Analysis of wideband tympanometry in Ménière's disease / Análise da timpanometria de banda larga na doença de Ménière

Abstract Introduction: Endolymphatic hydrops is the pathophysiological substrate of Ménière's disease. The changes in the inner ear, transmitted to the middle ear through changes in the ossicular chain mobility, can be quantified by wideband tympanometry, through the measurement of the acoustic absorbance at multiple frequencies, represented by the sound energy absorbed by the middle ear, even at its early stages. Studying the behavior of the middle ear through the absorbance in patients with endolymphatic hydrops under ambient pressure and under peak pressure can be useful for detecting Ménière's disease. Objective: To characterize acoustic absorbance behavior in subjects with symptomatic and asymptomatic Ménière's disease compared to controls, in order to verify the ability of wideband tympanometry to detect Ménière's disease. Methods: We carried out a cross-sectional study with a diagnostic approach comparing the findings of wideband tympanometry at ambient pressure and peak pressure between the ears of the control group (n = 30), the asymptomatic group (n = 21) and the symptomatic group (n = 9). Results: Different peak pressure values were found between the ears of the control group (0daPa), the asymptomatic group (−11 daPa) and the symptomatic group (−192 daPa), with p < 0.05 by the Kruskal-Wallis test, Mann Whitney test and Bonferroni correction. Different absorbance values were found between the ears of the symptomatic group and the asymptomatic group compared to the control group for low frequencies at ambient pressure and peak pressure, with p < 0.05 by the Kruskal-Wallis test, Mann Whitney test and Bonferroni correction. Conclusions: The Wideband Tympanometry test was capable of identifying the presence of Ménières disease, and to differentiate between asymptomatic and symptomatic patients, when comparing them with healthy individuals.

Resumo Introdução: A hidropsia endolinfática é o substrato fisiopatológico da doença de Ménière. As alterações desencadeadas na orelha interna, transmitidas à orelha média pelas modificações na mobilidade da cadeia ossicular, podem ser quantificadas pela timpanometria de banda larga, através da medida da absorvância acústica sob múltiplas frequências, representadas pela energia sonora absorvida pela orelha média, mesmo em estágios iniciais de sua instalação. Estudar o comportamento da orelha média através da absorvância em pacientes com hidropisia endolinfática sob pressão ambiente e sob o pico de pressão pode ser útil na detecção da doença de Ménière. Objetivo: Caracterizar o comportamento da absorvância em indivíduos com diagnóstico da doença de Ménière sintomáticos e assintomáticos, comparados com controles, a fim de verificar a capacidade da timpanometria de banda larga em detectar variações clínicas relacionadas a possível hidropisia endolinfática. Método: Foi realizado um estudo transversal, com enfoque diagnóstico, que comparou os achados da timpanometria de banda larga na pressão ambiente e no pico de pressão entre orelhas do grupo controle (n = 30), grupo assintomático (n = 21) e grupo sintomático (n = 9). Resultados: Foram encontrados valores do pico de pressão diferentes entre orelhas do grupo controle (0 daPa), do grupo assintomático (-11 daPa) e do grupo sintomático (-192 daPa), com p <0,05 pelos testes de Kruskal-Wallis, Mann Whitney e correção de Bonferroni. Foram encontrados valores de absorvância diferentes entre orelhas do grupo sintomático e do grupo assintomático em relação ao grupo controle para as frequências baixas na pressão ambiente e na pressão de pico, com p < 0,05 pelos testes de Kruskal-Wallis, Mann Whitney e correção de Bonferroni. Conclusão: A timpanometria de banda larga foi um teste capaz de identificar a presença da doença de Ménière e de diferenciar os pacientes assintomáticos e sintomáticos, comparando-os com indivíduos hígidos.

Emissões otoacústicas evocadas na doença de Ménière / Otoacoustic emissions evoked in Ménière's disease

RESUMO Objetivo Verificar as respostas das emissões otoacústicas (EOA) evocadas por estímulo transiente e produto de distorção em indivíduos com doença de Ménière. Métodos Estudo transversal com casuística composta por 60 indivíduos de 19 a 75 anos de idade, distribuídos em dois grupos: grupo estudo, com 32 indivíduos com diagnóstico médico de doença de Ménière, sem outros riscos, e grupo controle formado por 28 indivíduos com perda coclear, sem doença de Ménière, pareado por idade e gênero ao grupo estudo. Critério de elegibilidade: curva tipo A, sem perda condutiva ou mista ou suspeita de alteração retrococlear. A avaliação audiológica foi composta por anamnese, inspeção do meato acústico externo, audiometria tonal limiar, logoaudiometria, medidas de imitância acústica e emissões otoacústicas evocadas por estímulo transiente e produto de distorção. Resultados Os indivíduos com Ménière apresentaram maior ocorrência de perda unilateral, zumbido pitch grave, vertigem e plenitude auricular em relação ao controle. Nesses indivíduos, houve maior incompatibilidade entre os resultados das EOA e da audiometria tonal: nas perdas unilaterais, observaram-se alterações nas EOA nas orelhas com limiares auditivos normais do lado contralateral, caracterizando disfunções cocleares. Nas orelhas com perda coclear, houve presença de EOAT (por estímulo transiente) e ausência de EOAPD (produto de distorção), contrapondo-se ao grupo controle, que apresentou ausência de EOAT e de EOAPD, como o esperado em perdas cocleares de outras etiologias. Conclusão A pesquisa das emissões na doença de Ménière identificou disfunção coclear na orelha contralateral nos casos unilaterais e presença de EOAT com ausência de EOAPD nas orelhas com perda auditiva, diferenciando-se das perdas cocleares de outras etiologias.

ABSTRACT Purpose To verify the responses of Evoked Otoacoustic Emissions by transient stimulus and distortion product in individuals with Ménière's Disease. Methods Cross-sectional study with a sample composed of 60 individuals, aged 19 to 75 years, divided into two groups: study group, with 32 individuals with a medical diagnosis of Ménière's disease, without other risks and a control group formed by 28 individuals with cochlear loss without Meniere's disease, age and sex matched to the study group. Eligibility criteria: type A curve, without conductive or mixed loss or suspected retrocochlear alteration. The audiological evaluation consisted of anamnesis, inspection of the external acoustic meatus, pure tone audiometry, logoaudiometry, measures of acoustic immittance and transient evoked otoacoustic emissions and distortion product. Results Individuals with Ménière's disease had a higher occurrence of unilateral hearing loss, low pitch tinnitus, vertigo and ear fullness in relation to the control. In these individuals, there was greater incompatibility between the results of OAE and pure tone audiometry: in unilateral hearing loss, alterations in OAE were observed in ears with normal hearing thresholds on the contralateral side, characterizing cochlear dysfunctions. In the ears with cochlear loss, there was the presence of TEOAE and absence of DPOAE, in contrast to the control group, which showed the absence of TEOAE and DPOAE, as expected in cochlear losses of other etiologies. Conclusion The investigation of emissions in Ménière's disease identified cochlear dysfunction in the contralateral ear in unilateral cases and the presence of TOAE with absence of DPOAE in ears with hearing loss, differentiating from cochlear losses of other etiologies.

Clinical features of vestibular syncope associated with tumarkin attacks in delayed endolymphatic hydrops / 中华耳鼻咽喉头颈外科杂志

Objective: To analyze the clinical characteristics of vestibular syncope (VS) associated with drop attacks (DA) in delayed endolymphatic hydrops (DEH). Methods: DEH cases with complete data were retrospectively analyzed, including three DEH cases with DA and VS (VS group), and six DEH cases without DA or VS (control group). The clinical profile, the results of neurotological examinations [such as pure tone audiometry, electrocochleography (EcochG), caloric test, vestibular evoked myogenic potentials (VEMP), and video head impulse test (vHIT)] and treatment outcomes were analyzed. Results: (1) In the VS group, there were three cases of ipsilateral DEH; in the control group, there were six cases of ipsilateral type. One case in each group had a history of migraine. (2) The prevalence of abnormal results in caloric test, vHIT, cervical VEMP, and ocular VEMP in the VS group was 3/3, 1/3, 2/2, and 2/2, respectively, and in the control group was 3/6, 0/3, 1/6, and 4/6, respectively. Two cases in each group underwent EcochG, and no identifiable waveform was elicited on the affected side, and-SP/AP ratio of unaffected side was less than 0.4. (3) Patients in both groups were initially treated with conservative medication. Two cases in the VS group subsequently received intratympanic injections of dexamethasone. No DA or VS occurred during a follow-up period lasting over one year. All patients achieved good control of vertigo during the follow-up period. Conclusions: VS may occur in the patients with DEH. The differential diagnosis of syncope in patients with otogenic vertiginous disease can help improve clinical diagnosis and treatment.

Frequency characteristics of horizontal semicircular canals damage and the ultrastructure analysis of crista ampullaris in patients with Meniere's disease / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the frequency characteristics and the pathological characteristics of the horizontal crista ampullaris in patients with Meniere's disease,and to analyse its structural basis. Methods: Between March, 2019 and November, 2019, seventy-two patients diagnosed as Meniere's disease (27 males and 45 females, aged from 13 to 74 years, with a course of disease ranging from 4 months to 32 years)in Shandong Provincial ENT Hospital were included.Caloric test, sinusoidal harmonic acceleration test (SHA), video-head impulse test (v-HIT), Gadolinium-enhanced inner-ear 3D-FLAIR MRI and pure tone audiometry were conducted in the patients. The function of the horizontal semicircular canal in these patients were analysed as well as its relationship with the degree of endolymphatic hydrops,clinical stage and duration. Light microscopy and transmission electron microscopy were used to observe the ultrastructure of horizontal semicircular canal crista ampullaris from six patients with refractory Meniere's disease who underwent labyrinthectomy. The number of type Ⅰ and type Ⅱ vestibular hair cells, the common pathophysiological changes of horizontal semicircular canal crista ampullaris were investigated in these patients. Statistical analysis was performed using SPSS 19.0. Results: With the increase of detection frequency, the abnormal rate decreased gradually. The abnormal rate of caloric test was 69.4% (50/72), SHA 51.4% (37/72), V-HIT 36.1% (26/72), comparation of the positive rate among the three tests showed statistically significant differences(P<0.05).Neither caloric test nor SHA had correlation with the degree of hydrops(P>0.05), but v-HIT(r=0.434,P<0.01).There was correlation with clinical stage to SHA and v-HIT(r=0.338,0.462,P<0.01), except caloric test(P>0.05).No significant relation was found with caloric test, SHA, v-HIT and course of disease(P>0.05).Morphological observation found abnormal monolayer epithelialization of the horizontal semicircular canal crista ampullaris significantly decreased number of type Ⅱ hair cells compared with type Ⅰhair cells. Hair cells showed perinuclear vacuolization, cytoplasmic vacuoles, mitochondrial electron density increasement and loss of stereocilia. Conclusions: The horizontal semicircular canal damage in the patients with Meniere's disease has a frequency-dependent characteristic, mainly occurres in low frequency area. With progress of the disease, the high frequency area of ampulla will be impaired gradually, and it is related to the degree of endolymphatic hydrops and hearing level. Hair cell injury would be observed,the frequency characteristics may be more associated with the disorder of type Ⅱ hair cells.

Gadolinium-enhanced MRI reveals dynamic development of endolymphatic hydrops in Ménières disease / Ressonância magnética com gadolínio revela o desenvolvimento dinâmico da hidropsia endolinfática na doença de Ménière

Abstract Introduction: Meniere's disease is associated with impaired hearing, tinnitus, vertigo, and aural fullness. Many anatomical studies have suggested idiopathic endolymphatic hydrops as the pathological basis of Meniere's disease, which now can be visualized by using gadolinium -enhanced magnetic resonance imaging of the inner ear. Objective: To investigate the development of endolymphatic hydrops in Meniere's disease by monitoring the vestibules and cochleae of affected patients. Methods: Inner ears of 178 patients with definite unilateral Meniere's disease diagnosis were visualized by 3-dimensional fluid-attenuated inversion recovery and three-dimensional real inversion recovery magnetic resonance imaging following bilateral gadolinium intratympanic injection. The scans were used to evaluate the presence and degree of endolymphatic hydrops in the vestibules and cochlear structures, including the cochlear apical turn, the cochlear middle turn, and the cochlear basal turn. The correlation of endolymphatic hydrops occurrence between the various parts of the inner ear was determined. Results: Symptomatic endolymphatic hydrops was detected on the affected side in all patients, whereas asymptomatic endolymphatic hydrops was detected on the unaffected contra-lateral side in 32 patients (18.0%). On the affected side, the cochlear apical turn and the cochlear middle turn demonstrated significantly higher rates of endolymphatic hydrops than the cochlear basal turn and the vestibule. The severity of endolymphatic hydrops gradually decreased from the cochlear apical turn to the cochlear basal turn. On the contra lateral side, the incidence and degree of the detected asymptomatic endolymphatic hydrops were significantly greater in the cochleae than in the vestibules (p < 0.05), with no significant difference detected between the cochlear turns. Conclusion: Progression of endolymphatic hydrops appears to be directional, initiated in the cochlea. The order of endolymphatic hydrops severity gradually decreases from the cochlear apical turn to the cochlear basal turn and then to the vestibule. Endolymphatic hydrops in the vestibule is associated with symptomatic Meniere's disease.

Resumo Introdução: A doença de Ménière está associada a deficiência auditiva, zumbido, vertigem e plenitude auricular. Muitos estudos anatômicos sugerem hidropsia endolinfática idiopática como a base patológica da doença, que agora pode ser visualizada através de estudo por imagem da orelha interna por ressonância magnética com gadolínio. Objetivo: Investigar o desenvolvimento da hidropsia endolinfática na doença de Ménière com monitoramento dos vestíbulos e das cócleas dos pacientes afetados. Métodos: Orelhas internas de 178 pacientes com diagnóstico definitivo de doença de Ménière unilateral foram visualizados através de imagem de recuperação de inversão atenuada por fluidos em ressonância magnética tridimensional, 3-D FLAIR, e por inversão real após injeção intratimpânica bilateral de gadolínio. Os exames foram usados para avaliar a presença e o grau de hidropsia endolinfática nos vestíbulos e nas estruturas cocleares, inclusive o giro coclear apical, o giro coclear médio e o giro coclear basal. A correlação da ocorrência de hidropsia endolinfática entre as várias partes da orelha interna foi determinada. Resultados: Hidropsia endolinfática sintomática foi detectada no lado afetado em todos os pacientes, enquanto hidropsia endolinfática assintomática foi detectada no lado contralateral não afetado em 32 pacientes (18,0%). No lado afetado, o giro apical da cóclea e o giro coclear médio demonstraram taxas significativamente mais altas de hidropsia endolinfática do que o giro basal e o vestíbulo. A gravidade da hidropsia endolinfática diminuiu gradualmente do giro apical da cóclea para o giro basal. No lado contralateral, a incidência e o grau da hidropsia endolinfática assintomática detectada foram significantemente maiores nas cócleas do que nos vestíbulos (p < 0,05), sem diferença significante entre os giros cocleares. Conclusões: A progressão da hidropsia endolinfática parece ser direcional, iniciando-se na cóclea. A sua ordem da gravidade diminui gradualmente do giro apical da cóclea para o giro basal e, em seguida, para o vestíbulo. A hidropsia endolinfática no vestíbulo está associada à doença de Ménière sintomática.

Menière's disease and disorders of the carbohydrate metabolism involving the inner ear

Introduction: Menière's disease was described in 1861, but there are still uncertainties regarding its pathophysiology and treatment. Endolymphatic hydrops is recognized as a fundamental pathological characteristic of the disease, as a result of an inadequate absorption of the endolymph. A milder type of endolymphatic hydrops results from an altered chemical composition of the endolymph, due to disorders of the carbohydrate metabolism. Objective: To describe the association of both types of hydrops in patients with Menière disease. Methods: This was a retrospective study of 98 patients with Menière's disease, 62 of whom also presented disorders of the carbohydrate metabolism, and 5 patients with delayed endolymphatic hydrops, 2 of whom also presented disorders of the carbohydrate metabolism. Results: The follow-up of these patients showed that the correction of the metabolic disorders may help in the clinical treatment of Menière's disease and of delayed endolymphatic hydrops, but this does not happen in the more severe types of the diseases. Conclusion: Patients with Menière's disease may present simultaneous disorders of the carbohydratemetabolism, affecting the inner ear. The correction of these disorders helps the clinical treatment but does not preclude the progression of the more severe cases of Menière disease (AU)

The role of magnetic resonance imaging in Ménière disease: the current state of endolymphatic hydrops evaluation / O papel da ressonância magnética na doença de Ménière: a avaliação da hidropsia endolinfática nos dias atuais

ABSTRACT Technical advances in magnetic resonance imaging have allowed to accurately detect and grade endolymphatic space distension in Ménière disease; this was only possible in post-mortem histological studies until a few years ago. Magnetic resonance imaging rules out other causes of vertigo and hearing loss, and is able to evaluate the cochlear and vestibular compartments of the endolymphatic space using a dedicated protocol.

RESUMO Os avanços técnicos na ressonância magnética têm permitido detectar e classificar com acurácia a distensão do espaço endolinfático na doença de Ménière; isso só era possível nos estudos histológicos post-mortem até poucos anos atrás. Além de afastar outras causas de vertigem e de perda auditiva, a ressonância magnética é capaz de avaliar os compartimentos coclear e vestibular do espaço endolinfático por meio de um protocolo dedicado.

Suspensory Tethers and Critical Point Membrane Displacement in Endolymphatic Hydrops

Abstract Introduction Grossly displaced membranes are characteristic of endolymphatic hydrops. The process whereby physiological membrane displacement becomes pathological may be mediated by stress, but the membrane biomechanics underlying this transition are unclear. Objective This study seeks to determine the role of suspensory tethers during pressure-induced membrane displacement in the generation of the membranous lesions seen in this disease entity using a biomechanical model approach. Methods The location of membrane suspensory tethers was identified histologically. The influence of tethers on model membrane configuration during displacement was assessed graphically. The relationship of membrane configuration during displacement to curvature radius was quantified trigonometrically. The relationship of curvature radius to stress susceptibility was determined mathematically. The net effect of suspensory tethers on membrane stress levels for various degrees of membrane distention and displacement was then calculated numerically. Results In the inferior labyrinth, suspensory tethers are found to occur on the membranes' boundaries. Such tethering is found to impose a biphasic effect on membrane curvature with increasing degrees of displacement. As a consequence, tensile stress susceptibility is found to decline with initial membrane displacement to a critical point nadir beyond which stress then increases monotonically. No such effect was found for the superior labyrinth. Conclusion Boundary tethers in the inferior labyrinth are associated with significant tensile stress reductions until a critical point of membrane displacement is reached. Displacements short of the critical pointmay be physiological and even reversible,whereas such displacements beyond the critical point are apt to be overtly hydropic and irreversible.

Recurrent low frequency sensorineural deafness / 临床耳鼻咽喉头颈外科杂志

Low frequency sensorineural deafness is a common subtype of idiopathic sudden deafness. Certain patients suffered recurrent attacks without vertigo, much alike Meniere's disease. Few of them developed into definite Meniere's disease during long-term follow-up in many clinical studies. Although the pathophysiology of recurrent low frequency deafness is yet unknown, the desease is considered associated with early state of endolymphatic hydrops or migraine. Otologists shall be aware of its clinical course and careful explanation is necessary at time of initial informed consent.

Características epidemiológicas y comorbilidades asociadas en pacientes con migraña vestibular definida en Hospital Británico de Buenos Aires: 2014-2016 / Epideniologic characteristics and associated comorbidities in patients with vestibular migraine, Buenos Aires British Hospital: 2014-2016 / Aspectos epidemiológicos e comorbidades em pacientes com enaxaqueca vestibular no Hospital Británico de Buenos Aires:2014 - 2016

Introducción: la migraña vestibular definida es una de las causas más comunes de vértigo, así como el vértigo paroxístico benigno e hidrops endolinfático. Su prevalencia en la población general se ha estimado entre 1,1 a 3,2%. En Latinoamérica son pocos los estudios acerca de las características epidemiológicas y las comorbilidades adjuntas de los pacientes con diagnóstico de migraña vestibular. Este trabajo describe la correlación entre las características epidemiológicas y las comorbilidades adjuntas de los pacientes evaluados por migraña vestibular definida en el Hospital Británico de Buenos Aires en el periodo comprendido entre enero de 2014 y febrero de 2016. Materiales y métodos: Se realizó un estudio observacional descriptivo retrospectivo con revisión manual de historias clínicas de pacientes evaluados en la consulta de otorrinolaringología. Resultados: El estudio mostró que la edad media de los pacientes con migraña vestibular definida fue 44,4 años, observándose mayor número de consultas por pacientes del sexo femenino. Las comorbilidades no otoneurológicas más frecuentes encontradas en el sexo masculino fueron epilepsia y diabetes mellitus tipo II y en el sexo femenino depresión. La comorbilidad otoneurológica más frecuentemente encontrada tanto en el sexo masculino como femenino fue hidrops endolinfático. Conclusiones: En la población las consultas fueron en mayor número de mujeres con una edad media de 44,4 años. Las comorbilidades no otoneurológicas encontradas en hombres fueron epilepsia y diabetes mellitus tipo II y en mujeres depresión. La comorbilidad otoneurológica más encontrada tanto en hombres como en mujeres fue hidrops endolinfático.

Introduction: defined Migraine associated- vertigoisone of the most common etiologies of vertigo as peripheric benign vertigo and endolympatic hydrops are. Its prevalence on population is estimated between 1.1 to 3.2%. In Latin America there are few studies about epidemiologic characteristics and comorbidities of diagnosed patients with defined migraine associated vertigo. This work describes the relationship between the epidemiologic characteristics and the comorbidities of patients evaluated for defined migraine associated vertigo at Buenos Aires British Hospital since january 2014 to february 2016. Methods: An observational, descriptive and retrospective study was done. Clinical records of otolaryngology consult were reviewed. Results: This study showed a mean age of 44.4 years old for the patients of defined migraine associated vertigo, the majority of consults were done for female gender. The most common non – neurotological comorbidities found in male gender were epilepsy and diabetes mellitus type II and in female gender was depression. The most common neurotological condition found in female and male gender was endolympatic hydrops. Conclusions: The majority of consults were achieved by female population with a mean age of 44.4 years old. Non-neurotological comorbidities found in men were epilepsy and diabetes mellitus type II and in women depression. The most common neurotological comorbidity found in men and women was endolymphatic hydrops.

Introdução: a enxaqueca vestibular definitiva é uma das causas mais comuns de vertigem e vertigem paroxística benigna e hidropisia endolinfática. A sua prevalência na população em geral tem sido estimado entre 1,1 e 3,2%. Na América Latina existem poucos estudos sobre a epidemiologia e as co-morbidades que acompanham de pacientes com diagnóstico de enxaqueca vestibular. Este artigo descreve a correlação entre as características epidemiológicas e as co-morbidades que acompanham de pacientes avaliados para a enxaqueca vestibular definidos no Hospital Britânico de Buenos Aires no período compreendido entre Janeiro de 2014 e Fevereiro de 2016. Materiais e métodos: um estudo observacional retrospectivo com revisão manual dos prontuários de pacientes avaliados em consulta de otorrinolaringologia foi realizado. Resultados: O estudo mostrou que a idade média dos pacientes com enxaqueca vestibular definitiva foi de 44,4 anos, mostrando mais consultas por parte de pacientes do sexo feminino. As comorbidades mais freqüentes não otoneurológicas encontrados nos machos foram epilepsia e diabetes mellitus tipo II e depressão em mulheres. A comorbidade otoneurológico mais frequentemente encontrado em ambos os sexos masculino e feminino foi hidropisia endolinfática. Conclusões: na população nas consultas eram mais mulheres com uma idade média de 44,4 anos. Os homens não otoneurológicas comorbidades foram encontrados em epilepsia e diabetes mellitus tipo ii depressão e mulheres. Quanto mais comorbidade otoneurológico encontrados em homens e mulheres era de hidropisia endolinfática.

Recent Research Trend for Ménière's Disease / 대한평형의학회지

Ménière's disease is a poorly understood disorder of the inner ear characterized by intermittent episodic vertigo, fluctuating hearing loss, ear fullness and tinnitus. In this paper, we present a review of the histopathology, cytochemistry, gene, blood-labyrinthine barrier and imaging of Ménière's disease. Histopathology is significant for neuroepithelial damage with hair cell loss, basement membrane thickening, perivascular damage and microvascular damage. Cytochemical alterations are significant for altered AQP4 and AQP6 expression in the supporting cell, and altered cochlin and mitochondrial protein expression. Since the discovery of aquaporin water channels (AQP1, AQP2, AQP3, AQP4, AQP5, AQP6, AQP7 and AQP9), it has become clear that these channels play a crucial role in inner ear fluid homeostasis. Several gene studies related to Ménière's disease have been published, but there is no clear evidence that Ménière's disease is associated with a special gene. Currently, imaging techniques to determine the extent and presence of endolymphatic hydrops are being studied, and further studies are needed to correlate the visualization of the endolymphatic hydrops with clinical symptoms.

Ménière's Disease and Electrophysiology / 대한평형의학회지

Inner ear is composed of cochlea, vestibule, and endolymphatic sac which are enclosed by thin layer of epithelial cells. The enclosed space is filled with fluid named as endolymph where the [K⁺] is high and [Na⁺] is low. This unique ion composition is very important in maintaining normal hearing and balance function by providing K⁺ ions into sensory hair cells, which finally depolarize hair cells to facilitate the transport of sound and acceleration stimulation to central nervous system. The ion composition of inner ear is maintained by various ion transport through ion channels, transporters, and exchangers in the inner ear sensory and extra-sensory epithelium. The disruption of normal endolymphatic ion composition by the deterioration of the function of those ion channels can cause dysfunction of sensory epithelium, which consequently results in hearing and balance disorders. One of the possible pathology from the disruption of inner ear ion homeostasis is endolymphatic hydrops which is a phenomenon of excessive fluid accumulation of inner ear. The dysfunction of ion channels in inner ear epithelium can be an etiology of Ménière's disease since endolymphatic hydrops is a main pathological finding of the disease. In this review, we discussed about the possible pathological mechanism of Ménière's disease as a perspective of channelopathy as well as the role of various ion channels in the regulation of inner ear fluid volume based on the findings revealed by electrophysiological studies.

Usefulness Assessment of Cochlear Hydrops Analysis Masking Procedure Test in Progress of Ménière's Disease / 대한평형의학회지

OBJECTIVE: There were few recent study concern about usefulness of cochlear hydrops analysis masking procedure (CHAMP) in progression of Ménière's disease. The purpose of this study is to analyze changes in the CHAMP as advancement of Ménière's disease. METHODS: We studied 19 cases of ‘ Definite’ group of Ménière's disease. We assumed progression of Ménière's disease would be checked by pure tone threshold by four tone average (4PTA), low tone average (LPTA). We also compared electrocochleography (ECoG), dizziness handicap inventory (DHI), tinnitus handicap inventory (THI) as parameters for progression of Ménière's disease to CHAMP latency delay and amplitude ratio. Chi-square test was used as a statistical method. RESULTS: In the group of patients had abnormal amplitude ratio, ECoG value were not improved, but there was not statistically significant (odds ratio [OR]=5.727, p>0.05). Better DHI and THI score were not necessarily construed as the improvement value in the CHAMP (p>0.05). In amplitude ratio abnormal group, 4PTA was aggravated, but not statistically significant (OR=1.5, p>0.05). In the group of patient had abnormality in both latency delay and amplitude ratio, LPTA was relatively aggravated (OR in latency delay: 2, OR in amplitude ratio: 10); however, reveals no statistically significance between them (p>0.05). Change of ECoG, hearing threshold including 4PTA and LPTA with progression of Ménière's disease were not correlated significantly with latency delay or amplitude ratio of CHAMP. CONCLUSION: We conclude that CHAMP does not reflect clinical features with progression of Ménière's disease.

Why Diagnosis of Meniere's Disease is Difficult? Understanding of the Diagnostic Criteria / 대한이비인후과학회지

The Best clinical approaches for Meniere's disease starts from the proper diagnosis which is based on the clinical symptoms, including the characteristic features of vertigo and auditory symptoms. After first criteria has been made in 1972 by the American Academy of Otolaryngology-Head and Neck Surgery, it has been revised two times in 1985 and 1995. Japanese criteria have been made in 1974 and revised 2008. Most recent criteria of the Barany Society has been established in 2015. The basic notion is almost similar among these criteria, but detailed descriptions has been gradually changed in characteristics of vertigo and auditory symptoms based on the updated research data and consensus. Understanding of how the diagnostic criteria of Meniere's disease has been evolved is very important in terms of good clinical practice because they contain the development of knowledge about the disease. This article reviewed all the diagnostic criteria, and compared the differences.

Is Electrocochleography Still Helpful in Early Diagnosis of Meniere Disease?

BACKGROUND AND OBJECTIVES: Despite the extensive research for the Meniere's disease (MD), it's pathophysiology still remains uncertain and questionable among scientists. Clinical symptoms and audiometric tests form the basis for the diagnosis. Nevertheless the differential diagnosis can be extremely challenging, due to subjective and not specific results. Incorrect diagnosis is most likely and for this reason there is a great demand for objective and reliable tests. SUBJECTS AND METHODS: The presence of endolymphatic hydrops is necessary condition but non enough for the diagnosis. In this study we analyze retrospectively the summating potentials (SP)/action protentials (AP) ratio from peritympanic electrocochleography in 34 patients,divided in two groups (13 patients classified as defined MD and 21 patients classified as probable MD). The purpose was to identify the utility of the exam so to be able to achieve an early defined diagnosis. Furthermore our intention was to obtain an objective test, besides the clinical criteria currently in use for the diagnosis and the classification of the MD. RESULTS: The analysis of the SP/AP results shows high predictability for the MD (positive in six out of seven cases with a sensitivity greater than 80%). CONCLUSIONS: Our study demonstrates a satisfactory sensibility percentage in recurrent defined MD presentation (>80%). Early identification of MD can lead to an early treatment and control of the progression of the disease. Furthermore it could be a valuable instrument for the follow up and evaluation of the patients classified as probable MD in accordance with the criteria of the American Academy of Otolaryngology-Head and Neck Surgery (1995).

A Case of Jugular Foramen Clear Cell Meningioma Presented as Sensorineural Hearing Loss and Recurrent Vertigo / 대한이비인후과학회지

Meningiomas account for 13 to 37% of all primary brain tumors, with 15% of all intracranial meningiomas arising in the posterior fossa. Patients with jugular foramen meningiomas (JFMs) may present with vague, non-specific vertiginous symptoms and sensorineural hearing loss (SNHL). Recently, the author encountered a unique case of JFM with symptoms similar to those of Ménière's disease and those of delayed endolymphatic hydrops. The patient discussed in the present case is a 17-year-old woman with a several month history of right SNHL and recurrent attacks of vertigo. The initial diagnosis of vertigo was later diagnosed as a JFM of the clear cell subtype, which is a remarkably rare pathological finding among intracranial meningioma. This study reports a case of JFM of the clear cell subtype in addition to a review of the literature.

Changes in endolymphatic hydrops visualized by magnetic resonance imaging after sac surgery / 华中科技大学学报（医学）（英德文版）

The purpose of the study was to observe changes in endolymphatic hydrops by using intratympanic injection of gadolinium and magnetic resonance imaging (MRI) before and after endolymphatic sac surgery in patients with unilateral Meniere's disease. Thirteen patients with unilateral Meniere's disease undergoing endolymphatic sac surgery were retrospectively and prospectively analyzed. Three-dimensional fluid-attenuated inversion recovery or three-dimensional real inversion recovery MRI was performed 24 h after an intratympanic injection of gadolinium to grade the presence of endolymphatic hydrops. Among the 13 patients with hydrops confirmed by preoperative MRI, vestibular hydrops had no significant change in all patients; cochlear hydrops became negative in 2 patients, and remained unchanged in the other 11 patients after surgery. Definite vertigo attacks were substantially controlled in one patient and completely controlled in 12 patients during a follow-up period of 8-34 months after surgery. The hearing levels were improved in 3 patients, remained unchanged in 7 patients, and decreased in 3 patients. In conclusion, endolymphatic sac surgery does not always alleviate endolymphatic hydrops in patients with Meniere's disease. Relief from vertigo cannot always be attributed to the remission of hydrops. A change in hearing levels cannot be explained by hydrops status alone.

Experiemental Model for Ménière's Disease Using Surgical Ablation of Endolymphatic Sac / 대한평형의학회지

Endolymphatic hydrops is a representing pathologic finding of Ménière's disease. For the induction of endolymphatic hydrops in an animal model, surgical ablation of endolymphatic sac has been used. Although traditional model with the blockage of endolymphatic sac induced severe hydrops, it has several limitations for the study of pathophysiology of Ménière's disease. Recently, modified experimental models have been introduced, in which additional procedure was performed to induce the acute aggravation of hydrops after the surgical ablation. These new models could be helpful to elucidate the mechanism and develop a new treatment of Ménière's disease. In this review, we introduce the characteristics of animal models using surgical ablation of endolymphatic sac from the classical model to novel modified models.

A History for Experimental Animal Models of Endolymphatic Hydrops / 대한평형의학회지

It is known that endolymphatic hydrops is a pathophysiologic mechanism of Meniere's disease, while the detailed role is not fully clarified. Study for endolymphatic hydrops mainly represents a pathologic histologic finding found only in the post-mortem examination of temporal bone, so endolymphatic hydrops animal models have played important role in terms of understanding how hydrops affects the function of the inner ear. Numerous challenges with diverse animals and techniques have been tried to reveal the possible pathophysiology of endolymphatic hydrops and develop an effective treatment. This review shows historical background and technical advances in experimental animal model for endolymphatic hydrops and Meniere's disease.