Menière's disease: pathophysiology and treatment

Symptom networks analysis among people with Meniere's disease: Application for nursing care

Objectives

This study aimed to explore and visualize the relationships among multiple symptoms in patients with Meniere's disease (MD) and aid clinical nurses in the design of accurate, individualized interventions.

Methods

This study included 790 patients with MD at the Eye and ENT Hospital of Fudan University from October 2014 to December 2021. A self-designed symptom checklist was used to assess 15 MD-related symptoms and construct contemporaneous networks with all 15 symptoms in R software. Qgraph package and Fruchterman-Reingold layout were used for network visualization. Bootstrapping methods were performed to assess network accuracy and stability, and three centrality indices were adopted to describe relationships among symptoms.

Results

Symptom networks showed good accuracy and stability. "Anxiety and nervousness"(98.2%), "aural fullness"(84.4%) and "tinnitus"(82.7%) were the common symptom in MD patients, while "tinnitus", "aural fullness" and "decline in word recognition", were more serious. MD patients with longer disease duration had higher prevalence and severity for all symptoms (P < 0.05). Symptom networks showed good accuracy and stability. "Decline in word recognition," "fatigue," and "anxiety and nervousness" were at the center of the symptom networks, which had the largest strength values and closeness. "Decline in word recognition," "headache," and "spatial discrimination and poor orientation" were the symptoms with the highest betweenness with the strongest bridging effect. The ≥1-year disease group exhibited higher centralities for "drop attack" and "anxiety and nervousness," and a lower centrality for "headache" compared with the <1-year disease group.

Conclusions

The symptom networks of MD patients with varying disease durations were revealed. Clinicians and nurses must provide precision interventions tailored to modifying symptom severity and centrality. Nursing interventions should focus on word recognition issues and associated discomfort in MD patients with multiple symptoms.

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

OBJECTIVE

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

STUDY DESIGN

Retrospective cohort.

SETTING

Tertiary academic medical center.

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Clinical characteristics and prognosis of acute low-frequency hearing loss and ascending sensorineural sudden sensorineural hearing loss

Objective

The present study aimed to explore the pathogenesis of the ascending sudden sensorineural hearing (SSNHL) loss by comparing the clinical characteristics and prognosis of acute low-frequency hearing loss (ALFHL) and ascending SSNHL.

Methods

A total of 43 patients with ALFHL and 122 patients with ascending SSNHL were enrolled in this study. First, the prognosis of patients with ALFHL and ascending SSNHL were compared, and the prognostic factors of AFHL and ascending SSNHL were analyzed.

Results

Acute low-frequency hearing loss and ascending SSNHL have no remarkable difference in complete recovery rate. Compared to ascending SSNHL, ALFHL has younger onset age, female prevalence, lower hearing threshold, shorter time from onset to recovery, and a lower proportion of combined tinnitus. The PTA at admission and delay from onset to therapy were significantly related to the prognosis of patients with ascending SSNHL, while only delay from onset to therapy was significantly related to the prognosis of patients with ALFHL. The majority of patients with ascending SSNHL and ALFHL recovered completely within 10 days from onset.

Conclusion

Audiogram shape plays a critical role in the prognosis of SSNHL. Ascending SSNHL and ALFHL may share a common pathological mechanism.

Development and Characteristics of Hearing Loss With the Progression of Endolymphatic Hydrops

OBJECTIVES

This study aims to explore how patients' hearing loss developed with the progression of endolymphatic hydrops and the characteristics of hearing loss at different stages.

MATERIALS AND METHODS

We collected 73 patients with definite or possible unilateral Meniere's disease or sudden hearing loss who underwent magnetic resonance imaging after intravenous contrast agent injection. There were 25 cases of isolated cochlear hydrops, 24 cases of isolated vestibular hydrops, and 24 cases of cochlear and vestibular hydrops. Primary outcome analyses included their evaluation of endolymphatic hydrops and hearing thresholds at low and high frequencies.

RESULTS

The overall hearing threshold of patients with vestibular and cochlear hydrops was significantly higher than that of patients with isolated cochlear hydrops and patients with isolated vestibular hydrops. There was a significant correlation between low-frequency hearing loss and cochlear hydrops, and the low-frequency hearing threshold was proportional to the grade of cochlear hydrops. At low frequency, the hearing threshold of patients with isolated vestibular hydrops was lower than that of patients with isolated cochlear hydrops and patients with both cochlear and vestibular hydrops. The audiogram configurations of patients with isolated cochlear hydrops consist largely of flat type and up-sloping type. The audiogram configurations of patients with isolated vestibular hydrops and patients with both cochlear and vestibular hydrops are mainly flat type and down-sloping type.

CONCLUSIONS

Patients present with low-frequency hearing loss in the early stage of endolymphatic hydrops. When the hydrops involves the whole cochlea and vestibule, the patients' hearing is impaired at both low and high frequencies.

Retrosigmoid Vestibular Neurectomy for Meniere's Disease: a technical note

BACKGROUND AND OBJECTIVE

Meniere's disease (MD) is an idiopathic peripheral pathology involving the acoustic apparatus. One of the most critical challenges in managing MD is intractable vertigo. In this context, the retrosigmoid vestibular neurectomy (RVN) has been described as a safe and effective technique to manage this symptom when resistant to first- and second-line treatments. In this article, the alternative treatment options, specific surgical anatomy, and relevant details to perform vestibular neurectomies for intractable MD are analyzed.

METHODS

Relevant neurovascular landmarks, critical surgical steps, adequate indications, and potential pitfalls of the RVN were analyzed based on an illustrative clinical case of intractable MD.

RESULTS

The illustrative case demonstrated how early recognition of the facial nerve and the vestibulo-cochlear plane is fundamental to performing RVN. This procedure is indicated in cases of resistant MD with pre-operative hearing integrity. Potential pitfalls of this technique are incomplete neurotomy, nerve regeneration, comorbidities in the contralateral ear, adverse anatomy, the possibility of non-otologic vertigo, and incomplete vestibular compensation.

CONCLUSIONS

Vestibular neurectomy represents a safe and effective technique in managing intractable MD resistant to medical treatment, allowing symptom control and hearing preservation. Nevertheless, detailed knowledge of surgical anatomy, as well as possible pitfalls, is of paramount importance to achieve a good outcome.

Association between Meniere's disease and air pollution in South Korea

Meniere's disease is thought to be a disorder of the inner ear function, affected by genetic and environmental factors. Several recent studies have shown that air pollution could affect middle and inner ear diseases. The purpose of this study was to investigate the relationship between the Meniere's disease occurrence and air pollution status in Korea. This study used a time-stratified case-crossover design. Hospital visit data by Meniere's disease were collected from the Korea National Health Insurance Service-National Sample Cohort (NHIS-NSC) database. Daily air pollution data for sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and particulate matter (PM10: ≤ 10 μm in diameter, and PM2.5: ≤ 2.5 μm in diameter) were collected from the National Ambient air quality Monitoring Information System (NAMIS) database. We used two-stage analysis to assess the association between degree of air pollution and the occurrence of Meniere's disease. In the first stage, region-specific analysis was conducted to estimate the odds ratios (ORs) of Meniere's disease risk associated with each air pollutant exposure by using conditional logistic regression for matched case-control sets in 16 regions. In the second stage, region-specific ORs from the first stage were combined and the pooled effect estimates were derived through fixed and random effect meta-analysis. Subgroup analysis was conducted for age, sex, seasonality, and urbanization of residence. In total, 29,646 (32.1% males and 67.9% females) Meniere's disease cases were identified from Korea NHIS-NSC database between 2008 and 2015. Overall, SO2, NO2, CO, and PM10 showed significant correlation with Meniere's disease risk at immediate lags, and weaker correlation at delayed lags, whereas O3 showed slightly negative correlation at the immediate lag (lag0) and PM2.5 did not show strong correlation (SO2: 1.04 [95% confidence interval: 1.01, 1.06]; NO2: 1.08 [1.06, 1.11]; CO: 1.04 [1.02, 1.06]; O3: 0.96 [0.93, 0.99]: statistically significant ORs at lag0 are listed). These positive and negative associations between Meniere's disease and each air pollutant were generally stronger in the age of 40-64, female, summer (June-August) season, and urban subgroups. Our results showed that hospital visits for Meniere's disease were associated with the measured concentrations of ambient air pollutants SO2, NO2, CO, and PM10. Further studies are required to confirm these associations and find their mechanisms.

Visualization of Endolymphatic Hydrops in Patients With Unilateral Idiopathic Sudden Sensorineural Hearing Loss With Four Types According to Chinese Criterion

Objective: The aim of this study is to evaluate the possible value of endolymphatic hydrops (EH) in patients with unilateral idiopathic sudden sensorineural hearing loss (UISSNHL) with four types according to audiometry.

Methods: Seventy-two patients (40 men and 32 women; age range, 28–78 years; mean age: 50.0 ± 12.9 years) with UISSNHL were admitted retrospectively into this study. Based on the pure tone audiometry before treatment, the hearing loss of all these patients were categorized into four types: low-frequency group (LF-G), high-frequency group (HF-G), flat group (F-G), and total deafness group (TD-G). The average time from symptom onset to the first examination was 6.9 ± 4.4 days (1–20 days). 3D-FLAIR MRI was performed 24 h after intratympanic injection of gadolinium (Gd) within 1 week after the UISSNHL onset. The incidence of EH in the affected ears based on four types of hearing loss were analyzed using the Chi-square test, and the possible relationship with vertigo and prognosis were also assessed.

Results: Eleven of 21 patients (52.4%) in LF-G had the highest EH-positive rate, followed by 18.2% in HF-G, 11.8% in F-G, and 17.4% in TD-G. The significant difference was found in the four groups (P = 0.018). The EH rate of LF-G was statistically significantly higher than that of F-G and TD-G (P = 0.009, P =0.014), respectively. After being valued by the volume-referencing grading system (VR scores), the EH level was represented by the sum scores of EH. In LF-G, no statistically significant difference was found in the prognosis of ISSNHL patients between with the EH group and the no EH group (P = 0.586). The symptom “vertigo” did not correlate with EH and prognosis.

Conclusions: EH was observed in UISSNHL patients by 3D-FLAIR MRI. EH may be responsible for the pathology of LF-G but not related to prognosis. It might be meaningless to assess EH in other hearing loss types, which might be more related to the blood-labyrinth dysfunction.

Analysis of wideband tympanometry in Ménière's disease

Introduction

Endolymphatic hydrops is the pathophysiological substrate of Ménière’s disease. The changes in the inner ear, transmitted to the middle ear through changes in the ossicular chain mobility, can be quantified by wideband tympanometry, through the measurement of the acoustic absorbance at multiple frequencies, represented by the sound energy absorbed by the middle ear, even at its early stages. Studying the behavior of the middle ear through the absorbance in patients with endolymphatic hydrops under ambient pressure and under peak pressure can be useful for detecting Ménière's disease.

Objective

To characterize acoustic absorbance behavior in subjects with symptomatic and asymptomatic Ménière's disease compared to controls, in order to verify the ability of wideband tympanometry to detect Ménière's disease.

Methods

We carried out a cross-sectional study with a diagnostic approach comparing the findings of wideband tympanometry at ambient pressure and peak pressure between the ears of the control group (n = 30), the asymptomatic group (n = 21) and the symptomatic group (n = 9).

Results

Different peak pressure values were found between the ears of the control group (0 daPa), the asymptomatic group (−11 daPa) and the symptomatic group (−192 daPa), with p < 0.05 by the Kruskal-Wallis test, Mann Whitney test and Bonferroni correction. Different absorbance values were found between the ears of the symptomatic group and the asymptomatic group compared to the control group for low frequencies at ambient pressure and peak pressure, with p < 0.05 by the Kruskal-Wallis test, Mann Whitney test and Bonferroni correction.

Conclusions

The Wideband Tympanometry test was capable of identifying the presence of Ménière´s disease, and to differentiate between asymptomatic and symptomatic patients, when comparing them with healthy individuals.

Hold the Salt: History of Salt Restriction as a First-line Therapy for Menière's Disease

OBJECTIVES

To determine the historical origins of the usage of the salt restriction diet as an intervention for Menière's disease (MD).

METHODS

Articles on MD and salt restriction were identified using Pubmed and Google scholar. Original manuscripts from 19th and 20th century as well as selected otological textbooks in English, German, and French were also reviewed.

RESULTS

The oldest recommendation of salt restriction in the literature was by Dederding (1889-1955) in 1929. She and her mentor, Sydney Holger Mygind (1884-1970), believed MD was caused by dysfunctional water metabolism. In several published manuscripts, they proposed that a reduced salt and fluid diet was an effective treatment for MD. Their contemporaries supported their findings, most notably, Albert C. Furstenberg (1890-1969) who suggested salt restriction alone as treatment for MD. Furstenberg, in his initial study implementing salt restriction in 15 patients with MD and then in a larger study with 150 patients, was the first to produce results that supported salt restriction as therapy for MD. It was not until 1980, when LB Jongkees first published his criticism of this treatment, that salt restriction was questioned. Since then, numerous published articles have been critical of salt restriction therapy and skeptical of its initial adoption into clinical practice.

CONCLUSIONS

Since Dederding's and Mygind's publications in 1929 and Furstenberg's trial in 1934, the salt restriction diet has remained a primary first-line treatment for MD. Since the 1950s, various publications have both supported and argued this treatment, and the evidence of its validity remains inconclusive.

Remission of Recurrent Cochlear Hydrops Associated With Bromocriptine Treatment for Macroprolactinoma

Objective Current recommendations for cochlear hydrops treatment include systemic glucocorticoids and diuretics. Cochlear cells express dopamine receptors, although their role is unknown in the pathophysiology of cochlear hydrops. Case Description We report the case of remission of recurrent right-sided cochlear hydrops in a young male patient treated with bromocriptine due to pituitary macroprolactinoma. Transient improvement was observed after oral steroid and diuretic treatment, but cochlear hydrops recurred until the dose of bromocriptine was increased to 10 mg daily. Conclusion Bromocriptine may stimulate dopamine receptors in cochlear cells with potential therapeutic role in patients with cochlear hydrops. There are no widely accepted and effective treatments for endolymphatic hydrops, and identifying potential new and efficacious therapeutics is of high relevance.

Ménière's Syndrome or Disease: Time Trends in Management and Quality of Evidence Over the Last Two Decades

OBJECTIVE

To evaluate the evidence and trends in published literature on the treatment of Ménière's syndrome or disease (MS/D) by comparing studies published in the last two decades.

DATA SOURCES

A literature search was performed on AMED, EMBASE, HMIC, MEDLINE, PsycINFO, BNI, CINAHL, HEALTH BUSINESS ELITE, CENTRAL and Cochrane Ear, Nose and Throat disorders groups trials register using a combination of MeSH. The date of last search was October 2014.

STUDY SELECTION AND DATA EXTRACTION

Two hundred five studies (104 in decade I and 101 in decade II) were evaluated to report trends in the management of this condition, the differing levels of evidence published for each treatment modality, evaluate whether the guidelines published by the AAOHNS-Committee on Hearing and Equilibrium had been correctly employed, and whether the randomized controlled trials (RCTs) were compliant with the CONSORT guidelines.

RESULTS

The number of published RCTs almost tripled from decade I (1994-2003) to decade II (2004-2103). There was a significant decline in the use of surgical intervention (p = 0.013); however, the number of studies involving the use of intratympanic injection remained largely unchanged. There was a shift in the level of evidence in published studies; studies with level 1 evidence tripled from decade I to II (4.8 to 17.8%, respectively) (p = 0.03); however, compliance with the AAOHNS-CHE criteria for reporting treatment outcomes and the CONSORT checklist was still poor.

CONCLUSION

Although the evidence base on published literature on MS/D has improved over the last decade with an increase in emphasis on RCTs and quality of life (QoL) studies, a significant number of studies failed to follow AAOHNS-CHE criteria for reporting treatment outcome and the CONSORT criteria for reporting RCTs.

Glycerol-induced fluid shifts attenuate the vestibulosympathetic reflex in humans

The glycerol dehydration test (GDT) has been used to test for the presence of Ménière's disease and elicits acute alterations in vestibular reflexes in both normal and pathological states. Activation of the vestibulosympathetic reflex (VSR) increases muscle sympathetic nerve activity (MSNA) and peripheral vascular resistance. We hypothesized that the GDT would attenuate the VSR through fluid shifts of the inner ear. Sixteen male subjects (26 ± 1 yr) were randomly assigned to be administered either glycerol mixed with cranberry juice (97 ± 3 ml glycerol + equal portion of cranberry juice; n = 9) or a placebo control [water + cranberry juice (100 ml each); n = 7]. Subjects in both groups performed head-down rotation (HDR), which engages the VSR, before and after administration of either the glycerol or placebo. MSNA (microneurography), arterial blood pressure, and leg blood flow (venous occlusion plethysmography) were measured during HDR. Before glycerol administration, HDR significantly increased MSNA burst frequency (Δ8 ± 1 bursts/min; P < 0.01) and total activity (Δ77 ± 18%; P < 0.01) and decreased calf vascular conductance (-Δ20 ± 3%; P < 0.01). However, HDR performed postadministration of glycerol resulted in an attenuated MSNA increase (Δ3 ± 1 bursts/min, Δ22 ± 3% total activity) and decrease in calf vascular conductance (-Δ7 ± 4%). HDR significantly increased MSNA burst frequency (Δ5 ± 1 and Δ5 ± 2 bursts/min) and total activity (Δ58 ± 13% and Δ52 ± 18%) in the placebo group before and after placebo, respectively (P < 0.01). Likewise, decreases in calf vascular conductance during HDR before and after placebo were not different (-Δ13 ± 4% and -Δ14 ± 2%, respectively; P < 0.01). These results suggest that fluid shifts of the inner ear via glycerol dehydration attenuate the VSR. These data provide support that inner ear fluid dynamics can have a significant impact on blood pressure regulation via the VSR in humans.

Medical and noninvasive therapy for Meniere's disease

Nonoperative therapy continues to be the mainstay of treatment of patients suffering from Meniere disease. Despite extensive research, the exact pathogenesis of Meniere disease remains elusive. The poorly understood nature of this condition has made it nearly impossible to develop treatments that are curative. Most modern treatments are aimed at controlling symptoms. This article reviews the various nonoperative treatments that have been used to treat Meniere disease historically as well as outlining the authors' clinical treatment paradigm.

Meniere's disease: update of etiopathogenetic theories and proposal of a possible model of explanation

Meniere's Disease (MD) is an affection consisting of an association of sensorineural hearing loss, tinnitus and vertigo initially presenting by crises. A review of the most considered possible causative factors and pathophysiologic interpretations allows us to underline the uncertainties which still exist about the genesis of this illness. We propose a mechanistic model based on the effect of a haemodynamic imbalance leading to transient ischaemia which could have an effect on the pH of the inner ear as well as on the work of the inner ear proton pumps. It is hypothesized that under ischaemic conditions and consequent metabolic acidity a preserved proton pump activity can generate an overload of anions in the endolymphatic partition, which is a closed system, thus resulting in an enhancement of osmolarity and consequently in the formation of a hydrops resulting in the development of fluctuating hearing loss, tinnitus and vertigo which characterize Meniere's Disease.

Preventing diet induced disease: bioavailable nutrient-rich, low-energy-dense diets

What the World needs is an integrated and sustainable food policy that makes the best and most appropriate use of the technologies at our disposal to promote health and help prevent disease. Diet induced diseases account for the largest burden of chronic illnesses and health problems Worldwide. Historically a lack of knowledge about human nutritional requirements (including for the brain) helped promote diet induced disease. The scientific knowledge currently exists to help prevent many of the current deficiencies and imbalances in human diet. Primary prevention of cardiovascular disease and mental ill health starts, crucially, with maternal nutrition before the inception of pregnancy and continues throughout life of the new born and includes consuming more DHA and EPA omega-3 fats (and their cofactors) and other bioavailable brain nutrients and less high-energy-dense (>2 kcal g(-1)) foods (e.g. land-based cereal, chocolate, alcohol and refined sugar, fat and oil), so tissues synthesize less inflammatory mediators and to lower transient short-lived meal-induced oxidative stress, inflammation, proliferation and impaired nitric oxide (e.g. approximately 0.35-3.5 g DHA/ EPA day(-1) dependant on energy intake and noting the importance of cofactors). Micro- and nanotechnologies are already engineering nano foods for human (and livestock) consumption that may eventually (without excessive consumption) prevent the current diet induced disease epidemic, especially in future generations, by preventing the causal mechanisms of disease. Greater knowledge about the causal mechanisms of disease awaits to be discovered, which could further enhance the human desire to increase longevity in optimum health (creating more problems and challenges for society).

Triple semicircular canal occlusion for the treatment of Ménière's disease

CONCLUSION

Triple semicircular canal occlusion (TSCO) controls vertigo, is easy to perform, and could be used as an alternative procedure for the treatment of Meniere's disease in selected patients who complain mainly of intractable vertigo.

OBJECTIVE

To seek an effective alternative surgical procedure for treating Ménière's disease in selected patients with intolerant rotational vertigo.

PATIENTS AND METHODS

Three patients with Ménière's disease who underwent unsuccessful endolymphatic sac decompression or mastoid shunt, then underwent TSCO. Vertigo control and vestibular and auditory function were measured.

RESULTS

The early vestibular symptoms caused by surgery resolved quickly and no hearing deterioration occurred after surgery. At the end of the follow-up period, based on the AAO-HNS criteria, two cases had complete control of vertigo (class A) and the other had substantial control of vertigo attacks (class B). Hearing was similar to the preoperative level at the end of the follow-up period.

Evaluation of the effect of dexamethasone in experimentally induced endolymphatic hydrops in guinea pigs

PURPOSE

The aim of this study was to investigate the audiological and histopathologic effects of dexamethasone in the treatment of experimentally induced endolymphatic hydrops.

MATERIALS AND METHODS

Thirty mature, male guinea pigs weighing 400 +/- 50 g were operated on to induce experimental endolymphatic hydrops in their right ear. Left ear served as control. Subjects were separated into control and dexamethasone groups, with the latter receiving dexamethasone 5 mg/(kg d) intraperitoneally for 10 days. Electrocochleography and auditory brainstem response were applied to all subjects at preoperation, on the second postoperative day and also on the 15th postoperative day in animals that lived for a long time. The histopathologic examination of the inner ear in all animals was done at the end of the study.

RESULTS

The summating potential and the ratio of the summating potential to the action potential measured on the second postoperative day were found to be increased in both groups, but more significantly in the control one. When the left and right ears were compared, significant difference was found in the control group; however, no significant difference was found between the ears in the dexamethasone group. Histopathologic examination revealed varying degrees of hydrops in the control group, but showed only normal findings or minor changes in the dexamethasone group.

CONCLUSIONS

Dexamethasone can prevent the audiological and histopathologic findings of experimentally induced endolymphatic hydrops. However, these results must be supported by clinical and experimental studies designed with a large number of subjects.

The outcome of patients with ménière’s disease

Ménière’s disease is a frequent vestibular disease that occurs predominantly in the fourth decade of life. Diagnosis is mostly medical and is based on findings of vertigo, sensorineural hearing loss, tinnitus and aural fullness. Aim: To study the clinical findings of Ménière’s disease: age, duration of vertigo, tinnitus, hearing loss and aural fullness, and unilateral or bilateral involvement. Method: a retrospective study included 39 patients with a diagnosis of Ménière’s disease confirmed by electrocochleography, who were seen at a neuro-otology referral centre. Patients underwent a clinical examination, audiometry and bilateral transtympanic electrocochleography. Patients were separated into 2 groups: bilateral Ménière’s disease and unilateral Ménière’s disease. Results: The mean age was 42.9 years; 72.5% were female. Fluctuation of hearing loss occurred in 54.5% of cases, and 65.7% had frequent attacks of vertigo. Bilateral disease was observed in 33.3%. The onset of the disease was earlier in the bilateral group (33.7 years) compared to the unilateral group (p= 0.0013). Duration of disease, tinnitus, hearing loss and aural fullness were similar between groups. Conclusion: Patients with bilateral Ménière’s disease had symptoms earlier than patients with unilateral disease. There was no difference between the groups in duration of disease and associated symptoms.

Evaluation of booklet-based self-management of symptoms in Ménière disease: a randomized controlled trial

OBJECTIVE

This study examined the effectiveness of booklet-based education in vestibular rehabilitation (VR) and symptom control (SC) techniques to manage vertigo and dizziness in Ménière disease.

METHODS

Participants (n = 360) were randomized to a waiting list control group or to receive either a VR or an SC self-management booklet. VR involved provoking dizziness in a controlled manner by making repeated head movements in order to promote neurological and psychological habituation. SC involved using applied relaxation, challenging negative beliefs, and lifestyle modification to reduce amplification of dizziness by anxiety. Subjective improvement in health, enablement (ability to understand and cope with symptoms), and adherence were measured at 3 and 6 months. Symptoms, handicap, anxiety and depression, and negative beliefs about symptoms were assessed pretreatment and at 3 and 6 months.

RESULTS

At 6-month follow-up, 45 (37.5%) of the VR group and 47 (39.2%) of the SC group reported improvement compared with 19 (15.8%) controls; the relative probability of improvement compared with controls was 2.37 (95% confidence interval [CI], 1.48-3.80) for VR and 2.47 (95% CI, 1.55-3.95) for SC. Both intervention groups reported greater enablement than controls (p < .001, d > 0.70). At 3 months, the VR group had reduced symptoms, anxiety, handicap, and negative beliefs about dizziness; the SC group had reduced handicap; but the control group showed no improvement. Reported adherence levels were low and strongly related to outcome.

CONCLUSIONS

Self-management booklets offer an inexpensive and easily disseminated means of helping people with Ménière disease to cope with dizziness symptoms.

Tinnitus and Brain Activation: Insights from Transcranial Magnetic Stimulation

The mechanisms underlying tinnitus are still not completely elucidated, but advances in neuroimaging and brain stimulation have provided us with new insights. Evidence suggests that tinnitus might actually be generated by central rather than peripheral structures. To illustrate the importance of brain activity changes in the pathology of tinnitus, we report the cases of 2 patients who experienced a recurrence/worsening of their tinnitus after they had undergone treatment for major depression with repetitive transcranial magnetic stimulation. We suggest that the tinnitus in these 2 patients was induced by changes in brain activity resulting from transcranial magnetic stimulation of the prefrontal cortex. We also review the pathophysiology and other aspects of tinnitus, focusing on associated brain reorganization.

[Diagnosis of endolymphatic hydrops using low frequency modulated distortion product otoacoustic emissions]

BACKGROUND

The low frequency modulation of distortion product otoacoustic emissions (DPOAEs) is an objective audiometric method that appears to be a useful tool for the diagnosis of endolymphatic hydrops (EH), e.g. in patients with Menière's disease, or in those who present only some of the symptoms of the disease.

METHOD

Low-frequency modulated DPOAEs were registered in 20 patients with unilateral Menière's disease (13 women and 7 men, aged 40-66 years) and were compared to a control group matched in age and gender. As a diagnostic parameter, the 'modulation index' MI=1/2 MS/DM was used (MS or modulation span, being the difference between the maximal and the minimal DPOAE-amplitude, and DM, being the mean of the suppressed stationary DPOAE-amplitude).

RESULTS

In the patients with unilateral Menière's disease, MI was lower than in the control group. This difference was highly significant. In 56% of the patients' contralateral ears MI was lower than the cut off-value and significantly lower than in the control group, but did not differ significantly from the patients' ipsilateral ears.

CONCLUSION

The registration of low-frequency modulated DPOAEs is comparable to the generally applied transtympanic electrocochleography in its diagnostic validity. The method is fast and non-invasive and could be applied to monitor the course of the disease.

Oral Administration of Prednisone to Control Refractory Vertigo in Ménière's Disease: A Pilot Study

OBJECTIVE

To establish whether the oral administration of moderate doses of prednisone reduces refractory vertigo in Ménière's disease.

STUDY DESIGN

Blinded, randomized, controlled trial.

SETTING

Tertiary referral center.

PATIENTS

Patients with Ménière's disease with limited vertigo control (Class C) and severe disability (Scale 3).

INTERVENTIONS

Two groups (n = 8 per group) were treated orally with either diphenidol (25 mg/d) plus acetazolamide (250 mg/48 h) (control group), or the same treatment plus prednisone (0.35 mg/kg) daily for 18 weeks (prednisone group).

MAIN OUTCOME MEASURES

The variables evaluated were the frequency and duration of vertigo, tinnitus, aural fullness, and audiographic parameters. The clinical surveillance was performed for 12 months after prednisone withdrawal.

RESULTS

The frequency and duration of vertigo episodes were reduced by 50% and 30%, respectively, by prednisone treatment. Prednisone-treated patients manifested a significant reduction in tinnitus. No changes were observed in aural fullness or hearing. No metabolic or infectious disorders were observed.

CONCLUSION

Oral prednisone helps to control refractory vertigo in Ménière's disease. These preliminary data suggest that prednisone can be a good noninvasive antivertigo management regimen for these patients.

Intratympanic gentamicin in monolateral Meniere’s disease: our experience

The aim of this study was to verify the efficacy of a modified Odkvist titration protocol of intratympanic gentamicin application in the control of vertigo attacks and the effects on the auditory and vestibular function in a group of 71 patients affected by monolateral MD resistant to medical therapy. All the patients underwent an intratympanic administration of a 1-ml solution containing 26.6 mg of gentamicin sulfate. The treatment protocol provided one to three injections for a total amount of gentamicin varying from 26.6 to 80 mg. Five days after the first gentamicin administration, cochlear and vestibular function tests were performed. The worsening of the PTA greater than 15 dB, the appearance of clinical signs of vestibulotoxicity such as imbalance or persistent spontaneous nystagmus beating away from the injected ear or of a "curative vertigo" were the criteria taken into consideration to stop the treatment. In the absence of any sign, a second and third injection were performed. The presence of an unchanged frequency of the attacks at least 3 months after the previous cycle was the parameter considered to perform a second or third cycle. Seventeen (24%) patients were submitted to a second cycle of therapy and two (3%) to a third cycle. After a mean follow-up period of 20.3 months (range: 3 to 48) all 71 patients experienced good control of the vertigo attacks: grade A in 46 cases and grade B in 25 cases according to the AAO-HNS CoHE criteria. The pure tone average (PTA) hearing threshold (500-3,000 Hz) worsened in 19 patients, improved in 5 and was unchanged in 47. On the basis of the experience acquired during the treatment, we progressively decreased the number of injections from 3/cycle to a 1-2/cycle of therapy. Moreover, in the later phase of the study re-injections were administered 1 or 2 weeks after the previous application and avoided in the presence of signs of depression of the vestibular and/or cochlear function. A residual caloric excitability was found in 30% of the cases. Vertigo control doesn't seem to be linked to the achievement of vestibular inexcitability. The marker of successful gentamicin treatment at short-term is the appearance of signs of curative vertigo and/or vestibular imbalance, and at long-term the disappearance of vertigo attacks.

Origins and evolution of the Western diet: health implications for the 21st century

There is growing awareness that the profound changes in the environment (eg, in diet and other lifestyle conditions) that began with the introduction of agriculture and animal husbandry approximately 10000 y ago occurred too recently on an evolutionary time scale for the human genome to adjust. In conjunction with this discordance between our ancient, genetically determined biology and the nutritional, cultural, and activity patterns of contemporary Western populations, many of the so-called diseases of civilization have emerged. In particular, food staples and food-processing procedures introduced during the Neolithic and Industrial Periods have fundamentally altered 7 crucial nutritional characteristics of ancestral hominin diets: 1) glycemic load, 2) fatty acid composition, 3) macronutrient composition, 4) micronutrient density, 5) acid-base balance, 6) sodium-potassium ratio, and 7) fiber content. The evolutionary collision of our ancient genome with the nutritional qualities of recently introduced foods may underlie many of the chronic diseases of Western civilization.