Characteristics of presbycusis: evaluated by pure tone audiometry

In order to explore the incidence and course of presbycusis, 82 elderly and aged as well as 16 young persons were studied by Bekesy audiometry, including tone stimuli of different durations, SISI, and tone decay tests. Results showed that the hearing threshold has elevated in all the old persons. Positive correlations were found between age and hearing problems. Based on analyses of the DLI, temporal integration and tone decay tests, characteristics of the cochlear lesion had been suggested and some might exhibit retrocochlear dysfunctions.     

Psychoacoustical performance in children.

In order to contribute to knowledge of the elementary auditory functions in infancy, a group of normally hearing children below the age of four years was examined using advanced tests for cochlear (remote masking, brief-tone audiometry, critical ratio) and central auditory functions (masking-level difference). The results showed that both cochlear and central auditory functions were almost the same in three-year-olds as they were in adults, if not better. This behavior is similar to that recorded with electrophysiological methods and leads to the conclusion that at age three years the auditory system has completed its neurofunctional maturation and it is therefore completely efficient in its elementary psychosensorial functions.     

Phase audiometry in neuroaudiological practice.

Six groups of subjects, altogether 107 in number, were studied with phase audiometry. Three control groups were studied (normal-hearing healthy controls, persons with cochlear hearing losses, and patients with neurological disease not affecting the auditory system), and three patient groups were studied (patients with cerebellopontine angle tumours, with brainstem lesions, and with temporal lobe lesions). Two phase audiometers were used. The sensitivity was 85% for patients with cerebellopontine angle tumours, 71% for patients with brainstem lesions, and 69% for patients with temporal lobe lesions. There was good agreement between the phase audiometers, though one of them (BIAB Phase Audiometer) had better results for two of the patient groups. Phase audiometry can be recommended in neuroaudiological practice.     

颞叶癫痫患者的中枢听功能初探

目的采用汉语最低听觉功能测试（minimal auditory capabilities inchina，MACC）中背景噪声下言语测听法（speech-perception-in-noise test，SPIN），评价颞叶癫痫患者的中枢听觉功能。方法对9例经脑电图和MRI、CT检查后神经内科确诊的颞叶癫痫患者，进行SPIN、听性脑干反应（auditory brainstem response，ABR）测试。选择19例年龄、性别相匹配的健康人做对照组，进行SPIN测试。所有受试者均经询问病史、耳科检查及纯音测听、声导抗测定除外传导、感音神经性及混合性聋，且纯音听阈均在25dB以内。SPIN测试材料中测试言语和噪声材料，采用独立声道录制，通过预实验选择测试信噪比（S／N）为-25dB。测试时，每受试句均朗读2次，并对2次的结果分别进行记录和比较。结果在ABR测试中，癫痫患者仅V波潜伏期左耳较右耳延长，且差异有统计学意义（P〈0．05），余各波潜伏期及波间期差异均无统计学意义（P〉0．05）；在SPIN测试中，健康对照组第1次聆听左右耳间得分比较，差异无统计学意义（P〉0．05），第2次聆听时，差异有统计学意义（P〈0．05）；颞叶癫痫患者左右耳间得分比较，第1次和第2次聆听的差异均无统计学意义（P〉0．05），而颞叶癫痫患者无论在单耳、双耳聆听以及第1次和第2次聆听的SPIN得分，与健康对照组相比，差异均有统计学意义（P〈0．01）。由于9例癫痫患者中有3例为右侧颞叶病变，余为双侧颞叶病变，故未对左、右侧颞叶病变与左、右利手的关系可能对实验造成的影响进行统计分析。结论本组颞叶癫痫患者在纯音测听、ABR检查无明显异常，而SPIN测试言语识别率明显低于对照组，差异有统计学意义，证明颞叶癫痫患者具有中枢听功能障碍，同时提示SPIN是一项敏感、无创的中枢听觉功能检查方法，建议临床上将其作为听处理套查方法之一。     

The magnetless Clarion cochlear implant in a patient with neurofibromatosis 2.

We present our experience using the Clarion magnetless multichannel cochlear implant with a woman profoundly deafened following bilateral acoustic neuromata as a consequence of neurofibromatosis 2 (NF2). The right neuroma had been previously removed without an attempt at neural preservation. On the left, however, a posterior fossa approach had been taken with the aim of preserving hearing. Although the left cochlear nerve appeared to be undamaged at the end of the operation, no hearing thresholds could be elicited on post-operative audiometry, because of damage either to the cochlear nerve or to the blood supply to the cochlea. Round window electrical stimulation subsequently produced a perception of sound, confirming that the cochlear nerve was capable of functioning and that a cochlear implant would be effective. Because she would need regular magnetic resonance imaging (MRI) to monitor existing and future NF2 lesions, it was decided to use a magnetless Clarion implant, which has been shown to be MRI compatible. We report our experience of using the device in this case and discuss some of the issues related to the provision of cochlear implants to patients with NF2.     

Far-advanced otosclerosis. Cochlear implantation vs stapedectomy

In 1981, our group, as part of a Food and Drug Administration investigator team directed by William House, performed Illinois' first cochlear implantation. We have since performed cochlear implantations in ten other persons. Since May 1980, approximately 35 severely to profoundly deaf persons per year have been referred to our clinic for evaluation. A small number of these patients had far-advanced otosclerosis. In these cases, exploratory tympanotomy and stapedectomy followed by rehabilitation with a hearing aid was a more appropriate management than cochlear implantation. Case histories and a temporal bone study of far-advanced otosclerosis are presented.     

语前聋儿人工耳蜗植入术后心理物理测试的探讨

目的探讨符合语前聋儿心理特点的人工耳蜗植入术后心理物理测试手段.方法采用行为观察法和游戏测听法,对86名接受了人工耳蜗植入手术的语前聋儿进行术后心理物理测试.结果84例(96.51%)测试出听性反应,其间1例第13、14号电极引起非听性反应,2例(2.33%)电极植入失败.41例(47.67%)一月内、39例(45.34%)三月内、4例(4.65%)六个月建立起听性条件反应.各患儿的T、C值均不相同,无正常值范围,在测试的三个月内有T值渐减小、C值渐增大的趋势,声场啭音测试显示患儿听阈都在长时间平均会话声谱(言语香蕉图)上限,对言语的强声和音响器具的强声无不适感觉.结论采用符合语前聋小儿心理特点的人工耳蜗植入术后心理物理测试方法,患儿很快建立听性条件反应,声场评估显示参数设置适宜.     

Methods for early identification of noise-induced hearing loss.

An ideal test for identifying shifts in cochlear function would be highly repeatable and sensitive to minor damage. Three types of otoacoustic emission (OAE) test and pure-tone audiometry were evaluated for this purpose. They were compared in terms of test-retest repeatability within subjects and sensitivity to differences between subjects. The OAE measures were transiently evoked either conventionally (TEOAE) or using maximum length sequences (TEOAE-MLS), or continuously evoked as distortion products (DPOAEs). Several stimulus conditions were evaluated for each type. Thirty eight subjects with normal hearing or mild hearing losses were tested on all measures. Test-retest repeatability was rescaled according to the sensitivity of each measure to differences in hearing threshold level, thus allowing a direct comparison across methods. The most repeatable method thus defined was TEOAE-MLS which gave a rescaled standard deviation of 1.8 dB on replication. This was followed by TEOAE and DPOAE which gave rescaled standard deviations of 2.9 and 3.1 dB, respectively. All were more reliable than pure-tone audiometry which had a standard deviation of 4.9 dB. It is concluded that the various OAE measures have the potential to distinguish small changes in cochlear function from measurement uncertainty, and hence show promise for monitoring cochlear function in ears exposed to noise or other hazards.     

Audiologic Diagnosis of Central versus Eighth Nerve and Cochlear Auditory Impairment

122 subjects divided into four groups according to the site of lesion (cochlea, eighth nerve, brainstem and temporal lobe) were subjected to an audiometric test battery, including pure-tone sensitivity measures, recruitment testing, tone decay, Békésy audiometry, speech audiometry, stapedius reflex measures and auditory brainstem response (ABR) audiometry. The results were contrasted among the four groups by calculating several measures of test performance, including sensitivity, specificity, efficiency, A' (test performance) and plots on the receiver operating characteristic (ROC) space of pure positives versus false alarms. In the differential diagnosis between eighth nerve and cochlear site, the various measures did not rank the tests in the same order: (a) for efficiency: ABR, Békésy audiometry; (b) for A' (similarly to the analysis into the ROC space): ABR, recruitment, Békésy, stapedius reflex, speech audiometry, tone decay. In distinguishing an eighth nerve from a brainstem site, it is important to consider amount of hearing loss, presence of tinnitus, abnormal tone decay and Békésy audiometry patterns. ABR adds significant diagnostic efficiency only when waves II, III and V are detectable: a prolonged I–II interpeak interval (IPI) and a normal III-V IPI are characteristic of the eighth nerve site. ABR gives good diagnostic support in the intrinsic brainstem lesions by suggesting changes in the generator sites of the component waves. The audiometric diagnosis of temporal lobe lesions involving the auditory cortex still relies upon speech audiometry: tests specifically designed for this purpose by Bocca and Calearo and by Jerger - i.e. the 'sensitized sentences' and the identification of synthetic sentences under ipsi- or contralateral competing message - are commendable for their sensitivity and efficiency in distinguishing brainstem from temporal lobe sites. In brainstem sites, the most affected ear is ipsilateral to the lesion for ABR, but contralateral for speech audiometry.     

水杨酸钠对豚鼠畸变产物耳声发射的影响

本文以10％水杨酸钠400mg／kg经豚鼠腹腔注射2小时和4天后,进行较系统的畸变产物耳声发射（DPOAE）测试,并以自身为对照,探讨用药前后水杨酸钠对豚鼠DPOAE的影响。结果发现,用药2小时和4天后,水杨酸钠具有对DPOAE相似的影响作用;水杨酸钠在低刺激强度下可明显降低DPOAE的测出率;对各频率DPOAE的幅值和阈值分别有降低和升高的作用,前者降低2～6dB,后者升高3～9dB,均以低频为甚;水杨酸钠对DPOAE的潜伏期和增长率无明显影响。提示水杨酸钠主要影响DPOAE的发生过程,而对发生后的DPOAE特性影响不大。通过对水酸钠对耳蜗机械特性影响的分析,认为该结果符合水杨酸钠主要影响耳蜗及毛细胞生理功能的药理学特点,可能为其可逆性耳毒性的耳蜗机制之一,有助于解释耳蜗性聋和耳鸣的发病机制。     

Audiologic diagnosis of central versus eighth nerve and cochlear auditory impairment

122 subjects divided into four groups according to the site of lesion (cochlea, eighth nerve, brainstem and temporal lobe) were subjected to an audiometric test battery, including pure-tone sensitivity measures, recruitment testing, tone decay, Békésy audiometry, speech audiometry, stapedius reflex measures and auditory brainstem response (ABR) audiometry. The results were contrasted among the four groups by calculating several measures of test performance, including sensitivity, specificity, efficiency, A' (test performance) and plots on the receiver operating characteristic (ROC) space of pure positives versus false alarms. In the differential diagnosis between eighth nerve and cochlear site, the various measures did not rank the tests in the same order: (a) for efficiency: ABR, Békésy audiometry; (b) for A' (similarly to the analysis into the ROC space): ABR, recruitment, Békésy, stapedius reflex, speech audiometry, tone decay. In distinguishing an eighth nerve from a brainstem site, it is important to consider amount of hearing loss, presence of tinnitus, abnormal tone decay and Békésy audiometry patterns. ABR adds significant diagnostic efficiency only when waves II, III and V are detectable: a prolonged I-II interpeak interval (IPI) and a normal III-V IPI are characteristic of the eighth nerve site. ABR gives good diagnostic support in the intrinsic brainstem lesions by suggesting changes in the generator sites of the component waves. The audiometric diagnosis of temporal lobe lesions involving the auditory cortex still relies upon speech audiometry: tests specifically designed for this purpose by Bocca and Calearo and by Jerger - i.e. the 'sensitized sentences' and the identification of synthetic sentences under ipsi- or contralateral competing message - are commendable for their sensitivity and efficiency in distinguishing brainstem from temporal lobe sites. In brainstem sites, the most affected ear is ipsilateral to the lesion for ABR, but contralateral for speech audiometry.     

Audiological and radiological characteristics of a family with T961G mitochondrial mutation

Abstract

Objective: The aim of this study was to describe audiological and radiological characteristics, and other secondary aspects, in a family carrying a T961G mutation in the 12S rRNA mitochondrial gene. Design: Case report. Study sample: Six members of a family participated in an audiological evaluation that included pure-tone audiometry, immittance tests, auditory brainstem responses (ABR), and otoacoustic emissions (OAE). The radiological evaluation was conducted through temporal bone CT scans using a Toshiba 16 channels Aquilon Spirale. Neuropsychiatric evaluation was also administered. Results: Three participants were diagnosed with severe sensorineural hearing loss of cochlear origin and cochlear malformations visible in CT scans. One participant had a mild mixed-hearing loss and no cochlear malformations. Two participants had normal audiological and radiological findings. Conclusions: We believe our study can provide helpful insight on the clinical findings of a rare mutation, of which few data have been presented in literature.     

Loss of residual hearing after cochlear implantation

Many cochlear implant recipients have some measurable hearing prior to implantation. Animal studies have demonstrated some loss of viable neural elements resulting from both mechanical insertion trauma and long-term electrical stimulation. The effect of implantation of a long intracochlear multichannel electrode array and subsequent electrical stimulation on residual hearing was evaluated. Forty consecutive cochlear implant recipients were assessed by audiometry at the Colorado Ear Clinic between July 1985 and June 1988. Twelve of these patients (30%) had some measurable residual hearing before implantation, although all had profound hearing loss, with no understanding of speech. All patients received a multichannel cochlear implant with all 22 electrodes inserted in each patient by an experienced cochlear implant surgeon. Audiometric testing was repeated between 2 and 24 months after implantation. Pure-tone threshold responses in the implanted ear were significantly reduced postimplant, while puretone threshold responses in the nonimplanted ear were stable.     

听神经瘤致聋机理——14例(16耳)听神经瘤病人听力测试结果分析

目的 :探讨听神经瘤听力损失的病理生理机制。方法 :对 14例 (16耳 )听神经瘤患者行纯音听阈、阻抗、听性脑干反应 (ABR)、诱发耳声发射测试 (EOAE)及 CT和 (或 ) MRI扫描。 EOAE能引出的 4耳还检测其传出抑制功能 ,ABR不能检测且 EOAE不能引出的重度聋 (听力损失大于 80 d B)有 5耳行鼓岬刺激试验 (PST)。结果 :16耳听神经瘤中2耳 (12 .5 0 % )听力损失源于神经性损害 ;6耳 (37.5 0 % )蜗性损害 ;8耳 (5 0 % )蜗 -神经性损害。能引出 EOAE的 4耳均有传出功能障碍。结论 :EOAE可评价听神经瘤的耳蜗功能状态 ;ABR结合 PST能分析听神经瘤的蜗后神经功能。听神经瘤的听觉病理可同时或单独发生于听外周的耳蜗水平、第 对颅神经 (传入神经 )水平和橄榄核耳蜗传出神经水平。     

Otoacoustic emissions recorded in people with chronic migraine

Migraine, a moderate to severe chronic headache occurring on one or both sides, is a common disease affects young people. Although hearing loss in subjects with migraine is not rare, the correlation of migraine with hearing loss is not clear. In this study, we examined hearing loss in young migraine subjects to determine if migraine may be a factor in causing cochlear dysfunction. Seven college students with migraine and three age matched subjects without history of migraine were assessed using extended high frequency audiometry and distortion product otoacoustic emissions (DPOAEs). There was no significant difference in regular audiometry threshold between the migraine group and the control group. However, high frequency audiometry (9–16 kHz) showed thresholds at 25 dB nHL or higher in six out of twenty ears in the migraine group. The amplitude of DPOAEs were reduced for more than 10 dB in the migraine group in comparison with the control group. These data suggest that migraine may affect cochlear dysfunction evidenced by the reduced amplitude of DPOAE and high frequency pure-tone audiometry.     

Gamma-aminobutyric acidergic and glycinergic inputs shape coding of amplitude modulation in the chinchilla cochlear nucleus.

Amplitude modulation is a prominent acoustic feature of biologically relevant sounds, such as speech and animal vocalizations. Enhanced temporal coding of amplitude modulation signals is found in certain dorsal and posteroventral cochlear nucleus neurons when they are compared to auditory nerve. Although mechanisms underlying this improved temporal selectivity are not known, involvement of inhibition has been suggested. gamma-Aminobutyric acid- and glycine-mediated inhibition have been shown to shape the dorsal cochlear nucleus and posteroventral cochlear nucleus response properties to other acoustic stimuli. In the present study, responses to amplitude modulation tones were obtained from chinchilla dorsal cochlear nucleus and posteroventral cochlear nucleus neurons. The amplitude modulation carrier was set to the neuron's characteristic frequency and the modulating frequency varied from 10 Hz. Rate and temporal modulation transfer functions were compared across neurons. Bandpass temporal modulation transfer functions were observed in 74% of the neurons studied. Most cochlear nucleus neurons (90%) displayed flat or lowpass rate modulation transfer functions to amplitude modulation signals presented at 2540 dB (re: characteristic frequency threshold). The role of inhibition in shaping responses to amplitude modulation stimuli was examined using iontophoretic application of glycine or gamma-aminobutyric acidA receptor agonists and antagonists. Blockade of gamma-aminobutyric acidA or glycine receptors increased stimulus-evoked discharge rates for a majority of neurons tested. Synchronization to the envelope was reduced, particularly at low and middle modulating frequencies, with temporal modulation transfer functions becoming flattened and less bandpass in appearance. Application of glycine, gamma-aminobutyric acid or muscimol increased the modulation gain over the low- and mid-modulation frequencies and reduced the discharge rate across envelope frequencies for most neurons tested. These findings support the hypothesis that glycinergic and gamma-aminobutyric acidergic inputs onto certain dorsal cochlear nucleus and posteroventral cochlear nucleus neurons play a role in shaping responses to amplitude modulation stimuli and may be responsible for the reported preservation of amplitude modulation temporal coding in dorsal cochlear nucleus and posteroventral cochlear nucleus neurons at high stimulus intensities or in background noise.     

Intracochlear assessment of electrode position after cochlear implant surgery by means of multislice computer tomography

The development of electrode arrays, the past years, has focused on modiolus-hugging cochlear implant electrodes. Besides, atraumatic implantation of electrodes is of importance for the use in hearing preservation, in cases of combined electric and acoustic stimulation. Intracochlear positioning of the individual electrodes by means of multislice computer tomography (CT) has not yet been shown. In this study we formulated and tested a CT imaging protocol for postoperative scanning of the temporal bone in cochlear implant subjects. Both a fresh human temporal bone and a fresh human cadaver head were implanted with a cochlear implant. Multislice CT was performed for adequate depiction of the cochlear implant. All scans were analyzed on a viewing workstation. After mid-modiolar reconstruction we were able to identify the intracochlear electrode position relative to the scala tympani and scala vestibuli. This was possible in both the implanted isolated temporal bone and the fresh human cadaver head. The feasibility of imaging the electrode position of the cochlear implant within the intracochlear spaces is shown with multislice CT. An imaging protocol is suggested.     

蜗神经发育不良患者的听力学特征分析

目的探讨蜗神经发育不良(cochlear nerve deficiency,CND)患者的听力学特征。方法以30例(54耳)(男14例,女16例,年龄6月~29岁,平均4.9岁)内听道斜矢状位磁共振成像示蜗神经发育不良的患者为研究对象,回顾性分析患者的纯音测听或行为测听、声导抗、耳声发射、听性脑干反应(ABR)、听性稳态反应等听力学检测结果及颞骨高分辨CT(HRCT)结果,分析蜗神经发育异常者的听力学特征。结果 30例54耳蜗神经发育不良患者中,双侧24例(80%),单侧6例(20%),其中蜗神经缺如33耳,蜗神经细小21耳。54耳中,共有25耳(46.29%)伴内耳畸形,而单侧蜗神经发育不良者的对侧6耳中,50%(3耳)伴内耳畸形。纯音测听或行为测听和听性稳态反应结果均提示蜗神经发育不良患耳呈重度-极重度听力损失,且蜗神经缺如耳较蜗神经细小耳的听力损失程度更重。11耳(20.37%,11/54)蜗神经发育不良耳可在80~100 dB nHL高强度声刺激下引出听性脑干反应;6例双侧蜗神经发育不良者(20.0%,6/30)中7耳(1例双耳,5例单耳)全部频率或部分频率引出DPOAE,但其中5耳未引出ABR,2耳分别于100和90 dB nHL刺激声强下引出ABR。结论蜗神经发育不良患者常表现为重度-极重度听力损失,近一半伴内耳畸形,部分患耳可引出DPOAE,而ABR严重异常或缺失。     

The effect of epidural anaesthesia and size of spinal needle on post-operative hearing loss.

Forty-five patients who were to undergo elective urological operations were evaluated. In the pre-operative period and on the third or fourth post-operative day audiometry was performed. Epidural anaesthesia was performed in 15 cases, spinal anaesthesia was performed in 15 cases with 25 G needles, and in 15 cases with 22 G needles. No statistically significant hearing loss was observed in the post-operative period compared to preoperative period in the epidural anaesthesia group. In the post-operative period, the hearing loss observed in the 25 G-spinal anaesthesia group was significantly (P < 0.01) less than that seen in the 22 G group. None of the patients had headache after spinal anaesthesia. It was concluded that pure tone audiometry is a more sensitive indicator of cerebrospinal fluid leakage than post-operative headache.     

Noise-Induced Changes of the Auditory Brainstem Response to Speech—a Measure of Neural Desynchronisation?

It is commonly assumed that difficulty in listening to speech in noise is at least partly due to deficits in neural temporal processing. Given that noise reduces the temporal fidelity of the auditory brainstem response (ABR) to speech, it has been suggested that the speech ABR may serve as an index of such neural deficits. However, the temporal fidelity of ABRs, to both speech and non-speech sounds, is also known to be influenced by the cochlear origin of the response, as responses from higher-frequency cochlear regions are faster and more synchronous than responses from lower-frequency regions. Thus, if noise caused a reweighting of response contributions from higher- to lower-frequency cochlear regions, the temporal fidelity of the aggregate response should be reduced even in the absence of any changes in neural processing. This ‘place mechanism’ has been demonstrated for non-speech ABRs. The aim of this study was to test whether it also applies to speech ABRs. We used the so-called ‘derived-band’ method to isolate response contributions from frequency-limited cochlear regions. Broadband and derived-band speech ABRs were measured both in quiet and in noise. Whilst the noise caused significant changes to the temporal properties of the broadband response, its effects on the derived-band responses were mostly restricted to the response amplitudes. Importantly, the amplitudes of the higher-frequency derived-band responses were much more strongly affected than those of the lower-frequency responses, suggesting that the noise indeed caused a reweighting effect. Our results indicate that, as for non-speech ABRs, the cochlear place mechanism can represent a potentially substantial confound to speech-ABR-in-noise measurements.