What is Menière's disease? A contemporary re-evaluation of endolymphatic hydrops

Association of Metabolic Dysfunction-Associated Steatotic Liver Disease With Sudden Sensorineural Hearing Loss Among Older Adults

Objectives

This study examined the association between metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of sudden sensorineural hearing loss (SSNHL) in elderly individuals.

Methods

A population-based cohort study using the Korean National Health Insurance Service-Senior cohort included 189,623 individuals aged 65 and older, categorized as non-SLD or MASLD. Cox proportional hazards regression and Fine-Gray subdistribution hazard models were used to evaluate the risk of SSNHL and Ménière's disease, considering all-cause mortality as a competing event.

Results

Baseline characteristics showed that MASLD participants had higher metabolic dysfunction markers, including elevated body mass index, waist circumference, and blood pressure, compared to the non-SLD group. During 9 years of follow-up, 3803 SSNHL events occurred in the MASLD group, with an incidence rate of 2.44 per 1000 person-years. After inverse probability of treatment weighting, MASLD was associated with a significantly increased risk of SSNHL (adjusted hazard ratio: 1.05, 95% CI: 1.00-1.10; p = 0.039; subdistribution hazard ratio: 1.06, 95% CI: 1.01-1.11; p = 0.016).

Conclusion

MASLD is associated with an increased risk of SSNHL. This study provides evidence supporting a metabolic influence on auditory health, warranting further investigation into the liver-ear axis.

Level of Evidence

Step 3 (Level 3*)-Cohort study.

Emerging trends in biosensor and microfluidics integration for inner ear theragnostics

Advancements in inner ear theragnostics are critical for addressing the pervasive challenges of diagnosing and treating hearing and balance disorders, which significantly impact quality of life. This paper reviews biosensors and devices that leverage advanced functional nanomaterials, microfabrication techniques, and nano-biotechnology to enhance theragnostic applications for the inner ear. The paper highlights the development of diverse electromechanical, electrochemical, and biomarker sensors for inner ear theragnostics. Electromechanical sensors replicate the cochlear and vestibular sensory structures through bioinspired designs, while electrochemical sensors are used to measure the level of ions and chemicals in the inner ear fluid, providing insights into the health and disease of the hearing and balance organs. Biomarker sensors focus on screening of inner ear diseases through early detection of correlated biomarkers based on point of care diagnostics. This study also examines the use of microfluidic devices with sensory elements to provide a compact and integrated model of the fluid-filled cochlea. In addition, advanced delivery strategies, including targeted drug delivery systems and nanocarriers are explored for their ability to improve the penetration and distribution of therapeutics within the inner ear. The study also highlights the importance of pharmacokinetics and post-treatment monitoring as critical indicators for assessing the efficacy of micro/nanotechnology-based theragnostic approaches. By consolidating these innovations, this work offers a comprehensive framework for advancing otology, paving the way for novel diagnostic tools, effective treatments, and future clinical applications.

Distinctive clinical features of early and late-onset Ménière's disease

Purpose

To compare the clinical characteristics of patients with early and late-onset Ménière's disease (MD) and to investigate the impact of psychological factors between the two groups.

Methods

The patients were divided into two groups based on their age of onset: early-onset (<45 years old) and late-onset (>55 years old). The differences in clinical symptoms, auditory, vestibular examination, gadolinium-enhanced MRI, vertigo, and psychological assessment were compared. To assess the severity of vertigo, the Dizziness Handicap Inventory (DHI) and Visual Analogue Scale (VAS) were used. The Patient Health Questionnaire 9-item (PHQ-9) and the Generalized Anxiety Disorder 7-item (GAD-7) scales were used to assess the patient's psychological status.

Results

Thirty-five patients were included in the early-onset and thirty-seven in the late-onset MD groups. Tinnitus was more common in the early-onset group. The aggravating (fatigue) and alleviating (ambient quiet; acute rest) factors of a vertigo episode were statistically different between the two groups. The severity of vestibular endolymphatic hydrops, abnormal rate of canal paresis (CP) value of the caloric test, total DHI score, and VAS score were all higher in the late-onset group. PHQ-9 and GAD-7 scores were significantly correlated with total DHI score in the early-onset group.

Conclusion

Early-onset patients have a higher incidence of tinnitus and are more prone to experience vertigo bouts brought on by fatigue. In late-onset patients, vestibular endolymphatic hydrops are more severe, and the vertigo symptoms are more pronounced. Psychological factors are more closely related to the symptoms of vertigo in early-onset patients.

Morphometric Evaluation of the Facial and Vestibulocochlear Nerves Using MR Imaging in Patients with Menière Disease

BACKGROUND AND PURPOSE

Menière disease (MD) is a condition of unknown etiology, involving genetic predisposition, autoimmune processes, viral infections, cellular apoptosis, and oxidative stress. This study aimed to investigate potential differences in cranial nerves VII and VIII in patients with MD using hydrops MRI (FLAIR) for morphometric evaluations.

MATERIALS AND METHODS

Sequences acquired were 3T MRI, CISS, and 3D FLAIR. We evaluated the morphometrics of cranial nerves VII and VIII from the cerebellopontine angle to the internal auditory canal fundus, comparing the nonaffected and affected sides. Furthermore, we examined the findings in relation to symptom duration and evaluated the feasibility of FLAIR in the morphometry of the cranial nerves.

RESULTS

A total of 53 patients with MD with unilateral symptoms were included. After statistical analysis, no significant differences were found regarding morphometric changes in the affected side compared with the nonaffected side of cranial nerves VII and VIII. There was also no significant difference between the morphometric evaluations of patients with different symptom durations. The morphometric evaluation using hydrops MRI sequences (FLAIR) showed no significant difference compared with established morphometric highly T2-weighted imaging (CISS).

CONCLUSIONS

Our data found no differences in nerve morphometry between clinically nonaffected and affected sides in patients with unilateral MD, nor any correlation with symptom duration. This finding contrasts with previous ones of correlations between clinical features and endolymphatic hydrops. A disease process starting before clinical symptom onset could be a possible explanation. Morphometric evaluation of brain nerves using hydrops MRI sequences is practical and provides similar results compared with T2-weighted imaging, improving patient comfort and reducing MRI scan times.

Contrast Enhancement of Cochlea after Direct Microneedle Intracochlear Injection of Gadodiamide through the Round Window Membrane with Minimal Dosage

RATIONALE AND OBJECTIVES

The potential of contrast-enhanced MRI for diagnosing endolymphatic hydrops is limited by long wait times following intravenous (IV) or intratympanic (IT) delivery, high contrast dosages, and inconsistent signal intensity enhancements. This study investigates microneedle-mediated intracochlear (IC) gadodiamide injection for consistent and efficient contrast delivery with minimal contrast dosage.

MATERIALS AND METHODS

A 100 µm diameter microneedle with 35 µm lumen was used to inject 1 µL of diluted gadodiamide (17.4 mM) into a guinea pig cochlea via the round window membrane. Serial MRI imaging was performed in a post-mortem animal using a 9.4 T small-animal MRI. Maximum intensity projections of MRI scans were generated to visualize diffusion of contrast within cochlea over time; mean intensities in defined regions of interest (ROIs) were calculated. Contrast diffusion time and intensity enhancements were determined.

RESULTS

Contrast was observed in the basal turn of scala tympani (ST) and scala vestibuli (SV) in the first MRI scan for all subjects which was acquired as early as 35 min after injection. Two-tailed paired t-tests confirmed that contrast reached the first two turns of ST and SV within 60 min, and the second half of third turns and apical turns of ST and SV within 90 min (p < 0.05). Intensity enhancements, defined as the percentage increase of the ROI mean intensity in the injection side compared to the contralateral side, exceeded 100% in the first turn and ranged from 12% to 32% in the third and apical turns of ST and SV at 90 min after injection.

CONCLUSIONS

IC gadodiamide enables controllable and efficient contrast delivery with significantly lower contrast dosage, making it a viable alternative for contrast-enhanced cochlear MRI.

3T-3D FLAIR MRI in Menière's disease: associated profiles with clinical symptoms and electroacoustic characteristics

PURPOSE

Diagnosis of Menière's disease relies on clinical symptoms. Injected 3T MRI can show endolymphatic hydrops (EH), but correlation with the clinical status of MD, (probable -PMD or definite-DMD) remains doubtful. We revealed endolymphatic pressure disruption through functional exploration and verified if it was associated with an EH through MRI.

MATERIALS AND METHODS

We prospectively analyzed 3D3T FLAIR MRI of DMD and PMD patients. All of them underwent electrocochleography (EcoG), distortion-product otoacoustic emissions (DPOAEs), and videonystagmograhy (VNG). Amplitudes of summating potential (SP) and cochlear nerve action potential (AP) were measured on EcoG. DPOAE-phase was collected at 1 kHz for the 2f1-f2 DPOAE between sitting and laying position. A SP/AP ≥ 40% and a DPOAE phase-shift > 40° revealed pressure disruption.

RESULTS

39 patients (25 women, 53 y.o. 20-78), were included, with 32 DMD ears and 11 PMD ears. MRI was performed in a median of 21 days [0; 68] from the MD incident. Audiovestibular exploration took place 41 days after the crisis [0;83]. MRI revealed an EH in 71.9% and 27.2% of DMD and PMD, respectively. When combining functional explorations and MRI, testing was positive in 97% for DMD and 82% for PMD. When abnormal (59%), VNG mainly showed hyporeflexia in the diseased ear.

CONCLUSION

In patients suffering from DMD or PMD, with endolymphatic pressure disturbances confirmed by combined DPOAE-phase and EcoG, 3T 3D MRI reveals EH mostly in DMD but rarely in PMD. This seems to confirm that disturbance of endolymphatic pressure precedes EH.

Air-Bone Gap in Meniere's Disease: A Case Series and Literature Review

BACKGROUND/OBJECTIVES

An air-bone gap (ABG) on audiometry is usually secondary to a conductive hearing loss. However, persistent and repeatable ABGs on audiometry in the absence of external or middle ear pathology is thought to arise from inner ear disorders including Meniere's Disease (MD). In this paper, we aim to showcase this interesting finding occurring in MD with an associated literature review.

METHODS

Using retrospective review and analysis of case notes, we describe eight cases of persistent ABG on audiometry in MD. All other causes for the ABG were explored and excluded with the aid of objective audiological testing.

RESULTS

ABG can occur in a small sub-set of the MD population. In our case series, the ABG was typically found to affect the low frequencies. Higher frequencies appear to be spared. However, a detailed history, examination and battery of objective tests are required to ensure that all other causes of the ABG are reliably considered and excluded prior to attributing it to the inner ear. The finding of an ABG in MD may be dependent on the stage of the disease. Further research is required to determine the underlying cause of the ABG and its potential applications to help guide treatment.

Changes in symptom pattern in Meniere's disease by duration: the need for comprehensive management

Purpose

This retrospective study aimed to analyze the symptom profile of Meniere's disease (MD) patients, particularly focusing on the cessation of episodic vertigo and the disease's longitudinal course and the impact of major symptoms on quality of life (QoL).

Methods

The study employed a cross-sectional design and was conducted on 365 out of 560 individuals with definite MD from the Finnish Vestibular and Meniere Federation, utilizing an internet-based questionnaire. Participants were surveyed on vertigo attacks, vestibular drop attacks (VDA), balance issues, selective cognitive complaints, hearing loss, and their effects on overall quality of life (QoL). The study population comprised 79.5% females and 20.5% males, with a mean age of 63 years and an average disease duration of 15.2 years.

Results

The onset of MD was characterized by simultaneous hearing loss, vertigo, and tinnitus in 38% of participants. There was a significant delay in diagnosis for many, with 20% experiencing a delay of over 5 years. The frequency and duration of vertigo attacks generally decreased over time, with attacks becoming shorter and less severe as the disease progressed. Spontaneous remission from episodic vertigo occurred in 34% of participants variably throughout the course of MD. Of the participants 65.5% reported balance issues, and 34% experienced mild VDAs, with severe falls occurring in 10%. VDAs were more common with longer disease duration. Bilateral hearing loss developed in 34.5% of participants over the long term, with a higher risk associated with younger onset age, migraines, and family history of MD. Fatigue, anxiety, and depression were prevalent, particularly among younger participants. Cognitive impairments were linked to the severity of these symptoms and the presence of constant dizziness. QoL was significantly lower among participants with constant dizziness, with factors like fatigue, depression, VDA, and hearing loss contributing to this reduction.

Conclusions

The study highlights the complexity of MD. While vertigo may spontaneously remit, other symptoms such as VDAs, balance issues, cognitive complaints, and hearing loss often persist and worsen over time. Assessing MD solely on primary symptoms like vertigo and hearing loss is insufficient; a comprehensive evaluation is necessary for effective management.

The Role of Pericytes in Inner Ear Disorders: A Comprehensive Review

Inner ear disorders, including sensorineural hearing loss, Meniere's disease, and vestibular neuritis, are prevalent conditions that significantly impact the quality of life. Despite their high incidence, the underlying pathophysiology of these disorders remains elusive, and current treatment options are often inadequate. Emerging evidence suggests that pericytes, a type of vascular mural cell specialized to maintain the integrity and function of the microvasculature, may play a crucial role in the development and progression of inner ear disorders. The pericytes are present in the microvasculature of both the cochlea and the vestibular system, where they regulate blood flow, maintain the blood-labyrinth barrier, facilitate angiogenesis, and provide trophic support to neurons. Understanding their role in inner ear disorders may provide valuable insights into the pathophysiology of these conditions and lead to the development of novel diagnostic and therapeutic strategies, improving the standard of living. This comprehensive review aims to provide a detailed overview of the role of pericytes in inner ear disorders, highlighting the anatomy and physiology in the microvasculature, and analyzing the mechanisms that contribute to the development of the disorders. Furthermore, we explore the potential pericyte-targeted therapies, including antioxidant, anti-inflammatory, and angiogenic approaches, as well as gene therapy strategies.

The relationship between endolymphatic hydrops features and hearing loss in Bilateral Meniere's disease

BACKGROUND

This study aimed to investigate the relationship between the features of endolymphatic hydrops and hearing loss in patients with Bilateral Meniere's Disease.

METHODS

A retrospective analysis was conducted on 77 patients diagnosed with Bilateral Meniere's Disease. The features of endolymphatic hydrops in the affected ear were evaluated through gadolinium-enhanced inner ear Magnetic resonance imaging. The Spearman correlation coefficient, paired t-tests, and Wilcoxon signed-rank tests were employed for data analysis.

RESULTS

The analysis revealed a significant correlation between the degree of endolymphatic hydrops and hearing loss across all frequencies(0.125-8 kHz), including the cochlear, vestibular, and overall degree of endolymphatic hydrops. The strongest correlation between the overall degree of endolymphatic hydrops and hearing loss was observed at low frequencies (r = 0.571, p < 0.05), followed by mid-frequencies (r = 0.508, p < 0.05), and high-frequencies (r = 0.351, p < 0.05), with a correlation of r = 0.463, p < 0.05 for the staging of Meniere's disease. Affected Ears with endolymphatic hydrops both in the cochlea and vestibule exhibited more severe hearing loss and Meniere's disease staging compared to those with isolated endolymphatic hydrops within the same patient.

CONCLUSIONS

The features of endolymphatic hydrops in patients with Bilateral Meniere's Disease were found to correlate with the severity of hearing loss and the staging of Meniere's disease.

The dissociation between pathological caloric testing and a normal video head impulse test helps differentiate between Menière's disease, vestibular migraine, and other vestibular disorders: a confirmatory study in a large cohort of 2,101 patients

Vestibular migraine (VM) and Menière's disease (MD) are characterized by episodes of vertigo of similar duration. It is well known that differentiation between both diseases is not always possible based only on the patient history, physical examination, and audiological testing. In addition, the quantification of the vestibular function can also be helpful since, among patients with MD, there is often a dissociation between a normal/pseudo-normal video head impulse test (vHIT) and reduced caloric testing. The goal of this confirmatory study was to determine the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) of this dissociation to differentiate between MD and VM as well as between MD and other vestibular diseases. We performed a retrospective analysis of 2,101 patients. The examination group consisted of 1,100 patients; of these, 627 (57%) had MD according to the diagnostic criteria of the Bárány Society and 473 (43%) had VM. The comparison group consisted of 1,001 patients with other peripheral, central, or functional vestibular disorders. Statistical analysis revealed the following findings for the dissociation: MD vs. VM: specificity: 83.5%, sensitivity: 58.9%, PPV: 82.6%, and NPV: 60.5%, and MD vs. all other vestibular disorders (VM plus others): specificity: 83.5%, sensitivity: 58.9%, PPV: 60.3%, and NPV: 82.7%. The dissociation between a normal vHIT and a reduced caloric response is due to the high specificity and PPV suited for the differentiation between MD and VM. This part of the study confirms previous findings in a large cohort of patients. When it comes to differentiating between MD and all observed vestibular disorders, if there is no dissociation, the diagnosis of MD is unlikely.

Cluster Analysis to Identify Clinical Subtypes of Ménière's Disease

OBJECTIVE

To identify distinct clinical subtypes of Ménière's disease by analyzing data acquired from a UK registry of patients who have been diagnosed with Ménière's disease.

STUDY DESIGN

Observational study.

METHODS

Patients with Ménière's disease were identified at secondary/tertiary care clinics. Cluster analysis was performed by grouping participants sharing similar characteristics and risk factors into groups based on a defined measure of similarity.

RESULTS

A total of 411 participants were recruited into this study. Two main clusters were identified: participants diagnosed with ear infections (OR = 0.30, p < 0.014, 95% CI: 0.11-0.78) were more likely to be allocated in Cluster 1 (C1). Participants reporting tinnitus in both ears (OR = 11.89, p < 0.001, 95% CI: 4.08-34.64), low pitched tinnitus (OR = 21.09, p < 0.001, 95% CI: 7.47-59.54), and those reporting stress as a trigger for vertigo attacks (OR = 14.94, p < 0.001, 95% CI: 4.54-49.10) were significantly more likely to be in Cluster 2 (C2). Also, participants diagnosed with Benign Paroxysmal Positional Vertigo (OR = 13.14, <0.001, 95% CI: 4.35-39.74), autoimmune disease (OR = 5.97, p < 0.007, 95% CI: 1.62-22.03), depression (OR = 4.72, p < 0.056, 95% CI: 0.96-23.24), migraines (OR = 3.13, p < 0.008, 95% CI: 1.34-7.26), drug allergy (OR = 3.25, p < 0.029, 95% CI: 1.13-9.34), and hay fever (OR = 3.12, p < 0.009, 95% CI: 1.33-7.34) were significantly more likely to be clustered in C2.

CONCLUSIONS

This study supports the hypothesis that Ménière's disease is a heterogeneous condition with subgroups that may be identifiable by clinical features. Two main clusters were identified with differing putative etiological factors.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:3286-3292, 2024.

Functional Level and Dynamic Posturography Results Two Years after Vestibular Neurectomy in Patients with Severe Meniere's Disease

Objectives: The aim of this study was to evaluate the functional outcomes and balance compensation in patients with severe Meniere's disease after vestibular neurectomy. Methods: Pre- and postoperative results were analyzed in twenty patients with unilateral Meniere's disease before and two years after vestibular neurectomy. Clinical evaluation was performed using a subjective grading scale proposed by the American Academy of Otolaryngology-Head and Neck Surgery and the Dizziness Handicap Inventory. Sensory organization test results were analyzed to assess the balance system before and after the surgery. Results: All patients reported a complete resolution of vertigo attacks after the vestibular neurectomy; 95% of patients reported functional level improvement according to a scale proposed by the American Academy of Otolaryngology-Head and Neck Surgery, and the average score decreased from 4.5 to 1.6. Clinical improvement, evaluated with the Dizziness Handicap Inventory, was present in all patients, with the average result decreasing from 81.7 to 16.4. Analyzing both grading systems, differences between pre- and postoperative results were statistically significant. No statistically significant differences were found between the sensory organization test results before and after vestibular neurectomy. Significant correlations were found between a patient's age and postoperative results of the Dizziness Handicap Inventory and posturography. Conclusions: Vestibular neurectomy is an effective vertigo treatment in patients with severe Meniere's disease with no clinical improvement despite conservative treatment. It results in subjective physical, functional, and emotional improvement, enabling patients to return to daily activities and work. An appropriate qualification of patients and comprehensive preoperative evaluation are essential to obtaining satisfactory clinical outcomes.

Efficacy of endolymphatic duct blockage in treating Ménières disease

OBJECTIVES

Ménière's disease (MD) is an idiopathic inner ear disorder characterized by recurrent episodes of episodic rotational vertigo, fluctuating hearing loss, tinnitus, and a feeling of ear stuffiness. Endolymphatic sac (ES)-related surgery is used primarily in patients with MD who have failed to respond to pharmacologic therapy. Endolymphatic duct blockage (EDB) is a new procedure for the treatment of MD, and related clinical studies are still scarce. This study aims to investigate the dynamic changes in endolymphatic hydrops (EH) and the long-term surgical outcomes in MD patients undergoing EDB, and to evaluate the impact of different types of ES on the surgical efficacy.

METHODS

A retrospective analysis was conducted on 33 patients with refractory MD who underwent EDB. Based on the morphology of their endolymphatic sacs, patients were divided into a normal-type group (n=14) and an atrophic-type group (n=19). The frequency of vertigo symptoms, hearing, vestibular function, and the dynamic changes of gadolinium-enhanced MRI of the inner ear were compared were compared before and after surgery between the 2 groups.

RESULTS

Compared with the atrophic-type group, the patients in the normal-type group had a higher rate of complete vertigo control, better cochlear and vestibular function, and a lower endolymph to vestibule volume ratio (all P<0.05). In addition, 7 patients in the normal-type group were found to have reversal of EH, while no reversal of EH was detected in the atrophic-type group after surgery.

CONCLUSIONS

The response to EDB treatment varies between normal and atrophic MD patients, suggesting that the 2 pathological types of endolymphatic sacs may have different underlying mechanisms of disease.

Mendelian randomization analysis does not reveal a causal association between migraine and Meniere's disease

Background

According to observational research, migraine may increase the risk of Meniere's disease (MD). The two have not, however, been proven to be causally related.

Methods

Using Mendelian random (MR) analysis, we aimed to evaluate any potential causal relationship between migraine and MD. We extracted single-nucleotide polymorphisms (SNPs) from large-scale genome-wide association studies (GWAS) involving European individuals, focusing on migraine and MD. The main technique used to evaluate effect estimates was inverse-variance weighting (IVW). To assess heterogeneity and pleiotropy, sensitivity analyses were carried out using weighted median, MR-Egger, simple mode, weighted mode, and MR-PRESSO.

Results

There was no discernible causative link between genetic vulnerability to MD and migraine. The migraine dose not increase the prevalence of MD in the random-effects IVW method (OR = 0.551, P = 0.825). The extra weighted median analysis (OR = 0.674, P = 0.909), MR-Egger (OR = 0.068, P = 0.806), Simple mode (OR = 0.170, P = 0.737), and Weighted mode (OR = 0.219, P= 0.760) all showed largely consistent results. The MD dose not increase the prevalence of migraine in the random-effects IVW method (OR = 0.999, P = 0.020). The extra weighted median analysis (OR = 0.999, P = 0.909), MR-Egger (OR = 0.999, P = 0.806), Simple mode (OR = 0.999, P = 0.737), and Weighted mode (OR = 1.000, P = 0.760).

Conclusion and significance

This Mendelian randomization study provides casual evidence that migraine is not a risk factor for MD and MD is also not a risk factor for migraine.

Vestibular dysfunction leads to cognitive impairments: State of knowledge in the field and clinical perspectives (Review)

The vestibular system may have a critical role in the integration of sensory information and the maintenance of cognitive function. A dysfunction in the vestibular system has a significant impact on quality of life. Recent research has provided evidence of a connection between vestibular information and cognitive functions, such as spatial memory, navigation and attention. Although the exact mechanisms linking the vestibular system to cognition remain elusive, researchers have identified various pathways. Vestibular dysfunction may lead to the degeneration of cortical vestibular network regions and adversely affect synaptic plasticity and neurogenesis in the hippocampus, ultimately contributing to neuronal atrophy and cell death, resulting in memory and visuospatial deficits. Furthermore, the extent of cognitive impairment varies depending on the specific type of vestibular disease. In the present study, the current literature was reviewed, potential causal relationships between vestibular dysfunction and cognitive performance were discussed and directions for future research were proposed.

Efficacy of 100 hz sound stimulation on saccular dysfunction in meniere's disease

BACKGROUND

Although various medical remedies have been attempted to alleviate the symptoms of Meniere's disease (MD), the risk-benefit ratios of these various treatments remain debatable.

OBJECTIVE

We investigated the efficacy of sound stimulation of 100 Hz for treating vestibular dysfunction in patients with Meniere's disease (MD).

MATERIALS AND METHODS

Patients with definitive MD with intractable vestibular symptoms and endolymphatic hydrops (EH) in the inner ear were evaluated. The experimental group received sound stimulation of 75 dB at a frequency of 100 Hz for 5 min, and the control group received sound stimulation of 75 dB at a frequency of 250 Hz for 5 min. Cervical vestibular-evoked myogenic potentials (cVEMPs) were measured before and after each sound stimulation, and the results of the clinical tests were compared between the two patient groups.

RESULTS

Significant increases in cVEMP amplitudes were observed after sound stimulation of 100 Hz in ears with vestibular endolymphatic hydrops, although no such improvement was observed in the control group.

CONCLUSION

Sound stimulation of 75 dB at a frequency of 100 Hz leads to improvement in cVEMP amplitude in patients with definitive MD. Adequate sound stimulation might be a new method for treating vestibular dysfunction associated with MD.

Acute histological reactions in the otolith organs to inner ear drug delivery through a cochlear implant

Introduction

Cochlear implantation is currently regarded as a safe and minimally invasive procedure. However, cochlear implantation can have an impact on vestibular function, despite the lack of correlation between patient symptomatology and damage in vestibular tests. Thus, the present study aims to analyze the presence of hydrops and histological reactions at the level of the vestibule after cochlear implantation with dexamethasone pump delivery in Macaca fascicularis (Mf).

Materials and methods

A detailed histological study was conducted on a total of 11 Mf. All 11 Mf were divided into three groups: 5 Mf were implanted with an electrode array HL-14 connected to a pump delivering FITC-dextran for 24 h (Group A); 4 Mf were implanted with a CI electrode array attached to a pump for FITC-dextran delivery for 7 days (Group B); and 2 Mf were considered the control group, without any kind of cochlear device implantation (Group C). After drug deliver, the selected macaques were euthanized to collect tissue samples for histological analysis. An experienced observer, focusing on the utricle and saccule areas, conducted a blinded inner ear histology analysis.

Results

Surgical procedures were successfully performed in all cases. No signs of cochlear reaction to the device were observed, including neither collapse nor fibrosis. Endolymphatic sinus dilatation was observed in Mf4A and Mf3B, while cochlear hydrops was observed in Mf3A. The mean areas of the utricle and saccule exhibited some statistically significant differences, specifically, in the saccule between groups C and both groups A (p = 0.028) and B (p = 0.029); however, no significant differences were observed between groups A and B or among comparisons of the utricle.

Discussion

A significant concern relates to the safety of cochlear implantation with regard to vestibular preservation and hearing. New advancements in electrode arrays, such as CI devices coupled with delivery pumps, pose a challenge in maintaining minimally traumatic surgical concept-based procedures without affecting the inner ear homeostasis. The implantation of this device may cause vestibular hydrops in the saccule, indicating that the longer the time of substance release, the greater the grade of hydrops evidenced at the saccular level. Apart from this finding, the risk of histological damage to the vestibule is low.

Therapeutic Response of Meniere's Disease Utilizing Sorbus domestica

Introduction Meniere's disease (MD) is a chronic condition characterized by episodic attacks of vertigo, fluctuating hearing loss, and tinnitus. MD can impart a significant socioeconomic impact with associated progressive hearing loss. First-line therapies consist of diuretics and antihistamines, with second-line therapies including intratympanic steroids and pulse therapy. Third-line treatments include endolymphatic sac surgery (ELSS) followed by intratympanic gentamicin injection and/or vestibular neurectomy. The gemmotherapy Sorbus domestica's inherent properties to regulate venous circulation and lymphatic drainage have been utilized in the European literature for the treatment of MD and the patients in this study. Methods Patients presenting for rehabilitation at Pulaski Health and Rehabilitation Facility with a history of vertigo were examined and, through history and specific exam, to define MD. This resulted in six patients whose symptoms and exam were consistent with MD and interfered with their therapeutic progression. These patients were offered and accepted treatment with Sorbus domestica for their MD. Results All patients responded with either resolution or significant improvement in their symptoms and hearing loss. Treatment also resulted in an improved and probably shortened rehabilitative course. All patients had no adverse reactions and were supplied with resources for continual treatment upon discharge. Conclusion Sorbus domestica is a safe and viable treatment option for MD. It has been useful, especially in treatment-resistant diseases, without side effects and can be utilized in initial cases with improvement or resolution of hearing loss.

Stratification of patients with Menière's disease based on eye movement videos recorded from the beginning of vertigo attacks and contrast-enhanced MRI findings

Purpose

Diagnosis of Menière's disease (MD) relies on subjective factors and the patients diagnosed with MD may have heterogeneous pathophysiologies. This study aims to stratify MD patients using two objective data, nystagmus videos and contrast-enhanced magnetic resonance imaging (CE-MRI).

Methods

This is a retrospective cross-sectional study. According to the Japan Society for Equilibrium Research criteria (c-JSER), adults diagnosed with definite MD and who obtained videos recorded by portable nystagmus recorder immediately following vertigo attacks and underwent CE-MRI of the inner ear were included (ss = 91). Patients who obtained no nystagmus videos, who had undergone sac surgery, and those with long examination intervals were excluded (n = 40).

Results

The gender of the subjects was 22 males and 29 females. The age range was 20-82 y, with a median of 54 y. Endolymphatic hydrops (EH) were observed on CE-MRI in 84% (43 patients). Thirty-one patients had unilateral EH. All of them demonstrated EH on the side of the presence of cochlear symptoms. The number of patients who had both nystagmus and EH was 38. Five patients only showed EH and 5 patients only exhibited nystagmus, while 3 patients did not have either. Of the 43 nystagmus records, 32 showed irritative nystagmus immediately after the vertigo episode. The direction of nystagmus later reversed in 44% of cases over 24 h.

Conclusion

Patients were stratified into subgroups based on the presence or absence of EH and nystagmus. The side with cochlear symptoms was consistent with EH. The c-JSER allows for the diagnosis of early-stage MD patients, and it can be used to treat early MD and preserve hearing; however, this approach may also include patients with different pathologies.

Enhancing the therapeutic potential of intravenous glycerol for Meniere's disease: Robust results from an extensive patient cohort

INTRODUCTION

Meniere's disease (MD) is an idiopatic condition characterized by recurrent attacks of vertigo, hearing loss, tinnitus, and aural fullness, affecting quality of life. Intravenous glycerol has shown potential as a therapeutic option. This study evaluates its efficacy in a larger patient cohort.

MATERIALS AND METHODS

Retrospective study with 168 patients having unilateral MD unresponsive to dietary restrictions. Intravenous 10 % glycerol with 0.9 % sodium chloride was administered for six months. Audio-vestibular assessments and questionnaires were used.

RESULTS

Significant improvements in vertigo control observed. 7.1 % achieved complete control, and 58.3 % had substantial control. Quality of life measures improved, and audiometry thresholds remained unchanged. No major adverse events reported.

DISCUSSION

Intravenous glycerol effectively controlled vertigo and improved MD patients' quality of life. Limitations include lack of a control group and a relatively short-term follow-up. Future prospects include randomized controlled trials and optimization of treatment protocols.

CONCLUSION

Intravenous glycerol shows promise as a therapeutic option for MD, with notable improvements in vertigo control and quality of life. Further research is needed for validation and optimization.

Identifying Predictors of Treatment Response in Meniere's Disease: A Clinical Severity Staging System

OBJECTIVE

Identify clinically important factors associated with conservative treatment response in Meniere's disease and incorporate these factors into a composite clinical severity staging system.

STUDY DESIGN

Retrospective cohort.

SETTING

Tertiary academic medical center.

METHODS

Adult patients newly diagnosed with Meniere's disease between January 1, 2016 and December 31, 2019 were eligible. Patients with previous treatment for Meniere's disease, prior otologic surgery, or a lack of follow-up data were excluded. Treatment-responsive patients were managed with only conservative therapies (eg, dietary modifications, diuretics) and unresponsive patients underwent more intensive therapies (eg, intratympanic procedures, surgical interventions).

RESULTS

Of 78 patients included in the study, 49 (63%) were responsive to conservative therapies and 29 (37%) were not. Responsive patients had higher proportions of no or mild vertigo (24%, 95% confidence interval [CI]: 3.1%-45.8%) and none or mild comorbidity (27%, 95% CI: 9.2%-44.7%) and a lower proportion of hearing loss (19%, 95% CI: 5.6%-32.4%) compared to unresponsive patients. Conjunctive consolidation of these 3 factors was performed to develop a three-stage system with a treatment response gradient ranging from 100% to 64% to 18% for stage 1 (n = 11), stage 2 (n = 56), and stage 3 (n = 11), respectively.

CONCLUSIONS

This study identified decreased vertigo severity, reduced comorbidity burden, and absence of hearing loss as factors associated with conservative treatment response in Meniere's disease. A composite clinical severity staging system including these 3 factors can be used to optimize treatment selection and promote patient-centered management of Meniere's disease.

The value of gadolinium-enhanced MRI in predicting the development of sudden hearing loss into Ménière's disease

OBJECTIVE

To compare the clinical features of sudden hearing loss (SHL) in patients with and without endolymphatic hydrops (EH), and to investigate the association between SHL with EH and Ménière's disease (MD).

METHODS

The clinical data of 63 SHL patients with first symptoms were evaluated retrospectively. Patients were separated into two groups based on the results of gadolinium-enhanced magnetic resonance imaging: EH and non-EH groups. Independent sample t-test and U-test were used to compare groups for continuous variables, and the chi-squared test, corrected chi-squared test and Bonferroni correction test were used to compare groups for binary and ordinal variables. The binary logistic regression model was utilised for univariate and multivariate analysis of follow-up patient prognosis.

RESULTS

The EH and non-EH groups contained 32 and 31 patients, respectively. The EH group had a higher prevalence of low-tone descending hearing loss. Fifty-one patients were followed for more than 2 years. In the EH group, 11 and 15 patients were diagnosed with sudden sensorineural hearing loss (SSNHL) and MD, respectively, while in the non-EH group, 24 patients were diagnosed with SSNHL and only one with MD. EH, low-tone descending hearing loss and vertigo were risk factors for the diagnosis of MD in a subgroup univariate regression analysis of patients experiencing SHL. EH was found to be a risk factor for the progression of SHL into MD in a multifactor regression analysis.

CONCLUSIONS

Patients with SHL who have EH are more likely to present with low-tone descending hearing loss. EH is a risk factor for the subsequent development of MD.

Efficacy and preservation of hearing with low-dose gentamicin in unilateral meniere's disease: A clinical symptomatology-based study

PURPOSE

Meniere's disease (MD), a disorder of the inner ear, presents numerous therapeutic challenges, and intratympanic (IT) gentamicin has been proposed for intractable cases. However, controversy regarding dosage and method persists. The purpose of this study was to assess the efficacy and safety of low-dose IT gentamicin on vertigo attacks in MD using a clinical symptomatology-based method, wherein administration was repeated only if vertigo attacks recurred, with a 2-week interval between injections.

MATERIALS AND METHODS

This study included 88 patients with unilateral intractable MD. All patients received one to five IT injections with 0.5 ml of 10 mg of gentamicin (80 mg/2 ml) with an interval of 2 weeks between injections. Vertigo attacks were evaluated before and after therapy and categorized into classes A-F according to the 2015 Equilibrium Committee criteria. Audiovestibular assessments, including Pure Tone Audiometry and Vestibulo-Ocular Reflex evaluations, were performed.

RESULTS

Before treatment, patients had an average of 4.4 vertigo attacks/month; after treatment, this average decreased to 0.52. The majority of patients (57 %) reached Class A or B vertigo control with five or fewer gentamicin injections. VOR gain was slightly affected on the healthy side and significantly reduced on the affected side. No hearing deterioration was found in any of the treated patients.

CONCLUSIONS

Low-dose IT gentamicin administration based on clinical symptomatology can produce a satisfactory control of vertigo attacks after treatment. This protocol primarily affected the vestibular function, as demonstrated by the significant reduction in VOR gain on the affected side, while avoiding cochlear damage. The lack of adverse events and preservation of hearing underscore the safety and efficacy of this method. These findings have significant clinical implications, suggesting that a low-dose, clinical symptomatology-based gentamicin treatment regimen could be an effective and safe strategy for managing unilateral Meniere's disease in a larger population.

Vestibular Drop Attack: An Analysis of the Therapeutic Response

The present study evaluates the response to betahistine in patients who presented vestibular drops attacks in the context of Ménière's disease (MD) and the factors that can predict an unfavorable response to it. A total of 43 patients were analyzed, out of which 33 were diagnosed with MD. This is a descriptive, cross-sectional study with retrospective data collection. Data as regards age, accompanying symptoms, etiological diagnosis and response to MD treatment were collected. A statistical analysis was carried out, and we found that the disease evolution time and specific alterations in the vestibulospinal and oculomotor physical examination present an unfavorable response to betahistine. Failures for betahistine were treated with intratympanic gentamicin, with which symptomatic control was achieved in all cases.

Research advances in cochlear pericytes and hearing loss

Pericytes are specialized mural cells surrounding endothelial cells in microvascular beds. They play a role in vascular development, blood flow regulation, maintenance of blood-tissue barrier integrity, and control of angiogenesis, tissue fibrosis, and wound healing. In recent decades, understanding of the critical role played by pericytes in retina, brain, lung, and kidney has seen significant progress. The cochlea contains a large population of pericytes. However, the role of cochlear pericytes in auditory pathophysiology is, by contrast, largely unknown. The present review discusses recent progress in identifying cochlear pericytes, mapping their distribution, and defining their role in regulating blood flow, controlling the blood-labyrinth barrier (BLB) and angiogenesis, and involvement in different types of hearing loss.

Current definition, diagnosis, and treatment of canine and feline idiopathic vestibular syndrome

Idiopathic vestibular syndrome (IVS) is one of the most common neurological disorders in veterinary medicine. However, its diagnosis and treatment varies between publications. The aim of the current study was to gather experts' opinion about IVS definition, diagnosis, and treatment. An online-survey was used to assess neurology specialists' opinion about the definition, diagnosis and treatment of IVS. The study demonstrated that the definition, diagnosis, and treatment of IVS are largely consistent worldwide, with the EU prioritising less frequently advanced imaging and more often otoscopy to rule out other diseases. IVS was defined by most specialists as an acute to peracute, improving, non-painful peripheral vestibular disorder that often affects cats of any age and geriatric dogs. Regarding diagnosis, a detailed neurological examination and comprehensive blood tests, including thyroid values, blood pressure, and otoscopic examination, was seen as crucial. A thorough workup may also involve MRI and CSF analysis to rule out other causes of vestibular dysfunction. Treatment of IVS typically involved intravenous fluid therapy and the use of an antiemetic, with maropitant once daily being the preferred choice among specialists. Antinausea treatment was considered, however, only by a handful specialists. This survey-based study provides valuable insights from neurology experts and highlights areas that require further research to bridge the gap between theory and practice.

Magnetic Resonance Volumetric Quantification of Vestibular Endolymphatic Hydrops in Patients with Unilateral Definite Meniere's Disease Using 3D Inversion Recovery with Real Reconstruction (3D-REAL-IR) Sequence

BACKGROUND

The 3D-REAL-IR MRI sequence allows for an in vivo visualization of endolymphatic hydrops. Qualitative assessment methods of the severity of vestibular and cochlear hydrops are the most commonly used.

METHODS

A quantitative volumetric measurement of vestibular EH in patients with definite unilateral Ménière's disease using the 3D-REAL-IR sequence and the calculation of the endolymphatic ratio (ELR) was intended.

RESULTS

Volumetric calculations of the vestibules, vestibular endolymph and vestibular ELR are performed in 96 patients with unilateral Ménière's disease and correlated with classic qualitative grading scales.

CONCLUSIONS

Quantitative volumetric measurement of vestibular hydrops using the 3D-REAL-IR sequence is feasible and reproducible in daily clinical practice. Vestibular ELR values exceeding 60% defined radiologically significant vestibular hydrops, while values below 30% defined radiologically non-significant vestibular hydrops.

Mass Spectrometric Interrogation of Earwax: Toward the Detection of Ménière's Disease

Many diseases remain difficult to identify because the occurrence of characteristic biomarkers within traditional matrices such as blood and urine remain unknown. Disease diagnosis could, therefore, benefit from the analysis of readily accessible, non-traditional matrices that have a high chemical content and contain distinguishing biomarkers. One such matrix is cerumen (i.e., earwax), whose chemical complexity can pose challenges when analyzed by conventional methods. A combination of cerumen chemical profiles analyzed by gas chromatography-mass spectrometry (GC-MS) and direct analysis in real time-high-resolution mass spectrometry (DART-HRMS) were investigated to ascertain the possible presence of the rare otolaryngological disorder Ménière's disease. This illness is currently identified via "diagnosis by exclusion" in which the disease is distinguished from others with overlapping symptoms by the process of elimination. GC-MS revealed a chemical profile difference between those with and without a Ménière's disease diagnosis by a visually apparent diminution of the compounds present in the Ménière's disease samples. DART-HRMS revealed that the two classes could be differentiated using three fatty acids: cis-9-hexadecenoic acid, cis-10-heptadecenoic acid, and cis-9-octadecenoic acid. These compounds were subsequently quantified by GC-MS and overall, the amounts of these fatty acids were decreased in Ménière's disease patients. The average levels for non-Ménière's disease samples were 7.89 μg/mg for cis-9-hexadecenoic acid, 0.87 μg/mg for cis-10-heptadecenoic acid, and 4.94 μg/mg for cis-9-octadecenoic acid. The average levels for Ménière's disease samples were 1.70 μg/mg for cis-9-hexadecenoic acid, 0.13 μg/mg for cis-10-heptadecenoic acid, and 2.07 μg/mg for cis-9-octadecenoic acid. The confidence levels for cis-9-hexadecenoic acid, cis-10-heptadecenoic acid, and cis-9-octadecenoic acid were 98.7%, 99.9%, and 95.4%, respectively. The results suggest that assessment of the concentrations of these fatty acids could be a useful clinical tool for the more rapid and accurate detection of Ménière's disease.

Associations Among Medical Therapy, SelfAdministered Exercise, and Characteristics of Ménière's Disease

BACKGROUND

The aim of the current study was to explore the associations among different therapeutic procedures, self-administered exercise, and characteristics of Ménière's disease.

METHODS

The study used a retrospective design and included 539 people with Ménière's disease who were focusing on self-administered exercise. The mean age and history of Ménière's disease among these participants were 61.9 years and 15.6 years, respectively. Of the participants, 79.5% were female. The data were collected by an electronic questionnaire that focused on symptoms of Ménière's disease, exercise and training habits, balance problems, impacts of the complaints, quality of life, medical treatment, physiotherapy, and psychotherapy.

RESULTS

Of the participants, 79.3% used medical treatment. Betahistine (56.8%) was the most popular followed by periodical anti-emetic use (41.0%) and diuretics (22.4%). Of the participants 70% were doing some self-administered training. The frequency of training depended on age, severity of balance problems, vestibular drop attacks, and gait problems. The type of training depended on age, quality of life, vestibular drop attacks, and gait problems. No association was found between vertigo and frequency/type of balance training.

CONCLUSION

The use or effect of therapeutic procedures for Ménière's disease patients was not related to symptoms experienced. Most participants with Ménière's disease used training programs that aimed to alleviate their condition, especially balance-, gait-, and vestibular drop attack-associated problems. Patient support organizations should be working to help characterize the types of balance disorders people are dealing with in order to individually tailor a rehabilitation program to the patient's needs.

Pathophysiological analysis of idiopathic sudden sensorineural hearing loss by magnetic resonance imaging: A mini scoping review

Objective

To summarize the pathophysiological analysis of idiopathic sudden sensorineural hearing loss (ISSNHL) by magnetic resonance imaging (MRI), focusing on the findings of high signal or endolymphatic hydrops (EH) in the inner ear.

Methods

We summarize the published studies of our research group regarding the pathophysiological analysis of ISSNHL on MRI and review related clinical articles that have reported significantly high signal or the existence of EH in ears with ISSNHL.

Results

Pre-contrast high signal on MRI may indicate minor hemorrhage or increased permeability of surrounding vessels to the perilymph, whereas post-contrast high signal indicates breakdown of the blood-labyrinth barrier, in which irreversible changes would lead to poor prognosis. In some cases of ISSNHL, primary EH could be pre-existing and may be a risk factor for the onset of ISSNHL.

Conclusion

Analysis of ISSNHL by cutting-edge MRI evaluation could provide useful information for elucidating its pathophysiology and for predicting prognosis in this disease.

The value of 3D quantitative scoring of endolymphatic hydrops in the diagnosis and differential diagnosis of Ménière's disease

Objective

We aimed to explore the application of three-dimensional (3D) quantitative scoring of endolymphatic hydrops (EH) based on gadolinium-contrast MRI in both the diagnosis and differential diagnosis of Ménière's disease (MD).

Methods

Local threshold method based on signal intensities was used to quantitatively measure volumes, and the degree of EH was scored by 3D quantitative scoring. The receiver-operating characteristic (ROC) curve was used to compare the diagnostic efficacy of this method against conventional evaluation methods. The scores of MD, sudden sensorineural hearing loss (SSNHL), delayed endolymphatic hydrops (DEH), and vestibular migraine (VM) group were compared and correlated with clinical examination results, including pure tone audiometry (PTA), electrocochleogram, and caloric test.

Results

The sensitivity and specificity of 3D quantitative scoring were 94.1% and 92.2%, while conventional evaluation methods were 84.3% and 88.2%, respectively. Cochlear score (CR), vestibular score (VR), semicircular canal score (SR), and total scores (TR) in MD group were significantly higher than those in SSNHL group. The rate of diagnosis of MD was significantly higher in the MD group (92.2%) than VM group (27.3%). In MD, PTA was significantly correlated with CR and SR, the ratio of summating potential to action potential (-SP/AP) of electrocochleogram was significantly correlated with CR, VR, and SR, also canal paresis (CP) value of caloric test was significantly correlated with SR.

Conclusion

3D quantitative scoring demonstrated better diagnostic efficacy than conventional evaluation methods for Ménière's disease, and it may be an effective clinical tool to distinguish MD from SSNHL and VM. The clinical practicality of inner ear-enhanced MRI was further confirmed.

Level of Evidence

IV.

Comparison between audio-vestibular findings and contrast-enhanced MRI of inner ear in patients with unilateral Ménière’s disease

Objective

The diagnosis of Ménière’s disease (MD), characterized by idiopathic endolymphatic hydrops (ELH), remains a clinical priority. Many ancillary methods, including the auditory and vestibular assessments, have been developed to identify ELH. The newly emerging delayed magnetic resonance imaging (MRI) of the inner ear after intratympanic gadolinium (Gd) has been used for identifying ELH in vivo. We aimed to investigate the concordance of audio-vestibular and radiological findings in patients with unilateral MD.

Methods

In this retrospective study, 70 patients with unilateral definite MD underwent three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequences following intratympanic application of Gd. Audio-vestibular evaluations were performed, including pure tone audiometry, electrocochleogram (ECochG), glycerol test, caloric test, cervical and ocular vestibular evoked myogenic potentials (VEMPs), and video head impulse test (vHIT). The relationship between imaging signs of ELH and audio-vestibular results was investigated.

Results

The incidence of radiological ELH was higher than that of neurotological results, including the glycerol test, caloric test, VEMPs, and vHIT. Poor or slight agreement was observed between audio-vestibular findings and radiological ELH in cochlear and/or vestibular (kappa values &lt;0.4). However, the pure tone average (PTA) in the affected side significantly correlated with the extent of both cochlear (r = 0.26795, p = 0.0249) and vestibular (r = 0.2728, p = 0.0223) hydrops. Furthermore, the degree of vestibular hydrops was also positively correlated with course duration (r = 0.2592, p = 0.0303) and glycerol test results (r = 0.3944, p = 0.0061) in the affected side.

Conclusion

In the diagnosis of MD, contrast-enhanced MRI of the inner ear is advantageous in detecting ELH over the conventional audio-vestibular evaluations, which estimates more than hydropic dilation of endolymphatic space.

A bibliometric and visualization study of Meniere's disease: Current status and global hotspots and emerging trends

BACKGROUND

Meniere's disease (MD) is a clinical condition characterized by endolymphatic hydrops. Persistent symptoms negatively affect patients mood, and the underlying etiology remains unclear. It is necessary to comprehensively understand the relevant publications, review the history and current status of research, and analyze hotspots and frontiers of research on MD.

METHODS

We retrieved literature on Meniere's disease from 2003 to 2022 from the Web of Science database and extracted the data. Data visualization and analysis was conducted using Cite Space, VOS viewer, an online web tool, and Microsoft Office Power Point 2019.

RESULTS

In total, 2847 publications were analyzed. The number of annual publications was relatively stable, with an accelerated upward trend over the past 5 years. The country with the most publications was USA (751, 26.38%), while the University of Munich contributed more publications than any other institution (117, 4.11%). The article titled "Diagnostic criteria for Meniere's disease" by Lopez-Escamez J et al in 2015 was the most cited and co-cited publication, and also had the top co-cited references with the strongest citation bursts. Naganawa S was the author with the most publications (85, 2.99%). The top 3 journals and co-cited journals were Otology Neurotology, Acta Oto Laryngologica, and Laryngoscope. Recently, the key theme words were "sensorineural hearing loss," "therapy," "intratympanic injection method," "vestibular-evoked myogenic potentials," "vestibular migraine," "magnetic resonance imaging," and "meniere's disease."

CONCLUSIONS

The US has the largest number of publications and research institutions, many European countries have high-quality journals, and Japan has the highest number of scholars. The international opinion on Meniere's disease is relatively uniform. The stepped-therapy for MD is scientific and clear. Intratympanic injection of steroids and intratympanic injection of gentamicin are commonly used, but steroids are considered safer. Saccular dysfunction may be more common in patients with MD than in those with utricular dysfunctions. It is worth paying attention to study the relationship between MD and vestibular migraine through headache. Progress in magnetic resonance imaging technology is still required for the imaging diagnosis of MD.

In Silico Localization of Perilymph Proteins Enriched in Meńier̀e Disease Using Mammalian Cochlear Single-cell Transcriptomics

Hypothesis

Proteins enriched in the perilymph proteome of Meńier̀e disease (MD) patients may identify affected cell types. Utilizing single-cell transcriptome datasets from the mammalian cochlea, we hypothesize that these enriched perilymph proteins can be localized to specific cochlear cell types.

Background

The limited understanding of human inner ear pathologies and their associated biomolecular variations hinder efforts to develop disease-specific diagnostics and therapeutics. Perilymph sampling and analysis is now enabling further characterization of the cochlear microenvironment. Recently, enriched inner ear protein expression has been demonstrated in patients with MD compared to patients with other inner ear diseases. Localizing expression of these proteins to cochlear cell types can further our knowledge of potential disease pathways and subsequent development of targeted therapeutics.

Methods

We compiled previously published data regarding differential perilymph proteome profiles amongst patients with MD, otosclerosis, enlarged vestibular aqueduct, sudden hearing loss, and hearing loss of undefined etiology (controls). Enriched proteins in MD were cross-referenced against published single-cell/single-nucleus RNA-sequencing datasets to localize gene expression to specific cochlear cell types.

Results

In silico analysis of single-cell transcriptomic datasets demonstrates enrichment of a unique group of perilymph proteins associated with MD in a variety of intracochlear cells, and some exogeneous hematologic and immune effector cells. This suggests that these cell types may play an important role in the pathology associated with late MD, suggesting potential future areas of investigation for MD pathophysiology and treatment.

Conclusions

Perilymph proteins enriched in MD are expressed by specific cochlear cell types based on in silico localization, potentially facilitating development of disease-specific diagnostic markers and therapeutics.

Temporal changes in endolymphatic hydrops on MRI with or without intervention: A systematic review

OBJECTIVE

The pathophysiology of Meniere's Disease (MD) involves endolymphatic hydrops (ELH) of the inner ear. Magnetic Resonance Imaging (MRI) has been shown to detect ELH, but changes in ELH have been poorly described using this modality. Our objective was to review MRI-measured changes in ELH over time and after medical and/or surgical intervention in patients with MD. We secondarily aim to associate changes in ELH with changes in MD symptomatology.

DATABASES REVIEWED

Medline, Web of Science, and Embase databases.

METHODS

A systematic review of articles was performed to identify studies utilizing MRI to measure ELH changes over time, and after medical or surgical treatment. Articles on non-human subjects and without direct measurement of ELH were excluded.

RESULTS

Of 532 studies identified, 12 were included, involving 170 patients (mean age 56.3 years). Ten studies were prospective; two were retrospective. Five studies strictly utilized medical means of intervention, four utilized surgical treatments, one utilized both, and two observed temporal changes without treatment. Across all interventions, 72.1 % of patients exhibited the same or worsening ELH on imaging. In studies reporting vertigo outcomes, 95.9 % of patients exhibited improvement after the treatment period.

CONCLUSION

Medical and surgical interventions often yield symptomatic relief of vertigo in MD patients despite stable or increasing ELH volume. MRI may have greater clinical utility in diagnosing ELH as opposed to assessing treatment response.

Vestibular and audiometric results after endolymphatic mastoid shunt surgery in patients with Menière's disease

PURPOSE

Treatment of Menière's Disease (MD) comprises an array of both non-destructive and destructive treatment options. In patients who are therapy-refractory to non-destructive medical treatment, endolymphatic mastoid shunt surgery (EMSS) is both recommended and debated controversially. The aim of this study was to investigate safety in terms of hearing, vestibular function, complication rate, and efficacy with regards to vertigo control of EMSS in patients with MD according to the current diagnostic criteria of 2015.

METHODS

Retrospective analysis of 47 consecutive patients with definite or probable MD with description of demographic parameters, pre- and postoperative MD treatment, pre- and postoperative audiometric (pure tone audiometry) and vestibular (caloric testing) results. The parameters were compared between patients with and without postoperative vertigo control.

RESULTS

31/47 patients (66.0%) had improved vertigo control postoperatively. Postoperative hearing and vestibular preservation were predominantly stable. No significant differences between patients with improved vertigo control and patients with no change or worse vertigo episodes were found. In the treatment refractory group, 4 patients required a revision EMSS and 6 a destructive MD treatment (5 gentamicin intratympanically, 1 labyrinthectomy). No peri- or postsurgical complications were reported.

CONCLUSIONS

EMSS was found to be beneficial in two thirds of the patients with definite or probable Morbus Menière and a safe procedure regarding hearing and vestibular preservation with no postoperative complications. Therefore, EMSS should be considered before inducing destructive treatment options, such as intratympanic gentamicin application or labyrinthectomy.

Development and In-Silico and Ex-Vivo Validation of a Software for a Semi-Automated Segmentation of the Round Window Niche to Design a Patient Specific Implant to Treat Inner Ear Disorders

The aim of this study was to develop and validate a semi-automated segmentation approach that identifies the round window niche (RWN) and round window membrane (RWM) for use in the development of patient individualized round window niche implants (RNI) to treat inner ear disorders. Twenty cone beam computed tomography (CBCT) datasets of unilateral temporal bones of patients were included in the study. Defined anatomical landmarks such as the RWM were used to develop a customized 3D Slicer™ plugin for semi-automated segmentation of the RWN. Two otolaryngologists (User 1 and User 2) segmented the datasets manually and semi-automatically using the developed software. Both methods were compared in-silico regarding the resulting RWM area and RWN volume. Finally, the developed software was validated ex-vivo in N = 3 body donor implantation tests with additively manufactured RNI. The independently segmented temporal bones of the different Users showed a strong consistency in the volume of the RWN and the area of the RWM. The volume of the semi-automated RWN segmentations were 48 ± 11% smaller on average than the manual segmentations and the area of the RWM of the semi-automated segmentations was 21 ± 17% smaller on average than the manual segmentation. All additively manufactured implants, based on the semi-automated segmentation method could be implanted successfully in a pressure-tight fit into the RWN. The implants based on the manual segmentations failed to fit into the RWN and this suggests that the larger manual segmentations were over-segmentations. This study presents a semi-automated approach for segmenting the RWN and RWM in temporal bone CBCT scans that is efficient, fast, accurate, and not dependent on trained users. In addition, the manual segmentation, often positioned as the gold-standard, actually failed to pass the implantation validation.

Radiological presence of vascular loops in the cerebellopontine angle region in patients with unilateral Ménière's disease

OBJECTIVE

The relationship between vascular compression of the vestibulocochlear nerve and audio-vestibular symptoms remains controversial. We aimed to examine the radiological features of vascular loops signs in cerebellopontine angle (CPA) and internal auditory canal (IAC) in patients with unilateral Ménière's disease (MD).

METHODS

One hundred and thirty-seven patients with unilateral definite MD and 69 control subjects (138 ears) were enrolled. All subjects received magnetic resonance imaging of CPA-IAC. The configuration of vascular loops in CPA-IAC, based on the Kazawa classification system, from MD-affected, non-affected and control ears were compared. The associations between imaging findings and Ménière's stage, electrocochleogram (EcochG) and caloric test were analyzed.

RESULTS

(1) Among the MD-affected ears, 6 cases (4.4%) were classified as Kazawa type IA, 27 cases (19.7%) as IB, 60 cases (43.8%) as IIA, and 44 cases (32.1%) as IIB. No significant interaural difference in the distribution of Kazawa's types was found ([Formula: see text] = 4.737, p = 0.578) in unilateral MD patients. (2) The distribution of Kazawa's types were not significantly different between the MD-affected ears and the control subjects ([Formula: see text] = 2.876, p = 0.411). (3) No relationship was found between Kazawa staging of the MD-affected ear and Ménière's stage (H = 2.679, p = 0.444), EcochG ([Formula: see text] = 0.827, p = 0.867) and caloric test ([Formula: see text] = 4.116, p = 0.248).

CONCLUSIONS

In patients with unilateral MD, the configuration of vascular loops in CPA-IAC region, measured by Kazawa criteria, did not correlate with the laterality, clinical stage, the results of EcochG and caloric test, suggesting that vascular loops may be natural anatomical variations for patients with MD.

Gravity perception disturbance in patients with unilateral Meniere disease

Objective

To investigate gravity perception disturbance (GPD) in patients with Meniere disease (MD), we classified GPD type based on the results of the head-tilt perception gain (HTPG) and the head-upright subjective visual vertical (HU-SVV) evaluated by the head-tilt SVV (HT-SVV) test in patients with unilateral MD.

Methods

We conducted the HT-SVV test on 115 patients with unilateral MD and 115 healthy controls. Among the 115 patients, the period from the first vertigo episode to the examination (PFVE) was known for 91 patients.

Results

The HT-SVV test classified 60.9% and 39.1% of patients with unilateral MD as GPD and non-GPD, respectively. GPD was classified according to HTPG/HU-SVV combinations as follows: Type A GPD (21.7%, normal HTPG/abnormal HU-SVV), Type B GPD (23.5%, abnormal HTPG/normal HU-SVV), and Type C GPD (15.7%, abnormal HTPG/abnormal HU-SVV). As the PFVE became longer, patients with non-GPD and Type A GPD decreased; however, those with Types B and C GPD increased.

Conclusion

This study provides novel information on unilateral MD from the perspective of gravity perception by classifying GPD based on the results of the HT-SVV test. This study's findings suggest that overcompensation for vestibular dysfunction in patients with unilateral MD exhibited by large HTPG abnormalities may be strongly associated with persistent postural-perceptual dizziness.

Level of Evidence

3b.

Longitudinal variation of endolymphatic hydrops in patients with Ménière's disease

Background

The relationships of endolymphatic hydrops (EH) and perilymphatic enhancement (PE) with Ménière's disease (MD) remains unclear. This study aimed to describe the dynamic variation of EH and PE for MD patients over 2 hospitalizations by applying magnetic resonance imaging (MRI) to further clarify the relationships of EH and PE with MD.

Methods

A total of 77 MD patients who underwent inner ear MRI after intravenous administration of gadolinium and pure-tone average (PTA) testing during a first and second hospitalization were included. The degree of EH and PE were evaluated via MRI, and the duration and frequency of vertigo attacks and PTA were collected and recorded. The PTA, EH, and PE for the 2 hospitalizations were compared, and the relationships of EH and cochlear PE with the MD stage were investigated.

Results

There was no difference between the 2 hospitalizations for duration of vertigo attacks or frequency of vertigo attacks. However, there were significant differences in PTA (Z=-3.02, P=0.003). Additionally, the cochlear and vestibular EH in the asymptomatic ear at the second hospitalization was significantly worse than that of the first hospitalization (Z=-2.33 and -2.49, P=0.020 and 0.013, respectively), while there were no differences in EH and PE in the affected ear (all P>0.05). Moreover, the degree of cochlear and vestibular EH was correlated with MD stage (both P<0.01).

Conclusions

Although EH and PE in the affected ear were unchanged over 2 hospitalizations, an underlying EH in the asymptomatic ear and hearing loss in the affected ear for MD patients developed longitudinally with the duration of disease, and EH varied with the natural course of MD whereas PE did not. Therefore, EH instead of PE is necessary but insufficient to cause the clinical symptoms of MD.

Confrontation of endolymphatic hydrops diagnosis on 3-Tesla MRI to clinical and audiovestibular findings in Meniere's disease

Objective

The aim of this study was to compare different MRI diagnostic criteria for endolymphatic hydrops (EH) and to investigate the relation between audiovestibular and MRI findings in Meniere's disease (MD).

Materials and methods

Prospective cross-sectional cohort study in 2 referral centers included 76 patients with unilateral (n = 62) or bilateral (n = 14) MD. All patients underwent inner ear 3T-MRI 4 h (n = 52) or >24H (n = 24) following audiovestibular tests. T2-CISS and 3D-FLAIR images 4H after gadolinium were obtained. EH diagnosis was based on saccular morphology on coronal views (T2 and 3D-FLAIR), semi quantitative estimation of endolymphatic space enlargement, and saccule utricle ratio inversion (SURI) on 3D-FLAIR axial views.

Results

SURI was the best criterion related to the disease side (43 SURI+ on symptomatic ears, n = 77, vs. 6 SURI+ on asymptomatic ears, n = 53, p < 0.0001, Chi-2). Same-day MRI revealed relation between EH, hearing loss and caloric weakness which could not be detected on delayed MRI: SURI was associated with a higher pure-tone average (43 ± 4.1 dB in SURI+ ears, n = 42 vs. 23 ± 2.6 SURI-, n = 62, p < 0.0001, unpaired t-test,), and a higher proportion of vestibular caloric weakness (23/46 SURI+ ears vs. 4/62 SURI-, p < 0.001, Chi-2). Among all criteria, SURI combined to caloric weakness was the best predictor of the affected side in a logistic regression model.

Conclusion

SURI had the strongest relation to the side the disease and audio vestibular findings for unilateral, probable and definite meniere disease. A short delay between MRI and audio vestibular tests improved the coherence between the findings.

2D Measurements of the Angle of the Vestibular Aqueduct Using CT Imaging

Recently, Bächinger et al. developed a software that measures the angle between the vestibular aqueduct proximal to the vestibule and the distal vestibular aqueduct on computed tomography (CT) scans and found differences in the vestibular aqueduct angle between the hypoplastic and degenerative categories of Meniere’s disease (MD). Hypoplastic radiological findings were associated with the development of bilateral MD and hypoplastic changes were not found outside of fetal temporal bones and individuals with MD. The purpose of this study is to examine how the software developed by Bächinger et al. performs when applied to a large dataset of adult patients with varied otologic diagnoses. Adult patients who underwent high resolution flat panel CT scans without intravenous contrast (n = 301) were retrospectively reviewed. Measurements of the angle of the vestibular aqueduct were made using the previously developed software tool. The tool could be applied to measure the vestibular aqueduct angle in most CT scans of the temporal bones (n = 572 ears, 95%). While the majority of ears fell within the normal range of <120 degrees (n = 462, 80%), fourteen ears (2.3%) in 13 patients were found to have vestibular aqueduct angles that meet criteria for hypoplastic MD (>140 degrees). Only one of the 13 patients had a diagnosis of MD and not in the ear in the hypoplastic category. An inconsistent pattern of other otologic diagnoses were found among the 13 individuals meeting criteria for hypoplastic MD. Although prior reports indicate the software has prognostic value in individuals with MD, these results suggest that the software may have lower positive predictive value when applied to a large population of individuals with varied otologic diagnoses.

Association between Osteoporosis and Meniere's Disease: Two Longitudinal Follow-Up Cohort Studies

A high rate of Meniere's disease (MD) in patients with osteoporosis has been suggested. This research intended to estimate the bidirectional association of MD with osteoporosis. The ≥40-year-old population in the Korean National Health Insurance Service-Health Screening Cohort 2002-2019 was examined. In study I, 9529 patients with MD and 38,116 control I participants were analyzed for a previous history of osteoporosis. In study II, 65,858 patients with osteoporosis and 65,858 control II participants were analyzed for a previous history of MD. Stratified Cox proportional hazard models were applied to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of MD for osteoporosis in study I and of osteoporosis for MD in study II. The rate of a prior history of osteoporosis was 13.3% for the MD group and 11.3% for the control I group. The patients with MD had a 1.12 times higher HR for previous osteoporosis (95% CI = 1.04-1.20). In study II, the rate or a prior history of MD was 3.7% for patients with osteoporosis and 2.0% for the control II group. The patients with osteoporosis had a 1.50 times higher HR for previous MD (95% CI = 1.40-1.61). Most subgroups according to age, sex, and comorbid conditions demonstrated consistent bidirectional associations between MD and osteoporosis. Adult patients with MD had a greater risk of osteoporosis. In addition, adult patients with osteoporosis also showed a higher risk of MD.

Is there progression of endolymphatic hydrops in Ménière’s disease? Longitudinal magnetic resonance study

BACKGROUND

Endolymphatic hydrops (EH) is universal in Ménière´s disease (MD). Given its chronic course, with variable interval before complete clinical picture is installed, it seems relevant to understand the progression of vestibular EH and hemato-perilymphatic barrier disruption in patients with MD and monosymptomatic presentations.

METHODS

239 consecutive patients were referred to us with suspected hydropic ear disease. 50 individuals accepted to participate in this study-final longitudinal sample included 24 patients (7 D1, 7 D2, 10 D3). Control group included ten patients. At recruitment, a clinical and MRI re-evaluation was done (3T, intravenous technique) (MR2) and 2 years after MRI was repeated (MR3). Previous MRI (MRI1) were retrospectively evaluated. Patients were classified as definite (D1), possible (D2) and atypical (D3-monosymptomatic) MD. Control group included non-typical symptoms (C2/C3) and 6 asymptomatic (C1). Vestibular endolymphatic ratio (vER) and grading, presence/absence of cochlear EH, asymmetry of cochlear perilymphatic enhancement, and rate of progression of vER were assessed by two independent neuroradiologists and compared between patient and control groups (index ear).

RESULTS

EH was universal and pronounced in D1 and remained stable. vER progression was more variable and higher in some D3 patients (index ear worse) and in D2 (non-index), although this observation was not statistically significant.

CONCLUSIONS

Considering that many probable and monosymptomatic presentations progress years later into definite MD and given the bilateral tendency of the disease, these findings may indicate that there is an initial accelerated worsening of EH in initial stages of the disease. These data should be confirmed with controlled and larger sample studies.

Potential Usefulness of Tracking Head Movement via a Wearable Device for Equilibrium Function Testing at Home

Many studies have reported the use of wearable devices to acquire biological data for the diagnosis and treatment of various diseases. Balance dysfunction, however, is difficult to evaluate in real time because the equilibrium function is conventionally examined using a stabilometer installed on the ground. Here, we used a wearable accelerometer that measures head motion to evaluate balance and examined whether it performs comparably to a conventional stabilometer. We constructed a simplified physical head-feet model that simultaneously records “head” motion measured using an attached wearable accelerometer and center-of-gravity motion at the “feet”, which is measured using an attached stabilometer. Total trajectory length (r = 0.818, p -false discovery rate [FDR] = 0.004) and outer peripheral area (r = 0.691, p -FDR = 0.026) values measured using the wearable device and stabilometer were significantly positively correlated. Root mean square area values were not significantly correlated with wearable device stabilometry but were comparable. These results indicate that wearable, widely available, non-medical devices may be used to assess balance outside the hospital setting, and new approaches for testing balance function should be considered.

Microstructural changes of the vestibulocochlear nerve in patients with Ménière's disease using diffusion tensor imaging

Objective

To evaluate the microstructural changes of the vestibulocochlear nerve in patients with Ménière's disease.

Methods

A total of 26 subjects, 13 patients with MD and 13 healthy controls, underwent diffusion tensor imaging (DTI) on a 3T scanner. The independent sample t-test was used to compare the differences in fractional anisotropy (FA) and apparent diffusion coefficient (ADC) between the two groups. A Pearson correlation was used between DTI and the dizziness handicap inventory (DHI) scores.

Results

There was a significant decrease in FA and an increase in ADC of the vestibulocochlear nerve in MD patients compared with healthy controls (P = 0.04, P = 0.001). FA had negative correlations with the DHI score (r = −0.62, P = 0.02) and DHI-functional score (r = −0.64, P = 0.02).

Conclusion

These results are the first evidence of possible changes in the microstructure of the vestibulocochlear nerves in patients with MD. DTI is a potential technique for evaluating the vestibulocochlear nerve in patients with MD.

Progression of endolymphatic hydrops and vertigo during treatment in Meniere's disease

BACKGROUND

Patients with Meniere's disease (MD) receive treatment to reduce vertigo.

PURPOSE

To explore the fluctuation of vertigo symptoms and the changes in endolymphatic hydrops (EHs) in MD patients during long-term regular medication.

MATERIALS AND METHODS

We enrolled MD patients who had received two magnetic resonance imaging with intravenous contrast agents.

RESULTS

Of the 42 patients in the study, 18(42.9%) had progressive EHs and 3(7.1%) had remission. The change value of the signal intensity ratio (SIR; cochlear perilymph/cerebellum) on the affected side (1.2) was larger than that on the healthy side (0.9), but there was no statistical difference. Among the 30 patients followed up, two patients had complete control of vertigo, two patients had substantial control, and three patients had worse control. The other 23 patients had insignificant control of vertigo symptoms before and after treatment. The correlation between the progression of cochlear and vestibular hydrops and the improvement of vertigo symptoms in MD patients was not significant.

CONCLUSIONS AND SIGNIFICANCE

In treated patients with MD, EHs may progress or relieve over the long course of the disease. But there was no correlation between the development of EHs and changes in vertigo symptoms.