Intratympanic corticosteroids in Ménière's disease: A mini-review

Precision medicine: a new era for inner ear diseases

The inner ear is the organ responsible for hearing and balance. Inner ear dysfunction can be the result of infection, trauma, ototoxic drugs, genetic mutation or predisposition. Often, like for Ménière disease, the cause is unknown. Due to the complex access to the inner ear as a fluid-filled cavity within the temporal bone of the skull, effective diagnosis of inner ear pathologies and targeted drug delivery pose significant challenges. Samples of inner ear fluids can only be collected during surgery because the available procedures damage the tiny and fragile structures of the inner ear. Concerning drug administration, the final dose, kinetics, and targets cannot be controlled. Overcoming these limitations is crucial for successful inner ear precision medicine. Recently, notable advancements in microneedle technologies offer the potential for safe sampling of inner ear fluids and local treatment. Ultrasharp microneedles can reach the inner ear fluids with minimal damage to the organ, collect μl amounts of perilymph, and deliver therapeutic agents in loco. This review highlights the potential of ultrasharp microneedles, combined with nano vectors and gene therapy, to effectively treat inner ear diseases of different etiology on an individual basis. Though further research is necessary to translate these innovative approaches into clinical practice, these technologies may represent a true breakthrough in the clinical approach to inner ear diseases, ushering in a new era of personalized medicine.

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.

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.

In silico pharmacological study of AQP2 inhibition by steroids contextualized to Ménière's disease treatments

Ménière's disease (MD) is characterized by an abnormal dilatation of the endolymphatic compartment called endolymphatic hydrops and is associated with fluctuating hearing losses and vertigo. Corticosteroid treatment is typically administered for its anti-inflammatory effects to MD patients. However, we recently described for the first time a direct interaction of two corticosteroids (dexamethasone and cortisol) with human AQP2 which strongly inhibited water fluxes. From these initial studies, we proposed an AQPs Corticosteroids Binding Site (ACBS). In the present work, we tested the interaction of 10 molecules associated to the steroid family for this putative ACBS. We observed a wide diversity of affinity and inhibitory potential of these molecules toward AQP2 and discussed the implications for inner ear physiology. Among the tested compounds, cholecalciferol, calcitriol and oestradiol were the most efficient AQP2 water permeability inhibitors.

Intratympanic dexamethasone in Manières disease and symptom control

BACKGROUND

Manières disease (MD) is a chronic inner ear disease characterized by recurrent vertigo and fluctuation in auditory symptoms. Vertigo spells have a sudden onset and are difficult for patients to handle. Therefore, treating a patient with MD is still a challenge for clinicians.

AIMS

This study aims to analyse the short-term effects of intratympanic dexamethasone (ITD) on the various symptoms of unilateral MD.

MATERIALS AND METHODS

The study comprised 27 patients with unilateral MD and severe vertigo who failed medication therapy. Treatment was with ITD as an alternative to destructive therapy. Treatment is evaluated after four months.

RESULTS

Significant improvements were measured with Dizziness Handicap Inventory (DHI), Tinnitus Handicap Inventory (THI), frequency of vertigo attacks longer than 20 min, Functional Level Scale (FLS), and tinnitus sensation measured by the Analog Visual Scale (AVS). Patients with severe symptoms grading with DHI and THI experienced the most improvement. Patients have achieved substantial vertigo control in 73%.

CONCLUSION

ITD application shows improvement in controlling vertigo and tinnitus in patients under exacerbation in MD.

SIGNIFICANCE

It is a promising non-destructive addition to the 'stepwise treatment concept' in MD and can be used as a first-line treatment in vertigo control.

Intratympanic corticosteroids for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. Corticosteroids are sometimes administered directly into the middle ear to treat this condition (through the tympanic membrane). The underlying cause of Ménière's disease is unknown, as is the way in which this treatment may work. The efficacy of this intervention in preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

To evaluate the benefits and harms of intratympanic corticosteroids versus placebo or no treatment in people with Ménière's disease.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 September 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs in adults with a diagnosis of Ménière's disease comparing intratympanic corticosteroids with either placebo or no treatment. We excluded studies with follow-up of less than three months, or with a cross-over design (unless data from the first phase of the study could be identified).  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were: 1) improvement in vertigo (assessed as a dichotomous outcome - improved or not improved), 2) change in vertigo (assessed as a continuous outcome, with a score on a numerical scale) and 3) serious adverse events. Our secondary outcomes were: 4) disease-specific health-related quality of life, 5) change in hearing, 6) change in tinnitus and 7) other adverse effects (including tympanic membrane perforation). We considered outcomes reported at three time points: 3 to < 6 months, 6 to ≤ 12 months and > 12 months. We used GRADE to assess the certainty of evidence for each outcome.  MAIN RESULTS: We included 10 studies with a total of 952 participants. All studies used the corticosteroid dexamethasone, with doses ranging from approximately 2 mg to 12 mg.  Improvement in vertigo Intratympanic corticosteroids may make little or no difference to the number of people who report an improvement in their vertigo at 6 to ≤ 12 months follow-up (intratympanic corticosteroids 96.8%, placebo 96.6%, risk ratio (RR) 1.00, 95% confidence interval (CI) 0.92 to 1.10; 2 studies; 60 participants; low-certainty evidence) or at more than 12 months follow-up (intratympanic corticosteroids 100%, placebo 96.3%; RR 1.03, 95% CI 0.87 to 1.23; 2 studies; 58 participants; low-certainty evidence). However, we note the large improvement in the placebo group for these trials, which causes challenges in interpreting these results.  Change in vertigo Assessed with a global score One study (44 participants) assessed the change in vertigo at 3 to < 6 months using a global score, which considered the frequency, duration and severity of vertigo. This is a single, small study and the certainty of the evidence was very low. We are unable to draw meaningful conclusions from the numerical results. Assessed by frequency of vertigo Three studies (304 participants) assessed the change in frequency of vertigo episodes at 3 to < 6 months. Intratympanic corticosteroids may slightly reduce the frequency of vertigo episodes. The proportion of days affected by vertigo was 0.05 lower (absolute difference -5%) in those receiving intratympanic corticosteroids (95% CI -0.07 to -0.02; 3 studies; 472 participants; low-certainty evidence). This is equivalent to a difference of approximately 1.5 days fewer per month affected by vertigo in the corticosteroid group (with the control group having vertigo on approximately 2.5 to 3.5 days per month at the end of follow-up, and those receiving corticosteroids having vertigo on approximately 1 to 2 days per month). However, this result should be interpreted with caution - we are aware of unpublished data at this time point in which corticosteroids failed to show a benefit over placebo. One study also assessed the change in frequency of vertigo at 6 to ≤ 12 months and > 12 months follow-up. However, this is a single, small study and the certainty of the evidence was very low. Therefore, we are unable to draw meaningful conclusions from the numerical results. Serious adverse events Four studies reported this outcome. There may be little or no effect on the occurrence of serious adverse events with intratympanic corticosteroids, but the evidence is very uncertain (intratympanic corticosteroids 3.0%, placebo 4.4%; RR 0.64, 95% CI 0.22 to 1.85; 4 studies; 500 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The evidence for intratympanic corticosteroids in the treatment of Ménière's disease is uncertain. There are relatively few published RCTs, which all consider the same type of corticosteroid (dexamethasone). We also have concerns about publication bias in this area, with the identification of two large RCTs that remain unpublished. The evidence comparing intratympanic corticosteroids to placebo or no treatment is therefore all low- or very low-certainty. This means that we have very low confidence that the effects reported are accurate estimates of the true effect of these interventions. Consensus on the appropriate outcomes to measure in studies of Ménière's disease is needed (i.e. a core outcome set) in order to guide future studies in this area, and enable meta-analysis of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits. Finally, we would also highlight the responsibility that trialists have to ensure results are available, regardless of the outcome of their study.

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.

Prolonged Dexamethasone Exposure Enhances Zebrafish Lateral-Line Regeneration But Disrupts Mitochondrial Homeostasis and Hair Cell Function

The synthetic glucocorticoid dexamethasone is commonly used to treat inner ear disorders. Previous work in larval zebrafish has shown that dexamethasone treatment enhances hair cell regeneration, yet dexamethasone has also been shown to inhibit regeneration of peripheral nerves after lesion. We therefore used the zebrafish model to determine the impact of dexamethasone treatment on lateral-line hair cells and primary afferents. To explore dexamethasone in the context of regeneration, we used copper sulfate (CuSO4) to induce hair cell loss and retraction of nerve terminals, and then allowed animals to recover in dexamethasone for 48 h. Consistent with previous work, we observed significantly more regenerated hair cells in dexamethasone-treated larvae. Importantly, we found that the afferent processes beneath neuromasts also regenerated in the presence of dexamethasone and formed an appropriate number of synapses, indicating that innervation of hair cells was not inhibited by dexamethasone. In addition to regeneration, we also explored the effects of prolonged dexamethasone exposure on lateral-line homeostasis and function. Following dexamethasone treatment, we observed hyperpolarized mitochondrial membrane potentials (ΔΨm) in neuromast hair cells and supporting cells. Hair cells exposed to dexamethasone were also more vulnerable to neomycin-induced cell death. In response to a fluid-jet delivered saturating stimulus, calcium influx through hair cell mechanotransduction channels was significantly reduced, yet presynaptic calcium influx was unchanged. Cumulatively, these observations indicate that dexamethasone enhances hair cell regeneration in lateral-line neuromasts, yet also disrupts mitochondrial homeostasis, making hair cells more vulnerable to ototoxic insults and possibly impacting hair cell function.

Repurposable Drugs That Interact with Steroid Responsive Gene Targets for Inner Ear Disease

Corticosteroids, oral or transtympanic, remain the mainstay for inner ear diseases characterized by hearing fluctuation or sudden changes in hearing, including sudden sensorineural hearing loss (SSNHL), Meniere's disease (MD), and autoimmune inner ear disease (AIED). Despite their use across these diseases, the rate of complete recovery remains low, and results across the literature demonstrates significant heterogeneity with respect to the effect of corticosteroids, suggesting a need to identify more efficacious treatment options. Previously, our group has cross-referenced steroid-responsive genes in the cochlea with published single-cell and single-nucleus transcriptome datasets to demonstrate that steroid-responsive differentially regulated genes are expressed in spiral ganglion neurons (SGN) and stria vascularis (SV) cell types. These differentially regulated genes represent potential druggable gene targets. We utilized multiple gene target databases (DrugBank, Pharos, and LINCS) to identify orally administered, FDA approved medications that potentially target these genes. We identified 42 candidate drugs that have been shown to interact with these genes, with an emphasis on safety profile, and tolerability. This study utilizes multiple databases to identify drugs that can target a number of druggable genes in otologic disorders that are commonly treated with steroids, providing a basis for establishing novel repurposing treatment trials.

Quality of life after intratympanic steroid injection for Ménière's disease

Objective

Methods

Results

Conclusion

Level of evidence

A Perspective for Ménière’s Disease: In Silico Investigations of Dexamethasone as a Direct Modulator of AQP2

Ménière’s disease is a chronic illness characterized by intermittent episodes of vertigo associated with fluctuating sensorineural hearing loss, tinnitus and aural pressure. This pathology strongly correlates with a dilatation of the fluid compartment of the endolymph, so-called hydrops. Dexamethasone is one of the therapeutic approaches recommended when conventional antivertigo treatments have failed. Several mechanisms of actions have been hypothesized for the mode of action of dexamethasone, such as the anti-inflammatory effect or as a regulator of inner ear water homeostasis. However, none of them have been experimentally confirmed so far. Aquaporins (AQPs) are transmembrane water channels and are hence central in the regulation of transcellular water fluxes. In the present study, we investigated the hypothesis that dexamethasone could impact water fluxes in the inner ear by targeting AQP2. We addressed this question through molecular dynamics simulations approaches and managed to demonstrate a direct interaction between AQP2 and dexamethasone and its significant impact on the channel water permeability. Through compartmentalization of sodium and potassium ions, a significant effect of Na+ upon AQP2 water permeability was highlighted as well. The molecular mechanisms involved in dexamethasone binding and in its regulatory action upon AQP2 function are described.

Hearing Function, Degeneration, and Disease: Spotlight on the Stria Vascularis

The stria vascularis (SV) is a highly vascularized tissue lining the lateral wall of the cochlea. The SV maintains cochlear fluid homeostasis, generating the endocochlear potential that is required for sound transduction. In addition, the SV acts as an important blood-labyrinth barrier, tightly regulating the passage of molecules from the blood into the cochlea. A healthy SV is therefore vital for hearing function. Degeneration of the SV is a leading cause of age-related hearing loss, and has been associated with several hearing disorders, including Norrie disease, Meniere's disease, Alport syndrome, Waardenburg syndrome, and Cytomegalovirus-induced hearing loss. Despite the SV's important role in hearing, there is still much that remains to be discovered, including cell-specific function within the SV, mechanisms of SV degeneration, and potential protective or regenerative therapies. In this review, we discuss recent discoveries elucidating the molecular regulatory networks of SV function, mechanisms underlying degeneration of the SV, and otoprotective strategies for preventing drug-induced SV damage. We also highlight recent clinical developments for treating SV-related hearing loss and discuss future research trajectories in the field.

Effects of intratympanic gentamicin and intratympanic glucocorticoids in Ménière's disease: a network meta-analysis

OBJECTIVE

Intratympanic therapies, usually including glucocorticoid and gentamicin, are becoming worldwide used in clinical practice of Ménière's disease today. However, clinical efficacy and safety of these two therapies are still in controversial.

DATA SOURCES

Electronic searches in PubMed, CENTRAL, Web of Science, EMBASE, CINAHL, ClinicalTrials.gov and the European Union Clinical Trials Register were conducted from inception until September 2020.

REVIEW METHODS

The pre-specified protocol of this systematic review and meta-analysis has been registered and published in November 2018 (PROSPERO Identifier: CRD42018114389). All randomized controlled trials of intratympanic gentamicin or glucocorticoids for Ménière's disease, compared with each other or placebo, were considered for this review.

RESULTS

Ten studies with 455 patients met the inclusion criteria. Pooled results indicated significant advantage of intratympanic gentamicin and glucocorticoids over placebo treatments in vertigo control (gentamicin vs placebo: risk rate, RR, 2.56; 95% CI 1.18-5.54; glucocorticoids vs placebo: RR, 3.02; 95% CI 1.36-6.73). There was no significant difference between gentamicin and glucocorticoids in vertigo control (gentamicin vs placebo: RR, 1.18; 95% CI 0.97-1.45). Intratympanic glucocorticoids showed better hearing protective results than gentamicin (change of pure tone audiometric, PTA, mean difference, MD, - 6.48 dB; 95% CI - 11.84 to - 1.13 dB; change of speech discrimination scale, SDS, MD 7.69%; 95% CI 0.83-14.55%).

CONCLUSIONS

Intratympanic gentamicin and glucocorticoids are two effective approaches to control vertigo symptoms for Ménière's disease. Glucocorticoids showed a potentially better hearing protective role over gentamicin.

Evaluating the Efficacy of Intratympanic Dexamethasone in Protecting Against Irreversible Hearing Loss in Patients on Cisplatin-Based Cancer Treatment: A Randomized Controlled Phase IIIB Clinical Trial

OBJECTIVE

To determine the efficacy of long-term high-dose intratympanic dexamethasone in protecting the hearing capacity of cancer patients undergoing cisplatin-based ototoxic treatment.

DESIGN

A randomized controlled phase IIIB clinical trial to evaluate the efficacy of dexamethasone in protecting against hearing loss in patients undergoing cisplatin treatment. The subjects participating in the clinical trial were patients with a neoplastic disease whose treatment protocol included cisplatin. The average dose of cisplatin was 444.87 mg (SD 235.2 mg). Treatment consisted of intratympanically administering dexamethasone via a passive diffusion device called Microwick (8 mg/24 h dose) from the start of treatment with cisplatin to 3 weeks after the last cycle. Patients were administered the medication to one ear, and the contralateral ear was used as the control. The treated ears were randomly chosen using a computer system (randomization). The hearing threshold was evaluated using pure tone audiometry before each cisplatin cycle.

RESULTS

Thirty-four patients were recruited over a 2-year period at a reference tertiary hospital, of whom 11 were excluded. Forty-six ears were analyzed (23 treated and 23 control ears). When treatment was completed, the audiometric analysis showed a higher hearing threshold in the study group than in the control group. Differences were statistically significant at frequencies of 500, 1000, and 6000 Hz: 4.9 dB (1.1 to 8.7), 5.5 dB (0.8 to 10.3), and 16 dB (3.2 to 28.7), respectively, (p < 0.05, 95% confidence interval), but were not clinically significant according to the ASHA hearing loss criteria. Both 8.69% infection complications during treatment and 34.8% permanent perforation at 6 mo were detected after device removal.

CONCLUSIONS

Long-term high-dose intratympanic dexamethasone treatment did not prevent cisplatin-induced hearing loss.

Outcomes of transtympanic dexamethasone perfusion using the MicroWickTM in patients with Ménière's disease: A cross-sectional study

PURPOSE

To assess the efficacy of a 4-week transtympanic dexamethasone perfusion using the Silverstein MicroWick^TM in patients with Ménière's disease.

MATERIALS AND METHODS

A self-reported questionnaire was designed and sent to patients who underwent transtympanic dexamethasone perfusion using the Silverstein MicroWick^TM from January 2017 to December 2020. A retrospective chart review was conducted to gather demographic and audiological data of those who responded.

RESULTS

Forty respondents were separated into Group 1 (n = 34), who required no further procedure, and Group 2 (n = 6), who required additional procedure for Ménière's disease. In Group 1, 50% reported subjective improvement in tinnitus, 59% in aural fullness, 79% in vertigo, and 21% in hearing loss after the MicroWick^TM treatment. A statistical analysis of the scores revealed that the improvement in aural fullness and vertigo met significance (p = 0.03 and p = 0.002, respectively). In Group 2, no significant change was seen in their symptoms. Audiological data showed no significant change in the pure tone average or the word recognition score after the treatment.

CONCLUSION

Transtympanic dexamethasone perfusion using the Silverstein MicroWick^TM is a well-tolerated treatment option for patients with Ménière's disease. Our survey data suggest its significant efficacy in reducing aural fullness and vertigo attacks in these patients. Prospective studies will be conducted to further establish its potential role in successfully managing patients with Ménière's disease.

Pharmacological, surgical and diagnostic innovations in Meniere's disease: a review

Meniere's disease is an inner ear disorder characterized by the presence of endolymphatic hydrops in the inner ear and symptomatology of recurrent and debilitating vertigo attacks, tinnitus, aural fullness, and fluctuating sensorineural hearing loss. Although many therapeutic options for MD have been proposed during years, no consensus has been reached by the scientific community. In the last decade, many therapeutic options have been proposed, as intratympanic steroid, intratympanic gentamicin, and intravenous glycerol. Recently, the role of the antisecretory factor in the diet of MD patients have been investigated. Surgery is recommended for intractable MD; some authors proposed new approaches including transcanal endoscopic infracochlear vestibular neurectomy, new marsupiliazation technique in sac surgery, and tenotomy of the stapedius and tensor tympani muscles.

Clinical management of Menière's disease: Clinician perspective in 2020

Menière's disease (MD) still presents both diagnostic and therapeutic difficulties. Today, this pathology is diagnosed only on clinical criteria. The development of high resolution magnetic resonance imaging of the inner is very promising to improve diagnostic criteria in MD. MD treatment depending on the practitioner and the clinical center, is mainly based on conservative therapies, and if this fails, non-ablative or ablative therapies. MD therefore always exposes clinicians to diagnostic uncertainties, but also to therapeutic difficulties which still lead to destructive treatments, in the absence of targeted, curative treatments, acting on the cause and not on the consequence of the pathology.

Current Insights into Treating Vertigo in Older Adults

The number of older people has been increasing over recent decades in Western populations. Dizziness, imbalance, and vertigo constitute some of the most common complaints in older patients, and risk of falling is the most frequent and worrying consequence. It has been reported that 15–20% of the adult population experiences these debilitating symptoms. Among the diseases that may be associated with vertigo, the three classes of otological, central, and functional (psychological) dizziness may be distinguished. Overall, vestibular disorders account for 48% of vertiginous complaints in the older population. The main focus of this article is to review the forms of pharmacotherapy for vertigo, especially with regard to older patients, who may be treated simultaneously with other drugs for different comorbidities. Interactions with other drugs should be considered in the choice of a particular course of treatment. Moreover, overuse of pharmacotherapy for the management of vertigo in the elderly may prevent the development of the central compensatory mechanism that sustains both static and dynamic imbalance after a vertiginous crisis. In the majority of patients, vestibular and physical rehabilitation are strongly advised and rarely contraindicated.

Determination of the Round Window Niche Anatomy Using Cone Beam Computed Tomography Imaging as Preparatory Work for Individualized Drug-Releasing Implants

Modern therapy of inner ear disorders is increasingly shifting to local drug delivery using a growing number of pharmaceuticals. Access to the inner ear is usually made via the round window membrane (RWM), located in the bony round window niche (RWN). We hypothesize that the individual shape and size of the RWN have to be taken into account for safe reliable and controlled drug delivery. Therefore, we investigated the anatomy and its variations. Cone beam computed tomography (CBCT) images of 50 patients were analyzed. Based on the reconstructed 3D volumes, individual anatomies of the RWN, RWM, and bony overhang were determined by segmentation using 3D Slicer^TM with a custom build plug-in. A large individual anatomical variability of the RWN with a mean volume of 4.54 mm³ (min 2.28 mm³, max 6.64 mm³) was measured. The area of the RWM ranged from 1.30 to 4.39 mm² (mean: 2.93 mm²). The bony overhang had a mean length of 0.56 mm (min 0.04 mm, max 1.24 mm) and the shape was individually very different. Our data suggest that there is a potential for individually designed and additively manufactured RWN implants due to large differences in the volume and shape of the RWN.

Steroid Nomenclature in Inner Ear Therapy

: Local glucocorticosteroid ("steroid") therapy is widely used to treat the inner ears of patients with Menière's disease, idiopathic sudden sensorineural hearing loss and in combination with cochlear implants. Applied steroids have included dexamethasone, methylprednisolone, and triamcinolone. In reality, however, this is often not true and the steroid forms commonly applied are dexamethasone-phosphate, methylprednisolone-hemisuccinate, or triamcinolone-acetonide. In each case, the additional component is not a counter-ion but is covalently bound to the molecule to increase aqueous solubility or potency. These drug forms are approved for intravenous or intramuscular delivery and are used "off-label" in the ear. When given systemically, the molecular form of the drug is of minor importance as the drugs are rapidly metabolized. In contrast, when administered intratympanically, the exact form of the drug has a major influence on entry into perilymph and elimination from perilymph, which in turn influences distribution along the cochlear scalae. Dexamethasone-phosphate has completely different molecular properties to dexamethasone and has different pharmacokinetic properties entering and leaving perilymph. Molecular properties and perilymph pharmacokinetics also differ markedly for triamcinolone and triamcinolone-acetonide. Methylprednisolone-hemisuccinate has completely different molecular properties to methylprednisolone. In the ear, different steroid forms cannot therefore be regarded as equivalent in terms of pharmacokinetics or efficacy. This presents a terminology problem, where in many cases the drug stated in publications may not be the form actually administered. The lack of precision in nomenclature is a serious problem for the inner ear drug delivery field and needs to be recognized.

Use of Super Paramagnetic Iron Oxide Nanoparticles as Drug Carriers in Brain and Ear: State of the Art and Challenges

Drug delivery and distribution in the central nervous system (CNS) and the inner ear represent a challenge for the medical and scientific world, especially because of the blood-brain and the blood-perilymph barriers. Solutions are being studied to circumvent or to facilitate drug diffusion across these structures. Using superparamagnetic iron oxide nanoparticles (SPIONs), which can be coated to change their properties and ensure biocompatibility, represents a promising tool as a drug carrier. They can act as nanocarriers and can be driven with precision by magnetic forces. The aim of this study was to systematically review the use of SPIONs in the CNS and the inner ear. A systematic PubMed search between 1999 and 2019 yielded 97 studies. In this review, we describe the applications of the SPIONS, their design, their administration, their pharmacokinetic, their toxicity and the methods used for targeted delivery of drugs into the ear and the CNS.

Cochlear protein biomarkers as potential sites for targeted inner ear drug delivery

The delivery of therapies to the cochlea is notoriously challenging. It is an organ protected by a number of barriers that need to be overcome in the drug delivery process. Additionally, there are multiple sites of possible damage within the cochlea. Despite the many potential sites of damage, acquired otologic insults preferentially damage a single location. While progress has been made in techniques for inner ear drug delivery, the current techniques remain non-specific and our ability to deliver therapies in a cell-specific manner are limited. Fortunately, there are proteins specific to various cell-types within the cochlea (e.g., hair cells, spiral ganglion cells, stria vascularis) that function as biomarkers of site-specific damage. These protein biomarkers have potential to serve as targets for cell-specific inner ear drug delivery. In this manuscript, we review the concept of biomarkers and targeted- inner ear drug delivery and the well-characterized protein biomarkers within each of the locations of interest within the cochlea. Our review will focus on targeted drug delivery in the setting of acquired otologic insults (e.g., ototoxicity, noise-induce hearing loss). The goal is not to discuss therapies to treat acquired otologic insults, rather, to establish potential concepts of how to deliver therapies in a targeted, cell-specific manner. Based on our review, it is clear that future of inner ear drug delivery is a discipline filled with potential that will require collaborative efforts among clinicians and scientists to optimize treatment of otologic insults.

Triple Canal Occlusion for the Treatment of Intractable Menière's Disease

OBJECTIVE

Menière's disease can be a debilitating condition but in most cases the symptoms are controlled by lifestyle changes and medical management. However, some patients remain symptomatic despite medical treatment and have the option of more invasive surgical treatments. Surgical intervention for Menière's includes a range of interventions from grommet insertion, intratympanic steroids/Gentamicin, endolymphatic sac decompression, labyrinthectomy, and vestibular neurectomy. A recently described technique involves the occlusion of all three semi-circular canals as an alternative in intractable Menière's disease.

STUDY DESIGN

This is a case series of three patients who underwent triple canal occlusion for the treatment of intractable Menière's disease.

SETTING

Patients were selected from those who were referred to Queen Elizabeth Hospital in Birmingham, a tertiary referral center.

PATIENTS

Patients who were severely symptomatic despite medical treatment who were considering ablative therapy were offered the option of triple canal occlusion as an alternative.

INTERVENTION

We report a series of Menière's patients treated by triple canal occlusion, describe the rationale behind this intervention, the surgical technique, and preliminary results.

MAIN OUTCOME MEASURE

Each patient was followed up for a minimum of 2 years following the procedure. The main outcomes measures were the class of vertigo control and hearing threshold levels according to the American Academy of Otolaryngology-Head and Neck Surgery guidelines.

RESULTS

Of the three patients, two were men and one was woman, the age range was 45 years to 61 years old. Two patients with unilateral disease achieved class A control whereas one patient with bilateral disease achieved class B control. Two patients who underwent the procedure had little or no effect to their hearing on the treated side however one patient suffered a 30 dB hearing loss on the operative side.

CONCLUSIONS

Based on our limited experience and the early reports in the literature we consider that there are potential patient benefits for triple canal occlusion for intractable Menière's disease as an alternative to vestibular neurectomy due to the reduced morbidity and long-term efficacy.

Nanocarriers for drug delivery to the inner ear: Physicochemical key parameters, biodistribution, safety and efficacy

Despite the high incidence of inner ear disorders, there are still no dedicated medications on the market. Drugs are currently administered by the intratympanic route, the safest way to maximize drug concentration in the inner ear. Nevertheless, therapeutic doses are ensured for only a few minutes/hours using drug solutions or suspensions. The passage through the middle ear barrier strongly depends on drug physicochemical characteristics. For the past 15 years, drug encapsulation into nanocarriers has been developed to overcome this drawback. Nanocarriers are well known to sustain drug release and protect it from degradation. In this review, in vivo studies are detailed concerning nanocarrier biodistribution, their pathway mechanisms in the inner ear and the resulting drug pharmacokinetics. Key parameters influencing nanocarrier biodistribution are identified and discussed: nanocarrier size, concentration, surface composition and shape. Recent advanced strategies that combine nanocarriers with hydrogels, specific tissue targeting or modification of the round window permeability (cell-penetrating peptide, magnetic delivery) are explored. Most of the nanocarriers appear to be safe for the inner ear and provide a significant efficacy over classic formulations in animal models. However, many challenges remain to be overcome for future clinical applications.

Pharmacological, Surgical and Diagnostic Innovations in Meniere's Disease: A Review

PURPOSE

To investigate literature about pharmacological, surgical, and diagnostic innovations for Meniere's Disease (MD).

SUMMARY

Meniere's disease is an inner ear disorder characterized by the presence of endolymphatic hydrops in the inner ear and symptomatology of recurrent and debilitating vertigo attacks, tinnitus, aural fullness, and fluctuating sensorineural hearing loss. Although many therapeutic options for MD have been proposed during years, no consensus has been reached by the scientific community. In the last decade, many therapeutic options have been proposed, as intratympanic steroid, intratympanic gentamicin, and intravenous glycerol. Recently, the role of the antisecretory factor in the diet of MD patients have been investigated. Surgery is recommended for intractable MD; some authors proposed new approaches including transcanal endoscopic infracochlear vestibular neurectomy, new marsupiliazation technique in sac surgery, and tenotomy of the stapedius and tensor tympani muscles.

Therapeutic role of intravenous glycerol for Meniere's disease. Preliminary results

PURPOSE

Osmotic diuretics such as glycerol are used for diagnostic purposes in patients with a suspect of Meniere's disease (MD). Scientific evidence in the animal model and in humans has shown that glycerol can induce a reduction in endolymphatic hydrops; however, its use for therapeutic purposes in MD has never been reported. The aim of this study was to evaluate the effectiveness on symptom control of intravenous glycerol in a sample of patients with definite unilateral MD not responsive to dietary restrictions.

MATERIALS AND METHODS

Forty patients with unilateral intractable MD were included in the study. After audio-vestibular evaluation, patients were treated with intravenous 10% glycerol with 0.9% sodium chloride, 0.5 g/kg ml once a day for 2 consecutive days every fifteen days for six months. Vertigo attacks were evaluated before and after therapy and categorized into classes A-F according to the 2015 Equilibrium Committee criteria. Tinnitus and quality of life were evaluated through the Tinnitus Handicap Inventory and the Functionality Level Scale questionnaires.

RESULTS

Before treatment, patients had an average of 3.2 vertigo attacks/month; during the six months after treatment the average number of attacks/month decreased to 1.2 (p < 0.0001). At the end of the study period, 25 patients (62.5%) were in Class B vertigo control; 10 patients (25%) in Class C; and 5 patients (12.5%) in Class D. No patients were in Class A, E and F. No hearing deterioration was found in all treated patients. Quality of life according to administered questionnaires improved after treatment.

CONCLUSIONS

In our sample, intravenous infusion of glycerol for two consecutive days every fifteen days for six months based on the patient's weight improved vertigo attacks and reduced the discomfort generated by tinnitus raising quality of life in patients with unilateral MD unresponsive to dietary restrictions.

Clinical Practice Guideline: Ménière's Disease

OBJECTIVE

Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid (endolymph) volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Conventional imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many and typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies.

PURPOSE

The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

Causes and treatment of idiopathic benign paroxysmal positional vertigo based on endocrinological and other metabolic factors

The genesis of the Benign Paroxysmal Positional Vertigo (BPPV) seems to be related to some metabolic factors. These factors, such as vitamin D, glucocorticoids, and even thyroid and growth hormones, can affect bone metabolism and the mineralization of otoconia. It also seems to link to factors related to aging or nutritional habits. Besides, since the incidence of BPPV is quantitatively higher in women than in men, female sex steroids could be associated with this process. It could be useful to understand how these factors act in otoconial mineralization if we want to develop treatments aimed at preventing or delaying BPPV recurrences. In this review, we will analyze the role of these metabolic and hormonal factors in otoconial mineralization and in the treatment of BPPV.

Intratympanic Steroid for Menière's Disease: A Systematic Review

OBJECTIVES

To investigate the beneficial effects and safety of intratympanic steroid installation compared with placebo in patients with Menière's disease.

METHODS

We performed a systematic literature search in MEDLINE and EMBASE for existing systematic reviews and individual randomized controlled trials (RCTs). Studies were included if they investigated the usage intratympanic steroids in patients aged 18 and above, with definite or probable Menière's disease. The quality of the identified existing reviews was assessed using the AMSTAR tool. The risk of bias in RCTs was assessed using the Cochrane Risk of Bias Tool and overall quality of the individual outcomes was evaluated using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) method.

RESULTS

The literature search provided four systematic reviews, from which one yielded a sufficient AMSTAR evaluation and subsequently provided three RCTs relevant for inclusion. Due to the lack of sufficient reporting of the data, quantitative synthesis was not applicable. In the qualitative synthesis for the primary outcome, the results from the RCTs showed that there was a slight indication of steroid treatment reducing the frequency of vertiginous attacks. No serious adverse events were reported. Based on the GRADE approach the quality for both findings is very low. No studies reported on the secondary outcomes.

CONCLUSION

The effect of intratympanic steroid treatment in Menière's disease is questionable. There is a great need for further research to sufficiently assess whether steroid treatment may be considered as a safe and effective treatment for patients with Menière's disease.

Consensus statement. Corticosteroid therapy in ENT in the context of the COVID-19 pandemic

This consensus statement about the indications and modalities of corticosteroid treatment in the context of the COVID-19 pandemic was jointly written by experts from the French Association of Otology and Oto-Neurology (AFON) and from the French Society of Otorhinolaryngology, Head and Neck Surgery (SFORL). There is currently not enough data in favour of danger or benefit from corticosteroids in COVID-19, so until this matter is resolved it is advisable to limit their indications to the most serious clinical pictures for which it is well established that this type of treatment has a positive impact on the progression of symptoms. In Grade V and VI Bell's palsy according to the House-Brackmann grading system, a week's course of oral corticosteroids is recommended. Corticosteroid therapy is also recommended in cases of sudden hearing loss of more than 60 dB, either in the form of intratympanic injections or a week's course of oral medication. In rhinology, there is no indication for systemic corticosteroid therapy in the current situation. However, patients are advised to continue with their local corticosteroid therapy in the form of a nasal spray or by inhalation. Treatments with corticosteroid nasal sprays can still be prescribed if there is no alternative. Finally, systemic or local corticosteroid therapy is not indicated for bacterial ENT infections.

Dietary Restriction for The Treatment of Meniere's Disease

Meniere's disease (MD) is an idiopathic inner ear disorder characterized by spontaneous recurrent vertigo, fluctuating sensorineural hearing loss (SNHL), aural fullness and tinnitus. Endolymphatic hydrops (EH) of the inner ear is currently considered the pathophysiological mechanisms that underlies typical symptoms of MD. MD diagnosis is based on the criteria of the Baràny Society. There are many therapeutic options for MD, but none is considered effective by the scientific community. The first-line treatment commonly includes dietary modification, as low salt diet and reduction of alcohol and caffeine daily intake. Although some studies showed a positive effect of these dietary restrictions, even in the prevention of recurrences, currently there is no uniform consensus on their usefulness. New dietary approach, such SPC-flakes, are being evaluated: further assessments will be needed to validate their use in clinical practice.

Long-Term Follow-Up of Intratympanic Methylprednisolone Versus Gentamicin in Patients With Unilateral Menière's Disease

OBJECTIVES

To determine whether long term (>48 months) symptomatic vertigo control is sustained in patients with Menière's disease from a previous comparative trial of intratympanic methylprednisolone versus gentamicin, and if the two treatments remain nonsignificantly different at long-term follow-up.

STUDY DESIGN

Mail survey recording vertigo frequency in the previous one and six months, further intratympanic treatment received, and validated symptom questionnaires.

SETTING

Outpatient hospital clinic setting.

PATIENTS

Adult patients with definite unilateral refractory Menière's disease, who previously received intratympanic treatment in a comparative trial.

INTERVENTION

A survey of trial participants who received intratympanic gentamicin (40 mg/mL) or methylprednisolone (62.5 mg/mL).

OUTCOME MEASURES

Primary: number of vertigo attacks in the 6 months prior to receiving this survey compared with the 6 months before the first trial injection. Secondary number of vertigo attacks over the previous 1 month; validated symptom questionnaire scores of tinnitus, dizziness, vertigo, aural fullness, and functional disability.

RESULTS

Forty six of the 60 original trial patients (77%) completed the survey, 24 from the gentamicin and 22 from the methylprednisolone group. Average follow-up was 70.8 months (standard deviation 17.0) from the first treatment injection. Vertigo attacks in the 6 months prior to receiving the current survey reduced by 95% compared to baseline in both drug groups (intention-to-treat analysis, both p < 0.001). No significant difference between drugs was found for the primary and secondary outcomes. Eight participants (methylprednisolone = 5 and gentamicin = 3) required further injections for relapse after completing the original trial.

CONCLUSION

Intratympanic methylprednisolone treatment provides effective long-lasting relief of vertigo, without the known inner-ear toxicity associated with gentamicin. There are no significant differences between the two treatments at long term follow-up.

Evaluation of a Model of Long-Term Middle Ear Catheterization for Repeat Infusion Administration and Cochlear Hair Cell Injury in Guinea Pigs

Middle ear administration has numerous applications, including antibiotherapy and gene therapy, and is increasingly used to target the auditory and vestibular systems. In animal studies, investigating repeated exposure that mimics clinical dosing regimens has remained a challenge due to the lack of suitable models. Intratympanic injections are not suitable for long-term studies due to the increased risk related to tympanic membrane rupture or scarring and repeat anesthesia events. Surgical models of middle ear catheterization previously used have not been reliable for longer than 4 weeks, resulted in elevated stress levels, and have been associated with significant changes related to the surgery and/or the presence of the catheter such as local trauma and inflammatory and degenerative processes. These complications cause decreased hearing/deafness and greatly diminish the value and accuracy of ototoxicity studies. We describe here a procedure that permits repeat dosing into the middle ear of guinea pigs and can be used to produce a model of aminoglycoside-induced hair cell injury. The innocuity of the procedures and the efficacy of the ototoxicity model were confirmed using auditory brain stem response assessment, histopathological evaluation, and cytocochleograms. Procedure-related changes were limited to minimal inflammation in the middle ear.

A comparison of endolymphatic shunt surgery and intratympanic gentamicin for meniere's disease

OBJECTIVE

To report audiovestibular outcomes following endolymphatic shunt surgery (ELS) and intratympanic gentamicin injections (ITG) in patients with Meniere's disease (MD).

STUDY DESIGN

Retrospective matched cohort study METHODS: Patients with MD refractory to medical management between 2004 and 2017 were reviewed: 44 patients underwent ELS and had outcomes available, while 27 patients underwent ITG and had outcomes available. Mean follow-up durations for the ELS and ITG groups were 39.1 and 43.3 months, respectively. Twenty-six patients from the ELS group and 24 patients from the ITG group were then included in a pretreatment hearing- and age-matched analysis. Main outcome measures were successful control of vertigo, pure-tone average (PTA; 0.5, 1, 2 and 4 kHz), word recognition score (WRS), and treatment complications.

RESULTS

A matched analysis showed vertigo control rates of 73.1% in the ELS group and 66.8% in the ITG group, which were not significantly different (P = .760). The change in PTA following treatment was statistically similar between the ELS group (6.2 dB) and ITG group (4.6 dB) (P = .521), while the change in WRS for the ELS group (+3.9 %) was significantly more favorable than the ITG group (-13.6 %) (P = .046). Chronic post-treatment unsteadiness was reported in 25.0% of the ITG group and was not encountered in the ELS group (P = .009).

CONCLUSION

ELS provided successful vertigo control at least as well as ITG with a lower incidence of audiovestibular complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2455-2460, 2020.

Low-dose intratympanic gentamicin administration for unilateral Meniere's disease using a method based on clinical symptomatology: Preliminary results

PURPOSE

There are many therapeutic options for Meniere's disease (MD); intratympanic (IT) gentamicin has been proposed for intractable cases although controversy about dosage and method exists. 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 in which administration was repeated only if vertigo attacks recurred, with a 2-week interval between injections.

MATERIALS AND METHODS

Forty-eight patients with unilateral intractable MD were included in the study. 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 assessment with pure tone audiometry, vestibular bed-side examination and video head impulse test was performed.

RESULTS

Before treatment patients had an average of 4.4 vertigo attacks/month; after treatment the average number decreased to 0.52. The majority of patients (77%) reached Class A vertigo control with 5 or less gentamicin injections. VOR gain was unaffected in the healthy side and significantly reduced in the affected side. No hearing deterioration was found in all treated patients.

CONCLUSIONS

Low-dose IT gentamicin administration based on clinical symptomatology can produce a satisfactory control of vertigo attacks after treatment; such protocol had an effect mainly on the vestibular function as demonstrated by the significant reduction in VOR gain in the affected side avoiding a cochlear damage.

Superparamagnetic Nanoparticle Delivery to the Cochlea Through Round Window by External Magnetic Field: Feasibility and Toxicity

Introduction. The objective of this study was to evaluate the feasibility and toxicity of superparamagnetic iron oxide nanoparticles (SPIONs) administered into the cochlea through the round window (RW) by an external magnetic field. Materials and Methods. In 5 Wistar rats, the left RW was punctured. SPIONs suspended in hyaluronic gel (5 mg/mL) were applied in the RW niche and covered by a muscle graft. The nanoparticles were mobilized using a rare earth magnet (0.54 T) held in 4 consecutive positions around the head. The right ear served as control. Hearing function was monitored by auditory brainstem responses (4-32 kHz tone bursts). Results. The auditory thresholds remained unchanged 1 month after the administration. The histological study of the cochleae showed that SPIONs were driven into the scala tympani in the basal turn, the second turn, and the apex. Conclusion. Superparamagnetic nanoparticles can be driven inside the cochlea toward the apex with a preserved hearing up to 1 month in rats.

Relationship between changes in hearing function and volumes of endolymphatic hydrops after endolymphatic sac drainage

Background: Endolymphatic sac drainage (ELSD) may have a positive effect on endolymphatic hydrops (EH) and may help to preserve inner ear function. However, the relationship between changes in EH volumes and hearing function after ELSD has not been described. Objectives: We aimed to reveal the factors related to changes in hearing and EH following ELSD. Material and Methods: Twenty-one patients who received ELSD were enrolled. Pure tone audiometry and 3-T magnetic resonance imaging (MRI) 4 h after intravenous injection of gadolinium enhancement were performed just before surgery and 2 years later. To characterize the endolymphatic space (ELS), we measured the volume of the total fluid (TFS) and ELS and calculated the ratio of ELS to TFS (ELS ratio). Results: The ELS ratio of the patients who showed hearing improvement was 18.5 ± 11.4% before surgery and 23.9 ± 14.3% after. For those with no change, it was 29.7 ± 10.8% before and 29.4 ± 9.5% after, and in patients with worsened hearing function it was 22.7 ± 7.5% before and 27.2 ± 13.4% after. Conclusion: We found no correlation between the changes in hearing function and the volume of EH after ELSD.

Therapeutic strategies in the treatment of Menière's disease: the Italian experience

PURPOSE

Ménière's disease (MD) is an inner ear disorder of unknown etiology, whose pathological substrate is the endolymphatic hydrops. Different treatments have been proposed; however, evidence of their effectiveness is lacking. The aim of this study was to evaluate by a questionnaire which medical and surgical treatments are used in Italy for the treatment of MD and to compare them with those proposed in other countries.

METHODS

An electronic questionnaire of 40 questions was formulated and sent to Italian otolaryngologist (ENT) divided into two groups: Group 1 ("generalists" 60.8%) and Group 2 ("neurotologist- NO" 39.2%).

RESULTS

One hundred and twenty five ENT replied. Treatment of the acute phase, apart from symptomatics, was based on diuretics that are prescribed by 83.5% of respondents, steroids, prescribed by 66.7%, and vasodilators, prescribed by 22%. In the intercritical phase, 87.2% of respondents recommended low-salt diet, 78.4% of respondents prescribed betahistine, and 52.8% diuretics. Statistical analysis did not show correlation neither with the declared specialization nor with the number of patients treated. In case of failure of medical treatment, IT gentamicin was suggested by 48.8% of the respondents and IT steroids by 40.8%. Statistical analysis showed that generalists prefer IT steroids and NO IT gentamicin (p 0.019). In case of failure of both medical treatment and IT treatment, vestibular neurectomy was indicated by 58.4% of the respondents, 6.4% indicated endolymphatic sac surgery, and 2.4% surgical labyrinthectomy.

CONCLUSION

In Italy, the treatment of MD stand on a gradual approach that starts from the dietary-behavioral changes and a pharmacological therapy based on betahistine. In refractory cases, IT treatment initially with steroids and, therefore, with gentamicin allows the control in vertigo in the majority of cases. In case of failure of IT treatment, VNS is the surgery of choice.

Three-Dimensional Magnetic Resonance Imaging Reveals the Relationship Between the Control of Vertigo and Decreases in Endolymphatic Hydrops After Endolymphatic Sac Drainage With Steroids for Meniere's Disease

Meniere's disease is a common disease, that presents with recurrent vertigo and cochlear symptoms. The pathology of Meniere's disease was first reported to involve endolymphatic hydrops in 1938. The endolymphatic sac is thought to have a role to keep the hydrostatic pressure and endolymph homeostasis for the inner ear. As a surgery for intractable Meniere's disease, endolymphatic sac drainage with intraendolymphatic sac application of large doses of steroids is performed to control the endolymphatic hydrops and preserve or improve inner ear function. In the present study, to observe the effect of this surgery, we calculated the endolymphatic space size using 3-Tesla magnetic resonance imaging (MRI) 4 h after intravenous injection of gadolinium enhancement at two time points: just before surgery and 2 years after. To reveal the condition of the endolymphatic space, we constructed three-dimensional MR images semi-automatically and fused the three-dimensional images of the total fluid space of inner ear and the endolymphatic space. After fusing the images, we calculated the volume of the total fluid space and endolymphatic space. Two years after surgery, 16 of 20 patients (80.0%) showed relief from vertigo/dizziness and reductions in the ratio of the volume of the endolymphatic size to the total fluid space of inner ear. Endolymphatic sac drainage with intraendolymphatic sac application of large doses of steroids could control vertigo/dizziness and decrease the endolymphatic hydrops. These results indicate that endolymphatic sac drainage is a good treatment option for patients with intractable Meniere's disease. In addition, volumetric measurement of inner ear volume could be useful for confirming the effect of treatments on Meniere's disease.