Case Report: Ménière's Disease-Like Symptoms in 22q11.2 Deletion Syndrome

The 22q11.2 deletion syndrome (22q11.2DS), caused by a microdeletion on the long arm of chromosome 22, is characterized by congenital heart disease, hypoparathyroidism, immunodeficiency, developmental delay, and velopharyngeal insufficiency. Anatomic malformations of the middle and inner ears are frequently present, leading to high prevalence of hearing impairment. We present a first case of 22q11.2DS showing fluctuating hearing loss with recurrent vertigo attacks, resembling Ménière's disease. A 38-year-old male known to have 22q11.2DS developed recurrent vertigo, tinnitus, and fluctuating hearing loss in the left ear during a 10-year follow-up period. During vertigo attack, he had spontaneous left-beating nystagmus with downbeat components, but bithermal caloric and video head impulse tests showed normal vestibulo-ocular reflex functions. Sequential pure tone audiograms demonstrated fluctuating sensorineural hearing loss (SNHL) in both ears, which finally progressed to permanent hearing loss in the left ear. Computed tomography imaging of the temporal bone exhibited bilaterally malformed lateral semicircular canals, and delayed 3D-FLAIR sequences revealed cochlear endolymphatic hydrops with dilation of the scala media in the left ear. This case shows that acute vertigo with SNHL can be one of the audiovestibular presentations in 22q11.2DS caused by disturbance of endolymphatic flow.

Investigation of endolymphatic hydrops positivity rates in patients with recurrent audiovestibular symptoms using inner ear magnetic resonance imaging

OBJECTIVES

This study aimed to investigate the endolymphatic hydrops (EH)-positivity rates among patients with recurrent audiovestibular symptoms using intravenous injection of gadolinium-enhanced inner ear magnetic resonance imaging (ieMRI).

METHODS

We reviewed 710 successive patients with recurrent audiovestibular symptoms at the Vertigo/Dizziness Center of Nara Medical University and other related hospitals, between May 2014 and April 2020. We performed ieMRI on 153 patients with unilateral recurrent cochleovestibular symptoms (rCV), 51 with recurrent vertigo symptoms (rVO), and 84 with unilateral recurrent cochlear symptoms (rCO).

RESULTS

EH was observed in 69.4% of the participants: 81.7% in the rCV group, 19.6% in the rVO group, and 77.4% in the rCO group. The participants were divided into two groups according to the disease duration: short-duration and long-duration groups. In the short-duration group (less than 4 years), EH was observed in 82.3%, 42.9%, and 71.4% of the patients in rCV, rVO, and rCO groups, respectively; in the long-duration group (more than 5 years), EH was observed in 81.1%, 10.8%, and 81.6% of the patients in rCV, rVO, and rCO groups, respectively.

CONCLUSIONS

The longer the duration of the disease, the larger the EH-positivity rates in patients with rCO, smaller in those with rVO, and unchanged in those with rCV. Although ieMRI could not detect EH with 100% accuracy in Ménière's disease, the present pathological statistics of patients with recurrent audiovestibular symptoms might be helpful in considering the pathology-based treatment strategy.

Endolymphatic Hydrops in Fluctuating Hearing Loss and Recurrent Vertigo

Background: Endolymphatic hydrops (EH) is the histopathological hallmark of Ménière's disease (MD) and has been found by in vivo magnetic resonance imaging (MRI) in patients with several inner ear syndromes without definite MD criteria. The incidence and relevance of this finding is under debate.

Purpose: The purpose of the study is to evaluate the prevalence and characteristics of EH and audiovestibular test results in groups of patients with fluctuating audiovestibular symptoms not fulfilling the actual criteria for definite MD and compare them with a similar group of patients with definite MD and a group of patients with recent idiopathic sudden neurosensory hearing loss (ISSNHL).

Material and Methods: 170 patients were included, 83 with definite MD, 38 with fluctuating sensorineural hearing loss, 34 with recurrent vertigo, and 15 with ISSNHL. The clinical variables, audiovestibular tests, and EH were evaluated and compared. Logistic proportional hazard models were used to obtain the odds ratio for hydrops development, including a multivariable adjusted model for potential confounders.

Results: No statistical differences between groups were found regarding disease duration, episodes, Tumarkin spells, migraine, vascular risk factors, or vestibular tests; only hearing loss showed differences. Regarding EH, we found significant differences between groups, with odds ratio (OR) for EH presence in definite MD group vs. all other patients of 11.43 (4.5–29.02; p < 0.001). If the ISSNHL group was used as reference, OR was 55.2 (11.9–253.9; p < 0.001) for the definite MD group, 9.9 (2.1–38.9; p = 0.003) for the recurrent vertigo group, and 5.1 (1.2–21.7; p = 0.03) for the group with fluctuating sensorineural hearing loss.

Conclusion: The percentage of patients with EH varies between groups. It is minimal in the ISSNHL group and increases in groups with increasing fluctuating audiovestibular symptoms, with a rate of severe EH similar to the known rate of progression to definite MD in those groups, suggesting that presence of EH by MRI could be related to the risk of progression to definite MD. Thus, EH imaging in these patients is recommended.

MRI With Gadolinium as a Measure of Blood-Labyrinth Barrier Integrity in Patients With Inner Ear Symptoms: A Scoping Review

Objective: Capillaries within the inner ear form a semi-permeable barrier called the blood-labyrinth barrier that is less permeable than capillary barriers elsewhere within the human body. Dysfunction of the blood-labyrinth barrier has been proposed as a mechanism for several audio-vestibular disorders. There has been interest in using magnetic resonance imaging (MRI) with intravenous gadolinium-based contrast agents (GBCA) as a marker for the integrity of the blood labyrinth barrier in research and clinical settings. This scoping review evaluates the evidence for using intravenous gadolinium-enhanced MRI to assess the permeability of the blood-labyrinth barrier in healthy and diseased ears.

Methods: A systematic search was conducted of three databases: PubMed, EMBASE, CINAHL PLUS. Studies were included that used GBCA to study the inner ear and permeability of the blood-labyrinth barrier. Data was collected on MRI protocols used and inner ear enhancement patterns of healthy and diseased ears in both human and animal studies.

Results: The search yielded 14 studies in animals and 53 studies in humans. In healthy animal and human inner ears, contrast-enhanced MRI demonstrated gradual increase in inner ear signal intensity over time that was limited to the perilymph. Signal intensity peaked at 100 min in rodents and 4 h in humans. Compared to controls, patients with idiopathic sudden sensorineural hearing loss and otosclerosis had increased signal intensity both before and shortly after GBCA injection. In patients with Ménière's disease and vestibular schwannoma, studies reported increased signal at 4 h, compared to controls. Quality assessment of included studies determined that all the studies lacked sample size justification and many lacked adequate control groups or blinded assessors of MRI.

Conclusions: The included studies provided convincing evidence that gadolinium crosses the blood-labyrinth barrier in healthy ears and more rapidly in some diseased ears. The timing of increased signal differs by disease. There was a lack of evidence that these findings indicate general permeability of the blood-labyrinth barrier. Future studies with consistent and rigorous methods are needed to investigate the relationship between gadolinium uptake and assessments of inner ear function and to better determine whether signal enhancement indicates permeability for molecules other than gadolinium.

The relationship between nutrition and Ménière's disease

Ménière's disease is an inner ear disease with attacks characterized by ear fullness, tinnitus, fluctuant sensorineural hearing loss and vertigo. Although pathophysiology of the disease is not fully known, endolymphatic hydrops are believed to play a role. Although there is no certain treatment procedure for Ménière's disease, some treatments are applied to prevent attacks, to treat the symptoms that occur during the attacks, and to prevent the permanent effects of the symptoms on the hearing and balance system. Lifestyle changes, dietary modifications, diuretics, vasodilator corticosteroids, intratympanic steroids, surgical methods are some of these treatment methods. Dietary modification includes a low sodium diet, a reduction in daily alcohol and caffeine intake, a gluten-free diet, and a new dietary approach to specially processed grains, all of which are first-line treatments. The goal of this review article is to examine the relationship between MD and dietary intervention, which is frequently used in the prevention and treatment of MD attacks.

Case Report: Positive Pressure Therapy Combined With Endolymphatic sac Surgery in a Patient With Ménière's Disease

Positive pressure therapy (PPT) is applied for medically-intractable vertigo in Ménière's disease (MD); however, it remains unknown whether PPT affects in vivo endolymphatic hydrops (EH). In this case report, we describe a 5-year course of MD in a patient in which EH was repeatedly observed. As the patient experienced recurrent vertigo attacks after endolymphatic sac surgery, he began to use the PPT device additionally and vertiginous episodes decreased in accordance with a decrease in the EH volume. The mechanism of PPT is suggested that the pressure increase in the middle ear inhibits EH development. PPT, if added after surgery, might be more effective to reduce EH volume compared with surgery alone. A larger study group size is required to test these preliminary data concerning EH changes.

Dynamics in Endolymphatic Hydrops & Symptoms in Meniere's Disease After Endolymphatic Duct Blockage, Preliminary Results

Objective: The purpose of the present study was to evaluate the dynamics of endolymphatic hydrops (EH) and symptoms in a group of patients who underwent endolymphatic duct blockage (EDB) for treatment of intractable Meniere's Disease (MD), and to explore a metric for verifying the effectiveness of EDB procedure.

Methods: A total of 22 patients with intractable MD patients who underwent EDB participated in the present study. EH was visualized using locally enhanced inner ear magnetic resonance imaging (MRI) prior to and following surgery. The vestibular hydrops ratio (VHR) in the second MRI examination was compared with the pre-surgery recordings.

Results: Following EDB, 6 patients exhibited complete or partial reversal of EH, complete control of vertigo spells and reported improvement in hearing; 13 patients showed no changes in EH or hearing, but 5 of these patients exhibited complete control of vertigo attacks, and the other 8 patients exhibited improved control of vertigo attacks. The final 3 patients showed an increase in EH, but symptomatic worsening in 2 patients, and symptomatic improvement in 1 patient. There was a significant difference in the average VHR prior to and following EDB. Postoperative VHR was positively correlated with the frequency of vertigo spells in the latest 6 months of follow-up and improvement of postoperative average hearing threshold.

Conclusion: The decreased EH accompanying the reduction in vertigo attacks and hearing preservation may provide a metric for verifying the effectiveness of EDB treatment in patients with MD.

The Correlation of a 2D Volume-Referencing Endolymphatic-Hydrops Grading System With Extra-Tympanic Electrocochleography in Patients With Definite Ménière's Disease

Background: Although magnetic resonance imaging (MRI) of the membranous labyrinth and electrocochleography (ECochG) have been used to diagnose endolymphatic hydrops (ELH) in patients with Ménière's disease (MD), the relationship between imaging and ECochG is not well-documented. Objectives: This study evaluates the ELH using 3D-FLAIR MRI and extra-tympanic ECochG (ET-ECochG) and correlates the results from 3D-FLAIR MRI to those from ET-ECochG. Materials and Methods: 3D-FLAIR MRI images of 50 patients were assessed using a 2D volume-referencing grading system (VR scores, relative scores according to the known volumes of the cochlea, vestibule, and semicircular canals). Forty healthy subjects were included and compared to 51 definite MD ears of 50 patients while analyzing the ET-ECochG, which used a self-made bronze foil electrode. The amplitude ratio of the summating potential (SP) to the action potential (AP) (SP/AP) and the area ratio of SP to AP (Asp/Aap) were collected. Relative ELH grade scores were then correlated to ET-ECochG (SP/AP, Asp/Aap). Results: The VR scores showed a better correlation (r = 0.88) with the pure tone average (PTA), disease duration, and vertigo frequency of MD than the Bernaerts scores (grading the cochlea and vestibule separately) (r = 0.22). The SP/AP and Asp/Aap of the unilateral MD patients were statistically comparable to those measured in contralateral ears and the results between the definite MD ears with healthy ears were statistically comparable (p < 0.05). In a ROC analysis Asp/Aap (area under curve, AUC 0.98) significantly (p = 0.01) outperformed SP/AP (AUC 0.91). The total score of ELH, vestibular ELH, and cochlear ELH were also correlated with SP/AP and Asp/Aap. The strongest correlation was found between the Asp/Aap and cochlear ELH (r = 0.60). Conclusion: The 2D volume-referencing grading system was more meaningful than the Bernaerts scores. A correlation was found between ELH revealed by 3D-FLAIR MRI and the SP/AP of ET-ECochG in evaluating definite MD patients. The Asp/Aap appeared a more sensitive and reliable parameter than SP/AP for diagnosing the ELH of the membranous labyrinth.

Magnetic resonance imaging of the inner ear in the diagnostics of Ménière's disease

Ménière's disease is characterized by sudden episodes of vertigo accompanied by tinnitus and/or feeling of fullness in the ear as well as fluctuating sensorineural hearing loss. Despite numerous studies, the etiology of this disease remains unknown. However, the enlargement of the inner ear's endolymphatic spaces, referred to as endolymphatic hydrops, is considered the underlying condition. Thanks to recent advances in magnetic resonance (MR) technology, it is now possible to obtain in vivo imaging of endolymphatic hydrops in patients presenting with Ménière's disease symptoms. Visualization of the inner ear fluid compartments is achieved after gadolinium contrast is administered into the tympanic cavity or via the intravenous route. Evaluation of endolymphatic hydrops is possible as the contrast agent selectively penetrates the perilymph, and endolymph is visualized as contrast defects. The currently used radiological hydrops grading systems include qualitative, semi-quantitative, and volumetric scales. The methods are subject to ongoing modifications to increase their sensitivity and specificity. Numerous studies describe correlations between clinical symptoms and audiological and otoneurological examination results with the endolymphatic hydrops grade. MRI is also applicable in patients' diagnostics with an incomplete or atypical course of the Ménière's disease. In the course of the treatment, follow-up MRI scans enable assessing individual treatment modalities' efficacy in terms of the severity of lesions and the further course of the disease within the inner ear.

Occlusion of the Lateral Semicircular Canal Through the External Ear Canal: A Case Report

This case report introduces a novel surgical procedure to occlude the lateral semicircular canal through the external auditory canal. The patient was a 64-year-old male with Ménière's disease who had suffered from left ear vertigo accompanied by tinnitus for more than 4 years. He also suffered from paroxysmal vertigo, fluctuating hearing loss, tinnitus symptoms, and ear distension and tightness. The patient had been treated with dexamethasone injected into the tympanic cavity for 1 year, but his condition often recurred and could not be controlled. We developed a novel procedure using an endoscope to occlude the lateral semicircular canal through the external auditory canal to provide a surgical option for the treatment of Ménière's disease.

Platform posturography of patients with peripheral vestibular dysfunction in the non-acute phase of vertigo

OBJECTIVE

Posturography (PG) shows various patterns corresponding to a patient's equilibrium condition; however, PG is not useful for the differential diagnosis of peripheral vestibular diseases (PVDs). The aim of this study was to identify parameters of PG that can distinguish between PVDs.

METHODS

The differences in PG parameters between PVDs were evaluated retrospectively. Two hundred and two patients with Ménière's disease (MD), 154 patients with benign paroxysmal positional vertigo (BPPV), 20 patients with sudden sensorineural hearing loss with vertigo (SSNHLwV), and 31 patients with vestibular neuritis (VN) underwent PG during the non-acute phase of vertigo, from January 2010 to March 2017.

RESULTS

The velocity of body oscillation of BPPV patients with eyes open and closed were significantly faster than those of MD patients with eyes open (p < 0.001) and closed (p = 0.033). The velocity of body oscillation of VN patients with eyes open was significantly faster than that of MD patients with eyes open (p = 0.0083). There were no significant differences among the other PG parameters between PVDs. Although there were significant differences among the velocity with eyes open and closed between males and females (eye open: p = 0.0009, eye close: p < 0.0001), there was no significant difference in the ratio of males to females among PVDs (p = 0.1834). Therefore, the ratio did not influence the difference in velocity among PVDs. Patient age correlated with the velocity with eyes open (p < 0.001) and with eyes closed (p < 0.001). Post-hoc analysis revealed significant differences in patient age, and comparisons of MD and BPPV, MD and SSNHLwV, BPPV and VN, and VN and SSNHLwV. Therefore, we performed multiple regression analysis to determine whether the significant differences in the velocity of body oscillation among PVDs were caused by the difference in age distribution between PVD groups, rather than by differences in the PVDs themselves. There were correlations between age and the velocity of body oscillation with eyes open (p < 0.001) and with eyes closed (p < 0.001). There also were correlations between MD or VN and the velocity of body oscillation with eyes open (p = 0.0194).

CONCLUSION

There were significant differences in the velocity of body oscillation with eyes open between MD and VN patients. The difference between MD and VN was significant regardless of the age distribution. To distinguish between MD and VN, the velocity of body oscillation with eyes open is a useful PG index.

Is cochlear synapse loss an origin of low-frequency hearing loss associated with endolymphatic hydrops?

There is a strong association between endolymphatic hydrops and low-frequency hearing loss, but the origin of the hearing loss remains unknown. A reduction in the number of cochlear afferent synapses between inner hair cells and auditory nerve fibres may be the origin of the low-frequency hearing loss, but this hypothesis has not been directly tested in humans or animals. In humans, measurements of hearing loss and postmortem temporal-bone based measurements of endolymphatic hydrops are generally separated by large amounts of time. In animals, there has not been a good objective, physiologic, and minimally invasive measurement of low-frequency hearing. We overcame this obstacle with the combined use of a reliable surgical approach to ablate the endolymphatic sac in guinea pigs and create endolymphatic hydrops, the Auditory Nerve Overlapped Waveform to measure low-frequency hearing loss (≤ 1 kHz), and immunohistofluorescence-based confocal microscopy to count cochlear synapses. Results showed low- and mid-(1-4 kHz) frequency hearing loss at all postoperative days, 1, 4, and 30. There was no statistically significant loss of cochlear synapses, and there was no correlation between synapse loss and hearing function. We conclude that cochlear afferent synaptic loss is not the origin of the low-frequency hearing loss in the early days following endolymphatic sac ablation. Understanding what is, and is not, the origin of a hearing loss can help guide preventative and therapeutic development.

Personality and psychopathology in Ménière's disease

INTRODUCTION AND OBJECTIVES

Psychological factors in vertigo patients have been extensively studied but the role of anxiety and personality traits in the clinical course of Ménière's disease (MD) is unknown. The objectives of this study are to identify and characterize psychopathology in MD and to find risk factors for an increased rate and intensity of crisis and chronic symptoms.

MATERIALS AND METHODS

We performed a transversal study in all patients diagnosed with definite MD in our department during a 5-year period. Sample subjects were interviewed in 3 steps: first, an otorhinolaryngologist collected information about clinical and pharmacological background of MD; second, a psychiatrist screened for mood, anxiety and personality disorders; in a third stage, the patient completed the DHI (Dizziness Handicap Inventory), STAI-Y (State Trait Anxiety Inventory), NEO-PI-R (Neo Personality Inventory Reviewed) and VAS (Visual Analogue Scale) for vertigo and dizziness. Statistical analysis was performed to search for risk factors for multiple and intense crisis and chronic symptoms.

RESULTS

Thirty-four patients completed all 3 phases of the study. A predominant dysfunctional personality trait was identified in 80% of patients (predominantly cluster C type), 35% were being treated with psychiatric medication and 34.4% had a considerable mood or anxiety disorder. All patients scored high (>7) in VAS during crisis. There was a statistically significant positive correlation between crisis rate and STAI, anxiety-subscale (N1) in NEO-PI-R, VAS and DHI scores (p<.044). Crises were more common in bilateral MD (p=.041). DHI scores were higher with higher STAI and N1 (p=.001). Disease duration and pure tone average were found to have a positive moderate correlation (p=.017).

CONCLUSIONS

The positive correlations between crisis rate, chronic dizziness and anxiety-related personality traits reveal a bidirectional and intimate relationship between personality, anxiety and MD, affecting these patients' quality of life. These results support the relevance of prospecting adjuvant psychological and psychiatric approaches to these patients.

Bidirectional analysis of the association between Ménière's disease and depression: Two longitudinal follow-up studies using a national sample cohort

OBJECTIVE

This study aimed to delineate the causal relationship between Ménière's disease and depression.

DESIGN

Two longitudinal follow-up studies.

MAIN OUTCOME MEASURES

The 2002-2013 Korean National Health Insurance Service-Health Screening Cohort was used. In study I, Ménière's disease patients were 1:4 matched with the control I group for age group, sex, income group and region of residence, and the occurrence of depression was observed. In study II, the depression patients were 1:4 matched with the control II group for the same variables, and the occurrence of Ménière's disease was observed. The stratified Cox proportional hazard model was used. Subgroup analyses were performed according to age and sex.

RESULTS

In study I, 6.9% (420/6044) of the Ménière's disease patients and 3.7% (885/24 176) of the control I participants experienced depression. The adjusted hazard ratio (HR) of Ménière's disease for depression was 1.94 (95% confidence intervals [CI] = 1.73-2.18, P < .001). In study II, 1.6% (490/31 649) of the depression patients and 1.0% (1240/126 596) of the control II participants were diagnosed with Ménière's disease. The adjusted HR of depression for Ménière's disease was 1.58 (95% CI = 1.43-1.76, P < .001). All age and sex subgroups demonstrated higher HRs of Ménière's disease for depression (study I) and depression for Ménière's disease (study II).

CONCLUSION

Ménière's disease patients showed an increased likelihood of depression. Conversely, depression patients showed an elevated likelihood of Ménière's disease.

[A review of endolymphatic sac-related surgeries and their possible mechanisms]

Endolymphatic sac-related surgeries are a series of effective procedures to treat patients with Ménière's disease. However, there is controversy since they were proposed in 1927. Although most studies have shown the effectiveness of endolymphatic decompression and endolymphatic shunting, the mechanisms of them are still unclear. Some studies suggested that these procedures work because the endolymphatic hydrops relieves after surgery. However, the new one proposed recently, endolymphatic duct blockage, seems to contradict to the relief theory. Therefore, this article reviewed the mechanisms of endolymphatic hydrops and the development of a series of sac surgeries to better understand the possible mechanisms of sac surgeries.

Usefulness of Ultrasound-Computer-Craniocorpography in Unilateral Ménière's Disease

Background

Ménière's disease (MD) is composed of a set of fluctuating symptoms, whereby vertigo is the most unpleasant among them and often accompanied by deterioration of the balance system.

Objectives

The purpose of this study is to objectively assess the Romberg and Unterberger-Fukuda tests by ultrasound-computer-craniocorpography (US-COMP-CCG) in patients suffering from MD and to characterize the balance disorders in different frames of MD.

Methods

This is a case-control study where 51 patients with normal vestibular system and 42 patients suffering from definite MD were examined by US-COMP-CCG. They were divided into three grades according to the attack rates and the complaints of the patient during the attack-free periods.

Results

Parameters of significance showing the worsening of the balance system with the aggravation of the disease are seen in both tests. In the standing test, the longitudinal and lateral sway and the forehead covering values are of importance, whereas in the stepping test, the parameter of relevance is the lateral sway.

Conclusions

The severity of worsening of the balance system, based on the objective results of the system parameters, are parallel to the worsening of MD based on our findings.

Vestibular Neurectomy for Intractable Vertigo: Case Series and Evaluation of Role of Endoscopic Assistance in Retrolabyrinthine Craniotomy

Objective  This study evaluates the utility of endoscopy for retrolabyrinthine vestibular nerve section (RLVNS). Design/Setting  This is a retrospective review for RLVNSs by the senior author. The endoscope's utility was assessed and assigned a grade based on operative findings. Participants/Main Outcome Measures  Fifteen patients (eight males and seven females; 53 and 47%, respectively) were identified with mean age 56.7 years. Indications included Ménière's disease (MD) in 12 of 15 patients (80%), uncompensated vestibular neuritis in 2 patients (13%), and other vestibular neuropathy in 1 patient (7%). Vertigo resolved in 14 of 15 patients (93%). Complications included decreased hearing in two patients (13%) and deep venous thrombosis in one patient (7%). There were no facial nerve complications or mortalities. Results  Sectioning vestibular division of the vestibular-cochlear nerve was achieved without perceived benefit of endoscopy in the 80% of cases (grade 0, n  = 12). Endoscopy was helpful in patients with a small mastoid (grade 1, n  = 2, 13.3%), and deemed necessary where the flocculus of the cerebellum was adherent to the eighth nerve arachnoid at the porus acusticus (grade 2, n  = 1, 6.7%). Conclusion  RLVNS is a safe and efficacious procedure for the treatment of vertigo; the surgical endoscope may be a useful adjunct in selected cases. Patients with MD may expect the greatest benefit from surgery.

Whole-exome sequencing suggests multiallelic inheritance for childhood-onset Ménière's disease

The genetic background of Ménière's disease (MD) was studied in one patient with childhood-onset MD and his grandfather affected with middle age-onset MD. Whole-exome sequencing was performed and the data were compared to 76 exomes from unrelated subjects without MD. Thirteen rare inner ear expressed variants with pathogenic estimations were observed in the case of childhood-onset MD. These variants were in genes involved in the formation of cell membranes or the cytoskeleton and in genes participating in cell death or gene-regulation pathways. His grandfather shared two of the variants: p.Y273N in HMX2 and p.L229F in TMEM55B. HMX2 p.Y273N was considered the more likely candidate for MD, as the gene is known to affect both hearing and vestibular function. The variant in the HMX2 gene may affect inner ear development and structural integrity and thus might predispose to the onset of MD. As there was a significant difference in onset between the patients, an accumulation of defects in several pathways is probably responsible for the exceptionally early onset of the disease, and the genetic etiology of childhood-onset MD is most likely multifactorial. This is the first molecular genetic study of childhood-onset MD.

Auditory brainstem response

The auditory brainstem response (ABR), consisting of five to six vertex-positive peaks with separation of about 0.8ms, is very sensitive to factors that affect conduction velocity and hence ABR wave latencies in the brainstem auditory pathways. In addition, disorders causing dissynchronization of neural activity result in an amplitude decrease or disappearance of ABR peaks. The opposite effects occur in the maturation process, which takes about 2 years postterm; here conduction velocity increases quickly to its adult value, but synaptic delays being sensitive to synchronous release of transmitter substance take considerably longer. In neurological disorders, those that cause dissynchrony, such as auditory neuropathy and vestibular schwannoma, Gaucher disease, and Krabbe disease, the (longer latency) ABR peaks are reduced or absent. Effects on neural conduction, resulting in increased ABR interwave latencies, are found in vestibular schwannomas, Bell's palsy, Duane retraction syndrome, Marcus Gunn ptosis, and various encephalomyopathies. These measures allow an assessment of the parts of the brainstem that are involved.

Cochlea and auditory nerve

The transduction process in the cochlea requires patent hair cells. Population responses that reflect this patency are the cochlear microphonic (CM) and summating potential (SP). They can be measured using electrocochleography (ECochG). The CM reflects the sound waveform in the form of outer hair cell (OHC) depolarization and hyperpolarization, and the SP reflects the average voltage difference of the OHC membrane potential for depolarization and hyperpolarization. The CM can be measured using ECochG or via the so-called otoacoustic emissions, using a sensitive microphone in the ear canal. Neural population responses are called the compound action potentials (CAPs), which by frequency selective masking can be decomposed into narrow-band action potentials (NAPs) reflecting CAPs evoked by activity from small cochlear regions. Presence of CM and absence of CAPs are the diagnostic hallmarks of auditory neuropathy. Increased and prolonged SPs are often found in Ménière's disease but are too often in the normal range to be diagnostic. When including NAP waveforms, Ménière's disease can be differentiated from vestibular schwannomas, which often feature overlapping symptoms such as dizziness, hearing loss, and tinnitus. The patency of the efferent system, particularly the olivocochlear bundle, can be tested using the suppressive effect of contralateral stimulation on the otoacoustic emission amplitude.

Simultaneous Presentation of Definite Vestibular Migraine and Definite Ménière's Disease: Overlapping Syndrome of Two Diseases

Objectives: To review the clinical records of patients that exhibited the clinical features of both vestibular migraine (VM) and Ménière's disease (MD) during each episodic vertigo attack and to discuss the possible pathophysiology of such combination of symptoms.

Subjects: Ten patients that were selected according to criteria based on a combination of the diagnostic criteria for definite MD and VM (9 females and one male, age: 22–54 years) were enrolled. They were required to show features of both diseases in each vertigo attack.

Methods: The patients' medical histories and pure-tone audiometry, cervical vestibular evoked myogenic potential (cVEMP), video head-impulse test (vHIT), and caloric test results were examined. cVEMP was recorded using 500 and 1,000 Hz short tone bursts (125dBSPL, air-conducted), 500 Hz-1,000 Hz cVEMP slope, an index of endolymphatic hydrops in the saccule was calculated using normalized amplitudes of p13-n23. For performing vHIT, each subject was seated 1.5 m in front of a target and asked to keep watching it as their head was passively rotated by the examiner. Their eye movements were evaluated using video-oculography while their head movements were recorded using inertial sensors.

Results: The patients were predominantly female. On average, the onset of migrainous headaches occurred 9 years earlier than the onset of vertigo attacks. All of the patients but one had migraines with auras. Five of the 10 patients had a family history of vertigo attacks accompanied by both migrainous and auditory symptoms. The patients mainly displayed hearing loss at low frequencies. Nine patients exhibited 500–1,000 Hz cVEMP slope < −19.9, which was suggestive of endolymphatic hydrops. None of the patients who underwent vHIT showed abnormal canal function. One patient showed unilaterally decreased caloric responses.

Conclusions: These patients presented with simultaneous MD and VM signs/symptoms might be referred to “VM/MD overlapping syndrome (VM/MD-OS)” as a new clinical syndrome.

[The peculiar features of the clinical course of Meniere's disease associated with benign paroxysmal positional vertigo]

AIM

The objective of the present study was to evaluate the frequency of occurrence and clinical features of vertigo spells in the patients presenting with Ménière's disease (MD) associated with benign paroxysmal positional vertigo (BPPV).

METHODS

A total of 104 patients with MD were available for the observation. All of them underwent the comprehensive examination that included the audiological study and vestibular tests, such as the Dix-Hallpike test and the roll-test for BPPV diagnostics. A structured questionnaire was used to calculate the average number of vertigo spells per month during the period of 6 months and the mean duration of the vertigo spells; the presence or the absence of changes in hearing ability during the spells as well as the severity of vertigo were determined with the use of the 10-point visual analogue scale.

RESULTS

The patients suffering from BPPV associated with Meniere's disease presented with the following clinical features which distinguished them from the patients with idiopathic BPPV (p<0.05): (1) a higher percentage of female patients; (2) a longer duration of clinical symptoms; (3) the frequent involvement of the horizontal semicircular canal; (4) a greater incidence of canal paresis; (5) more therapeutic sessions needed for the recovery in conjunction with a higher rate of recurrence.

CONCLUSION

The frequency of association of MD and BPPV was estimated at 14.4%. Such association of MD was more frequently observed in the elderly patients (older than 60 years) (p<0.05). The clinical manifestations of the vertigo spells in the patients having MD associated with BPPV occurred with an enhanced frequency; their mean duration was relatively short due to the presence of both long and short positional vertigo attacks characterized by the absence of hearing changes during the spells and the equal severity of vertigo (p < 0,05).

International consensus (ICON) on treatment of Ménière's disease

OBJECTIVE

To present the international consensus for recommendations for Ménière's disease (MD) treatment.

METHODS

Based on a literature review and report of 4 experts from 4 continents, the recommendations have been presented during the 21st IFOS congress in Paris, in June 2017 and are presented in this work.

RESULTS

The recommendation is to change the lifestyle, to use the vestibular rehabilitation in the intercritic period and to propose psychotherapy. As a conservative medical treatment of first line, the authors recommend to use diuretics and Betahistine or local pressure therapy. When medical treatment fails, the recommendation is to use a second line treatment, which consists in the intratympanic injection of steroids. Then as a third line treatment, depending on the hearing function, could be either the endolymphatic sac surgery (when hearing is worth being preserved) or the intratympanic injection of gentamicin (with higher risks of hearing loss). The very last option is the destructive surgical treatment labyrinthectomy, associated or not to cochlear implantation or vestibular nerve section (when hearing is worth being preserved), which is the most frequent option.

Disorders of the inner-ear balance organs and their pathways

Disorders of the inner-ear balance organs can be grouped by their manner of presentation into acute, episodic, or chronic vestibular syndromes. A sudden unilateral vestibular injury produces severe vertigo, nausea, and imbalance lasting days, known as the acute vestibular syndrome (AVS). A bedside head impulse and oculomotor examination helps separate vestibular neuritis, the more common and innocuous cause of AVS, from stroke. Benign positional vertigo, a common cause of episodic positional vertigo, occurs when otoconia overlying the otolith membrane falls into the semicircular canals, producing brief spells of spinning vertigo triggered by head movement. Benign positional vertigo is diagnosed by a positional test, which triggers paroxysmal positional nystagmus in the plane of the affected semicircular canal. Episodic spontaneous vertigo caused by vestibular migraine and Ménière's disease can sometimes prove hard to separate. Typically, Ménière's disease is associated with spinning vertigo lasting hours, aural fullness, tinnitus, and fluctuating hearing loss while VM can produce spinning, rocking, or tilting sensations and light-headedness lasting minutes to days, sometimes but not always associated with migraine headaches or photophobia. Injury to both vestibular end-organs results in ataxia and oscillopsia rather than vertigo. Head impulse testing, dynamic visual acuity, and matted Romberg tests are abnormal while conventional neurologic assessments are normal. A defect in the bony roof overlying the superior semicircular canal produces vertigo and oscillopsia provoked by loud sound and pressure (when coughing or sneezing). Three-dimensional temporal bone computed tomography scan and vestibular evoked myogenic potential testing help confirm the diagnosis of superior canal dehiscence. Collectively, these clinical syndromes account for a large proportion of dizzy and unbalanced patients.

RNA-sequencing study of peripheral blood mononuclear cells in sporadic Ménière's disease patients: possible contribution of immunologic dysfunction to the development of this disorder

To date, the pathogenesis of Ménière's disease (MD) remains unclear. This study aims to investigate the possible relationship between potential immune system-related genes and sporadic MD. The whole RNA-sequencing (RNA-seq) technology was used to analyse the transcriptome of peripheral blood mononuclear cells of three MD patients and three control individuals. Of 366 differentially expressed genes (DEGs), 154 genes were up-regulated and 212 genes were down-regulated (|log₂ fold change| > 1 and P < 0·05). Gene ontology (GO) enrichment analysis illustrated that immune relevant factors played a key role in the pathogenesis of MD. Of 366 DEGs, we focused upon analysing the possible immune-related genes, among which the significantly up-regulated genes [glutathione S-transferase mu 1 (GSTM1), transmembrane protein 176 (TMEM176)B, TMEM176A] and down-regulated genes [solute carrier family 4 member (SLC4A)10 and SLC4A1] especially drew our attention. The mRNA expression levels of GSTM1, TMEM176B, TMEM176A, SLC4A1 and SLC4A10 were analysed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The serum concentration of GSTM1, TMEM176B and SLC4A10 proteins were measured by enzyme-linked immunosorbent assay (ELISA). Considering the results of qRT-PCR and ELISA, it was noteworthy that GSTM1 exhibited the highest fold change between two groups, which was consistent with the deep sequencing results by RNA-seq. In conclusion, our study first offers a new perspective in MD development on the basis of RNA expression patterns, suggesting that immune factors might be involved in the MD pathogenesis. Remarkably, GSTM1 might be a possible candidate gene for the diagnostic biomarker of MD and provides the basis for further biological and functional investigations.