听神经病和梅尼埃病患者耳蜗电图振幅比与面积比差异分析

目的分析听神经病(Auditory Neuropathy/Auditory Neuropathy Spectrum Disorder, AN/ANSD)与梅尼埃病(Meniere's disease,MD)患者交替短声诱发的耳蜗电图各项参数差异与特征。方法对正常听力对照组10人(20耳)及听神经病19人(38耳)、梅尼埃病16人(单侧14例,双侧2例)行耳蜗电图检查,刺激声为交替短声100dBnH。对照组较AN和MD多做2组强度分别为80、90dBnHL。统计分析应用SPSS(版本25.0),MD组症状耳与非症状耳采取配对t检验;正常对照组、MD组、AN三组对比采取方差分析。数据非正态分布或方差不齐时行非参数检验。结果 MD症状耳与非症状耳、正常对照组与AN、MD的平均听阈均存在统计学差异;正常对照组不同强度100dBnHL与80dBnHL在SP和AP振幅与潜伏期之间有显著性差异;正常对照组、梅尼埃症状耳组、AN三组SP、AP同时引出率分别为100%、100%、87%。MD组14耳症状耳与非症状耳仅SP振幅与SP/AP振幅比有显著性差异;正常对照组、AN组、MD三组比较,除外SP振幅,其余参数均有显著统计学差异(P <0.05)。以正常对照组SP/AP振幅比95%置信区间上限0.31,SP/AP面积比上限1.47,MD症状耳阳性率振幅比、面积比均为83.33%,非症状耳振幅比及面积比阳性率分别为35.71%及57.14%;AN振幅比及面积比阳性率均为100%。结论 AN与MD患者振幅比和面积比的比值均增高,其差异源于AN患者AP振幅异常降低或消失;MD患者在高强度刺激时AP振幅随听力损失降低但SP振幅不变或增高。ECochG辅助诊断单侧MD自身对照更有意义;SP/AP振幅比、面积比是辅助诊断梅尼埃病和听神经病的有效手段。     

外耳道耳蜗电图对梅尼埃病患者的诊断价值

目的 探讨外耳道耳蜗电图对于梅尼埃病患者的诊断价值。 方法 对确诊梅尼埃病的58例患者(60耳),采用外耳道铜箔片电极完成耳蜗电图检查。采集患者的病例信息、耳蜗电图检查结果、纯音测听及内耳膜迷路MRI钆造影结果,同时招募40例正常志愿者做外耳道耳蜗电图检查对照。评估耳蜗电图检出率、总和电位(SP)和听神经动作电位(AP)的振幅比(SP/AP)、两者面积比(Asp/Aap)、潜伏期及各波时长,其中Asp/Aap采用改进后的计算方式。采用t检验及Mann-Whitney U检验分析比较梅尼埃病患耳与单侧罹患者对侧耳及正常对照耳之间各参数指标的差异。分析Asp/Aap与患者病程、发病频率、听力分期及MRI显示的积水程度的相关性。 结果 60耳中46耳引出耳蜗电图(76.67%),单侧罹患者对侧耳及正常对照均引出。使用受试者工作特征曲线(ROC)得出外耳道耳蜗电图SP/AP及Asp/Aap的最佳截点分别为0.38及2.42,SP/AP曲线下面积(AUC)为0.920,而Asp/Aap的AUC为0.985,说明使用面积比的诊断价值更高。患耳SP/AP、Asp/Aap及SP时长较单侧罹患者对侧耳及正常对照耳显著升高,患耳SP/AP与疾病病程及分期相关,SP/AP、Asp/Aap均与MRI显示的耳蜗积水程度相关,而前庭积水程度仅与Asp/Aap相关。 结论 外耳道电极耳蜗电图的振幅比及面积比均在一定程度上反映病程及内耳积水程度。外耳道耳蜗电图对梅尼埃病的临床诊断有一定辅助意义。     

不同听力检测方法甘油试验的结果比较

目的比较纯音测听甘油试验、耳蜗电图甘油试验、畸变产物耳声发射(DPOAE)甘油试验对梅尼埃病的诊断价值。方法选择63例梅尼埃病和63例非梅尼埃病眩晕患者,分为A、B、C三组,每组包括21例梅尼埃病患者和21例非梅尼埃病眩晕患者,在服用甘油前和服用甘油后1、2、3h分别观察三组患者纯音测听(A组)、耳蜗电图(B组)和DPOAE(C组)的变化,比较三组间甘油试验阳性率。结果 A组梅尼埃病患者纯音测听甘油试验阳性率最高为38.10%(18/21),B组耳蜗电图甘油试验阳性率最高为52.38%(11/21),C组DPOAE甘油试验阳性率最高为57.14%(12/21)。结论耳蜗电图和DPOAE的甘油试验较纯音测听的甘油试验更为准确,能在一定程度上提高对梅尼埃病的诊断率。     

耳蜗电图在梅尼埃病诊断中的价值

迄今尚缺乏诊断梅尼埃病的敏感且特异的客观试验，７０年代以来，若干研究探讨了耳蜗电图（Ｅｌｅｃｔｒｏｃｏｃｈｌｅｏｇｒａｍ，ＥＣｏｃｈＧ）在梅尼埃病诊断中的价值，认为典型的改变是－ＳＰ异常增大，导致－ＳＰ／ＡＰ比值增高，以及－ＳＰ－ＡＰ复合波形异常增宽。各家报告－ＳＰ／ＡＰ诊断梅尼埃病阳性率从３２％至８７％．本文报告了９７例１００耳梅尼埃病鼓室内法检测的耳蜗电图结果，４９例－ＳＰ／ＡＰ比值异常增高，阳性率４９％；波型异常增宽１７耳，总阳性率６６％．眼震电图检测的阳性率６１％．耳蜗电图和眼震电图改变一致的４３耳，二者总阳性率为８４％。对各家阳性率不一致的原因作了分析。认为耳蜗电图－ＳＰ／ＡＰ比值诊断梅尼埃病的敏感性不如文献报告的那么乐观，在目前尚无更敏感更特异的诊断手段的情况下，耳蜗电图和眼震电图在梅尼埃病的诊断中起着相互印证和相互补充的作用。     

单侧梅尼埃病患者双侧耳蜗电图检查的意义

目的分析梅尼埃病患者双侧耳蜗电图,以早期发现一侧梅尼埃病对侧耳膜迷路积水的可能性,了解梅尼埃病患者对侧无症状耳内淋巴积水可能的发生率。方法对明确诊断为梅尼埃病的121例患者行双侧耳蜗电图检查,对其中可统计出明确病程的114例比较其双侧耳蜗电图结果与病程的关系。结果可以统计出梅尼埃病病程的114例中,单侧异常46例,平均病程7.42±7.68年(5天~37年);双侧异常38例,平均病程5.43±5.73年(3个月~20年);双侧正常者30例,平均病程5.37±4.40年(4个月~12年)。三种情况下,病程与耳蜗电图结果无直线相关(P>0.05)。在121例行双侧耳蜗电图检查的病例中,双侧耳蜗电图异常者39例,其中9例有双侧耳鸣,占23.1%(9/39),而单侧耳蜗电图异常者51例中,出现双侧耳鸣的仅有1例,占2%(1/51),双侧耳蜗电图异常伴双侧耳鸣的发生率明显高于单侧耳蜗电图异常伴双侧耳鸣的发生率(P<0.01)。结论耳蜗电图对梅尼埃病诊断的评价应建立在对梅尼埃病动态变化的理解基础之上;耳蜗电图对早期听力正常的梅尼埃病的诊断具有一定的参考价值。     

梅尼埃病耳蜗电图临床研究

梅尼埃病的耳蜗电图(EcochG)检查常出现高振幅的 SP 和服脱水剂后 SP/AP 比值的改变。本文报导的目的为:①病人接受高渗利尿剂后观察 SP/AP 是否变化;②内淋巴减压术后监测 SP/AP 的变化对观察梅尼埃病的进展是否有意义。共对8组受检者进行分析:①正常人29耳;②梅尼埃病168耳,③可疑梅尼埃病85     

高通滤过噪声掩蔽听觉脑干诱发电位的临床应用

目的 确立正常年轻人高通滤过噪音掩蔽脑干听觉诱发电位V波潜伏期的正常值,比较高通滤过噪声掩蔽脑干听觉诱发电位在正常人组、非梅尼埃病性感音神经性听力损失患者组和梅尼埃病患者的差别.方法 30例听力正常的本校大学生,20例非梅尼埃病性感音神经性听力损失患者和20例梅尼埃病患者,均行高通滤过噪音掩蔽脑干听觉诱发电位(分别检测8kHz、4kHz、2kHz、lkHz、500Hz以下频率,刺激声强度为60dBnHL)和纯音测听测试,2个疾病组患者加行耳蜗电图检查.结果 正常人组和非梅尼埃病组感音神经性听力损失患者的V波潜伏期随刺激频率段的下降而逐渐延长,△V均值2.28ms,最大3.65ms,最小0.45ms,振幅逐渐下降,波形变宽.而梅尼埃病患者V波潜伏期延长不明显,△V最小-0.14ms,最大0.6ms,△V均值0.32ms.结论 正常年轻人高通滤过噪音掩蔽ABRV波的潜伏期正常值的建立,为听觉疾病的诊断提供了客观参考.高通滤过噪音掩蔽脑干听觉诱发电位对梅尼埃病和非梅尼埃病的感音神经性听力损失的诊断敏感性和特异性均达95%以上,明显优于耳蜗电图.     

三维液体衰减反转恢复序列磁共振成像在内耳疾病中的应用研究

 目的探讨三维液体衰减反转恢复序列磁共振成像(3D FLAIR MRI)在内耳疾病诊断中的应用。方法选择我院52例内耳疾病患者作为研究对象,将其分为研究组（梅尼埃病患耳组、可疑梅尼埃病患耳组和突发性聋患耳组）和对照组（健侧耳组）,对受试者进行耳蜗电图及内耳3D FLAIR MRI扫描等相关检查,观察各组内耳3D FLAIR MRI内淋巴显像与耳蜗电图关系。结果3D FLAIR MRI扫描可观察到梅尼埃病组、可疑梅尼埃病组、突聋组内淋巴积水程度患侧比健侧耳组严重,但梅尼埃病、可疑梅尼埃病及突发性聋的内淋巴积水程度差异无统计学意义。内淋巴积水诊断的阳性率3D FLAIR MRI扫描高于耳蜗电图,尤其在可疑梅尼埃病的诊断中3D FLAIR MRI 检查比耳蜗电图更具有优势,但尚不能认为3D FLAIR MRI扫描可以取代耳蜗电图检查。结论三维液体衰减反转恢复序列磁共振成像在内耳疾病诊断中的应用效果显著,可以用于梅尼埃病、可疑梅尼埃病及突聋的辅助诊断,能有效提高内耳内淋巴积水的检出率。     

梅尼埃病患者耳蜗电图描记与冷热试验结果的关系

负和电位增大常见于梅尼埃病患者,但关于耳蜗电图描记与冷热试验结果关系的研究很少。作者对35例单侧梅尼埃病患者进行耳蜗电图描记和定量冷热试验检查。应用鼓膜外电极耳蜗电图描记法,负和电位与动作电位振幅之比>0.43时,判为负和电位增大。以30℃冷水和     

听力学检测和内耳磁共振成像在梅尼埃病诊断中的作用

目的探讨多种临床检测方法在梅尼埃病诊断中的应用价值方法回顾性分析2012年1月至2015年12月确诊为梅尼埃病的77例患者的病历资料,分析梅尼埃病患者的听力学检查以及磁共振水成像检查结果。结果共69例纯音测听结果异常(异常率92.3%);接受前庭诱发肌源性电位检测者65例,异常37例,异常率56.9%;接受耳蜗电图检测者22例,结果异常者15例(异常率68.2%);接受冷热气试验者71例,两侧对称比异常者47例,双侧低下者2例,异常率69.0%;接受甘油试验者12例,试验阳性者3例,异常率25.0%;接受磁共振造影者76例,迷路积水者70例,异常率92.1%。结论纯音测听和磁共振造影在梅尼埃病患者中阳性率高,冷热气试验及耳蜗电图假阳性率次之,可作为梅尼埃病观察的参考指标。     

梅尼埃病听力损失程度和类型对短声诱发的SP/AP比值的影响

目的 :探讨耳蜗电图 (ECoch G)在梅尼埃病诊断中听力损失程度和类型 ,对交替短声诱发的负性总和电位 (SP)与动作电位 (AP)比值 (SP/ AP)的影响。方法 :采用鼓膜电极耳蜗电图描记术 ,对梅尼埃病 90耳 (梅尼埃病组 )和其他原因感音神经性聋 6 0耳 (感音神经性聋组 )及正常听力 5 0耳 (正常对照组 )记录了 AP和 SP各参数 ,对结果进行对照分析。结果 :AP潜伏期 3组差异无显著性 ,AP振幅正常对照组高于梅尼埃病组和感音神经性聋组 (P <0 .0 5 ) ,SP振幅正常对照组高于感音神经性聋组 (P <0 .0 1)而低于梅尼埃病组 (P <0 .0 1)。SP/ AP振幅比值梅尼埃病组 (48.0 9± 14 .38) % ,明显高于感音神经性聋组 (2 0 .0 2± 15 .0 0 ) %和正常对照组 (2 3.85±8.0 5 ) % ,(均 P <0 .0 1)。梅尼埃病组 SP/ AP比值与主观纯音听阈呈正相关 (r =0 .5 6 0 1,P <0 .0 1) ,其异常率为 73%。梅尼埃病不同听力损失组中 ,SP/ AP比值轻度耳聋组低于中度和中重度组 (均 P <0 .0 1) ,后两组差异无显著性意义 (P >0 .0 5 )。低频型低于平坦型 (P <0 .0 5 ) ,高频型和前两型相比差异无显著性意义。结论 :SP/ AP振幅比值异常增大有助于梅尼埃病的临床诊断 ,在一定范围内随听阈提高而增大 ,必须有足够的残余听力才能记录质量好的图形。     

梅尼埃病耳蜗及前庭功能损害程度的相关性研究

目的探讨梅尼埃病耳蜗与前庭功能损害程度的相关性及不同程度病变的临床特征。方法对符合诊断标准的44例梅尼埃病患者进行纯音测听、畸变产物耳声发射、Metz重振试验、听性脑干反应(ABR)、耳蜗电图(ECochG)、甘油试验等听力学检查及双温试验、Fukuda踏步试验等前庭功能检查。将测试结果用耳蜗与前庭功能损害的综合评价函数进行评价,同时根据0.5、1、2kHz平均听阈,将病例分成I组6例(平均听阈<25dBHL)、Ⅱ组13例(平均听阈25～40dBHL)、Ⅲ组25例(平均听阈41～70dBHL)。结果Ⅰ、Ⅱ、Ⅲ组-SP/AP阳性率和CP异常率呈上升趋势,各组间差异有统计学意义(P<0.05)。半规管功能异常者(25例)中纯音听阈值、-SP/AP值和耳蜗电图阳性率明显高于半规管功能正常者(19例)(P<0.05)。ECochG阳性者(28例)Metz重振试验、甘油试验阳性率显著高于ECochG阴性者(16例)(P<0.05)。耳蜗功能损害的综合评价函数为f1=0.212Ⅹ11+0.259Ⅹ12+0.429Ⅹ13+0.367Ⅹ14,前庭功能损害的综合评价函数为f2=0.275Ⅹ21+0.375Ⅹ22+0.398Ⅹ23+0.119Ⅹ24,综合评价函数f1与f2呈正相关性(r=0.395,P<0.05)。结论梅尼埃病耳蜗功能与前庭功能损害程度呈较弱正相关性,运用主成分分析法构建的综合评价模型可以较全面综合原始变量信息,合理反映耳蜗和前庭功能损伤程度,为疾病诊断、治疗选择和疗效评价提供依据。     

Electrocochleography in the diagnosis of Meniere's disease

This study prospectively analyses electrocochleography (ECoG) recordings obtained from ears demonstrating symptoms highly suggestive of Meniere's disease. Comparison is made with ECoG recording from ears in which the diagnosis of Meniere's is considered unlikely (control ears). Electrocochleograph recordings were made through a transtympanic recording needle, situated in the round window niche. Analysis was made of the 1 kHz tone burst summation potential (SP) and the summation potential:action potential (SP/AP) ratio response to a 90 dB click. All patients were prospectively awarded a Meniere's score based on a 10-point scale, and comparison was made between ears awarded a score of 7 or greater (Meniere's ears; n > 500), and ears awarded a score 3 or less (control ears; n > 900). Results demonstrate a significant difference in the 1 kHz SP response, and the SP/AP ratio, between "control" and "Meniere's" ears. Furthermore, we show that SP negativity is proportional to the amplitude of the AP click response, and in patients producing an AP click amplitude exceeding 10 V, sensitivity of the tone burst test approaches 85%. This study provides further evidence suggesting the useful role of electrocochleography in determining a diagnosis of endolymphatic hydrops. and demonstrates improved sensitivity of the 1 kHz SP response, compared with SP/AP click ratio, in the diagnosis of Meniere's disease.     

Augmentation of vestibular evoked myogenic potentials: an indication for distended saccular hydrops

OBJECTIVE/HYPOTHESIS: Vestibular evoked myogenic potential (VEMP) testing has become a well-established test to explore the sacculo-collic pathways in human. The aim of the present study is to establish a clinical indication for saccular hydrops by VEMP testing. STUDY DESIGN: Prospective study. METHODS: Ten patients (three men and seven women) with Meniere's disease and 10 patients (four men and six women) with sudden deafness were admitted and given pure-tone audiometry and VEMP testing daily. Interaural amplitude difference over the sum of amplitudes of both ears was measured, and when the ratio exceeded 0.36, the test result was coined "augmented VEMP." RESULTS: During admission, three hydropic ears presented with augmented VEMP test results, with increased interaural amplitude difference ratio (mean difference ratio, 0.40+/-0.03). Seven hydropic ears had steady VEMP test results, with a mean interaural amplitude difference ratio of 0.15+/-0.07. Compared with the normal control ears, all had steady VEMP test results, with a mean interaural amplitude difference ratio of 0.14+/-0.11, which is significantly different from the hydropic ears with augmented VEMP test results (P <.05). In another 10 patients with sudden deafness, all had positive steady VEMP test results, with their mean interaural amplitude difference ratio of 0.14+/-0.12, which is similar to that in the control ears. CONCLUSIONS: Augmented VEMP test results are an indication of distended saccular hydrops, whose distended wall is in contact with the footplate. VEMP testing may be beneficial in differentiating the initial stage of Meniere's disease and sudden deafness.     

梅尼埃病的球囊功能

目的 :通过记录、分析梅尼埃病患者的前庭诱发的肌源性电位 (VEMP) ,了解球囊的功能。方法 :15例确诊为梅尼埃病的患者行VEMP检查 ,分析梅尼埃病VEMP的不同表现形式 ,并将该结果与冷热试验结果比较。结果 :正常双侧短声刺激p13波和n2 3波出现率为 10 0 % ,梅尼埃病受试者VEMP 30 %不能正常引出 ,有 3种表现形式 :VEMP双侧无反应、患侧反应振幅正常和VEMP患侧反应低振幅。结论 :梅尼埃病患者膜迷路积液可影响球囊功能 ,VEMP检查有助于梅尼埃病的诊断     

Glycerol affects vestibular evoked myogenic potentials in Meniere's disease

OBJECTIVES: to show that abnormal vestibular evoked myogenic potentials on the sternocleidomastoid muscle (SCM) in patients with unilateral Meniere's disease are caused by endolymphatic hydrops. Subjects: six normal volunteers and 17 patients with unilateral Meniere's disease were examined. METHODS: click-evoked myogenic potentials were recorded with surface electrodes over each SCM. Responses evoked by clicks recorded after oral administration of glycerol (1.3 g/kg body weight) were compared with those recorded before administration. RESULTS: the change rate of the p13-n23 amplitude was calculated. The mean+standard deviation (S.D.) of the change rate was 3.52+14.6% in normal subjects. On the unaffected side of patients the change rates were within the normal range (within the mean+/-2S.D.) in 13 patients, and three ears showed significant decrease. Only one ear showed significant increase. On the affected side, five ears showed significant increase of the amplitude while two ears showed significant decrease after oral administration of glycerol. Effects on evoked myogenic potentials were independent of those on pure tone hearing. CONCLUSION: vestibular evoked myogenic potentials in some patients with unilateral Meniere's disease were improved by oral administration of glycerol. This result suggests that abnormal vestibular evoked myogenic potentials in patients with unilateral Meniere's disease could result from endolymphatic hydrops.     

An electrocochleographic study of acute low-tone sensorineural hearing loss

Summary Twenty-four patients with acute low-tone sensorineural hearing loss (ALHL) were examined using electrocochleography. The negative summating potential (SP) amplitude and the summating potential/action potential (AP) ratio were significantly greater in the ALHL patients than in normals. The SP/AP ratio was smaller in the ALHL patients than in patients with known Meniere's disease and moderate hearing loss, although the SP amplitude was somewhat greater in the former. An abnormal increase in the SP amplitude following click stimuli was found in 54% of the ALHL patients, while the SP/AP ratio was increased abnormally in 63% of these patients. These findings suggest that the pathophysiology of ALHL may be similar to that for endolymphatic hydrops.     

External aperture of the vestibular aqueduct in Meniere's disease

OBJECTIVE: To study the relationship of the length of the external aperture of the vestibular aqueduct and the ratio of the summating potential and action potential (SP:AP) in patients with Meniere's disease. STUDY DESIGN: Retrospective case study. SETTING: Neurotology referral center. PATIENTS: Fifty-four patients with Meniere's disease and nine control subjects without Meniere's disease. INTERVENTION: The external aperture of the vestibular aqueduct was measured from a three-dimensional surface reconstruction computed tomography scan. Transtympanic electrocochleography was performed on patients with Meniere's disease. MAIN OUTCOME MEASURE: The length of the external aperture of the vestibular aqueduct in the Meniere's disease ears was related to the SP:AP ratio in the Meniere's disease ears and compared with controls. RESULTS: The average length of the external aperture was 3.79 +/- 2.92 mm in Meniere's disease ears and 5.35 +/- 1.73 mm in the control ears (p < 0.05). An enlarged SP:AP ratio was found in 95% of ears in the group with nonvisible external apertures of the vestibular aqueduct, 91% of ears in the <5 mm group, 58% of ears in the 5-7 mm group, and 29% of ears in the >7 mm group (chi-square = 24.814; p = 0.000). CONCLUSIONS: The length of the external aperture of the vestibular aqueduct in patients with Meniere's disease is significantly shorter than in those without Meniere's disease. Endolymphatic hydrops, evidenced by an enlarged SP:AP ratio, was related to the length of the external aperture of the vestibular aqueduct. The shorter the external aperture, the more often the SP:AP ratio was enlarged. A short or nonvisible external aperture of the vestibular aqueduct is a predisposing factor to the development of Meniere's disease.     

Clinical study of elderly patients with Meniere's and related diseases

In order to study the characteristics of elderly patients (70 or over at onset) with endolymphatic hydrops disorders, we selected six patients with Meniere's disease (MD), five patients with delayed endolymphatic hydrops (DEH), and two patients with syphilis of the labyrinth (SL) from 7112 patients who had visited the Neurotological Clinic of the Toyama Medical and Pharmaceutical University Hospital during 1979-1998. Clinical features were characterized as follows: (1) Since 1990, the proportion of elderly patients increased as lifespans lengthened. (2) A narrow fluctuation in hearing, low positive rate on glycerol test, high positive rate of dominant-SP in EcochG, and the moderate abnormal rate of the oculomotor system tests were found. (3) The prognosis was relatively good. From these neurotological observations, it could be concluded that elderly patients with endolymphatic hydrops disorders were characterized by the multipathological finding of the endolymphatic hydrops and the complications of CNS disorders.     

Can electrocochleography in Meniere's disease be noninvasive?

OBJECTIVES: To evaluate and compare the results of extratympanic and transtympanic electrocochleography (ECochg) in clinically diagnosed cases of Meniere's disease and controls. DESIGN: Prospective study on 20 clinically diagnosed cases of Meniere's disease and 20 age- and sex-matched controls. SETTING: Department of Otolaryngology, Head and Neck Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India. METHODS: Electrocochleography was performed by a transtympanic method using a stainless steel needle electrode kept on the promontory and by an extratympanic method whereby the needle electrode was inserted into bony canal skin. MAIN OUTCOME MEASURES: The various parameters compared were summation potential latency and amplitude, action potential latency and amplitude, and ratio of summation to action potential amplitude (SP/AP). RESULTS: A significant difference in summation to action potential amplitude ratio (SP/AP) between cases and controls was obtained by both methods. Using 0.29 as a cutoff for SP/AP, the transtympanic method yielded a sensitivity of 100% and a specificity of 90%, whereas the extratympanic method showed corresponding values of 90% and 80%, respectively. CONCLUSION: Contrary to previous studies, extratympanic ECochg is shown to be an efficacious and a less invasive test as compared with the transtympanic method and can be easily performed in clinical practice.