The genetics of Ménière's disease

Intratympanic gentamicin for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. Aminoglycosides are sometimes administered directly into the middle ear to treat this condition. The aim of this treatment is to partially or completely destroy the balance function of the affected ear. 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 aminoglycosides 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Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials.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 aminoglycosides 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. 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 five RCTs with a total of 137 participants. All studies compared the use of gentamicin to either placebo or no treatment. Due to the very small numbers of participants in these trials, and concerns over the conduct and reporting of some studies, we considered all the evidence in this review to be very low-certainty.  Improvement in vertigo This outcome was assessed by only two studies, and they used different time periods for reporting. Improvement in vertigo was reported by more participants who received gentamicin at both 6 to ≤ 12 months (16/16 participants who received gentamicin, compared to 0/16 participants with no intervention; risk ratio (RR) 33.00, 95% confidence interval (CI) 2.15 to 507; 1 study; 32 participants; very low-certainty evidence) and at > 12 months follow-up (12/12 participants receiving gentamicin, compared to 6/10 participants receiving placebo; RR 1.63, 95% CI 0.98 to 2.69; 1 study; 22 participants; very low-certainty evidence). However, we were unable to conduct any meta-analysis for this outcome, the certainty of the evidence was very low and we cannot draw any meaningful conclusions from the results.  Change in vertigo Again, two studies assessed this outcome, but used different methods of measuring vertigo and assessed the outcome at different time points. We were therefore unable to carry out any meta-analysis or draw any meaningful conclusions from the results. Global scores of vertigo were lower for those who received gentamicin at both 6 to ≤ 12 months (mean difference (MD) -1 point, 95% CI -1.68 to -0.32; 1 study; 26 participants; very low-certainty evidence; four-point scale; minimally clinically important difference presumed to be one point) and at > 12 months (MD -1.8 points, 95% CI -2.49 to -1.11; 1 study; 26 participants; very low-certainty evidence). Vertigo frequency was also lower at > 12 months for those who received gentamicin (0 attacks per year in participants receiving gentamicin compared to 11 attacks per year for those receiving placebo; 1 study; 22 participants; very low-certainty evidence).  Serious adverse events None of the included studies provided information on the total number of participants who experienced a serious adverse event. It is unclear whether this is because no adverse events occurred, or because they were not assessed or reported.  AUTHORS' CONCLUSIONS: The evidence for the use of intratympanic gentamicin in the treatment of Ménière's disease is very uncertain. This is primarily due to the fact that there are few published RCTs in this area, and all the studies we identified enrolled a very small number of participants. As the studies assessed different outcomes, using different methods, and reported at different time points, we were not able to pool the results to obtain more reliable estimates of the efficacy of this treatment. More people may report an improvement in vertigo following gentamicin treatment, and scores of vertigo symptoms may also improve. However, the limitations of the evidence mean that we cannot be sure of these effects. Although there is the potential for intratympanic gentamicin to cause harm (for example, hearing loss) we did not find any information about the risks of treatment in this review.  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.

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.

Lifestyle and dietary interventions for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. Lifestyle or dietary modifications (including reducing the amount of salt or caffeine in the diet) are sometimes suggested to be of benefit for this condition. The underlying cause of Ménière's disease is unknown, as is the way in which these interventions may work. The efficacy of these different interventions at preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

To evaluate the benefits and harms of lifestyle and dietary interventions 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 Ménière's disease comparing any lifestyle or dietary intervention 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. 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 two RCTs, one related to diet, and the other related to fluid intake and sleep. In a Swedish study, 51 participants were randomised to receive 'specially processed cereals' or standard cereals. The specially processed cereals are thought to stimulate the production of anti-secretory factor - a protein that reduces inflammation and fluid secretion. Participants received the cereals for three months. The only outcome reported by this study was disease-specific health-related quality of life.  The second study was conducted in Japan. The participants (223) were randomised to receive abundant water intake (35 mL/kg/day), or to sleep in darkness (in an unlit room for six to seven hours per night), or to receive no intervention. The duration of follow-up was two years. The outcomes assessed were 'improvement in vertigo' and hearing.  As these studies considered different interventions we were unable to carry out any meta-analysis, and for almost all outcomes the certainty of the evidence was very low. We are unable to draw meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

The evidence for lifestyle or dietary interventions for Ménière's disease is very uncertain. We did not identify any placebo-controlled RCTs for interventions that are frequently recommended for those with Ménière's disease, such as salt restriction or caffeine restriction. We identified only two RCTs that compared a lifestyle or dietary intervention to placebo or no treatment, and the evidence that is currently available from these studies is of 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-analyses of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits.

Surgical interventions for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. First-line treatments often involve dietary or lifestyle changes, medication or local (intratympanic) treatments. However, surgery may also be considered for people with persistent or severe symptoms. The efficacy of different surgical interventions at preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

To evaluate the benefits and harms of surgical interventions 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 definite or probable Ménière's disease comparing ventilation tubes, endolymphatic sac surgery, semi-circular canal plugging/obliteration, vestibular nerve section or labyrinthectomy with either placebo (sham surgery) 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. 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 two studies with a total of 178 participants. One evaluated ventilation tubes compared to no treatment, the other evaluated endolymphatic sac decompression compared to sham surgery.  Ventilation tubes We included a single RCT of 148 participants with definite Ménière's disease. It was conducted in a single centre in Japan from 2010 to 2013. Participants either received ventilation tubes with standard medical treatment, or standard medical treatment alone, and were followed up for two years. Some data were reported on the number of participants in whom vertigo resolved, and the effect of the intervention on hearing. Our other primary and secondary outcomes were not reported in this study. This is a single, small study and for all outcomes the certainty of evidence was low or very low. We are unable to draw meaningful conclusions from the numerical results. Endolymphatic sac decompression We also included one RCT of 30 participants that compared endolymphatic sac decompression with sham surgery. This was a single-centre study conducted in Denmark during the 1980s. Follow-up was predominantly conducted at one year, but additional follow-up continued for up to nine years in some participants. Some data were reported on hearing and vertigo (both improvement in vertigo and change in vertigo), but our other outcomes of interest were not reported. Again, this is a single, very small study and we rated the certainty of the evidence as very low for all outcomes. We are therefore unable to draw meaningful conclusions from the numerical results.  AUTHORS' CONCLUSIONS: We are unable to draw clear conclusions about the efficacy of these surgical interventions for Ménière's disease. We identified evidence for only two of our five proposed comparisons, and we assessed all the evidence as 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. Many of the outcomes that we planned to assess were not reported by the studies, such as the impact on quality of life, and adverse effects of the 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-analyses of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits.

Systemic pharmacological interventions for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. A number of pharmacological interventions have been used in the management of this condition, including betahistine, diuretics, antiviral medications and corticosteroids. The underlying cause of Ménière's disease is unknown, as is the way in which these treatments may work. The efficacy of these different interventions at preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

To evaluate the benefits and harms of systemic pharmacological interventions 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 definite or probable Ménière's disease comparing betahistine, diuretics, antihistamines, antivirals or systemic 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. 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 848 participants. The studies evaluated the following interventions: betahistine, diuretics, antivirals and corticosteroids. We did not identify any evidence on antihistamines.  Betahistine Seven RCTs (548 participants) addressed this comparison. However, we were unable to conduct any meta-analyses for our primary outcomes as not all outcomes were considered by every study, and studies that did report the same outcome used different time points for follow-up, or assessed the outcome using different methods. Therefore, we were unable to draw meaningful conclusions from the numerical results. Some data were available for each of our primary outcomes, but the evidence was low- or very low-certainty throughout. One study reported on the outcome 'improvement in vertigo' at 6 to ≤ 12 months, and another study reported this outcome at > 12 months. Four studies reported on the change in vertigo, but again all used different methods of assessment (vertigo frequency, or a global score of vertigo severity) or different time points. A single study reported on serious adverse events.  Diuretics Two RCTs addressed this comparison. One considered the use of isosorbide (220 participants), and the other used a combination of amiloride hydrochloride and hydrochlorothiazide (80 participants). Again, we were unable to conduct any meta-analyses for our primary outcomes, as only one study reported on the outcome 'improvement in vertigo' (at 6 to ≤ 12 months), one study reported on change in vertigo (at 3 to < 6 months) and neither study assessed serious adverse events. Therefore, we were unable to draw meaningful conclusions from the numerical results. The evidence was all very low-certainty.  Other pharmacological interventions We also identified one study that assessed antivirals (24 participants), and one study that assessed corticosteroids (16 participants). The evidence for these interventions was all very low-certainty. Again, serious adverse events were not considered by either study.

AUTHORS' CONCLUSIONS

The evidence for systemic pharmacological interventions for Ménière's disease is very uncertain. There are few RCTs that compare these interventions to placebo or no treatment, and the evidence that is currently available from these studies is of 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-analyses of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits.

Positive pressure therapy for Ménière's disease

BACKGROUND

Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. It is often treated with medication, but different interventions are sometimes used. Positive pressure therapy is a treatment that creates small pressure pulses, generated by a pump that is attached to tubing placed in the ear canal. It is typically used for a few minutes, several times per day. The underlying cause of Ménière's disease is unknown, as is the way in which this treatment may work. The efficacy of this intervention at preventing vertigo attacks, and their associated symptoms, is currently unclear.

OBJECTIVES

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

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; 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 positive pressure therapy with either placebo or no treatment. We excluded studies with follow-up of less than three months.  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. 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 three studies with a total of 238 participants, all of which compared positive pressure using the Meniett device to sham treatment. The duration of follow-up was a maximum of four months.  Improvement in vertigo A single study assessed whether participants had an improvement in the frequency of their vertigo whilst using positive pressure therapy, therefore we are unable to draw meaningful conclusions from the results.  Change in vertigo Only one study reported on the change in vertigo symptoms using a global score (at 3 to < 6 months), so we are again unable to draw meaningful conclusions from the numerical results. All three studies reported on the change in the frequency of vertigo. The summary effect showed that people receiving positive pressure therapy had, on average, 0.84 fewer days per month affected by vertigo (95% confidence interval from 2.12 days fewer to 0.45 days more; 3 studies; 202 participants). However, the evidence on the change in vertigo frequency was of very low certainty, therefore there is great uncertainty in this estimate.   Serious adverse events None of the included studies provided information on the number of people who experienced serious adverse events. It is unclear whether this is because no adverse events occurred, or whether they were not assessed and reported.  AUTHORS' CONCLUSIONS: The evidence for positive pressure therapy for Ménière's disease is very uncertain. There are few RCTs that compare this intervention to placebo or no treatment, and the evidence that is currently available from these studies is of 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-analyses of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits.

Nutraceuticals for Peripheral Vestibular Pathology: Properties, Usefulness, Future Perspectives and Medico-Legal Aspects

Vestibular disorders may generate complex signs and symptoms, which may alter patients' balance and the quality of life. Dizziness and vertigo can strongly affect daily activities and relations. Despite the presence of conventional drugs, maneuvers, and surgery, another interesting therapeutic opportunity is offered by nutraceuticals. These molecules are often used in the treatment of dizziness and vertigo, but the rationale of their application is not always solidly demonstrated by the scientific evidence. Several substances have shown a variable level of efficacy/usefulness in this field, but there is lack of important evidence for most of them. From a medico-legal point of view, specific information must be provided to the patient regarding the efficacy and possibilities that the use of these preparations can allow. Administering the right nutraceutical to the proper patient is a fundamental clinical skill. Integrating conventional drug treatment with nutraceutical administration seems to be easy, but it may be difficult considering the (in part unexplored) pharmacodynamics and pharmacokinetics of nutraceuticals. The aim of the scientific community should be to elevate nutraceuticals to the same law and technical dignity of conventional drugs.

The role of endogenous Antisecretory Factor (AF) in the treatment of Ménière's Disease: A two-year follow-up study. Preliminary results

PURPOSE

To evaluate the effects of increased endogenous Antisecretory Factor (AF) synthesis using specially processed cereals (SPC) in a sample of patients with defined unilateral Meniere's disease (MD), compared to the results of a treatment protocol of intravenous glycerol and dexamethasone.

MATERIALS AND METHODS

Twenty-six patients with unilateral MD were divided in 2 groups and treated with SPC and with intravenous glycerol and dexamethasone for 24 months. Audio-vestibular evaluation was performed before (T0) and every six months. The number of vertigo spells were evaluated before and after therapy and the Efficacy Index (EI) was calculated. Questionnaires for hearing loss, tinnitus and quality of life were administered.

RESULTS

EI decreased in the SPC group after 18 (T18) (p = .0017) and 24 (T24) months of therapy (p = .0111). There was a significant reduction for tinnitus score in the SPC group at T24 (p = .0131). No significant differences were found between the two groups at T0 (p = .4723), while a significant difference was found at T24 (p = .0027). Quality of life showed a significant improvement in daily activities in the SPC group (p = .0033) compared to the infusion therapy group. No statistically significant changes in PTA thresholds were found in both groups between T0 and T24.

CONCLUSION

The preliminary results of our study show a significant reduction of vertigo spells and a positive effect on tinnitus severity and on quality of life in patients with unilateral MD treated with SPC and when compared to patients treated with intravenous glycerol and dexamethasone. No effects on hearing thresholds were noted in both groups.

Limbic System Associated Membrane Protein Mutation in an Iranian Family Diagnosed with Ménière's Disease

BACKGROUND

Ménière's disease (MD) is a common inner ear disorder which is characterized by recurrent attacks of vertigo, fluctuating sensorineural hearing loss (SNHL), tinnitus, and a sense of fullness in the affected ear. MD is a complex disorder; although six genes have been linked to familial autosomal dominant form of the disease, in many cases, the exact genetic etiology remains elusive.

METHODS

To elucidate the genetic causes of MD in an Iranian family, we performed exome sequencing on all members of the family: consanguineous parents and four children (two affected and two unaffected). Variant filtering was completed using a customized workflow keeping variants based on segregation with MD in autosomal recessive (AR) inheritance pattern, minor allele frequency (MAF), and in-silico prediction of pathogenicity.

RESULTS

Analysis revealed that in this family, 970 variants co-segregated with MD in AR pattern, out of which eight variants (one intergenic, four intronic, and three exonic) were extremely rare. The exonic variants included a synonymous substitution in USP3 gene, an in-frame deletion in ZBED2 gene, and a rare, highly conserved deleterious missense alteration in LSAMP gene.

CONCLUSION

The phenotype observed in the proband described here, i.e. vertigo, poor sense of smell, tinnitus, and borderline hearing ability, may originate from aberrant changes in the cerebellum and limbic system due to a deleterious mutation in the LSAMP gene; hence, LSAMP mutation is a possible candidate for the etiology of MD in this family.

Single Cell and Single Nucleus RNA-Seq Reveal Cellular Heterogeneity and Homeostatic Regulatory Networks in Adult Mouse Stria Vascularis

The stria vascularis (SV) generates the endocochlear potential (EP) in the inner ear and is necessary for proper hair cell mechanotransduction and hearing. While channels belonging to SV cell types are known to play crucial roles in EP generation, relatively little is known about gene regulatory networks that underlie the ability of the SV to generate and maintain the EP. Using single cell and single nucleus RNA-sequencing, we identify and validate known and rare cell populations in the SV. Furthermore, we establish a basis for understanding molecular mechanisms underlying SV function by identifying potential gene regulatory networks as well as druggable gene targets. Finally, we associate known deafness genes with adult SV cell types. This work establishes a basis for dissecting the genetic mechanisms underlying the role of the SV in hearing and will serve as a basis for designing therapeutic approaches to hearing loss related to SV dysfunction.

On the classification of hydropic ear disease (Menière's disease)

More than 150 years after its initial description by Prosper Menière, the disease named after him is still at the center of scientific debates. Two recent developments have specifically created a breeding ground for controversy: (1) Since its first description 10 years ago, magnetic resonance imaging diagnosis of endolymphatic hydrops in living patients has seen an increasing and worldwide application. (2) The Bárány Society Classification Committee published diagnostic criteria for Menière's disease in 2015 and proposed a concept of the disease that has elicited widespread criticism. In order to promote the understanding of the underlying controversies and arguments, this article gives an overview of and discusses relevant classification proposals for Menière's disease, including the new classification system of hydropic ear disease.

The cardiovascular aspects of a Ménière's disease population - A pilot study

Introduction

MD is considered a rare disease. An adequate model that explains MD's pathophysiology is not well established. Recently, the vascular theory of the disease has been revived.

Objectives

To characterize a MD population according to its cardiovascular risk and correlate it to the MD clinical course.

Methods

In this retrospective chart study the data of 31 MD patients observed between January 2017 and April 2018 in a tertiary university hospital were reviewed. Patients included in the study were diagnosed according to the Bárány Society criteria. Lost follow-ups, patients with autoimmune disease, atopy or allergy, major psychiatric disease and migraine were excluded. Age, gender, cardiovascular risk factors, audiometric and vestibular parameters, occurrence of MD attacks in the previous 6 months, vestibular medication in course and time course of MD were recorded and compared between groups (with and without cardiovascular risk factors).

Results

31 patients (61.3% females) mean aged 60.3 years (±9.7) were studied. 74% of the population had at least one risk factor and 51.6% of patients had attacks in the last 6 months. There was a statistically significant difference in the occurrence of MD attacks in the last 6 months (p = 0.014) between MD patients with and without risk factors. Mean PTA thresholds were higher and speech discrimination was lower in individuals with more cardiovascular risk factors.

Conclusions

Treatment of MD focusing on vascular risk factors may allow a better control of symptoms and result in a decreased need for ablative procedures in this disorder.

Saccular otoconia as a cause of Ménière's disease: hypothesis based on two theories

BACKGROUND

The cause of Ménière's disease remains enigmatic after 156 years. Schuknecht's rupture and potassium intoxication theory of attacks was based on histological studies.

OBJECTIVES

This paper aimed to: present the most contemporary evidence indicating that ruptures do not usually occur, and discuss the possibility that detached saccular otoconia are the main cause of Ménière's disease; and to establish an unequivocal definition of the age of Ménière's disease onset.

METHOD

The paper reviews the electrophysiological basis of the Gibson-Arenberg drainage theory used to explain vertigo attacks. The current, limited knowledge of the likely fate of detached saccular otoconia is discussed.

RESULTS

Electrophysiological studies during attacks do not support endolymph ruptures, but rather endolymph flowing in one direction and then in the opposite direction. Age of onset for Ménière's disease parallels that for benign paroxysmal positional vertigo.

CONCLUSION

The similarity of age of onset spectrum for Ménière's disease and benign paroxysmal positional vertigo raises the possibility that the two conditions have the same fundamental cause.

X-Linked Sensorineural Hearing Loss: A Literature Review

Sensorineural hearing loss is a very diffuse pathology (about 1/1000 born) with several types of transmission. X-linked hearing loss accounts for approximately 1% - 2% of cases of non-syndromic forms, as well as for many syndromic forms. To date, six loci (DFNX1-6) and five genes (PRPS1 for DFNX1, POU3F4 for DFNX2, SMPX for DFNX4, AIFM1 for DFNX5 and COL4A6 for DFNX6) have been identified for X-linked non-syndromic hearing loss. For the syndromic forms, at least 15 genes have been identified, some of which are also implicated in non-syndromic forms. Moreover, some syndromic forms, presenting large chromosomal deletions, are associated with mental retardation too. This review presents an overview of the currently known genes related to X-linked hearing loss with the support of the most recent literature. It summarizes the genetics and clinical features of X-linked hearing loss to give information useful to realize a clear genetic counseling and an early diagnosis. It is important to get an early diagnosis of these diseases to decide the investigations to predict the evolution of the disease and the onset of any other future symptoms. This information will be clearly useful for choosing the best therapeutic strategy. In particular, regarding audiological aspects, this review highlights risks and benefits currently known in some cases for specific therapeutic intervention.

Variants in the KCNE1 or KCNE3 gene and risk of Ménière's disease: A meta-analysis

BACKGROUND

Ménière's disease (MD) is defined as an idiopathic disorder of the inner ear characterized by the triad of tinnitus, vertigo, and sensorineural hearing loss. Although many studies have evaluated the association between variants in the KCNE1 or KCNE3 gene and MD risk, debates still exist.

OBJECTIVE

Our aim is to evaluate the association between KCNE gene variants, including KCNE1 rs1805127 and KCNE3 rs2270676, and the risk of MD by a systematic review.

METHODS

We searched the literature in PubMed, SCOPUS and EMBASE through May 2015. We calculated pooled odds ratios (OR) and 95% confidence intervals (CIs) using a fixed-effects model or a random-effects model for the risk to MD associated with different KCNE gene variants. The heterogeneity assumption decided the effect model.

RESULTS

A total of three relevant studies, with 302 MD cases and 515 controls, were included in this meta-analysis. The results indicated that neither the KCNE1 rs1805127 variant (for G vs. A: OR = 0.724, 95%CI 0.320, 1.638, P= 0.438), nor the KCNE3 rs2270676 variant (for T vs. C: OR = 0.714, 95%CI 0.327, 1.559, P = 0.398) was associated with MD risk.

CONCLUSIONS

Based on current evidence from published studies, neither of the two variants from KCNE was significantly associated with the risk of MD. Larger studies with mixed ethnicity subjects and stratified by clinical and sub-clinical characteristics are needed to validate our findings.

An Exploratory Study to Detect Ménière's Disease in Conventional MRI Scans Using Radiomics

OBJECTIVE

The purpose of this exploratory study was to investigate whether a quantitative image analysis of the labyrinth in conventional magnetic resonance imaging (MRI) scans using a radiomics approach showed differences between patients with Ménière's disease (MD) and the control group.

MATERIALS AND METHODS

In this retrospective study, MRI scans of the affected labyrinths of 24 patients with MD were compared to the MRI scans of labyrinths of 29 patients with an idiopathic asymmetrical sensorineural hearing loss. The 1.5- and 3-T MRI scans had been previously made in a clinical setting between 2008 and 2015. 3D Slicer 4.4 was used to extract several substructures of the labyrinth. A quantitative analysis of the normalized radiomic image features was performed in Mathematica 10. The image features of the two groups were statistically compared.

RESULTS

For numerous image features, there was a statistically significant difference (p-value <0.05) between the MD group and the control group. The statistically significant differences in image features were localized in all the substructures of the labyrinth: 43 in the anterior semicircular canal, 10 in the vestibule, 22 in the cochlea, 12 in the posterior semicircular canal, 24 in the horizontal semicircular canal, 11 in the common crus, and 44 in the volume containing the reuniting duct. Furthermore, some figures contain vertical or horizontal bands (three or more statistically significant image features in the same image feature). Several bands were seen: 9 bands in the anterior semicircular canal, 1 band in the vestibule, 3 bands in the cochlea, 0 bands in the posterior semicircular canal, 5 bands in the horizontal semicircular canal, 3 bands in the common crus, and 10 bands in the volume containing the reuniting duct.

CONCLUSION

In this exploratory study, several differences were found in image features between the MD group and the control group by using a quantitative radiomics approach on high resolution T2-weighted MRI scans of the labyrinth. Further research should be aimed at validating these results and translating them in a potential clinical diagnostic method to detect MD in MRI scans.

Motion Sickness: Current Knowledge and Recent Advance

Motion sickness (MS) is a common physiological response to real or virtual motion. Numerous studies have investigated the neurobiological mechanism and the control measures of MS. This review summarizes the current knowledge about pathogenesis and pathophysiology, prediction, evaluation, and countermeasures of MS. The sensory conflict hypothesis is the most widely accepted theory for MS. Both the hippocampus and vestibular cortex might play a role in forming internal model. The pathophysiology focuses on the visceral afference, thermoregulation and MS-related neuroendocrine. Single-nucleotide polymorphisms (SNPs) in some genes and epigenetic modulation might contribute to MS susceptibility and habituation. Questionnaires, heart rate variability (HRV) and electrogastrogram (EGG) are useful for diagnosing and evaluating MS. We also list MS medications to guide clinical practice. Repeated real motion exposure and combined visual-vestibular interaction training accelerate the progress of habituation. Behavioral and dietary countermeasures, as well as physiotherapy, are also effective in alleviating MS symptoms.