12
Meniere’s Disease: Diagnosis and Management
First described by Prosper Meniere in 1861, the condition that bears his name has manifested itself as a common problem afflicting patients throughout the world.1 Classically consisting of a triad of symptoms that include episodic vertigo, fluctuating hearing loss, and tinnitus, Meniere’s disease occurs with an incidence of 45,500 to over 90,000 new cases each year.2 The most afflicted age group are the most productive years of life, the fourth through the sixth decades, with a slight female preponderance. Meniere’s disease, though, is also the great masquerader, complicating the accurate diagnosis of this condition. Furthermore, the severity of symptoms and the level of rehabilitation experienced by the patient vary widely, complicating the optimal treatment. Thus the adage the only thing that’s predictable about Meniere’s disease is its unpredictability holds true.
This chapter reviews the characteristics of the patient suffering from Meniere’s disease, the pathophysiology, the diagnostic workup, and the senior author’s (RJW) approach in treatment.
■ Pathogenesis
Although a comprehensive discussion regarding the pathogenesis and pathophysiology of Meniere’s disease is beyond the scope of this chapter, we will discuss the basic theories. The etiology of Meniere’s disease is unknown, but the common histopathologic correlate is hydrops (first confirmed by Hallpike in 1938) of the endolymph-containing spaces of the inner ear.3, 4 Animal studies where the endolymphatic sac was destroyed or blocked produced a similar endolymphatic hydropic state that is seen in temporal bone studies of patients with Meniere’s disease.5 This begs the question of whether this hydropic state is the result of overproduction of endolymph or inadequate resorption. Hebbar and colleagues suggest that endolymphatic hydrops results from inadequate resorption of endolymph from their anatomical studies, which showed that patients with Meniere’s disease had reductions in tubular specializations of the lining of the endolymphatic duct and sac.6 Shambaugh and Gussen have postulated that hydrops resulted from inadequate resorption of endolymph as a result of vascular insufficiency of the endolymphatic sac.7, 8 Others have theorized that saccular damage results from an autoimmune or infectious phenomenon resulting in perisaccular inflammation, which ultimately results in perisaccular fibrosis with consequent reduced endolymph resorption. This theory is based on the presence of immune complexes and viral particles within the serum and the endolymph of patients with Meniere’s disease. Yazawa and Kitahara have corroborated these hypotheses with temporal bone studies showing perisaccular fibrosis and ischemic changes.9 Wackym and Sando, however, challenge the presence of perisaccular fibrosis in their review of 18 temporal bones from patients with premortem Meniere’s disease as compared with 19 normal temporal bones.10
Regardless of the cause of the hydropic state, it is postulated that this distention of the endolymphatic space ultimately results in membrane rupture within the inner ear. What results is endolymph mixing with perilymph. This has been corroborated by temporal bone studies.11– 16 Vertigo then ensues, and damage to the cochlear apparatus progressively impairs hearing. Because endolymphatic hydrops has been found in those without symptoms of Meniere’s disease, it is likely that the membrane rupture is what differentiates those with asymptomatic hydrops from those with Meniere’s syndrome.17 At this time, there is no absolute diagnostic test to confirm hydrops; however, there is a promise of newer imaging methods yet to come. Furthermore, although the theories forwarded by previous work are attractive, it must be clear that the true pathophysiology of Meniere’s disease is far from clear.
■ Clinical Presentation
History is most valuable in the assessment of the patient with Meniere’s disease, for early in the process, diagnostic tests are not conclusive. Furthermore, the clinician rarely sees the patient during an acute attack. Between attacks, the physical examination yields little. Thus an accurate and thorough history is imperative. Meniere’s disease is most often seen during middle age.18 There is a slight predisposition toward females (1.3:1) whereas no racial preponderance is seen.19 Genetic predisposition is likely because Morrison has given credible evidence that Meniere’s can be inherited in ~20% of cases.20
The patient will classically report one or more episodes consisting of new onset of fluctuating hearing loss, initially, or worsening of already present tinnitus and unilateral aural fullness, culminated by disabling rotary vertigo. The onset of vertigo is often sudden, without warning, and accompanied by nausea and vomiting. Often, the patient will also experience sound distortion, diplacusis, and recruitment. Between attacks, the patient can be completely asymptomatic or have a residual sensation of dysequilibrium.
These attacks are variable in presentation. Most patients will report that tinnitus, hearing loss, and aural fullness continue in severity with the vertigo, with some improvement over time as vertigo resolves. Spontaneous remission of vertigo does occur, but once the diagnosis is made, these remissions may take 10 years in our experience. Two subvariants of Meniere’s disease exist. Lermoyez described some attacks where hearing loss improves with the onset of vertigo.21 Rarely, some patients will experience crises of Tumarkin, unexplained falls not associated with loss of conciousness.22 These patients may or may not experience vertigo with these falls. Other variations have also been described, including cochlear Meniere’s disease, where only the auditory fluctuations are seen without vertigo, and vestibular Meniere’s disease, where only episodic vertigo is observed. To assist in identifying those patients most likely to have Meniere’s disease, the American Academy of Otolaryngology -Head and Neck Surgery (AAO-HNS) Committee on Hearing and Equilibrium has developed a diagnostic guideline as seen in Table 12–1.23 Though most patients display unilateral disease, 30 to 40% will ultimately develop bilateral disease.
Certain Meniere’s disease |
Definite Meniere’s disease, plus histopathologic confirmation |
Definite Meniere’s disease |
Two or more definitive spontaneous episodes of vertigo 20 minutes or longer Audiometrically documented hearing loss on at least one occasion Tinnitus or aural fullness in the treated ear Other causes excluded |
Probable Meniere’s disease |
One definitive episode of vertigo Audiometrically documented hearing loss on at least one occasion Tinnitus or aural fullness in the treated ear Other causes excluded |
Possible Meniere’s disease |
Episodic vertigo of the Meniere type without documented hearing loss; or Sensorineural hearing loss, fluctuating or fixed, with dysequilibrium but without definitive episodes Other causes excluded |
(Source: Data from Committee on Hearing and Equilibrium guidelines for the diagnosis and evaluation of therapy in Meniere’s disease. American Academy of Otolaryngology Head and Neck Foundation, Inc. Otolaryngol Head Neck Surg 1995;113:18JJ185.)
■ Diagnostic Evaluation
Audiometry
Patients with Meniere’s disease are classically described as having low-frequency sensorineural hearing loss, though Friberg et al have reported a flat pure-tone audiogram in 21% at initial audiogram.24 Further testing will often reveal diplacusis and recruitment. Fluctuations in pure-tone thresholds can be demonstrated, although the natural history is continued deterioration over several years, with few becoming profoundly deaf (1-2%).25
Electronystagmography
Electronystagmography (ENG) allows the localization of the pathological process to the peripheral end-organ and rules out central causes of the patient’s symptoms. It will also allow the determination of the ear affected by Meniere’s disease, with the caveat that ENG testing can be normal early in the disease process.26 As found by Dobie et al, only 49% of patients with Meniere’s disease will display unilateral weakness on caloric stimulation, whereas 25% will show normal findings.26
Electrocochleography
Electrocochleography (EcoG) is used to identify a hydropic state within the labyrinth. As reported by Coats, Morrison et al, and Ferraro et al, a prolonged summating potential and an elevated summating potential:compound action potential ratio is indicative of endolymphatic hydrops.27–29 Despite these assertions, only 62% of patients with Meniere’s disease display an elevated summating potential:compound action potential ratio compared with 21% of controls.30 Additionally, Merchant et al have pointed out that there are temporal bone studies of cases of idiopathic hydrops with intact sensory and neural structure who do have Meniere’s syndrome during life.31
Differential Diagnosis
Meniere’s disease has been called the great masquerader because many clinical entities present with similar histories, signs, and symptoms. A variety of conditions can produce endolymphatic hydrops, so a thorough history is crucial. For example, any history of syphilis exposure is important because tertiary syphilis and congenital syphilis can present symptoms that are indistinguishable from Meniere’s disease. Furthermore, any history of uveitis or visual changes is an important clue to the possibility of Cogan’s syndrome. A history of head trauma with accompanying hearing loss is important to consider because the patient may be presenting delayed endolymphatic hydrops. Also, one must not neglect the possibility of a perilymphatic fistula, especially if there is a history of head trauma, barotraumas, or a sensation of an audible pop. Any patient with chronic ear disease or physical findings of cholesteatoma must be evaluated for the possibility of a labyrinthine fistula. Furthermore, the possibility of a serous labyrinthitis must also be entertained if the patient has either chronic otitis media or acute otitis media.
Meniere’s disease is often confused with other causes of vertigo. For example, after an episode of acute vestibular neuritis, prior to vestibular compensation, patients will have a sense of dysequilibrium with multiple, lesser episodes of vertigo. These patients will have no auditory symptoms and the subsequent episodes of vertigo will be reported in lesser severity than the initial attack, differentiating this entity from Meniere’s disease.
Benign paroxysmal positional vertigo (BPPV) can also be confused with Meniere’s disease. These patients will give a history of vertigo lasting a short time (several seconds to several minutes) that is associated with specific movements such as getting out of bed, bending over, or looking up. One must separate the period of actual vertigo from the dysequilibrium and nausea that may follow because these symptoms may last several hours. There are no auditory components to the patient’s history. A positive Dix-Hallpike maneuver is diagnostic. Though BPPV may exist in the patient, one must not discount the possibility that both entities exist in the same patient.
In some patients, episodes of vertigo may precede a migraine headache. This may or may not accompany visual aura. These patients are more likely to suffer from a vestibular variant of migrainous headaches, and the pharmacological treatment of migraine headaches will improve the vertigo complaints.
■ Treatment
The treatment of any ailment should always begin with education of the patient. Often, patients will initially present with information regarding the various causes of dizziness. With the glut of information that is present on the Internet, clinicians must realize their role as educators who provide knowledge in addition to simply information. This education should begin with an explanation of Meniere’s disease, the expected course of the symptoms, and the treatment options. What will result will be greater cooperation and a greater sense of empowerment on the part of the patient. Patients are often asked to keep a calendar of events of their symptoms and see the treating physician at least four times a year to assess the need for change.
In treating Meniere’s disease, we take a stepped approach utilizing a clinical ladder progressing from a conservative approach considering the symptoms associated with Meniere’s disease. Table 12–2 lists some of the symptoms and treatment options for managing Meniere’s disease symptoms. Treatment begins first with medical management. The majority of our patients achieve satisfactory control of their symptoms with diuretics and diazepam. Surgical options are considered only if the patient experiences unacceptable results with this approach. With surgical options we prefer to begin with nonablative procedures but take into account the patient’s lifestyle, livelihood, and preferences.
Medical Management
Dietary and Lifestyle Changes
All patients are advised to abstain from alcohol, tobacco, caffeine, and chocolate. Furthermore, we ask patients to follow a low salt diet (less than 3000 mg of sodium daily). We specifically warn patients regarding situations where a large salt load may be present including fast foods and canned goods. When possible, strategies to avoid stress, or at least adaptive methodologies, are mentioned.
Problem | Prevention/Treatment |
|---|---|
Diagnosis | 1. Thorough history regarding symptoms experienced and exclusion of known causes of the Meniere’s syndrome |
Hearing loss | 1. A burst of systemic steroids |
Tinnitus | 1. Masking strategies |
Vertigo |
