform and the spectra of tone-pips, it was found that a rise-fall time of 4 ms with a plateau of 2 ms (4-2-4) is an acceptable compromise between a synchronous discharge and frequency specificity for estimating the MLR threshold. The MLR threshold produced by 4-2-4 tone-pips approximated the psychoacoustic threshold at low and middle frequencies in the normal and hearing impaired subjects. This demonstrates the clinical usefulness of the MLR in estimating low- and middle-frequency thresholds.

Audiovisual speech reception in noise and self-perceived hearing disability in sensorineural hearing loss.

Multiple regression analyses were performed on a corpus of data from 56 sensorineurally hearing-impaired subjects. In addition to tonal thresholds, the corpus included simple, quantitative self-ratings for disability and results from speech reception tasks in auditory-only, audiovisual, quiet and noisy conditions. The aim was to evaluate to what extent the predictive power of disability formulas based on the audiogram can be enhanced, when measures derived from speech reception tasks are added to tonal thresholds as supplementary predictors. The better-ear speech reception threshold proved to be a strong exclusive predictor: if speech reception thresholds were introduced into the prediction, the contribution of better-ear pure-tone averages became redundant. Speechreading ability always significantly enhanced the prediction's accuracy. Tonal thresholds or speech reception data combined with lipreading ability scores can explain considerable amounts (42 per cent and 54 per cent, respectively) of the variance in disability ratings. The conclusion is that auditory-only, audiogram-based prediction schemes must not be abandoned, but can be tailored to individuals on the basis of realistic audiovisual speech reception performance.

Bilateral threshold frequency weighting in hearing disability predictions.

Hearing disability can be measured by questionnaires, interviews or self-ratings. As these measurement techniques are not always appropriate for direct application in individual cases, particularly in the context of compensation claims, the assessment is sometimes reduced to a surrogate measure derived from audiometric thresholds. No final agreement emerges from correlation studies on hearing disability as to the optimal set of audiometric descriptors. However, a multiple regression equation, describing the relationship between audiometric data and numerically expressed self-ratings of disability, provides a means for predicting disability with relatively good precision, using some index derivable from the audiogram. The aim of the present study was to consolidate or amend current prediction schemes based on tonal audiometric data by investigating the problem of differential bilateral weighting of threshold frequency through multiple regression performed on experimental data coming from an unbiased group of hearing impaired subjects. In addition to tonal thresholds, this corpus included simple, quantitative self-ratings for disability. The sample was considered to be a representative cross-section of adult hearing impaired ENT patients. The results indicate that prevailing bilateral weightings are likely to overestimate the importance of the worse ear. The regression results did not incorporate the usual threshold values and frequency weightings. The outcome nevertheless offered a multiple correlation coefficient that was higher than most correlations reported in the literature between disability ratings and threshold values.

Distortion product otoacoustic emissions: a normative study.

Distortion product otoacoustic emissions (DPOAEs) were quite recently introduced as a new objective auditory screening technique, having a unique potential because of their ability to analyze the micromechanical functions of the cochlea in a frequency-specific way. In 1992, Kemp and Bray released the commercially available Otodynamics Analyzer ILO92, which enabled investigators and audiological centres to perform DPOAE measurements in different populations, but without any relationship to normative data. The purpose of this study was to describe the normative aspects of 2f1-f2 DPOAEs obtained with the ILO92 from 101 normal ears of 101 healthy young adults. The DPOAEs were obtained automatically by means of two data-collection protocols on the ILO92 in the form of DP-gram and DP-growth functions. These data were statistically processed to form a normative database which has the potential of serving as a basis of for further research aimed at determining the utility of DPOAE testing in evaluating ear pathology.

Middle-latency responses to assess objective thresholds in patients with noise-induced hearing losses and Ménière's disease.

In this study 23 patients with noise-induced hearing loss (NIHL) referred for medico-legal evaluation and a group of 18 cases with Ménière's disease were evaluated audiologically using the middle-latency response (MLR). Cross-correlation functions were used to assess precisely MLR thresholds in low and middle frequencies. Cross-correlation data obtained from suprathreshold levels to below threshold levels were compared with the normal limits of parameters found at threshold levels, allowing us to determine the true MLR threshold. Our results revealed that this MLR threshold and visual detection thresholds were different in 18% of both the NIHL and Ménière's disease groups. In this population the true MLR threshold was greater by 5 dB. These findings demonstrated that cross-correlation functions can enhance the sensitivity of the definition of the MLR threshold. True MLR thresholds were compared with subjective pure-tone audiometric (PTA) thresholds at the same frequencies (0.5, 1 and 2 kHz). The true MLR threshold and PTA threshold were in agreement within 10 dB in 91% of the NIHL group and all of the Ménière's disease group. The PTA threshold was greater by 15 dB or more in the remaining NIHL group. If a criterion of 15 dB discrepancy indicates non-organic hearing loss, it can be inferred that 9% of an NIHL population referred for medico-legal evaluation is exaggerating subjective audiometric thresholds.

Selecting the best tone-pip stimulus-envelope time for estimating an objective middle-latency response threshold for low- and middle-tone sensorineural hearing losses.

The effects of rise-fall and plateau times for the Pa component of the middle-latency response (MLR) were investigated in normally hearing subjects, and an objective MLR threshold was measured in patients with low- and middle-tone hearing losses, using a selected stimulus-envelope time. Our results showed that the stimulus-envelope time (the rise-fall time and plateau time groups) affected the Pa component of the MLR (quality was determined by the (chi 2-test and amplitude by the F-test). The 4-2-4 tone-pips produced good Pa quality by visual inspection. However, our data revealed no statistically significant Na-Pa amplitude differences between the two subgroups studied when comparing the 2- and 4-ms rise-fall times and the 0- and 2-ms plateau times. In contrast, Na-Pa became significantly smaller from the 4-ms to the 6-ms rise-fall time and from the 2-ms to the 4-ms plateau time (paired t-test). This result allowed us to select the 2- or 4-ms rise-fall time and the 0- or 2-ms plateau time without influencing amplitude. Analysis of the stimulus spectral characteristics demonstrated that a rise-fall time of at least 2ms could prevent spectral splatter and indicated that a stimulus with a 5-ms rise-fall time had a greater frequency-specificity than a stimulus of 2-ms rise-fall time. When considering the synchronous discharge and frequency-specificity of MLR, our findings show that a rise-fall time of four periods with a plateau of two periods is an acceptable compromise for estimating the objective MLR threshold.(ABSTRACT TRUNCATED AT 250 WORDS)

Application of cross-correlation function in the evaluation of objective MLR thresholds in the low and middle frequencies.

In this study, the cross-correlation function was applied in the evaluation of MLR thresholds in the low and middle frequencies. The parameters of the cross-correlation function consist of the correlation coefficient at a lag-time of zero (RO), the maximum correlation coefficient (RM), and the latency delay on the lag-time axis at the point of the maximum correlation coefficient (DL). The normal limits of the parameters of cross-correlation at the MLR threshold level, which was identified by visual detection across frequencies, were obtained in normal-hearing and hearing-impaired subjects. The cross-correlation functions for two traces were also performed below threshold level. All cross-correlation parameters (RO, RM and DL) below threshold level were outside normal limits in 91% of all the subjects. The incidence of the only RM or DL parameter value within normal limits was 6% or 3% of all cases at the subthreshold level. Correlation data allow precise measurements of the MLR threshold and enhance the sensitivity of the definition of the MLR threshold. In addition, our study provides quantifiable information for estimating MLR threshold.

Traumatic luxation of the stapes.

A case of traumatic middle and inner ear damage due to involuntary piercing of the tympanic membrane with a knitting needle is reported. The incudo-stapedial joint was dislocated and the intact stapes was depressed into the vestibule. Exploration of the middle ear, followed by extraction of the stapes, closure of the oval window with a vein graft and interposition of a prosthesis between the incus and oval window, improved the condition but did not restore inner ear function. A second case, of unclear etiology, is also presented. The indications, timing and technique of surgical intervention in cases of traumatic luxation of the stapes are briefly discussed.

[Important aspects of brain stem audiometry (BERA) with regard to the diagnosis of acoustic nerve neuroma]. / Belangrijke aspecten van de hersenstamaudiometrie (BERA) in verband met de diagnose van het acusticous-neurinoom.

Starting with a case report, the interest of the BERA for the diagnosis of acoustic tumor is examined. Moreover, factors being able to complicate a clear interpretation of the result (transmissional and sensorineural dysfunctions) are discussed. The conclusion is drawn that the E. Coch. G. offers a factor of greater precision in the use of the BERA as an oto-neurological diagnostic tool.