耳声发射正常的听觉障碍类型

目的：分析总结临床中耳声发射正常的听觉障碍类型。方法：对83例听觉障碍患者行纯音听阈、阻抗、听性脑干反应（ABR）、40Hz AERP、自发性耳声发射（SOAE）、瞬态耳声发射（TEOAE）、畸变产物耳声发射（DPOAE）测试及CT和（或）MRI扫描。结果：耳声发射（OAE）正常的听觉障碍包括：①听神经病68例;②听神经瘤2例;③皮层聋或中枢性聋3例;④听觉过敏2例;⑤功能性聋2例;⑥伪聋6例。结论：耳声发射检测在蜗后性聋、中枢性聋、非器质性聋和其他一些特殊类型听觉障碍的诊断和鉴别诊断中具有重要临床意义。     

单侧听神经病附三例报告

目的　探讨单侧听神经病的听功能特征及病损部位。方法　报告及分析 3例患者的临床资料、纯音测听、声导抗测试、畸变产物耳声发射 (DPOAE)、听性脑干反应 (ABR)检测结果。结果　 3例单侧患耳纯音听力图分别为上升型、平坦型及下降型 ,听力损失 1例为中度 ,2例为重度 ,另侧听力图正常 ;3例患者双侧DPOAE正常引出 ,而ABR患侧未能引出 ,健侧正常引出。颞骨HRCT未见异常。结论　单侧听神经病的听功能特征与双侧听神经病的听功能特征相同。诱发性耳声发射及ABR对鉴别一般感音神经性聋与中枢性聋有重要意义。病损部位可能在内毛细胞至听神经的传入通路     

Otorhinolaryngological studies in diabetics

A total of 50 patients with diabetes mellitus were the subject matter of this study. Of these, 13 patients had diabetic neuropathy on clinical evaluation. Amongst the group of patients without diabetic neuropathy, 64.86% had sensorineural hearing loss and 21.6% patients had conductive deafness as compared to patients with diabetic neuropathy having sensorineural hearing loss in 69.2% and conductive deafness in 23% cases. The hearing threshold were found to be within normal limits in deabetics with or without neuropathy at lower frequencies but it was significantly incressed at higher frequencies (4000 Hz and 8000 Hz) in patients with diabetic neuropathy when compared with diabetic patients without neuropathy. The hearing threshold were increased at higher frequencies in uncontrolled diabetics. This was significant when compared with diabetics with normal fasting plasma glucose. The values of these tests as diagnostic and prognostic tools presently remains of no avail. However, it is hoped that with better precision and sophistication they may be utilised to detect finer sensorineural loss in diabetics, much before the development of long term complication inflicting the nervous system. This study also underlies the importance of looking for the hearing defects in diabetics which may be insignificant to the patient in face of apprehension for the disease itself.     

Suppression of evoked otoacoustic emissions by contralateral noise exposure in humans

The effects of contralateral noise exposure on evoked otoacoustic emission (e-OAE) were investigated in 10 normal hearing subjects and 3 cases with unilateral deafness. The e-OAE was recorded by ILO88 and weighting noise was given to the contralateral ear (impaired side in unilateral deafness cases). The air conducted noise exposure showed suppressive effect on e-OAE along with the increase of noise stimulus intensity in normal hearing subjects, but did not in unilateral deafness cases. The degree of suppression in e-OAE was most remarkable in highest peak power between 1 kHz and 2 kHz in FFT picture and the mean value of maximal suppression in 10 normal hearing subjects was 2.2 dB. The bone conducted noise exposure showed no effects on e-OAE in either normal hearing subjects or unilateral deafness cases. It was suggested that the contralateral noise exposure could suppress the function of cochlear micromechanics probably via crossed olivocochlear bundle.     

Audiologische Ergebnisse mit Cochlear implant bei einseitiger Taubheit

Introduction

Single-sided deafness has a strong impact on quality of life. Besides the difficulties in sound localization, patients also require increased effort to hear. The latter makes it difficult to follow conversations for an extended period, leading to social isolation. Cochlear implantation (CI) represents a possible treatment option for deafness in one ear.

Methods

In the present study, 13 patients with unilateral deafness where treated with CI. All patients were examined by pure tone audiometry and speech tests (Freiburger; HSM; OlSa), as well as sound localisations tests. The single-sided deaf situation is compared to CI-aided binaural hearing.

Results

At 100%, the acceptance rate was very high. The two different auditory inputs were well integrated. Patients reported satisfactory restoration of acoustic orientation and sound localization as well as great ease of listening in noisy surroundings. There was no negative impact on the normal hearing side.

Conclusion

These prelimary results confirm the effectiveness of CI treatment in unilateral deafness.     

儿童单侧听神经病附三例分析

目的 探讨儿童单侧听神经病的听力学特征。方法 对3例单侧听神经病患儿进行纯音听阈(PTT)、声反射(AR)、听性脑干反应(ABR)和畸变产物耳声发射(DPOAE)检查，并对其结果进行综合分析。结果 3例患儿的PTT均呈1侧耳听力正常，另1侧耳听力丧失。健耳的同侧和交叉AR能引出，患耳的同侧和交叉AR未能引出。健耳的ABR各波潜伏期正常，患耳的ABR各波未能引出。双耳DPOAE各频率反应幅值正常。结论：DPOAE正常或基本正常，PTT、AR和ABR异常是听神经病的重要特征。单侧听神经病的听力学特征与双侧听神经病基本一致。对儿童表现为单侧感音神经性聋者宜进行系统的听力学检查，以期作出正确的诊断。     

Clinical and radiological findings in subjects with unilateral Ménière's disorder

In order to contribute to the knowledge of the possible causes of Ménière's disorder, the authors have conducted systematic studies based on blood analysis and on petrous bone radiological examinations in patients suffering from unilateral Ménière's disorder and in two control groups, one of patients with unilateral sudden sensorineural deafness and the other one of normally hearing subjects suffering from neurological diseases. Blood tests have revealed systemic disorders (dyslipidosis, hypoglycaemia, hyperglicaemia, hypothyroidism, lues) in 49%, 48% and in 50% of the subjects respectively with Ménière's disorder, with sudden deafness, and with normal hearing. As to the radiological study, changes of the temporal bone (absence or small cells pneumatization and/or absence or narrowing of the vestibular aqueduct) were found in 78% of ears with Ménière's disorder, in 34% of ears with sudden deafness and in 46% of normal ears.     

Einseitige Schwerhörigkeit und Kunstkopftechnik

Summary Ten subjects with unilateral hearing impairment or deafness and 14 with normal bilateral audition listened with headphones to stereophonic tape recordings that had been produced, on the one hand, with the aid of a dummy head and, on the other, by a non-head-related stereophonic technique. For subjects with unilateral hearing impairment or deafness, the dummy head technique yielded a significantly better speech recognition from various directions with simultaneous background noise. No improvement was evident in subjects with normal hearing.     

Diverse etiologies manifesting auditory neuropathy characteristics from infants with profound hearing loss and clinical implications

ObjectiveAuditory neuropathy spectrum disorder (ANSD) is a hearing disorder with impaired signal transmission from the inner ear to the brain. The electrophysiological characteristics of auditory neuropathy (AN characteristics) are marked with presence of otoacoustic emissions (OAE) or cochlear microphonics (CM) in the absence of auditory brainstem response (ABR). This study aimed to review etiologies related to AN characteristics from infants with profound hearing loss (HL), either unilaterally or bilaterally.Study designProspective cohort study for thirty infants with prelingual profound HL.MethodsABR, OAE, and/or CM were analyzed to identify electrophysiological characteristics. Temporal bone computed tomography and/or internal acoustic canal magnetic resonance imaging were reviewed to identify anatomical abnormalities. The electrophysiological characteristics and cochlear nerve status were analyzed according to the laterality of deafness (unilateral vs bilateral).ResultsAmong the total 41 ears (from 30 infants) with profound HL, 13 ears (7 (36.8%) of 19 ears with unilateral HL and 6 (27.3%) of 22 ears associated with bilateral HL) showed AN characteristics (37.1%), and 21 ears showed cochlear nerve deficiency (CND) (51.2%). AN characteristics was detected about two times more frequently in cases with CND (38.1%) than with anatomically normal cochlear nerve (20.0%), the difference not reaching a statistical significance probably due to a small sample size. Detection of AN characteristics did not differ between unilateral and bilateral profound HL, even though presence of CND was more frequently detected in cases with unilateral profound HL than with bilateral cases. There were at least five types of etiologies related to AN characteristics in 13 ears (from 10 infants) in our series depending on the laterality of deafness and presence of CND.ConclusionsThis study demonstrates that there were diverse etiologies related to AN characteristics from infants with unilateral or bilateral profound HL. Association between CND and AN characteristics is suggestive but not solid at this moment and AN characteristics is not a fully penetrant feature of CND.     

Einseitige Taubheit — Neuropsychologische Untersuchungen

Summary Forty righthanded persons with unilateral deafness-congenital or acquired in the first years of their life — underwent in average 25 years later a neuro-psychological examination. The main purpose was to investigate if the missing auditory input to the contralateral hemisphere caused changes in hemispheric specialization, memory and so-called intelligence. Ten women were deaf on the left side, 10 on the right side, and 10 men were deaf on the left side and 10 on the right side. Especially man with deafness on the right side scores poorer results in the tests than the other three groups. Half of the persons indepently of sex and side of deafness showed impaired memory function. The intelligence was found inside the normal material.     

Self reported hearing difficulties following excision of vestibular schwannoma

A new questionnaire, developed to investigate self-reported hearing difficulties in unilateral deafness, was completed by 221 post-surgical vestibular schwannoma patients. Results were compared to a group of 51 normal hearers and 12 patients with severe unilateral deafness from other causes. The vestibular schwannoma patients rated their post surgical hearing as profoundly deaf in the operated ear, and worse than pre-surgical in the other. Factor analysis of the results revealed a general hearing factor and five factors, indirect listening, direct listening, face-to-face listening, noise and distance, and localization, representing performance in specific listening situations. Two factors, direct listening and face-to-face listening have not been commented upon previously in the literature. No differences were found between the hearing-impaired groups on any of the factors. Both groups gave ratings significantly worse than the normal hearers on all factors, and rated themselves worst on indirect listening, in which speech comes from the impaired side. It was concluded that severe unilateral deafness is a significant disability, requiring more attention in clinical practice, particularly with pre-surgical vestibular schwannoma patients.     

Self reported hearing difficulties following excision of vestibular schwannoma

A new questionnaire, developed to investigate self-reported hearing difficulties in unilateral deafness, was completed by 221 post-surgical vestibular schwannoma patients. Results were compared to a group of 51 normal hearers and 12 patients with severe unilateral deafness from other causes. The vestibular schwannoma patients rated their post surgical hearing as profoundly deaf in the operated ear, and worse than pre-surgical in the other. Factor analysis of the results revealed a general hearing factor and five factors, indirect listening, direct listening, face-to-face listening, noise and distance, and localization, representing performance in specific listening situations. Two factors, direct listening and face-to-face listening have not been commented upon previously in the literature. No differences were found between the hearing-impaired groups on any of the factors. Both groups gave ratings significantly worse than the normal hearers on all factors, and rated themselves worst on indirect listening, in which speech comes from the impaired side. It was concluded that severe unilateral deafness is a significant disability, requiring more attention in clinical practice, particularly with pre-surgical vestibular schwannoma patients.     

Auditory neuropathy in childhood

Objectives: Auditory neuropathy is a recently described disorder in which patients demonstrate hearing loss for pure tones, impaired word discrimination out of proportion to pure tone loss, absent or abnormal auditory brainstem responses, and normal outer hair cell function as measured by otoacoustic emissions and cochlear microphonics. We have identified eight pediatric patients having hearing deficits that are most likely due to a neuropathy of the eighth nerve. In this study, the results of audiologic testing performed with these eight children are described. Study Design: Retrospective review of audiologic findings in eight children with auditory neuropathy. Methods. Each subject was tested with pure tone and speech audiologic testing, auditory brainstem response, and click-evoked otoacoustic emissions. Results of these tests were tabulated and summarized. Results: Pure tone audiologic testing revealed five children with upsloping sensorineural hearing loss, two with high frequency loss, and one with a mild, flat configuration. Six children demonstrated poor word discrimination scores, and the other two had fair to good word discrimination. All eight subjects had normal distortion product and transient otoacoustic emissions. All eight children demonstrated absent or marked abnormalities of brainstem auditory evoked potentials. These findings suggest that while cochlear outer hair cell function is normal, the lesion is located at the eighth nerve. Conclusions: Recent advances in otoacoustic emissions testing permit differentiation of neural deafness from sensory deafness. This paper describes the clinical presentation and audiologic findings in pediatric auditory neuropathy, as well as the recommended management of these patients. Otolaryngologists should be aware of this disorder and implications for its management, which differs from treatment of sensorineural hearing loss. Key Words: Auditory neuropathy, childhood, hearing loss, auditory brainstem response, evoked otoacoustic emissions.     

Duration of unilateral auditory deprivation is associated with reduced speech perception after cochlear implantation: A single-sided deafness study

Objective: Examine the relationship between duration of unilateral deafness and speech perception outcomes after cochlear implantation in adults with single-sided deafness.

Methods: A systematic review of PubMed articles containing individual speech perception and duration of deafness data from single-sided deaf adults. Studies were selected for detailed review and duration of deafness and speech perception outcomes were extracted, with speech scores reported as percent correct. A linear regression as a function of study and length of deafness was performed.

Results: A statistically significant negative effect of duration of unilateral deafness on speech perception was found, but there was substantial uncertainty regarding the strength of the effect.

Discussion: Existing data make it difficult to either support or reject a hard 5- or 10-year unilateral auditory deprivation limit on cochlear implant (CI) candidacy for patients with single-sided deafness. This is because the totality of available data are consistent with a very small effect, perhaps negligible in practical terms, and just as consistent with a very large effect. Regardless of effect size, the present results have important basic implications. They suggest that unilateral sound deprivation may have a deleterious effect on auditory processing even though more central parts of the auditory system have continued to receive input from a contralateral normal ear.

Conclusions: Speech perception scores in SSD patients are negatively correlated with duration of deafness, but the limited amount of data from cochlear implant users with long-term single-sided deafness leads to substantial uncertainly, which in turn precludes any strong clinical recommendations. Further study of SSD CI users with long-term deafness will be necessary to generate evidence-based guidelines for implantation criteria in this population.     

Imaging in sensorineural deafness

In this paper, the authors describe, in details, the techniques and the indication of CT scanner and MRI for the evaluation of neurosensory deafness. CT scanner allows to study bony and pneumatized structures of the ear. CT scanner is mostly indicated for the study of congenital deafness, post-trauma deafness and unilateral progressive deafness for which the otoscopy is normal. MRI allows the study of fluid compartments, nerves, vascularization and tissue. MRI will be chosen to evaluate sudden sensory neural deafness and unilateral deafness. However, it is worth to mention that CT scanner and MRI are complementary and that precision of the imaging system as well as a strong collaboration between the otolaryngologist and the radiologist are mandatory.     

Amplification in the rehabilitation of unilateral deafness: speech in noise and directional hearing effects with bone-anchored hearing and contralateral routing of signal amplification.

OBJECTIVE: Vibromechanical stimulation with a semi-implantable bone conductor (Entific BAHA device) overcomes some of the head-shadow effects in unilateral deafness. What specific rehabilitative benefits are observed when the functional ear exhibits normal hearing versus moderate sensorineural hearing loss (SNHL)? DESIGN: The authors conducted a prospective trial of subjects with unilateral deafness in a tertiary care center. PATIENTS: This study comprised adults with unilateral deafness (pure-tone average [PTA] > 90 dB; Sp.D. < 20%) and either normal monaural hearing (n = 18) or moderate SNHL (PTA = 25-50 dB: Sp.D. > 75%) in the contralateral functional ear (n = 5). INTERVENTIONS: Subjects were fit with contralateral routing of signal (CROS) devices for 1 month and tested before (mastoid) implantation, fitting, and testing with a bone-anchored hearing aid (BAHA). OUTCOME MEASURES: Outcome measures were: 1) subjective benefit; 2) source localization tests (Source Azimuth Identification in Noise Test [SAINT]); 3) speech discrimination in quiet and in noise assessed with Hearing In Noise Test (HINT) protocols. RESULTS: There was consistent satisfaction with BAHA amplification and poor acceptance of CROS amplification. General directional hearing decreased with CROS use and was unchanged by BAHA and directional microphone aids. Relative to baseline and CROS, BAHA produced significantly better speech recognition in noise. Twenty-two of 23 subjects followed up in this study continue to use their BAHA device over an average follow-up period of 30.24 months (range, 51-12 months). CONCLUSION: BAHA amplification on the side of a deaf ear yields greater benefit in subjects with monaural hearing than does CROS amplification. Advantages likely related to averting the interference of speech signals delivered to the better ear, as occurs with conventional CROS amplification, while alleviating the negative head-shadow effects of unilateral deafness. The advantages of head-shadow reduction in enhancing speech recognition with noise in the hearing ear outweigh disadvantages inherent in head-shadow reduction that can occur by introducing noise from the deaf side. The level of hearing impairment correlates with incremental benefit provided by the BAHA. Patients with a moderate SNHL in the functioning ear perceived greater increments in benefit, especially in background noise, and demonstrated greater improvements in speech understanding with BAHA amplification.     

The promontory test and electrocochleography in deafness caused by mumps

Contradictory histological findings in patients with deafness following mumps led us to conduct electrophysiological investigations. Promontory testing (PT) and measurement of cochlear microphonics (CM) enabled us to distinguish between neural and sensory deafness. On the basis of a careful history and serological tests in 19 cases of unilateral deafness we found that the hearing loss was probably caused by mumps. In all patients except one auditory sensations could be obtained by electric stimulation of the acoustic nerve whereas no CM were detectable even with strong stimuli of 100 dB tonepips. In view of the electrophysiological findings, doubt is cast on the neural genesis of deafness following mumps as assumed by Lehnhardt (1962).     

Evoked otoacoustic emissions in sensorineural hearing impairment: its clinical implications

This study was performed for the purpose of determining whether or not evoked otoacoustic emissions are useful as a clinical test. Two hundred and twenty-six sequences of the emission in response to stimulus tone bursts were averaged. The detection threshold of the emission was elevated in ears of inner ear impairment with profound sensorineural hearing loss, such as inner ear anomaly, mumps deafness, or sudden deafness, but it was not observed in ears of functional deafness. The mean interaural differences of emission threshold were near 35 dB in unilateral inner ear impairments with profound hearing loss. There was a positive correlation between the interaural difference of audiometric threshold and that of emission threshold in sudden deafness ears with various degrees of hearing loss. The incidence of continuous emission, whose duration was longer than 6 msec, was 30% in normal hearing ears and it was close to 90% in ears with bilateral or unilateral dip type hearing loss. The result was verified in a survey of a junior high school brass band. The conclusion is that there is clinical usefulness for the evoked otoacoustic emissions in evaluating cochlear function and in predicting noise susceptibility.     

Sudden hearing loss in sarcoidosis: otoneurological study and neuroradiological correlates

Sarcoidosis is an inflammatory multisystem disorder of unknown cause. Approximately 5-7% of patients manifest symptoms of central nervous system involvement, or neurosarcoidosis. Cranial neuropathy usually entails facial nerve palsy and optic neuritis. Sudden hearing loss has been reported in fewer than 20 cases. Herewith, two new cases of sudden hearing loss due to probable neurosarcoidosis are reported, each having a quite different clinical course. In one case, unilateral sudden hearing loss and facial palsy were the presenting symptoms of systemic sarcoidosis, while in the second, unilateral sudden deafness occurred despite ongoing immunosuppressive treatment for systemic sarcoidosis.     

Asymmetry of temporal processing in listeners with normal hearing and unilaterally deaf subjects

OBJECTIVES: In general, auditory cortex on the left side of the brain is specialized for processing of acoustic stimuli with complex temporal structure including speech, and the right hemisphere is primary for spectral processing and favors tonal stimuli and music. This asymmetry in processing is further emphasized when hemisphere-favored stimuli are presented to the contralateral ear. The purpose of the first experiment is to further investigate the properties that dictate lateralized processing of auditory stimuli by ear and the relationship between auditory task and stimulus type. Next, it is not clear what compensation may exist for the loss of function of one ear and consequently, reduced access to functions primary performed in the opposite hemisphere, in the case of early unilateral profound hearing loss. The purpose of experiment 2 is to determine if any compensation for loss of function is seen in persons with early unilateral deafness. DESIGN: Experiment 1: Gap detection thresholds were determined in 30 right-handed listeners with normal hearing using wide-band noise markers (temporally complex), 400 and 4000 Hz pure tones presented individually to the left and right ears. Experiment 2: The same procedure was administered to listeners with early-onset, severe-to-profound unilateral deafness (seven left ear deaf and five right ear deaf) in the hearing ear alone. RESULTS: A significant right ear advantage was found for gap detection threshold using noise markers and a smaller left ear advantage was found for tonal stimuli. Listeners with unilateral deafness demonstrated that the hearing ear, left or right, performed in a manner similar to listeners with normal hearing. CONCLUSIONS: Results indicate that (1) gap marker, more than task, was the salient feature in determining laterality of processing in this experiment, (2) the two ears have distinct processing capacity based on stimulus type, and (3) compensation for loss is not apparent in persons with congenital unilateral deafness.