感音神经性聋耳听阈级与短声诱发听性脑干反应潜伏期的关系

分析感音神经神经性聋512耳的0．5k、1k、2k和4kHz纯音听阈级与短声诱发ABRⅠ、Ⅴ波潜伏期的关系，结果表明，各频率的有效刺激级（ECL）与Ⅰ、Ⅴ波潜伏期均有很好的相关性。与正常耳比较。显示感音神经性聋耳在能引出ABR时，就有重振现象。4kHz纯音主观听阈大于50dBHTL的感音性听力减退耳，ABR波Ⅴ潜伏期比同一有效刺激级的正常组短，Ⅰ－Ⅴ波间期与正常组一致。     

多频稳态诱发电位(ASSR)的临床应用研究(36例极重度感音神经性耳聋幼儿及32例成人感音神经性耳聋患者ASSR测试结果分析)

目的旨在探讨ASSR与ABR在极重度感音神经性耳聋幼儿及成人感音神经性耳聋患者测试中的临床应用价值.方法对36例(72耳)小于3岁极重度感音神经性耳聋幼儿分别行ASSR和ABR测试;对32例(64耳)成人感音神经性耳聋患者分别行ASSR和电测听测试.结果①极重度感音神经性耳聋幼儿ABR均未引出V波,而ASSR在0.5 kHz、1 kHz、2 kHz、4 kHz的引出率分别为66.67%、86.11%、88.89%、94.44%,ASSR在0.5 kHz、1 kHz、2 kHz、4 kHz的阈值均数、标准差分别为82.56±9.26 dB HL、90.31±6.94 dB HL、88.12±7.93 dB HL、88.62±8.12 dB HL.②对成人感音神经性耳聋患者0.5 kHz、1 kHz、2 kHz、4 kHz ASSR测试阈值与电测听语频听阈(dB HL)进行配对两两比较的t检验,各组P值均大于0.05,无显著性差异.结论ASSR有助于极重度感音神经性耳聋幼儿残余听力的客观评估,尤以高频听阈为佳;ASSR与电测听在感音神经性耳聋诊断上有良好的一致性.     

感音神经性聋患儿的听功能综合评估

目的探讨听力测试组合（ABR＋ASSR＋声场环境中的行为测听）在感音神经性聋患儿残余听力评估中的应用价值。方法48名（96耳）感音神经性聋患儿中能配合纯音测听的患儿19人（38耳）设为PTA组,进行纯音测听及ASSR检测;不能配合纯音测听的患儿29人（58耳）设为BA组,进行声场环境中的行为测听（behavior audiometry,BA）、ABR及ASSR检测。结果①PTA组0．5、1、2、4kHz各频率ASSR反应阈与纯音听阈显著相关（P〈0．01）,各频率相关系数分别为0．75、0．76、0．76、0．83,建立本实验室的ASSR—PTA直线回归方程;②BA组23耳ABR无反应但仍可引出ASSR,而ASSR无反应耳ABR均未能引出;BA组29例患儿中ASSR检测反应较好耳（29耳）在0．5～4kHz四个频率上,ASSR可测得83个反应阈值,行为测听可测得89个反应阈值,综合ASSR和行为测听可以得到96个反应阈值。结论与单项听力测试方法相比,听力测试组合（行为测听＋ABR＋ASSR）能为更小年龄、听力损失更重的患儿进行残余听力的评估,同时能对双侧耳间听力差异、各频率的听力损失程度进行评估,为听力损失病变的定位判断提供参考。     

68例感音神经性耳聋患者ASSR测试听阈与ABR测试V波反应阈的相关性研究

目的旨在探讨ASSR与ABR在诊断感音神经性耳聋中的相关性。方法68例临床诊断为感音神经性耳聋患者分别行0．5kHz，1kHz，2kHz，4kHzASSR测试及ABR测试，进行不同耳别、不同测试频率ASSR阈值与不同耳别ABRV波反应阈之间的相关分析。结果除了0．5kHz ASSR阈值与ABRV波反应阈的相关系数低而无显著意义外，1kHz，2kHz，4kHz ASSR阈值均与ABRV波反应阈有极显著性相关（P〈0．01），且随着测试频率的递增两者的相关系数随之增加，尤其是4kHz ASSR与ABRV波相关系数达到0．95以上（P〈0．01）。结论ASSR诊断感音神经性耳聋是可靠客观的，具有频率特性，可弥补ABR测试在诊断耳聋疾病中的频率局限性。     

多频稳态诱发电位和听性脑干反应对感音神经性聋儿童客观听阈的评估

目的比较多频稳态诱发电位(MASSR)与短纯音听性脑干反应(Tb-ABR)对感音神经性聋儿童客观听阈的评估。方法对37名感音神经性聋儿童分别测试MASSR反应阈、Tb-ABR反应阈和行为听阈,参照行为听阈,比较MASSR反应阈和Tb ABR反应阈对行为听阈评估的准确性。结果MASSR反应阈、Tb-ABR反应阈和行为听阈之间均有较高的相关性。二者在频率为2、4kHz时,对行为听阈的评估具有相似的准确性;但在频率为0.5、1kHz时,MASSR的准确性较Tb ABR的准确性高。结论MASSR和Tb-ABR均可用作感音神经性聋儿童言语频率客观听阈的评估,但MASSR在低频(0.5、1kHz)时较Tb-ABR的准确性高。     

隐性遗传性感音神经性聋

报告两个家系隐性遗传性感音神经性聋。一家系三代４人发病，均为男性，系为Ｘ连锁隐性遗传性感音性耳聋；另一家系三代３人发病，为常染色体隐性遗传。此两种类型隐性遗传性聋的家系，临床上较为罕见，为此对其发病特点及其诊断进行了讨论。     

感音神经性聋100耳的耳蜗电图分析

报道感音神经性聋100耳的耳蜗电图AP波和SP波的反应阈、两者的振幅、潜伏期及SP／AP波幅度比的测试结果。并对Metz重振阳性和阴性的AP反应阈与纯音听阈的关系。AP和SP波的振幅、潜伏期的关系以及SP／AP波幅比与Metz重振的关系等进行分析和讨论。     

急性低频感音神经性聋76例临床分析

目的探讨急性低频感音神经性聋(acute low-frequeacy hearing loss,ALHL)的临床特点及疗效。方法回顾性分析76例急性低频感音神经性聋患者的临床特征、听功能检查情况及以皮质类固醇激素、扩血管药物、神经营养药及高压氧治疗的疗效。结果 76例患者均以耳闷为主要症状,纯音听力曲线表现为低频下降型,中高频正常,单耳多发,女性多见,不伴眩晕且预后良好;治疗前后平均听阈值(125、250、500Hz)分别为30.5和14.7dB HL,治疗后较治疗前下降15.8dB;治愈率87.50%(70/80),有效率95.00%(76/80),仅2例(4耳)无效。结论 ALHL患者主要表现为耳闷,纯音听阈曲线为低频下降型,皮质类固醇激素及扩血管药物、神经营养药治疗有效。     

不明原因感音神经性聋患者红细胞免疫功能检测

为探讨不明原因感音经性聋患者红细胞功能，采用酵母菌花环试验对５０例不明原因感音神经性聋患者红细胞免疫功能进行检测，并与正常进行比较，结果显示：不明原因感音神经性聋患者红细胞Ｇ３ｂ受体花环率降低，红细胞免疫复合物花环率升高，且皆与正常组有显著性差异，提示不明原因的感音神经性聋患者有继发性红细胞免疫功能低下，可能与红细胞免疫调节功能紊乱有关。     

Cochlear microphonics in sensorineural hearing loss: lesson from newborn hearing screening

The diagnostic dilemma surrounding the presence of cochlear microphonics (CM) coupled with significantly elevated auditory brainstem response (ABR) thresholds in babies failing the newborn hearing screening is highlighted. A case report is presented where initial electo-diagnostic assessment could not help in differentiating between Auditory Neuropathy/Auditory Dys-synchrony (AN/AD) and sensorineural hearing loss (SNHL). In line with the protocol and guidelines provided by the national Newborn Hearing Screening Programme in the UK (NHSP) AN/AD was suspected in a baby due to the presence of CM at 85 dBnHL along with click evoked ABR thresholds of 95 dBnHL in one ear and 100 dBnHL in the other ear. Significantly elevated thresholds for 0.5 and 1kHz tone pip ABR fulfilled the audiological diagnostic criteria for AN/AD. However, the possibility of a SNHL could not be ruled out as the 85 dBnHL stimuli presented through inserts for the CM would have been significantly enhanced in the ear canals of the young baby to exceed the threshold level of the ABR that was carried out using headphones. SNHL was eventually diagnosed through clinical and family history, physical examination and imaging that showed enlarged vestibular aqueducts. Presence of CM in the presence of very high click ABR thresholds only suggests a pattern of test results and in such cases measuring thresholds for 0.5 and 1 kHz tone pip ABR may not be adequate to differentiate between SNHL and other conditions associated with AN/AD. There is a need for reviewing the existing AN/AD protocol from NHSP in the UK and new research to establish parameters for CM to assist in the differential diagnosis. A holistic audiological and medical approach is essential to manage babies who fail the newborn hearing screening.     

河南地区青年和儿童感音神经性聋患者中大前庭水管综合征的临床和基因诊断

目的通过对我国河南地区35岁以下青年及儿童感音神经性聋患者进行大前庭水管综合征(large vestibul araqueduct syndrome,LVAS)的临床诊断及基因突变热点筛查的分析,来探明这一地区LVAS的患病率,为耳聋防治工作的有效开展奠定理论基础。方法回溯性搜集2005年2月—2007年1月就诊的764例感音神经性聋患者的资料,对先天性耳聋患者、不明原因的进行性波动性听力下降者及与外伤不成比例的严重感音神经性聋患者均进行颞骨CT检查,对137名聋哑患者进行问卷调查,经问卷调查筛选出95名患者抽取血样提取基因组DNA,运用直接测序对突变热点SLC26A4 IVS7-2A>G进行筛查。结果临床诊断结果显示,LVAS患者占总调查人数的13.22%,在各种已知原因的耳聋中居于首位。突变热点筛查结果显示,SLC26A4 IVS7-2A>G在LVAS患者中的突变率为85.71%,与文献报道相似。结论LVAS在青年和儿童感音神经性聋中较为常见,运用高分辨率CT进行轴位颞骨扫描并加强临床医师对LVAS的认识,可减少此病的漏诊。SLC26A4 IVS7-2A>G突变筛查可用于新生儿筛查和产前诊断,以减少耳聋患者出生,指导携带致病基因患儿的行为。     

Analysis of p1 latency in normal hearing and profound sensorineural hearing loss

Objectives

P1 is a robust positivity at a latency of 50-150 msec in the auditory evoked potential of young children. It has been reported that over the first 2-3 years of life, there is a rapid decrease of the latency and the mean P1 latency in adults with normal hearing is approximately 60 msec. This study was designed to evaluate the change of the P1 latency in Koreans with normal hearing according to age and to compare this with the P1 latency of young patients with profound sensorineural hearing loss before and/or after cochlear implantation.

Methods

Among the patients who visited the Department of Otorhinolaryngology at Seoul National University Hospital from June 2007 to September 2009, the P1 response was recorded in 53 patients in the normal hearing group, in 13 patients in the pre-cochlear implantation (CI) group and in 10 patients in the post-CI group. A synthesized consonant-vowel syllable /ba/ was used to elicit the evoked responses. The evoked responses were collected using the center of the frontal head. For each subject, an individual grand average waveform was computed by averaging the ten recordings. The P1 latency was visually identified as a robust positivity in the waveform.

Results

For the normal hearing group, the P1 latency showed the pattern of shortening as the age increased (coefficient, -0.758; P<0.001). For the pre-CI group, 10 cases showed delayed latencies and 3 cases did not show the P1 wave. For the post-CI group, the P1 latencies showed a less delayed tendency than those of the pre-CI group, but this was not statistically different.

Conclusion

This report provides the standard value of the P1 latency at each age in Koreans for the first time and the findings support that the maturation of the central auditory pathways could be measured objectively using the P1 latency.     

Delineating the hearing loss in children with enlarged vestibular aqueduct

Objective/Hypothesis: To explore the clinical characteristics and audiologic outcomes in children with enlarged vestibular aqueduct (EVA). Study Design: Retrospective study in a pediatric tertiary care facility. Methods: A total of 54 cases (82 ears) of children with EVA were identified with complete records, including otologic evaluation, imaging studies, and audiologic assessments. The diagnosis of EVA was confirmed by computerized tomography scan/magnetic resonance imaging of the temporal bone. Hearing status was assessed using behavioral testing or auditory brainstem response (ABR). Tympanometry, acoustic reflex, and vestibular evoked myogenic potential (VEMP) testing were also performed when appropriate. Results: Fifty‐two percent of our EVA cases showed bilateral involvement, and 43% of all ears with EVA also had cochlear malformations, such as Mondini dysplasia. Sensorineural HL was initially diagnosed in 16 ears (20% of the total) with EVA whereas conductive or mixed HL was found in 66 ears (80% of the total). Further review of all EVA cases with sensorineural HL showed lack of proper bone conduction testing, so air‐bone gaps were missed. Despite air‐bone gaps in EVA ears, middle ear pressure and mobility were usually normal, along with present acoustic reflexes. VEMP responses were present with abnormally low thresholds. Conclusions: Air‐bone gap(s) can be found in most ears with EVA if both air and bone conduction thresholds are properly tested. Normal tympanometry, presence of acoustic reflex and low threshold VEMP responses suggest that the air‐bone gap in EVA is due to an inner ear anomaly, similar to the “third” labyrinthine window syndrome.     

Detection of cytomegalovirus DNA in preserved umbilical cords from patients with sensorineural hearing loss

We performed a retrospective diagnostic study of congenital cytomegalovirus (CMV) infection in patients with sensorineural hearing loss (SNHL). CMV DNA in preserved umbilical cords was analyzed using real-time polymerase chain reaction analysis. Of 45 analyzable patients with SNHL, CMV DNA was detected in the preserved umbilical cords of 3 patients, all of whom had bilateral SNHL that lacked a clear onset period. CMV DNA was not detected in any of the patients with sudden SNHL or enlarged vestibular aqueduct-associated SNHL. The features of CMV-associated SNHL were more asymmetric than those of CMV-negative bilateral SNHL.     

Epileptiform electroencephalogram abnormality in children with congenital sensorineural hearing loss

Objectives

This work was designed to study electroencephalogram findings in children with congenital sensorineural hearing loss and correlate these findings with the SNHL parameters as duration, etiology, severity, and type.

Methods

Ninety children with bilateral congenital sensorineural hearing loss served as the study group. They were free from any neurological disorders or symptoms that are commonly associated with abnormal electroencephalogram as convulsions or loss of consciousness. Twenty children having normal hearing with no history of otological or neurological disorders served as the control group. All children participating in the study were subjected to full medical and audiological history, otological examination, neurological examination, audiological evaluation and electroencephalogram recording.

Results

Mean age of the children in the control group was 3.56 ± 2.1 years and mean age of the children in the study group was 3.8 ± 2.2 years. While none of the control children had abnormal electroencephalogram, 38 (42.2%) of children with congenital SNHL had epileptiform electroencephalogram abnormality. The epileptiform abnormality was generalized in 14 children (36.8%), focal temporal in 17 children (44.7%) and focal other than temporal in 7 children (18.4%). According to the hemispheric side affected, the abnormality was right in 14 children (36.8%), left in 10 children (26.3%) and bilateral in 14 children (36.8%). No statistically significant predominance of specific site or side of the epileptiform abnormality was found. Similarly, no statistical significant prevalent of the epileptiform abnormality was found in relation to the age or sex of children, duration of hearing loss or etiology of hearing loss (i.e., genetic vs. neonatal insults). On the other hand, the epileptiform abnormality was statistically prevalent in children with moderate degree of hearing loss, and in children with auditory neuropathy spectrum disorder.

Conclusions

The epileptiform electroencephalogram abnormality is a common finding in children with congenital sensorineural hearing loss especially those with auditory neuropathy spectrum disorder, suggesting the affection of the central nervous system despite the absence of neurological symptoms or signs. These findings raise the question of the requirement of medical treatment for those children and the effect of such treatment in their rehabilitation.     

Comparison of auditory steady-state responses and auditory brainstem responses in audiometric assessment of adults with sensorineural hearing loss

Objective

Many of the medico-legal patients who claimed compensation may exaggerate hearing loss that varies in degree, nature, and laterality. The purpose of this study was to investigate whether Auditory Steady-State Response (ASSR) could be used to predict the hearing level of adults, and whether ASSR could become a better testing method than Auditory brainstem response (ABR) in audiometric assessment of adults with sensorineural hearing loss.

Methods

This was a prospective study, which was conducted in a tertiary referral hospital. From January to June 2007, 142 subjects (284 ears) with varying degrees of sensori-neural hearing impairment were included in this study. Four commonly used frequencies (500, 1000, 2000, 4000 Hz) were evaluated. All subjects received pure-tone audiometry, multi-channel ASSR, and ABR tests for threshold measurement. The correlation of pure tone thresholds with ASSR and ABR thresholds were assessed.

Results

Between multi-channel ASSR and pure tone thresholds, a difference of less than 15 dB was found in 71% while a difference of less than 25 dB was found in 89% of patients. The correlation coefficient (r) of multi-channel ASSR and pure tone thresholds were 0.89, 0.95, 0.96, and 0.97 at 500, 1000, 2000, and 4000 Hz, respectively. The strength of the relationship increased with increasing frequency. On the other hand, between ABR and pure-tone thresholds, a difference of less than 15 dB was found in 31%; a difference of less than 25 dB was found in 62% of patients. The r correlation value for ABR and pure tone thresholds was 0.83.

Conclusion

ASSR is a more reliable test for the accurate prediction of auditory thresholds than ABR. It can be a powerful and convenient electro-physiologic examination tool for clinically assessing of adults with sensorineural hearing loss.     

Hearing in the MRL/lpr mouse as a possible model of immune-mediated sensorineural hearing loss

In order to clarify the possible mechanism of hearing loss in immune-mediated sensorineural hearing loss, basic research needed includes animal model studies. In the present investigation, we examined hearing thresholds and cochlear histologies of the MRL/lpr mouse which is now well-known as a model for pathology consistent with systemic lupus erythematosis (SLE). Present findings demonstrated that there were no statistically significant differences in auditory brainstem response (ABR) thresholds between 4- to 6-week-old “young” and 20- to 25-week-old “old” MRL mice. These differences were not sex-dependent. Under light microscopy, there were no abnormal morphological findings in the cochleas of either young or old MRL mice. With immunohistochemistry, mouse IgG was detected around the capillary walls in the stria vascularis in both young and old MRL mice. Serum IgG level of the MRL mice significantly decreased after predonisolone (PSL) administration. However, expression of mouse IgG in the stria vascularis was not observed in the MRL mice after PSL administration. From these results, we speculate that the hearing of the MRL mouse does not always deteriorate, and the deposition of mouse IgG on the capillary wall in the stria vascularis is not a sufficient factor to induce hearing loss. At this point, we conclude that the MRL mouse should not be considered a useful model for immune-mediated sensorineural hearing loss. Received: 22 July 1997 / Accepted: 4 December 1997     

慢性化脓性中耳炎与感音神经性聋的相关性分析

目的：探讨慢性化脓性中耳炎与感音神经性聋之间的相关性。方法：回顾分析174例单侧慢性化脓性中耳炎患者的骨导阈值改变。采用配对t检验分析0．5kHz，1．0kHz，2．0kHz，4．0kHz患耳与健耳骨导阈值的差异，单因素方差分析法分析胆脂瘤存在及听骨链破坏对语频(0．5kHz，1．0kHz，2．0kHz)和4．0kHz骨导阈值的影响，直线回归法讨论了语频和4．0kHz骨导阈值改变与年龄和病程之间的相关性。结果：患耳与健耳各频率骨导阈值之间差异有统计学意义。语频骨导听力损失程度随着患者年龄的增加而逐渐加重。胆脂瘤的存在以及听骨链破坏亦未增加感音神经性聋的发生概率。结论：慢性化脓性中耳炎可引起感音神经性聋。高频骨导听阈较低频更易受到影响。     

Progressive sensorineural hearing loss in children with mitochondrial encephalomyopathies

OBJECTIVE: Mitochondrial disorders are responsible for a variety of neurological syndromes. Specific mitochondrial DNA mutations have been identified recently in some of these rare disorders. Clinical symptoms may occur in different organs to various extent; often they are associated with progressive hearing loss. The aims of this study were to determine incidence, onset, and characteristics of hearing loss in children with mitochondrial encephalomyopathies and to investigate a possible correlation between the degree of hearing loss and neurological symptoms. In addition, we investigated the prognostic value of hearing loss as a predictor of the disease. STUDY DESIGN: From August 1992 to September 1998, 29 patients ranging in age from 5 to 23 years (mean years) were studied. These children were hospitalized for diagnostic purposes in the neuropediatric department. METHODS: The mitochondrial disorder was diagnosed by clinical and laboratory testings, including analysis of the mtDNA. Audiological evaluation consisted of measurements of pure-tone and speech audiometry, tympanometry, and acoustic refle- threshold testing, auditory brainstem response, and evoked as well as distortion-product otoacoustic emissions. RESULTS: A sensorineural hearing loss was identified in 12 children. Three of these were diagnosed as having classic Kearns-Sayre syndrome; five as having multisystem KSS; two as having the syndrome of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); one as having KSS-MELAS overlap syndrome; and one as having Friedreich ataxia. Longitudinal testing was performed in seven children, and in all of them a progression of the hearing loss could be demonstrated. Audiological test results in all 12 children suggested cochlear as well as retrocochlear origin of the hearing loss presenting independently from the severity of hearing impairment. No correlation between the characteristics and degrees of hearing loss and the number and severity of clinical neurological symptoms could be found. CONCLUSIONS: The present study demonstrated a high incidence (42%) of sensorineural hearing loss in children with mitochondrial encephalomyopathies. The progressive nature of the hearing impairment was confirmed by a significant correlation between the duration in years and severity of hearing loss in the children. The hearing loss does not have a prognostic value for the progression of the disorder. Based on our findings, we recommend regular audiometric examinations in patients with mitochondrial disorders.