Audiologic presentation of cerebellopontine angle cholesteatoma

OBJECTIVE: The aim of this study was to examine the audiologic presentation of patients with cerebellopontine angle (CPA) cholesteatoma. DESIGN: Retrospective case review. SETTING: Neuro-otologic tertiary referral centre. METHODS: The study population consisted of 11 patients with CPA cholesteatomas. The patients underwent a standard audiologic investigation in the preoperative setting, which consisted of pure-tone audiometry, speech audiometry, and auditory brainstem response (ABR). MAIN OUTCOME MEASURES: The audiologic parameters that were analyzed were the pure-tone threshold, pure-tone average (PTA), and speech discrimination scores (SDSs). The morphology and latency of the ABR were evaluated. In addition, the clinical and radiologic presentations of the lesions were reviewed. RESULTS: The mean PTA in the diseased ear was 22.6 dB HL (SD 18.2), whereas in the contralateral ear, it was 19.1 dB HL (SD 19.6). In 4 patients, the hearing loss was asymmetric, with the diseased ear being the worse ear. The mean SDS was 82.28% in the affected ear and 95.28% in the contralateral ear. ABR was abnormal in 9 of 10 cases (90%), with only the affected ear being abnormal in 4 cases. In the other 5 cases, the ABR was bilaterally abnormal. CONCLUSIONS: CPA cholesteatomas are very slow-growing lesions that involve the eighth cranial nerve. The paucity and insidious onset of symptoms mean that the diagnosis is often late, permitting the lesions to reach impressive dimensions at the time of diagnosis. Although magnetic resonance imaging represents the gold standard in the diagnosis of these lesions, ABR proved to be of value in the assessment of the auditory pathway, especially in those patients referred with a vague symptomatology and with normal hearing.     

Functional hearing loss in children

This report reviewed 39 school-age children diagnosed as having a functional hearing loss utilizing auditory brainstem response (ABR) audiometry during the past 5 years at the Department of Otolaryngology, Kyushu University Hospital in Japan. Twenty-seven cases were females and 12 were males. Seven cases had a hearing loss unilaterally and 32 bilaterally. Although pure-tone audiometry revealed a variety of audiogram shapes, two-thirds of the cases had a flat or saucer-shaped audiogram with a mild to moderately severe hearing loss. ABR audiometry for the frequencies of 1, 2 and 4 kHz indicated a normal hearing threshold in 65 ears of 35 patients, and mild threshold elevations of at least one frequency in the remaining 6 ears of 4 patients. Three illustrative cases were demonstrated, and a discussion was held regarding the features in audiometric tests, and environmental factors surrounding the children with this condition. We emphasized that the physiological hearing measurement such as ABR audiometry should be performed when any discrepancy was noted between the patient's history and results of pure-tone audiometry, because of not infrequent occurrence of functional hearing loss.     

Follow-up studies and prognostic references for pre- and post-therapy pure tone audiometry and acoustically evoked potentials in sudden deafness

In 95 patients with unilateral sudden deafness, pure-tone and speech audiometry was performed before, during and after drug therapy. Auditory brain-stem evoked responses (ABR) were recorded in all cases. Stapedial reflex audiometry and SiSi tests were also performed. The tone-audiometry thresholds for the frequencies 250, 500, 1000, 2000, 4000 and 6000 Hz were analysed, and likewise the ABR latencies for waves I to V and the I-III, III-V and I-V interpeak latencies. 57 patients showed a flat hearing loss before therapy, 31 patients a high tone loss and 7 patients a hearing loss for low frequencies. Recruitment was positive in 77%. After therapy 81% of the patients showed increased pure-tone thresholds of more than 20 dB. In 11 patients ABR showed signs for retrocochlear hearing loss; in 6 patients initially no waves could be reproduced. The tendency for remission was best in patients with flat hearing loss of less than 40 dB and normal or only moderate alterations of the ABR. In patients with severe hearing loss of greater than 40 dB and signs for retrocochlear lesions in ABR, the tendency of remission was worse. In these cases recruitment was mainly negative.     

Auditory neuropathy in childhood

The combination of transient otoacoustic emissions (TOAE) and auditory brainstem responses (ABR) permits us to identify a group of patients with auditory neuropathy. The clinical and therapeutic aspects of these patients are a challenge for otological practice. The patients underwent ENT, neurological, and otological examination using audiometry, tympanometry, stapedial reflex, OAE, or ABR, depending on the patient. TOAE and tympanograms were normal in all cases. The stapedial reflex and ABR were absent in all cases. Logoaudiometry showed a disproportionate decrease in speech comprehension in relation to each patient's audiogram. These audiograms revealed mild-to-moderate hearing loss. These findings suggest that the lesion is sensorineural with normal function of the external hair cells. However, we could not determine if the lesion lay in the internal hair cells, the eighth cranial nerves, or both sites. The causes of hearing loss were: hyperbilirubinemia, perinatal asphyxia, or idiopathic. All the patients were treated by a speech therapist: The results obtained with hearing aids vary. Successful speech rehabilitation depends on early treatment.     

Neurotologic disease in four patients with normal audiometric findings

Clinical suspicion remains an underlying diagnostic clue in the evaluation of patients with unconfirmed acoustic neuromas. This is particularly true when initial otologic and audiologic evaluations are equivocal. This paper summarizes a series of four patients each who demonstrated normal audiometric (pure-tone and conventional speech audiometry) and/or ABR findings in the presence of surgically confirmed intracanalicular or cerebellopontine angle tumors. Three of the patients presented with evidence of "classical" acoustic tumors, whereas the fourth patient revealed a benign internal auditory canal capillary hemangioma. Audiologic evaluation, ABR measures, and MRI scanning demonstrate the relationships observed in each of the four patients. Diagnostic strategies illustrate the importance of cross-check principles (audiologic, electrophysiologic, and imaging techniques) in the diagnosis of posterior fossa tumors. The presence of normal pure-tone thresholds should not discourage the pursuit of additional diagnostic measures if clinical suspicion remains a factor in comprehensive patient management.     

Hearing loss in prison inmates

The incidence of hearing disorders in 34 State Penitentiary prison inmates all with a previous history of drug abuse were investigated. Subjects were evaluated using routine pure-tone air conduction audiometry, immittance measures, and short-latency auditory brain stem responses. Of the 34 inmates, 20 (58.8%) demonstrated normal bilateral peripheral hearing sensitivity, whereas 10 (29.4%) inmates presented with some degree of hearing impairment. In addition, the conflicting results of elevated pure-tone thresholds with normal immittance measures and normal ABR findings suggested that four (11.8%) subjects exhibited functional hearing loss. The results of this study support the reported high incidence of hearing loss in the prison population. The synergistic effects of drug abuse, noise exposure, and head trauma as possible contributing factors are discussed.     

Long-term objective and subjective audiologic consequences of closed head injury.

During a period of 5 years, a total of 47 patients, 16-60 years of age, with major closed head injury (CHI) were admitted to 2 Swedish medical centres. Seven to 11 years after injury, 25 of them (mean age 40.8 years; range 25-59 years) were evaluated using peripheral and central auditory tests, and most of them also completed 2 questionnaires concerning self-assessed hearing ability and quality of life. Twenty-two patients did not participate in the long-term follow-up tests: 15 were excluded for medical reasons and 4 did not wish to participate; an additional 2 were impossible to trace and 1 had died. As many as 68% of patients (17/25) demonstrated abnormalities on 1 or more of the audiometric tests, 14 on pure-tone audiometry (p < 0.02) and/or central audiometric tests (3 on central tests only and 2 on pure-tone audiometry only). Four out of six patients with available early post-traumatic audiograms showed a significant progressive deterioration. As a group, their assessments of hearing ability and quality of life were equal to or better than those of the controls. These results may indicate that a higher priority should be given to obtaining an early audiologic evaluation of every CHI patient than is the rule today. The impact of post-traumatic progress and central lesions on social hearing at an advanced age is highlighted.     

Decreased hearing after combined modality therapy for head and neck cancer

PURPOSE: Combined platinum-based chemoradiation therapy is frequently being used as therapy for head and neck cancer at multiple sites. These therapies are individually ototoxic, but little has been reported on their combined toxicity. MATERIALS AND METHODS: A retrospective investigation of 37 patients known to have undergone therapy with both agents, in combination, for head and neck malignancy was performed. Sixty percent of the patients had complaints of hearing loss subjectively. Reliable pretreatment and posttreatment audiograms were obtained on 15 of these patients. Audiograms were analyzed for sensorineural changes at 0.5, 1, 2, 4, and 8 kHz. RESULTS: By paired t test analysis, there were significant changes in the patients with pretreatment and posttreatment audiograms at all frequencies. More than 50% of the patients had a change of 10 dB or greater in their pure-tone average. More than 85% of the patients experienced changes in their hearing at 4 and 8 kHz. CONCLUSIONS: We conclude that patients undergoing combined modality therapy for head and neck cancer experience hearing loss. We recommend that hearing assessment, including pretreatment and posttreatment audiometry, be performed in all patients undergoing combined platinum-based chemotherapy and radiation for the treatment of head and neck cancer.     

Auditory brain stem responses in patients with human immunotropic virus infection of different stages.

Thirty patients (26 men, 4 women) with human immunotropic virus infection of different stages were examined. Eleven patients had a history of i.v. drug abuse, nine patients had a history of treated lues infection, and one patient suffered from Kaposi's sarcoma. At the time of the examination, opportunistic infections or acute encephalitis were not apparent in any patient. All patients underwent otoneurological examinations, including pure-tone audiometry, caloric vestibular testing, and recording of the auditory brain stem responses (ABR). Six patients reported onset of hearing impairment during the last 3 yr. Two of them had flat sensorineural hearing loss; in the other cases, pure-tone audiometry showed high tone hearing loss with negative recruitment. ABRs were normal in 19 cases, with the latencies for waves III and V and for the I-V interpeak latency significantly delayed when compared to the values of the control group. The frequency of abnormal ABR findings did not correlate to the stage of the disease. The results of the study indicate that auditory and, more specifically, ABR abnormalities commonly occur in human immunotropic virus disease. More studies are necessary to prove whether the ABR is suitable to monitor therapeutic effects.     

82例耳鸣患者半倍频程频率纯音测听的特征及意义

目的 :观察常规倍频程纯音测听听阈无异常的耳鸣患者的半倍频程频率测试结果并探讨其特征及临床意义。方法 :应用纯音听力计对 82例 (14 0耳 )倍频程纯音测听听阈无异常的耳鸣组患者和 30例 (6 0耳 )正常对照组进行半倍频程频率测试。结果 :耳鸣组 14 0耳中 ,发现 37.14 %存在听力下降 ;主要为高频下降 ;大多为轻度下降 ;下降的频率与耳鸣频率有高度一致性 ;耳鸣的强度 (dBSL)与听力下降与否无关。结论 :半倍频程频率测试方法可为倍频程纯音测听听阈无异常的耳鸣患者早期听力损害的检出提供直接参考依据 ,对临床早期发现其潜在的耳蜗病变有积极意义     

梅尼埃病与偏头痛性眩晕的听-前庭功能比较

目的探讨梅尼埃病与偏头痛性眩晕的听功能及前庭功能状态的不同特点,进行比较分析,为二者的鉴别诊断提供帮助。方法回顾性分析2007年5月至2008年9月山东省立医院眩晕门诊52例梅尼埃病患者与36例偏头痛性眩晕患者的临床资料,全部患者均在急性期或亚急性期行纯音测听、视频眼震电图、冷热试验、前庭诱发的肌源性电位检查,部分梅尼埃病及全部偏头痛性眩晕患者行高刺激率听性脑干反应检查,对二者的听力与前庭功能检查结果进行比较分析。结果梅尼埃病患者共52例,男24例,女28例,年龄14-70岁,平均45.8岁。纯音测听异常52例,均为单侧感音神经性聋。视频眼震电图检查示中枢性异常眼动10例。冷热试验异常37例,均为单侧半规管反应低下。前庭诱发的肌源性电位检查异常31例。行高刺激率听性脑干反应检查共32例,5例异常。偏头痛性眩晕患者共36例,男8例,女28例,年龄16-62岁,平均43.6岁。纯音测听异常9例,均为单侧轻至中度感音神经性聋。视频眼震电图检查示中枢性异常眼动17例。冷热试验异常8例,均为单侧半规管反应低下。前庭诱发的肌源性电位检查异常18例,高刺激率听性脑干反应检查异常22例。经统计学分析,二者纯音测听、中枢性眼动检查、冷热试验及高刺激率听性脑干反应的检查结果差异有显著性。结论与梅尼埃病相比,偏头痛性眩晕患者纯音测听及冷热试验异常较少见,中枢性服动检查及高刺激率听性脑干反应异常率较高。在结合患者病史及临床表现的基础上.以上检查可为二者的鉴别提供辅助参考。     

Long-term audiometric follow-up of click-evoked auditory brainstem response in hearing-impaired infants

Conventional pure-tone thresholds were collected as determined at ages between 4 and 8 years from a group of 163 infants, tested by auditory brainstem response (ABR) in the age range between 1 and 3 years old for objective hearing assessment. The subjects suffered from a variety of degrees and types of sensorineural hearing impairment. The prognostic value of the ABR peak V thresholds in response to 0.1 ms clicks with respect to the behavioural thresholds at octave frequencies from 125 to 8,000 Hz obtained later is evaluated. Correlation between ABR and behavioural thresholds is largest in the 1,000- to 8,000-Hz frequency range. Predicted pure-tone audiograms (mean and SD) were determined for each 10-dB class of ABR thresholds. SDs are in the order of 15 to 18 dB in the 500- to 4,000-Hz range and slightly higher at adjacent frequencies (i.e., somewhat larger than in comparable adult studies). Mean pure-tone thresholds in the 1,000- to 8,000-Hz frequency range are up to 20 dB worse than ABR thresholds, which is opposite to findings in normally-hearing subjects. Thus, with an increasing degree of sensorineural hearing impairment, pure-tone thresholds increase at a significantly higher rate than ABR thresholds. The observation is explained in terms of reduced temporal integration in cochlear hearing loss. ABR thresholds worse than 80 dB nHL are demonstrated to have very limited predictive value with respect to the amount of residual hearing, not only in the low- but also in the high-frequency range. The presence of otitis media during ABR testing is shown to make estimation errors increase to more than 25 dB (SD).     

Reliability and validity of industrial audiometry: Implications for hearing conservation program design.

Hearing conservation in industry relies heavily on monitoring audiometry to detect early noise-induced hearing loss in workers who are exposed to potentially damaging noise, with or without hearing protectors. The “real-world” reliability and validity of these measurements, as well as otoscopic observations in industry, have not been extensively investigated. In addition, there is considerable controversy over the selection of a definition of “significant threshold shift” in industrial audiometry. These and related issues were considered in a series of three studies utilizing data from an active hearing conservation program. Test-retest variability in industry is much higher than has been reported for clinical settings; this variability is reduced by pure-tone averaging. Workers referred for otologic evaluation were found to have hearing levels which were, on the average, about 5 dB better than indicated by plant audiometry, even without excluding 4% of referred workers who had unilateral deafness and showed “shadow curves” on the plant audiograms. Otoscopic data obtained by the plant audiometrists were uncorrelated with the results of otoscopy by consultant otologists. Techniques borrowed from decision theory and signal detection theory were used to evaluate possible criteria for significant threshold shift. Criteria based on pure-tone averaging were superior to those based on a certain amount of threshold shift for any frequency tested. It is proposed that a significant threshold shift be defined as a 10 dB or greater change for the worse for either the 0.5, 1,2 kHz pure-tone average or the 3, 4, 6 kHz pure-tone average, in either ear, and that such shifts be validated by prompt retesting. Even with this criterion, a substantial number of shifts (most shifts, in some situations) will be either spurious or attributable to disorders other than noise-induced hearing loss, such as presbycusis. Otologic referral in cases of large or repeated shifts may prevent unjustified administrative actions, to the advantage of both workers and management. A practical consequence of the use of monitoring audiometry may be a de facto lowering of the permissible exposure level to 85 dBA TWA.     

Some comparisons between auditory brain stem response thresholds, latencies, and the pure-tone audiogram

Aspects of auditory brain stem responses (ABR) and pure-tone behavioral audiograms were compared in patients with cochlear hearing loss. Click-evoked ABR thresholds appeared to be related most closely to the audiometric thresholds at 2000 and 4000 Hz, with relatively poor agreement at either 1000 or 8000 Hz. These results were related to the amplitude spectrum of the eliciting stimulus. The slope of the wave V latency-intensity function appeared to be related to the configuration of the hearing loss. Patients with high-frequency sensorineural losses had steeper slopes than normal subjects, whereas patients with flat sensorineural losses had shallower slopes. These results were related to the principle that response latency is determined by the cochlear region that predominates the ABR for different stimulus intensities.     

Prevalence of auditory neuropathy/synaptopathy in a population of children with profound hearing loss

OBJECTIVE: To examine the prevalence of auditory neuropathy/synaptopathy (AN/AS) in a cohort of children with profound hearing loss. METHODS: From 1997 until 2004, 5190 children, aged 1-15 years, whose hearing ability was uncertain or who had risk factors for hearing impairment were investigated with subjective and objective hearing tests. Three thousand four hundred and fifteen from these children were screened for AN/AS using pure-tone audiometry, impedance measurement, transient evoked otoacoustic emissions (TEOAE) and click-evoked auditory brainstem responses (ABR). RESULTS: From 3415 patients who participated in an ABR and TEOAE assessment, 379 children showed absent or elevated (> or = 80 dB nHL) ABR thresholds. Within this group we found 32 cases with evidence of AN/AS via visible TEOAE and/or cochlear microphonics (CM) coupled with absent ABR. In the remaining 3036 children, AN/AS, could be ruled out by means of detectable ABR-thresholds and coherent findings in pure-tone audiometry and TEOAE assessment. This results in a prevalence of AN/AS of 0.94% within the group at risk for hearing loss, compared to 8.44% among profoundly hearing impaired children. CONCLUSION: This study shows that AN/AS is a common finding in the population of hearing impaired infants. In the majority of our AN/AS children (50%, n=16), an early audiological diagnosis was made under the age of 12 months. Therefore, clinicians and other health care professionals should generally be sensitised for AN/AS in infants, so that an appropriate treatment can promptly be initiated. Further research on clinical and pathophysiological aspects is necessary to better identify and manage patients suffering from AN/AS.     

多频听觉稳态反应与40Hz听相关电位对儿童客观听阈评估的比较

目的通过对感音神经性聋患儿的多频听觉稳态反应（multiple frequency auditory steady--state response，MFASSR）测试结果进行分析，并比较其在0．5 kHz处与40 Hz听相关电位（40Hz auditory event related potential，40 Hz AERP）对客观听阈评估的准确性，为MFASSR临床应用提供指导。方法对感音神经性聋儿进行纯音测听、ABR、40 Hz AERP和MFASSR测试。MFASSR与ABR、40 Hz AERP测试均在睡眠状态下进行。按照测试结果分为ABR未引出组与ABR引出组。结果①MFASSR在0．5 kHz处引出率比40 Hz AERP低。②0．5 kHz MFASSR反应阈对纯音听阈的评估较1、2、4 kHz MFASSR反应阈对纯音听阈的评估差。③以纯音听阈为标准，在0．5 kHz处MFASSR与40 Hz AERP对纯音听阈的评估差别具有统计学意义（P=0．001），说明，在0．5 kHz处MFASSR对纯音听阈评估的准确性不如40 Hz AERP。结论MFASSR反应阈对0．5 kHz处纯音听阈的预测需要结合40 Hz AERP来判断。     

浅睡眠状态下的行为观察测听

目的 分别测试低龄儿双耳的听力状况.方法 对327名婴幼儿进行浅睡眠状态下的行为观察测听,并与click声刺激ABR结果进行比较;其中有58名婴幼儿一段时间后再进行游戏测听和纯音测听.结果 浅睡眠状态下的行为观察测听在2 kHz和4 kHz的平均反应阈与ABR的反应阈相当,但比跟踪测得的同频率纯音听阈值高约5～10 dB HL.结论 浅睡眠状态下的行为观察测听可分别测得低龄儿的双耳听反应阈.     

Auditory neuropathy : Diagnostic and therapeutic challenge report of first series of four cases from india

Auditory neuropathy (AN), a recently described clinical entity, is a sensorineural disorder where the patient has hearing loss with impaired word discrimination out of proportion to pure tone loss in the pressence of abnormal / absent auditory brain stem responses, and normal outer hair cell as measured by otoacoustic emissions and / cochlear microphonics. It is essential that the practicing, ENT surgeon have a high degree of suspicion of AN in patients complaining of difficulty in understanding speech with hearing loss and audiological evidence of dissociation between pure-tone and speech audiometry. Appropriate newer diagnostic tests of ABR and OAE and /or CM for confirmation of AN is essential. We present a series of four patients with auditory neuropathy from a tertiary care teaching hospital. This is the first Series of 4 cases of this clinical entity from the Indian subcontinent.     

尿毒症患者听力状况及其影响因素研究

目的观察尿毒症患者的听力状况,探讨引起尿毒症患者听力下降的原因。方法采用纯音测听和高刺激率ABR对30例（60耳）尿毒症患者及31例（62耳）非尿毒症者进行测试,用SPSS19．0软件进行统计分析。结果30例尿毒症患者中有26例伴有不同程度的听力下降,其中19例听力曲线为下降型,5例为平坦型,2例为单侧全聋和另侧下降型。尿毒症组内纯音测听结果与肌酐水平无相关（P〉0．05）。与尿素氨水平为负相关（P=0．011）,高刺激率ABR与纯音测听结果无相关（P〉0．05）。尿毒症组和对照组间高刺激率ABR波I～V潜伏期的差值有统计学意义（P〈0．05）。结论尿毒症患者的听力下降是以高频为主的下降型曲线,内耳血供不足是导致尿毒症患者听力障碍的一个主要因素。     

Auditory steady-state responses to multiple simultaneous stimuli in children with functional or sensorineural hearing loss

The goal of our study was to identify the role of auditory steady-state responses for hearing assessment in patients with functional hearing loss. The study design was to compare auditory steady-state response thresholds and standard pure-tone audiometry thresholds between patients with functional or sensorineural hearing loss. Subjects comprised 16 patients (24 ears) with functional hearing loss and 17 patients (24 ears) with sensorineural hearing loss. Differences and correlations between auditory steady-state response thresholds and standard pure-tone audiometry thresholds at 500, 1,000, 2,000 and 4,000 Hz were evaluated. In children with functional hearing loss, pure-tone audiometry thresholds and auditory steady-state response thresholds were significantly different at all frequencies and were not significantly correlated. In patients with sensorineural hearing loss, pure-tone audiometry thresholds and auditory steady-state response thresholds did not differ significantly at any frequencies and were significantly correlated. Auditory steady-state responses may have principal role in the assessment of auditory brainstem acuity, particularly at low frequencies in patients with functional hearing loss.