听神经病伴发前庭下神经损害

目的 通过检测13例听神经病患者的前庭诱发的肌源性电位(vestibular evokedmyogenic potentials,VEMPs),了解听神经病患者是否同时伴发前庭下神经损害,探讨前庭下神经损害与听神经病的关系。方法 记录13例听神经病患者VEMPs,观察VEMPs表现形式;分析病程、低频听阈及言语识别率与VEMPs的关系。结果 13例听神经病患者中有7例存在VEMPs异常,占54％。异常的表现形式为VEMPs低振幅和VEMPs不能引出。正常VEMPs与异常VEMPs在低频听力损失、病程和言语识别率3个方面差异无显著性(P>0.05)。结论 部分听神经病患者伴发前庭下神经功能异常,说明两者病变可以同时并存;听神经病患者的病变程度方面与VEMPs无明显直接相关性,说明听神经病与前庭下神经损害两者之间又具有相对独立性。     

Sacculo-collic pathway dysfunction accompanying auditory neuropathy

CONCLUSIONS: In a patient with bilateral auditory neuropathy (AN), the vestibular-evoked myogenic potential (VEMP) was probably absent because of a neuropathy involving the inferior vestibular nerve and/or its end organ, the saccule. Our result can therefore be interpreted as a concomitant unilateral sacculo-collic neuropathy. We suggest the use of more precise terms to characterize AN patients with involvement of different parts of the inner ear and its innervations. We encourage detailed vestibular assessment in patients with AN in order to assess the co-existence of any symptomatic or asymptomatic vestibular disorder. Information such as that provided in this report will be valuable for clinicians caring for this group of patients. OBJECTIVE: AN is a disorder characterized by the absence or severe impairment of auditory brainstem responses in the presence of normal cochlear outer hair cell function as revealed by otoacoustic emissions (OAEs) and/or electrocochleography (ECoG). A variety of processes and etiologies are thought to be involved in its pathophysiology. In most literature reports the auditory profile of patients with AN is discussed. However, the extent of vestibular involvement, especially that involving the saccule, is not known. We performed vestibular tests to assess the status of the saccule in a patient with AN. MATERIAL AND METHODS: One patient with AN was studied. The patient was a right-handed 21-year-old female with chief complaints of hearing loss and speech perception difficulty. RESULTS: The auditory test results were consistent with the diagnosis of AN, i.e. absent auditory brainstem responses, moderate hearing loss, an inappropriately profound speech discrimination score and the presence of OAEs and measurable cochlear microphonics on ECoG. On neurological examination, gait and balance tests were normal. Ice-water caloric testing induced a sensation of dizziness in both ears. Short tone-burst VEMPs showed no response on left-ear stimulation and a biphasic response with normal latency and amplitude on right-ear stimulation.     

Influence of aging over 10 years on auditory and vestibular functions in three patients with auditory neuropathy

The influence of aging on hearing and vestibular function in patients with auditory neuropathy has not been investigated. The purpose of this study was to investigate how hearing and vestibular function in this disease change with aging. The subjects were three female patients with auditory neuropathy. We checked their hearing and vestibular function by speech discrimination tests, ABR, ECochG, DPOAE, caloric test, damped-rotational chair test, and VEMPs. In all three patients, speech discrimination ability and vestibular function markedly declined with aging. However, speech language understanding and higher brain function were less affected by aging.     

Sacculo-collic pathway dysfunction accompanying auditory neuropathy

Conclusions. In a patient with bilateral auditory neuropathy (AN), the vestibular-evoked myogenic potential (VEMP) was probably absent because of a neuropathy involving the inferior vestibular nerve and/or its end organ, the saccule. Our result can therefore be interpreted as a concomitant unilateral sacculo-collic neuropathy. We suggest the use of more precise terms to characterize AN patients with involvement of different parts of the inner ear and its innervations. We encourage detailed vestibular assessment in patients with AN in order to assess the co-existence of any symptomatic or asymptomatic vestibular disorder. Information such as that provided in this report will be valuable for clinicians caring for this group of patients. Objective. AN is a disorder characterized by the absence or severe impairment of auditory brainstem responses in the presence of normal cochlear outer hair cell function as revealed by otoacoustic emissions (OAEs) and/or electrocochleography (ECoG). A variety of processes and etiologies are thought to be involved in its pathophysiology. In most literature reports the auditory profile of patients with AN is discussed. However, the extent of vestibular involvement, especially that involving the saccule, is not known. We performed vestibular tests to assess the status of the saccule in a patient with AN. Material and methods. One patient with AN was studied. The patient was a right-handed 21-year-old female with chief complaints of hearing loss and speech perception difficulty. Results. The auditory test results were consistent with the diagnosis of AN, i.e. absent auditory brainstem responses, moderate hearing loss, an inappropriately profound speech discrimination score and the presence of OAEs and measurable cochlear microphonics on ECoG. On neurological examination, gait and balance tests were normal. Ice-water caloric testing induced a sensation of dizziness in both ears. Short tone-burst VEMPs showed no response on left-ear stimulation and a biphasic response with normal latency and amplitude on right-ear stimulation.     

听神经病的临床与听功能特征

目的:探讨听神经病的临床与听功能特征。方法:总结分析54例听神经病患者的临床资料、听力学测试及电生理检查情况。结果:纯音听力图呈上升型70耳,覆盆型25耳,平坦型5耳,下降型4耳;低频、中频及高频平均阈值为(67.63±15.30,43.61±16.28,32.25±14.80)dB HL。声导抗鼓室图全部正常,77耳镫骨肌声反射消失,31耳声反射阈部分增高。听性脑干反应(ABR)全部未引出。畸变产物耳声发射(DPOAE)正常引出,26例行对侧声抑制未受影响。16例言语识别率差,与纯音听阈不成比例。23例颞骨CT或MRI未见异常。10例伴有周围神经病。结论:ABR自波Ⅰ起缺失而DPOAE正常引出,言语分辨力差与纯音听阈不成比例,镫骨肌声反射及OAE交叉抑制异常,纯音听力图多呈上升型以低频损失为主,是听神经病听功能的重要特征。提示病损主要位于耳蜗内听神经纤维。应与一般的感音神经性聋和中枢性聋相鉴别。     

Speech perception in children with auditory neuropathy/dyssynchrony managed with either hearing AIDS or cochlear implants

OBJECTIVE: To evaluate speech perception skills in children with auditory neuropathy (AN)/auditory dyssynchrony (AD)-type hearing loss managed with either hearing aids or cochlear implants. STUDY DESIGN: Prospective data collection in 3 subject groups: AN/AD children fitted with bilateral amplification, AN/AD children fitted with cochlear implant (in 1 or both ears), and a matched control group of implanted children with sensorineural hearing loss. MAIN OUTCOME MEASURE: Open-set monosyllabic words (consonant-nucleus-consonant). RESULTS: Of the 10 implanted AN/AD children, 9 demonstrated significant speech discrimination (consonant-nucleus-consonant phoneme score > or =55%). Similar results were obtained for the aided AN/AD group. Findings for both AN/AD subject groups were poorer than those of the implanted sensorineural cohort. CONCLUSION: Cochlear implantation can offer useful hearing in subjects with AN/AD-type hearing loss. However, expectations for this group may need to be lower than for patients with peripheral (cochlear) loss.     

Involvement of peripheral vestibular nerve in individuals with auditory neuropathy

The vestibulocochlear nerve is a sensory nerve that serves the organs of hearing and equilibrium. Neuropathies of the nerve, particularly auditory neuropathy may be caused by primary demyelination or by axonal diseases. In disorders affecting the cochlear nerve, it is probable that the vestibular nerve is involved as well. There are isolated reports of the involvement of the inferior vestibular nerve (using vestibular-evoked myogenic potentials) in individuals with AN. However, there is a dearth of information on the involvement of the superior vestibular nerve and other functions such as optokinetic, saccade and vestibulo-occular reflex. A total of three subjects diagnosed as having auditory neuropathy, underwent an extensive vestibular assessment consisting of clinical tests of stability (Romberg, Fukuda stepping test), administration of dizziness questionnaire developed by Maryland hearing and balance centre, cervical vestibular-evoked myogenic potentials and a standard electronystagmography test battery. In the present study, the entire subject population assessed showed hypofunctional caloric responses and absent VEMPs. Two out of the three subjects were asymptomatic of vestibular dysfunction. On the clinical tests of stability, two subjects showed deviations to the right, while one subject performed normally. Thus, the present study indicates a possible involvement of peripheral vestibular nerve involvement in individuals with auditory neuropathy.     

Perceptual characterization of children with auditory neuropathy

OBJECTIVE: To characterize the perceptual abilities of a group of children with auditory neuropathy (AN)-type hearing loss, correlating results on a range of psychophysical tasks with open-set speech perception performance. DESIGN: Frequency resolution, temporal resolution and frequency discrimination ability was assessed in a group of 14 children with AN. Data also were obtained from a cohort of matched subjects with sensorineural hearing loss, and from a group of normally hearing children. RESULTS: Frequency resolution (notched noise masking) results for the AN subjects were equivalent to those of the normal-hearing subjects reflecting the "normal" outer hair cell function that characterizes the AN condition. Temporal resolution (TMTF) findings were, however, abnormal in many AN subjects and the degree of temporal disruption was correlated with speech discrimination (CNC) score. Frequency discrimination ability (for both fixed and frequency modulated stimuli) was also affected in those children with poor temporal resolution. CONCLUSIONS: The findings of this study indicate that the perceptual profiles of children with AN are quite different from those with sensorineural hearing loss. Where subjects in the latter group presented with impaired frequency resolution and normal temporal processing, the AN subjects typically showed normal frequency resolution and varying degrees of temporal disruption. The severity of this temporal abnormality, which appeared to affect both temporal resolution/amplitude modulation detection and the temporal aspects of frequency discrimination (such as phase locking), was strongly correlated to speech perception performance.     

Evaluation of brainstem function in patients with spasmodic dysphonia using vestibular evoked myogenic potentials and auditory brainstem responses

CONCLUSION: The vestibular area is closer than the auditory region to nucleus ambiguus. If a 'shared' lesion involves regions of adjacent nuclei of the brainstem in patients with spasmodic dysphonia then vestibular area involvement is more possible than that of the auditory region. OBJECTIVES: The authors hypothesize that lower brainstem lesions and involvement of descending pathways of the spinal tract may be the site of lesion in patients with spasmodic dysphonia. PATIENTS AND METHODS: Ten patients with spasmodic dysphonia were tested using the auditory brainstem response (ABR) and vestibular evoked myogenic potentials (VEMPs). RESULTS: No ABR abnormalities were found in right ears. Results of ABR on the left ear showed that one patient had abnormal ABR. This patient had severe sensorineural hearing loss on the left side. VEMPs displayed normal response in two patients bilaterally. First positive (p13) and second negative (n23) waves of VEMP could not be recorded in three cases unilaterally and in five patients bilaterally.     

Autosomal recessive hereditary auditory neuropathy

Objectives: Auditory neuropathy (AN) is a sen-sorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and patho-physiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination, pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion - product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were obs