Neurotology of migraine

Neurotologic symptoms are common with migraine, yet relatively little is known about the pathophysiology of such symptoms. Motion sensitivity with bouts of motion sickness occurs in about two thirds of patients with migraine. Episodes of vertigo occur in about one fourth of patients and, in some, vertigo is the only symptom (so-called "migraine equivalent"). Phonophobia is the most common auditory symptom, but fluctuating hearing loss and acute permanent hearing loss occur in a small percentage. Migraine can mimic Meniere's disease and so-called "vestibular Meniere's disease" is usually associated with migraine. The recent discovery of a mutation in a brain calcium-channel gene in families with hemiplegic migraine and in families with episodic vertigo and ataxia suggests a possible mechanism for neurotologic symptoms in patients with more common varieties of migraine. A defective calcium channel, primarily expressed in the brain and inner ear, could lead to reversible hair cell depolarization and auditory and vestibular symptoms. This hypothesis is currently being investigated in other families with migraine headaches and neurotologic symptoms. Hopefully, such studies will lead to improved diagnosis and better treatments in the future.     

Use of glycopyrrolate in the treatment of Meniere's disease

OBJECTIVES/HYPOTHESIS: The objective of this study was to determine whether glycopyrrolate is useful as a vestibular suppressant in patients with Meniere's disease. The tested hypotheses were that glycopyrrolate would decrease the perception of dizziness measured by the Dizziness Handicap Inventory in patients with Meniere's disease and that placebo would cause no such decrease. STUDY DESIGN: Randomized, prospective. METHODS: Thirty-seven subjects with a diagnosis of Meniere's disease were administered either 2 mg of glycopyrrolate or placebo twice daily as needed for vertigo. All were also administered the regimen of 1500 mg sodium/day diet and diuretic. The following indices were examined: Dizziness Handicap Inventory, Tinnitus Handicap Inventory, Modified Somatic Perception Questionnaire, Beck Depression Inventory, hearing examination, and electronystagmography. After 4 to 6 weeks of the drug regimen, Dizziness Handicap Inventory, Tinnitus Handicap Inventory, Modified Somatic Perception Questionnaire, and Beck Depression Scale were reexamined. Paired t tests were performed to verify the significance of improvement before and after treatment. RESULTS: Subjects who received glycopyrrolate had statistically significant reduction in Dizziness Handicap Inventory, Beck Depression Score, and Modified Somatic Perception Score. In the placebo group, no improvement in any index was found. CONCLUSIONS: The hypothesis that glycopyrrolate is a useful vestibular suppressant in patients with Meniere's disease was statistically verified.     

The role of allergy in Meniere's disease

There is considerable clinical and immunologic evidence for a probable role of allergy in the production of the symptoms of Meniere's disease. The endolymphatic sac is the seat of immune reactivity in the inner ear. Inhalant and food allergies have been linked with symptoms of Meniere's disease, and many of the clinical characteristics of Meniere's disease suggest an underlying autoimmune etiology. A significant percentage of patients with Meniere's disease and allergy show improvement in their symptoms of tinnitus and vertigo when receiving specific allergy therapy.     

Infant pneumonia at periodic check-ups. Characteristics and associated factors]

The pathoetiology of Meniere's disease remains elusive. Histopathologic and imaging studies have implicated congenital or developmental abnormality of the endolymphatic duct as a likely predisposing factor to the development of endolymphatic hydrops and clinical Meniere's disease. Recently, improved high-resolution magnetic resonance imaging (MRI) protocols have allowed better demonstration of the soft tissues of the endolymphatic duct and sac. This study is a prospective evaluation of the ability of submillimeter MRI to detect the endolymphatic duct in Meniere's disease patients and control subjects. In addition, the development of the temporal bone in the region of the endolymphatic sac and duct is evaluated by measurements of the distance from the posterior semicircular canal to the subarachnoid space and the distance from the vestibule to the subarachnoid space. Visualization of the endolymphatic duct was found to be significantly less frequent in the Meniere's disease patients (29%) than in the control subjects (91%). Temporal bone measurements in the region of the endolymphatic duct showed patients with Meniere's disease to have smaller dimensions than control subjects.     

Meniere's disease of syphilitic etiology

Congenital or acquired syphilis is the cause of Meniere's disease in six percent of all cases. The pathogenesis is endolymphatic hydrops and osteitis of the otic capsule which produces the characteristic fluctuating hearing loss, tinnitus and ear pressure associated with episodic spells of vertigo. The ear symptoms are, at first, typical of Meniere's disease of other etiologies. Failure to establish the specific etiologic diagnosis can result in unnecessary surgical treatment or inappropriate medical therapy. In some cases, if a steroid, the specific treatment, is not given promptly, hearing can be quickly and permanently lost. The etiology is confirmed by obtaining a reactive fluorescent treponema antibody absorption (FTA-abs) test. The clinical features and natural history of Meniere's disease of syphilitic etiology are unique. Ear symptoms often begin in the fifth decade of life, first in one ear and, after a few years, involving the second ear. Reduced or absent caloric responses are characteristic. When hearing loss is severe and sudden, this condition represents a true medical emergency and should be treated with prompt administration of steroids. An endolymphatic subarachnoid shunt operation is occasionally necessary as adjunctive management. An analysis of 34 cases shows that long-term use of steroids can maintain effective hearing for more than 20 years.     

Prosper Ménière: unknown and little known facts]

In the article some less known and unknown facts from Prosper Meniere's life are reported. It was emphasized that in foreign bibliography etiology of Meniere's disease isn't connected with labyrinthine's hameorrhagia, as it is often stated in Polish laryngological literature.     

Intravenous xylocaine in the treatment of attacks on Meniere's disease

The effect of xylocaine on epileptic attacks suggested a study of its effect in attacks on Meniere's disease, as the symptoms can be very much alike in the two conditions. The results were found to be excellent, especially as regards the vegetative dysfunctions. In attacks of Meniere's disease the tinnitus disappeared for 20 minutes, vomiting generally disappeared for good and nausea for an hour or two. Nystagmus was unaffected.     

A partial area difference analysis for estimating elimination rate constants and distribution volumes of metabolites

A prospective, randomized study was carried out comparing the effect of two surgical modalities in the treatment of patients with Meniere's disease: insertion of an endolymphatic sac shunt and insertion of a ventilating tube in the tympanic membrane. A total of 29 patients, 12 males and 17 females, age 27-71 years, were operated on in two ear, nose and throat (ENT) departments. Of these patients, 15 had an endolymphatic shunt inserted and 14 had a ventilating tube inserted in the tympanic membrane. Postoperative follow-up was carried out in the department in which the patients had not been operated. The severity of the disease was scored pre- and postoperatively, and the results evaluated under the guidelines of the Committee on Hearing and Equilibrium (1995) for the diagnosis and evaluation of therapy in Meniere's disease. The patients in both groups had a statistically significant reduction in dizzy spells, measured 6 and 12 months postoperatively, and there was no difference between the groups. The pathophysiological explanation for the reduction in dizzy spells in each of the treatment modalities is debatable and the effect is non-specific. The patients' hearing and tinnitus were statistically unaffected by the treatment in both groups, though 2 patients in the shunt group developed severe hearing loss (anacusis/70 dB).     

Region-specific changes in GABAA receptor delta subunit mRNA level by tolerance to and withdrawal from pentobarbital

This paper is, aiming at understanding disturbances of and correllation between colchear and vestibular functions in Meniere's disease. Auditory and vestibular functions in 121 Meniere cases (70 males and 51 females, age ranging from 19 to 63 years), diagnosed according to the AAO-HNS criteria, were analysed. The results were as follows: 1)There was positive correlation between semicircular canal paresis and hearing impairment. 2) There was statistically significant positive correlation between hearing impairment and the -SP/AP ratio. 3) There was statistically significant correlation between hearing impairment and glycerin test result, the rate of positive result being higher in those with advanced hearing loss than in those with mild loss. 4) There was correlation between the rate of positive glycerin test result and audiogram configuration. The rate with rising audiogram pattern was higher than with that falling pattern (69.0% vs 33.3%). It was also found that ECochG was far more effective than glycerin test in diagnosing Meniere's disease. The physiologic basis and significance of ECochG and glycerin test in Meniere's disease were discussed.     

Mutations in the COCH gene are a frequent cause of autosomal dominant progressive cochleo-vestibular dysfunction, but not of Meniere's disease

The COCH gene is the only gene identified in man that causes autosomal dominantly inherited hearing loss associated with vestibular dysfunction. The condition is rare and only five mutations have been reported worldwide. All affected families showed a similar progressive hearing loss and vestibular dysfunction. Since Meniere's disease-like symptoms have also been described in some families, it was suggested that COCH mutations might be present in some patients diagnosed with Meniere's disease. In this study, using a Japanese population, we performed a COCH mutation analysis in 23 patients from independent families with autosomal dominant hearing impairment, four of whom reported vestibular symptoms, and also in 20 Meniere's patients. While a new point mutation, A119 T, was found in a patient with autosomal dominant hearing loss and vestibular symptoms, no mutations were found in the Meniere's patients. Like all other previously identified COCH mutations, the mutation identified here is a missense mutation located in the FCH domain of the protein. The current mutation is located in close spatial proximity to W117, in which a mutation (W117R) had previously been associated with autosomal dominant hearing loss. Model building suggests that, like the W117R mutation, the A119 T mutation does not affect the structural integrity of the FCH domain, but may interfere with the interaction with a yet unknown binding partner. We conclude that mutations in the COCH gene are responsible for a significant fraction of patients with autosomal dominantly inherited hearing loss accompanied by vestibular symptoms, but not for dominant hearing loss without vestibular dysfunction, or sporadic Meniere's disease.     

Endoscope-assisted vestibular neurectomy

OBJECTIVE/HYPOTHESIS: In some instances endoscopes offer better visualization than the microscope and frequently allow less invasive surgery. This study was undertaken to determine whether endoscopy is safe and effective during neurectomy of the vestibular nerve. METHOD: Ten patients with intractable unilateral Meniere's disease underwent a retrosigmoid craniotomy for neurectomy of the vestibular nerve. Endoscopy with a Hopkins telescope was used during each procedure to study posterior fossa anatomic relationships and to assist the neurectomy. Preoperative and postoperative audiometric evaluation was performed in all patients undergoing vestibular neurectomy. Nine of these patients had preoperative electronystagmography, and four patients completed postoperative electronystagmography. The 1995 American Academy of Otolaryngology-Head and Neck Surgery's Committee on Hearing and Equilibrium guidelines for the diagnosis and evaluation of therapy in Meniere's disease were used. RESULTS: Complete neurectomy was achieved in all 10 patients. Endoscopy allowed improved identification of the nervus intermedius and the facial, cochlear, and vestibular nerves and adjacent neurovascular relationships without the need for significant retraction of the cerebellum or brainstem. In addition, endoscopic identification of the cleavage plane between the cochlear and vestibular nerves medial to or within the internal auditory canal (n = 3) was not made with the 0-degree endoscope; however, identification was made with the 30- or 70-degree endoscope in all cases. In all patients with Meniere's disease, elimination of the recurrent episodes of vertigo (n = 10) or otolithic crisis of Tumarkin (n = 1) was achieved. CONCLUSIONS: Posterior fossa endoscopy can be performed safely. Endoscope-assisted neurectomy of the vestibular nerve may offer some advantages over standard microsurgery including increased visualization, more complete neurectomy, minimal cerebellar retraction, and a lowered risk of cerebrospinal fluid leakage.     

Vestibular nerve section: long-term follow-up

Vestibular nerve section is considered an effective modality in the treatment of refractory and incapacitating vertigo. Typically nerve section results are described on the basis of short-term follow-up. We have reviewed 41 cases of vestibular nerve section spanning an 18-year period. Although the majority of cases involved classic Meniere's disease, delayed endolymphatic hydrops, vestibular neuritis, and Meniere's syndrome secondary to head trauma were also included. Surgical approaches included translabyrinthine (20 cases), retrolabyrinthine (14 cases), retrosigmoid (six cases), and middle fossa (one case) procedures. Postoperative follow-up time averaged 102 months, with 46% of patients followed for a minimum of 9 years. Results are reported according to standards set forth by the American Academy of Otolaryngology--Head and Neck Surgery. Vertigo was cured or markedly improved in 88% of cases (90% in patients with Meniere's disease) at 18 to 24 months postoperatively. These vertigo results were sustained at the time of latest follow-up. Functional level was also preserved over time despite the development of bilateral symptoms in several cases. The rate of bilateral disease reached 22% of cases. Although vertigo results remained stable, long-term follow-up of successful hearing preservation cases demonstrated deterioration over time. Postoperative continuation of medical treatment is urged to optimize and sustain the vestibular neurectomy result.     

Summating potential and action potential ratio in Meniere's disease before and after treatment

OBJECTIVE: This study aimed to compare the summating potential and action potential ratio (SP:AP) in patients with Meniere's disease before and after various surgical and medical treatments as an indication of change in endolymphatic hydrops to study the progression of Meniere's disease. STUDY DESIGN: The study design was a retrospective case review. SETTING: The study was conducted at an otology-neurotology referral center. PATIENTS: Eighty-eight ears of 84 patients with Meniere's disease received medical treatment in 18 ears and surgical treatments including endolymphatic shunt in 12 ears, streptomycin perfusion of the lateral semicircular canal in 9 ears, streptomycin perfusion of the middle ear in 33 ears, and dexamethasone perfusion of the middle ear in 16 ears. INTERVENTION: Transtympanic electrocochleography (ECoG) was performed in all patients before treatment and 1-57 months after treatment (mean, 13.5 months) with a 2-year interval in 28 patients. MAIN OUTCOME MEASURE: An enlarged SP:AP ratio (> or = 0.40) was used as the diagnostic criterion for endolymphatic hydrops. RESULTS: Overall, an enlarged SP:AP ratio was found in 75% of ears before treatment and 78% after treatment. The SP:AP ratio, when enlarged, remained enlarged in 91% of ears. A nonenlarged SP:AP ratio before treatment became enlarged after treatment in 41% of ears. In American Academy of Otolaryngology-Head and Neck Surgery stage 1 Meniere's disease (pure-tone threshold average < or = 25 dB), an enlarged SP:AP was found in 58% of ears before treatment and 79% after. Twenty-five (89%) of 28 patients followed for 2 years were free of vestibular symptoms after treatment, and in 22 patients (79%), the SP:AP remained enlarged. The distribution of an enlarged SP:AP ratio was associated with the duration of disease (chi-square = 33.5552, p < 0.01). CONCLUSIONS: The development of endolymphatic hydrops, as indicated by an enlarged SP:AP, is part of the progression of Meniere's disease. The longer the duration of the disease, the more likely the SP:AP ratio will be enlarged. These findings indicate that endolymphatic hydrops as detected by ECoG was not reversed in this study by the treatments used. Despite the absence of definitive spells of vertigo in most patients, endolymphatic hydrops as evidenced by an enlarged SP:AP ratio persisted.     

Dexamethasone perfusion of the labyrinth plus intravenous dexamethasone for Ménière's disease

Recent clinical and laboratory evidence indicates that Meniere's disease is an immune-mediated disease. Dexamethasone perfusion of the inner ear through the round window plus intravenous dexamethasone often will stop the dizzy spells, reduce the fullness and low-frequency tinnitus, and sometimes improve the hearing in patients with Meniere's disease. The dexamethasone must act mostly on the endolymphatic sac and, to a lesser extent, on the stria vascularis and spiral ligament, the known targets of immune response in the inner ear, to reduce the endolymphatic hydrops and restore the fluid dynamics of the endolymph. Despite the good results with streptomycin perfusion, the number of patients with further hearing loss is large, so dexamethasone perfusion with intravenous dexamethasone should be tried first. The initial response to dexamethasone perfusion plus intravenous dexamethasone has been very good, with very little risk of further hearing loss, and it holds great promise for the future.     

Surgery for intractable vertigo: Chiang Mai experience

If medical therapy fails (6-12 months or more), careful consideration of surgical therapy should be followed with; the patient's hearing, severity of symptoms, age, and occupation. Cochleosacculotomy is reserved for elderly Meniere's patients with poor health, poor hearing and good vestibular function. Endolymphatic sac shunt should be considered as the first procedure for disabled Meniere's patients with aidable hearing and may also be used in those patients with bilateral Meniere's disease. Retrolabyrinthine vestibular nerve section (RLVNS) is indicated for patients with disabling vertigo and normal or aidable hearing. It could be done for all peripheral vertigo and for failed endolymphatic sac procedure. A destructive procedure, such as labyrinthectomy, should be a procedure of choice in a patient who presents with peripheral incapacitating vertigo and nonserviceable hearing loss in the solely affected ear. Again, patients with failed cochleosacculotomy, endolymphatic shunt then go on to receive either labyrinthectomy or RLVNS, based on residual hearing. To obtain a satisfactory surgical result, the surgeon must be precise in selecting the patient with the right disease at the right time.     

Diagnostic testing for endolymphatic hydrops

The development of a sensitive and specific diagnostic test for endolymphatic hydrops has eluded investigators for over 30 years. The absence of such a test has hampered basic and clinical research into Meniere's disease and related entities. Presently used tests are limited in their applicability because of their low sensitivity and specificity and a poor understanding of the underlying physiologic principles. Despite this, it is generally agreed that some of these studies have merit in selected situations. This article reviews the present state of diagnostic testing for endolymphatic hydrops. The use of nonspecific studies, such as basic audiometry and tests for recruitment, and "specific" studies, such as electrocochleography and dehydration testing, are critically reviewed.     

Neonatal screening for sickle cell disease in the Consorci Sanitari de Mataro. Rationale and first results]

A total of 62 ears of patients with typical Meniere's disease was examined by the furosemide test to detect endolymphatic hydrops. In 95% of the normal control group, the per cent change in the maximum velocity of the slow phase of caloric nystagmus (MVS) after injection of furosemide was under 10%. Therefore, a positive furosemide test was defined as a change in MVS of more than 10%. Thirty-five (56%) of the 62 ears with typical Meniere's disease showed a positive furosemide test. When the affected ears were divided into two groups according to vestibular symptoms, only 11 (38%) of 29 inactive ears were positive while 24 (73%) of 33 active ears were positive. There was a significant difference in the positive rate of the furosemide test between the ears with clinically inactive and active vestibular disease. The per cent canal paresis (CP%) was determined to assess canal excitability and a CP%> 25% was defined as canal paresis. There was no significant difference in the furosemide test positive rate between ears with canal paresis and ears with a normal CP%, although the former tended to show a greater MVS change. The response to the furosemide test showed no relationship to the results of pure tone audiometry. In conclusion, the furosemide test appears to indicate the vestibular status in various stages of Meniere's disease.     

More on ''the invisible disability''

20-year experience with 220 cases of cochleovestibular disorders treated with betaserk shows high efficacy of this drug in the above patients, especially at initial stages of Meniere's disease. Betaserk is recommended for wide outpatient practice.     

Treatment of intractable Menière's disease with intratympanic gentamicin: review of the University of Ottawa experience

OBJECTIVE: Intractable Meniere's disease has traditionally been treated surgically, with either labyrinthectomy, vestibular nerve section, or endolymphatic sac procedures. Another option is the use of intratympanic gentamicin to effect a 'gentamicin labyrinthectomy.' Nedzelski and coworkers have previously reported an 83% complete elimination and 17% substantial reduction in vertigo using this method. METHOD: We retrospectively reviewed 21 patients treated at our centre with intratympanic gentamicin between 1991 and 1995, all of whom fulfilled the criteria for reporting results in Meniere's therapy described in the American Association of Otolaryngology Committee on Hearing and Equilibrium 1995 guidelines. Our patients are presented using these guidelines, specifically examining four criteria: frequency of vertigo, word recognition, functional level, and hearing threshold. RESULTS: At 2-year follow-up, 17 of 21 patients (80.9%) had complete elimination of vertigo, with 3 of 21 (14.3%) reporting a 60 to 99% reduction in frequency. Nineteen of 21 patients (90.5%) described themselves as having no impairment secondary to dizziness. Average hearing thresholds and word-recognition scores appear to have both worsened after gentamicin therapy. CONCLUSION: Intratympanic gentamicin therapy for vertigo in Meniere's disease was shown to be an effective treatment choice, as shown by our results. However, with the reduction of average hearing thresholds and word-recognition scores, patients should be advised of these possible complications as part of informed consent.     

The effect of triple pelvic osteotomy on the articular contact area of the hip joint in dysplastic dogs: an in vitro experimental study

This study compares the frequency of signs and symptoms from the cervical spine in 24 patients diagnosed with Meniere's disease and 24 control subjects from a population sample. From a previous controlled comparative study concerning signs and symptoms of craniomandibular disorders, 24 patients diagnosed with Meniere's disease (10 males and 14 females) and their 24 matched control subjects participated in this investigation on the state of the cervical spine. Symptoms of cervical spine disorders, such as head and neck/shoulder pain, were all significantly more frequent in the patient group than in the control group. Most of the patients (75%) reported a strong association between head neck movements in the atlanto-occipital and atlanto-axial joints and triggered attacks of vertigo. Also, 29% of the patients could influence their tinnitus by mandibular movements. Signs of cervical spine disorders, such as limitations in side-bending and rotation movements, were significantly more frequent in the patient group than in the control group. Tenderness to palpation of the transverse processes of the atlas and the axis, the upper and middle trapezius, and the levator scapulae muscle were also significantly more frequent in the patient group. The study shows a much higher prevalence of signs and symptoms of cervical spine disorders in patients diagnosed with Meniere's disease compared with control subjects from the general population.