Meniere Disease (Idiopathic Endolymphatic Hydrops)

Background

Ménière disease is a disorder of the inner ear that is also known as idiopathic endolymphatic hydrops. Endolymphatic hydrops refers to a condition of increased hydraulic pressure within the inner ear endolymphatic system. Excess pressure accumulation in the endolymph can cause a tetrad of symptoms: (1) fluctuating hearing loss, (2) occasional episodic vertigo (usually a spinning sensation, sometimes violent), (3) tinnitus or ringing in the ears (usually low-tone roaring), and (4) aural fullness (eg, pressure, discomfort, fullness sensation in the ears).

The term endolymphatic hydrops is often used synonymously with Ménière disease and Ménière syndrome, both of which are both believed to result from increased pressure within the endolymphatic system. However, Ménière disease is idiopathic by definition, whereas Ménière syndrome can occur secondary to various processes interfering with normal production or resorption of endolymph (eg, endocrine abnormalities, trauma, electrolyte imbalance, autoimmune dysfunction, medications, parasitic infections, hyperlipidemia). With the growing understanding of the pathophysiology and disease processes involved with Ménière disease a re-evaluation and possible redefinition of this condition are well underway.^[1]

The distinction in nomenclature is analogous to that applied to Bell palsy. When the source of facial paralysis is known, Bell palsy is not the diagnosis. Similarly, when the cause of vertigo is known, Ménière disease is not the diagnosis. In other words, Ménière syndrome is endolymphatic hydrops caused by a specific condition, and Ménière disease is endolymphatic hydrops of unknown etiology (ie, idiopathic endolymphatic hydrops).

Evaluation and management of dizziness and vertigo can be one of the most difficult medical tasks. Sources of imbalance can range from simple conditions (eg, dehydration) to serious conditions (eg, brain tumors). Central nervous system (CNS) problems must be distinguished from circulation anomalies, chemical and hormonal imbalances, and peripheral inner ear disorders. Often, this distinction is not clear. (For related information, see Dizziness, Vertigo, and Imbalance.)

Medical therapy can be directed toward treatment of the actual symptoms of the acute attack or directed toward prophylactic prevention of the attacks. If endolymphatic hydrops is attributable to a given disease process—that is, if it is Ménière syndrome rather than Ménière disease—the first-line management is diagnosis and treatment of the primary disease (eg, thyroid disease). Surgical therapy for Ménière disease is reserved for medical treatment failures and is otherwise controversial.

Go to Surgical Treatment of Meniere Disease for complete information on this topic.

• References

Anatomy

The relevant anatomy centers on the petrous bone and the inner ear. The ear is divided into 3 sections: external, middle, and inner. The external ear consists of the auricle, external ear canal, and tympanic membrane. The tympanic membrane separates the external ear from the structures of the middle ear. The middle ear is an air-containing space that houses the 3 hearing bones: the malleus, the incus, and the stapes. The inner ear is completely encased in bone and consists of the cochlear-vestibular apparatus and its associated nerves.

The cochlear-vestibular apparatus is a complex structure arranged in a complex yet elegant spatial orientation. Because it is completely encased in bone, this structure is housed in a series of winding tunnels and interconnecting spaces. The mazelike orientation of these tunnels is appropriately named the labyrinth. The bone that encases it is the bony labyrinth.

The cochlea is a snail-shaped chamber that houses the organ of Corti. It is responsible for translating mechanical vibrations into electrical impulses and sending them to the brain through the cochlear nerve.

The vestibular system consists of a large chamber (ie, the vestibule) from which 3 semicircular canals protrude. Within the vestibule, 2 sensors (the utricle and the saccule), detect linear acceleration, and the semicircular canals detect rotational movements in the 3 planes of rotation. The vestibular apparatus gives off 2 nerves: the superior and the inferior vestibular nerves. Together with the cochlear and facial nerves, the vestibular nerves travel through the internal auditory canal to the cerebellopontine angle.

The cochlea and the vestibular system are joined in the middle and share a dual-chambered hydraulic system. These hydraulic chambers are bathed by 2 fluids: endolymph and perilymph. Endolymph is produced primarily by the stria vascularis in the cochlea and also by the planum semilunatum and the dark cells in the vestibular labyrinth.^[2] Perilymph is protein-poor extracellular fluid. A membrane (ie, the membranous labyrinth) separates the fluids and completely surrounds and contains the endolymph.

The system may be visualized as a water balloon floating in a pool. In this analogy, the water inside the balloon is the endolymph, and the balloon itself is the membranous labyrinth that contains the endolymph. The surrounding pool water is the perilymph, which supports the delicate nerve tissues of the membranous labyrinth. The walls of the pool represent the limits of the bony labyrinth space, and the ground encasing the pool is the bone that encases the labyrinthine space.

The endolymphatic sac is a reservoir pouch that resides on the posterior surface of the petrous bone against the posterior fossa dura. It is connected via the vestibular duct to drain into the endolymphatic space of the cochlea.

Endolymphatic flow has been described as following a “lake-river-pond” model. The endolymph flows from the endolymphatic fluid space (the lake) through the vestibular aqueduct (the river) to the endolymphatic sac (the pond).^[3] If there is obstruction, then endolymphatic hydrops will occur.

• References

Pathophysiology

The exact pathophysiology of Ménière disease is controversial. The underlying mechanism is believed to be distortion of the membranous labyrinth resulting from overaccumulation of endolymph. Some authors have questioned whether endolymphatic hydrops is actually a marker of disease rather than a cause. A study looking at temporal bones found that all patients with Ménière’s disease had hydrops in at least 1 ear but that hydrops was also found in patients who exhibited no signs of the disease.^[4]

The endolymph and perilymph (ie, fluids that fill the chambers of the inner ear) are separated by thin membranes that house the neural apparatus of hearing and balance. Fluctuations in pressure stress these nerve-rich membranes, causing hearing disturbance, tinnitus (see the image below), vertigo, imbalance, and a pressure sensation in the ear.

View Image

Tinnitus model. Two phenomena in auditory cortex are associated with peripheral deafferentation: (1) hyperactivity in lesion projection zone and (2) i....

Attacks of hydrops probably are caused by an increase in endolymphatic pressure, which, in turn, causes a break in the membrane that separates the perilymph (potassium-poor extracellular fluid) from the endolymph (potassium-rich intracellular fluid). The resultant chemical mixture bathes the vestibular nerve receptors, leading to a depolarization blockade and transient loss of function. The sudden change in the rate of vestibular nerve firing creates an acute vestibular imbalance (ie, vertigo).

The physical distention caused by increased endolymphatic pressure also leads to a mechanical disturbance of the auditory and otolithic organs. Because the utricle and saccule are responsible for linear and translational motion detection (as opposed to angular and rotational acceleration), irritation of these organs may produce nonrotational vestibular symptoms.

This physical distention causes mechanical disturbance of the organ of Corti as well. Distortion of the basilar membrane and the inner and outer hair cells may cause hearing loss and/or tinnitus. Since the apex of the cochlea is wound much tighter than the base, the apex is more sensitive to pressure changes than the base. This explains why hydrops preferentially affects low frequencies (at the apex) as opposed to high frequencies (at the relatively wider base). Symptoms improve after the membrane is repaired as sodium and potassium concentrations revert to normal.

Various extrinsic mechanisms are thought to contribute to the development of endolymphatic hydrops, including infection, trauma, and allergens

• References

Etiology

By definition, Ménière disease is idiopathic. In other words, if the cause is known, the disease process can no longer be called Ménière disease. However, because the root of the problem is elevated endolymphatic pressure, it is worthwhile to consider other causes of endolymphatic hydrops. Ménière disease must be distinguished from these causes.

Disorders that may give rise to elevated endolymphatic pressure include metabolic disturbances, hormonal imbalance, trauma, and various infections (eg, otosyphilis and Cogan’s syndrome [interstitial keratitis]).^{[5, 6]}

Autoimmune diseases, such as lupus and rheumatoid arthritis, may cause an inflammatory response within the labyrinth. An autoimmune etiology was postulated after there was found to be an association with the presence of thyroid autoantibodies in patients with Ménière disease.^{[7, 8]}

In addition, allergy has been implicated in many patients with difficult-to-treat Ménière disease. Food triggers are also important factors in the generation of hydrops.

• References

Epidemiology

In the United States, a prevalence of 1,000 cases of endolymphatic hydrops per 100,000 population is a reasonable approximation, though it is probably an underestimate. Familial predisposition may be a factor, since half of patients have a significant family history.^[9]

The reported prevalence of Ménière disease (ie, idiopathic endolymphatic hydrops) varies widely, from 15 per 100,000 in the United States to 157 per 100,000 in the United Kingdom.^[10] This difference in prevalence based on geographic area is likely due to reporting biases and not geographic patterns of disease. Bilateral disease is found in 10% of patients with Ménière disease at initial diagnosis; with disease progression, it may be found in more than 40%.^[11]

Ménière disease can be seen at almost all ages: it has been described in children as young as 4 years and in elderly persons older than 90 years.^[3] The typical onset begins at early to middle adulthood. The peak incidence of Ménière’s disease is in the 40- to 60-year-old age group.^[10] The mean age among treatment groups in some studies ranged from 49-67 years.

Ménière disease appears to be more common in females than in males, with reported ratios ranging from 1.3:1^[10] to 1.8:1. These figures may reflect reporting bias—that is, they may in part be the result of more females seeking treatment.The disease primarily affects whites,^[12] although this finding too may reflect reporting bias.^[13]  The female predilection of Ménière disease is shared with migraine headache and, in fact, there is a growing body of evidence that Ménière disease and migraine headache may be related and/or different spectrums of the same disease.^[14]

• References

Prognosis

Patient presentation and progression of Ménière disease vary widely. The disease can be classified into several stages of progression. Early stages involve cochlear hydrops, which proceeds to affect the vestibular system. Ménière disease is most bothersome during these early stages.

As patients progress to later stages, the hydrops fills the vestibule so completely that no further room is available for pressure fluctuation and the vertigo spells disappear. The acute attacks are replaced by constant imbalance and progressive hearing loss.

The prognosis of patients with Ménière disease varies. Periods of remission punctuated by exacerbations of symptoms are typical.^[15] Some patients have minimal symptoms, whereas others have severe attacks. Episodes may occur as infrequently as once or twice a year or they may occur on a regular basis.

The pattern of exacerbation and remission makes evaluation of treatment and prognosis difficult. In general, the patient’s condition tends to spontaneously stabilize over time. Ménière disease is said to “burn out” over time. The spontaneous remission rate is high: over 50% within 2 years and over 70% after 8 years.^[10] This spontaneous stabilization comes at a price, however: many patients are left with poor balance and poor hearing.

Most of the remaining patients (ie, those whose disease does not spontaneously stabilize) are well managed with medications. Surgical treatment is required for 5-10% of patients.

Ménière disease is not directly associated with mortality; however, it is associated with drop attacks, which could lead to accidental trauma resulting in morbidity or mortality. Failure to warn patients of the possibility of drop attacks, which could result in injury, is a pitfall.

The main morbidity associated with Ménière disease is the debilitating nature of vertigo and the progressive and possibly permanent loss of hearing. In a Finnish study using a questionnaire, 22% of respondents listed problems with mobility and 19% listed mental effects of their illness.^[16]

• References

Patient Education

Proper education in terms of dietary control and avoidance techniques is helpful. Vestibular rehabilitation can be useful in teaching patients to cope with the vertigo and imbalance. Patients should be warned of the possibility of falls.

Patients should be instructed that if their symptoms significantly worsen or if they develop any new symptoms suggestive of another disease process they should return immediately to the emergency department for reevaluation.

For patient education resources, see the Brain and Nervous System Center and the Ear, Nose, and Throat Center, as well as Dizziness, Ménière Disease, and Tinnitus.

• References

History

The American Academy of Otolaryngology–Head and Neck Surgery Foundation (AAO-HNS) Committee on Hearing and Equilibrium published guidelines on the clinical diagnosis of Ménière disease in 1972, 1985, and 1995. According to these guidelines, Ménière disease is defined as “recurrent, spontaneous episodic vertigo; hearing loss; aural fullness; and tinnitus. Either tinnitus or aural fullness (or both) must be present on the affected side to make the diagnosis.”^[17]

Accordingly, the typical history involves episodic attacks of true whirling vertigo, which usually are preceded by a variable sense of ear pressure and fullness, decreased hearing, and a low-tone roaring tinnitus. Fewer than one third of patients present with all of the diagnostic components of the disease at onset. Vertigo is the most common initial component, with additional components appearing after a delay of months to years.^{[13, 18]}

Vertigo

Vertigo is a subjective sensation of motion while motionless. Horizontal or rotatory nystagmus is always present during vertiginous attacks.^[17] The vertiginous attacks may last from minutes to hours and often are associated with severe nausea and vomiting. At least 2 definitive episodes of vertigo of at least 20 minutes duration must have occurred to make the diagnosis.^[17] In 10% of patients with the symptom of vertigo, Ménière disease is the cause.^[19]

Acute attacks of vertigo may be accompanied with sudden falls without loss of consciousness. These are termed crises of Tumarkin or drop attacks.^[20] Most studies find the incidence of drop attacks to be less than 10%. In one case series, self-reporting of drop attacks was 72% among patients with diagnosis of Ménière disease.^[21]

After the acute attack, patients generally feel tired, unsteady, and nauseated for hours to days. The timing and frequency of attacks are variable. Some patients can regularly predict an attack while others note a completely random pattern. Attacks may be linked to dietary triggers, the menstrual cycle, or psychosocial stresses.

Between episodes, some patients are completely symptom free. Many notice progressive deterioration of hearing and balance function with each successive attack.

Hearing loss

Sensorineural hearing loss must be documented audiometrically in the affected ear at least once during the course of the disease. There may be fluctuation in the degree of hearing loss superimposed on a gradual decrement in function. The hearing loss primarily affects low frequencies.

Tinnitus

Tinnitus is often nonpulsatile and may be described as whistling, although the classic description is that of low-tone, ocean-like roaring. It may be continuous or intermittent, usually corresponding to the loss of hearing during the attack.

• References

Physical Examination

Examination results vary, depending upon the phase of disease. During remission, physical examination findings may be completely normal, particularly if the patient is symptom free.

During an acute attack, the patient has severe vertigo. Patients are often in significant distress. Many present to the physician’s office clutching a bucket and towel with signs of recent vomiting. Patients are sometimes diaphoretic and pale. Vital signs may show elevated blood pressure, pulse, and respiration. Significant spontaneous nystagmus may be present.

Otoscopy findings are usually normal, although pneumo-otoscopy of the affected ear may elicit symptoms or cause nystagmus. The Romberg test and gait testing may show some instability. The Fukuda marching step test may show significant deviation (if the patient can stand with closed eyes). Hearing usually is diminished on gross examination.

A complete neurologic examination is necessary to differentiate Ménière’s disease from other conditions. New-onset vertigo might be an early sign of stroke, migraine, or brainstem compression that may require emergent evaluation and care.

Evaluation of vertigo

The Dix-Hallpike positional test (also known as the Nylen-Bárány maneuver) is performed.^[22] A positive test result may be indicates coexisting benign positional vertigo. The Dix Hallpike test is performed as described below.

The patient is positioned in the middle of the table so that the head extends past the head of the bed when he or she is supine. The patient is then rapidly moved backward so that the head hangs over the edge, and the eyes are observed for evidence of nystagmus. If no nystagmus is observed over a 20-second period, the patient is returned to the upright position. The next step is to bring the patient rapidly to the head-right supine position, again looking for nystagmus. The maneuver is then repeated for the head-left supine position.

Any nystagmus or symptoms, as well as the position the head was in when these symptoms or signs were elicited, should be noted. Nystagmus typically has a latency of 2-5 seconds. Nystagmus and vertigo associated with peripheral causes such as Ménière disease should be fatigable. Central lesions should have no latency and do not fatigue.

If classic findings of benign paroxysmal positional vertigo are found during Dix-Hallpike testing, then canalith-repositioning procedures may be performed.^[23] Care should be taken to ask about preexisting spine issues and/or neck issues before performing the Dix Hallpike test in order to prevent injury.

The Romberg test generally shows significant instability and worsening during acute attacks when the eyes are closed.

The Hennebert sign is nystagmus caused by positive and negative pressure in the external auditory canal.^[10]

The Tullio phenomenon is sound-induced vertigo, nystagmus, or both.^[24] It is historically associated with syphilis but has been described in Ménière disease.

Evaluation of hearing loss

Gross evaluation of the patient’s hearing can be performed by gently rubbing the examiner’s fingers near the patient’s ears.

The Rinne test is performed with a 512-MHz tuning fork. It usually indicates that air conduction remains better than bone conduction.

The Weber test is also performed with a 512-MHz tuning fork. Normally, sound should be heard equally on both sides. With middle ear disease or blockage of the external auditory canal, or any other types of conductive hearing loss, the sound is more pronounced on the affected side. The tuning fork is said to “lateralize” to the affected side in conductive loss. With cochlear nerve dysfunction, the sound is more pronounced on the unaffected side (the usual finding in these patients). The tuning fork is said to lateralize to the unaffected side (the better hearing ear) in sensorineural loss.

Audiologic testing is more accurate than either of these tests (see Workup).

• References

Complications

Complications of Ménière disease may include the following:

• Injury due to falls
• Anxiety regarding symptoms
• Accidents due to vertigo spells
• Disability due to unpredictable vertigo
• Progressive imbalance and deafness
• Intractable tinnitus

• References

Approach Considerations

Laboratory tests, though not specific for Ménière disease, should be directed at differentiating the disease from other causes on the basis of associated symptoms. More extensive testing is typically reserved for outpatient or inpatient workup and is not performed in the emergency department (ED), including the following otologic tests:

• Audiometry
• Brainstem auditory evoked potentials
• Electrocochleography (ECOG)
• Otoscopy
• Caloric testing/electronystagmography (ENG)

A patient with a history classic for Ménière disease normally does not need imaging studies performed. If there is concern about the presence of other intracranial disease processes, then magnetic resonance imaging (MRI) or computed tomography (CT) can be obtained.

• References

Laboratory Studies

No blood test is specific for Ménière disease. However, the following studies may be ordered to exclude obvious metabolic disturbances, infections, or hormonal imbalances:

• Thyroid-stimulating hormone (TSH), T4, and T3 to rule out hyperthyroidism and hypothyroidism
• Glucose level to rule out diabetes
• Erythrocyte sedimentation rate (ESR) and antinuclear antibody (ANA) test to rule out autoimmune disorders
• Urinalysis to rule out proteinuria and hematuria and indicators of otorenal syndrome
• Complete blood count (CBC) to rule out anemia and leukemia
• Electrolyte levels to rule out salt/water imbalance
• Venereal Disease Research Laboratory test (VDRL) and fluorescent treponemal antibody (FTA-ABS) to rule out neurosyphilis and Lyme disease
• Allergy testing for allergy-mediated Ménière syndrome
• C-reactive protein (CRP)

• References

MRI and CT Scanning

Although usually unnecessary when the patient has a classic history indicative of Ménière disease (MD), MRI or CT may be useful when it is deemed important to identify or exclude other potential disease processes.

MRI of the brain should be done to rule out abnormal anatomy or mass lesions. Specifically, acoustic neuromas or other cerebellopontine angle lesions are sought. Other lesions, such as multiple sclerosis or Arnold-Chiari malformations, also can be ruled out.^[25] Note that mass lesions rarely are found but are important to exclude.

Using 3-dimensional fluid-attenuated inversion recovery MRI (3D-FLAIR MRI), quantitative assessments of endolymphatic hydrops (EH) were found to correlate with the severity of hearing impairment in patients with Ménière disease. In this study, 41 ears were analyzed in 21 subjects (12 ears with MD, 29 without MD). EH was better evaluated on 3D maximum intensity projections (MIPs) than on 2D images.^[26]

In another FLAIR study, delayed 3D FLAIR and fused 3D FLAIR-CISS (constructive interference steady state) color map images of the inner ears after intravenous contrast administration were found to be potentially useful diagnostic tools in the evaluation of patients with suspected Ménière disease. The gray-scale 3D FLAIR images demonstrated 68.2% sensitivity and 97.4% specificity, and the fused color map images demonstrated 85.0% sensitivity and 88.9% specificity in the identification of endolymphatic hydrops in 10 patients with MD and 5 controls.^[27]

CT scans should be normal. They are obtained to detect possible dehiscences of the semicircular canals, congenital abnormalities, widened cochlear and vestibular aqueducts, and subarachnoid hemorrhage. Whereas CT scans are useful at imaging the anatomy of temporal bone structures, specific findings and their association with Ménière disease remain subject to debate.^[28]

• References

Audiometry

Audiometry is particularly helpful for documenting present hearing acuity and detecting future change. In any given patient, the audiogram may have a broad spectrum of results that ranges from normal hearing to profound hearing loss, reflecting the fluctuating nature of the impairment. From patient to patient, there is also a wide range of different types of hearing loss.

The patient may not notice a loss at specific frequencies. Low-frequency or mixed low- and high-frequency insufficiency may be observed. Typically, however, the lower frequencies are affected more severely. This is due to preferential sensitivity of the apex to the hydrops.

Multiple hearing tests, which document fluctuating hearing loss, are helpful in diagnosing Ménière.

• References

Electrocochleography

ECOG is an electrophysiological test that reflects elevation of inner ear pressure. Specifically, it detects distention of the basilar membrane of the inner ear. This distortion is presumably due to elevated endolymph pressure associated with hydrops. The pressure may cause the membranes to tear and the inner ear to misfire, causing vertigo.

ECOG measures the ratio of the summating potential (probably from the movement of the basilar membrane) and the nerve action potential in response to auditory stimuli. Hydrops (elevated pressure) is suggested when this ratio is greater than 35%. The test is most accurate when Ménière disease is active.

• References

Electronystagmography

ENG is a test of inner ear function (particularly the horizontal semicircular canals). The test determines inner ear responsiveness to movement and caloric stimulation. It tests central and peripheral function and can help localize the site of the lesion.

Administer the test when the patient has an empty stomach and after discontinuing meclizine (Antivert), antihistamines, and sedatives for 2 weeks. These drugs may alter test results.

The caloric portion of the test is performed by “irrigating” the ear with warm air and then cold air, with the patient in a supine position. The temperature differential causes the fluid within the horizontal semicircular canal to move, triggering a nystagmus response. The response on one side is compared with the opposite side. As with any reflex, one would expect equal reactions on each side. Usually, anything that would cause a weakened response would be considered pathological.

Typically, endolymphatic hydrops causes a reduced vestibular response in the affected ear, although response may be paradoxically increased secondary to an irritative lesion. The patient may feel dizzy or nauseated.

The direction of the spontaneous nystagmus during or after an attack of Ménière disease is not always a reliable indicator of the site of the lesion. In general, the nystagmus points away from the affected ear because Ménière's disease typically weakens the vestibular response in the affected ear. However, an irritative phase may occur during the attack (fast phases directed toward the involved ear), followed by a paretic phase (fast phases directed toward opposite ear). Since the examiner may not know exactly what phase the patient is in, it is difficult to definitively determine this side of lesion.

• References

Approach Considerations

Medical therapy can be directed toward treatment of the actual symptoms of the acute attack or directed toward prophylactic prevention of the attacks. Most care in the emergency department (ED) is based on symptomatic relief of the clinical findings.

Aside from acute control of vertigo and associated effects (eg, dehydration from protracted vomiting), inpatient care is generally unnecessary. Patients with Ménière disease require admission only if the symptoms are severe and refractory to medical management.

If endolymphatic hydrops is attributable to a given disease process—that is, if it is Ménière syndrome rather than Ménière disease—the first-line management is diagnosis and treatment of the primary disease (eg, syphilis, thyroid disease).

Surgical therapy for Ménière disease is reserved for medical treatment failures.

All patients should have rapid follow up with their primary care provider. Some patients may require referral to an otolaryngologist or neurologist. Salt-restricted diet, steroids, and the use of diuretics are often first-line therapies.^[10]

• References

Principles of Medical Management

Medical treatment of Ménière’s disease is aimed at symptomatic relief. In an acutely vertiginous patient, management is directed toward vertigo control.^[29] Intravenous (IV) or intramuscular (IM) diazepam provides excellent vestibular suppression and antinausea effects. Steroids can be given for anti-inflammatory effects in the inner ear. IV fluid support can help prevent dehydration and replaces electrolytes.

Typically, vestibulosuppressants and antinausea medications (eg, meclizine, prochlorperazine) are prescribed for prn use. Note that frequent and long-term use of these medications is not recommended. Long-term use of vestibulosuppressants can lead to bad vestibular compensation skills and result in poor balance function. Sedative effects can affect patient productivity. Furthermore, long-term tachyphylaxis may result.

During the quiescent phase, medical treatment of Ménière disease is tailored to each patient. Lifestyle and dietary changes are usually the first step. Avoiding trigger substances (eg, salt, chocolate, caffeine) alone may be sufficient. Smoking cessation also is recommended. If medications are required, a 3-month trial of a diuretic (eg, hydrochlorothiazide/triamterene) and dietary management are prescribed.

• References

Pharmacologic Therapy

Vestibulosuppressants

In general, medications that decrease symptoms (eg, meclizine [Antivert], droperidol [Inapsine], prochlorperazine [Compazine], diazepam [Valium], lorazepam [Ativan], alprazolam [Xanax]) only mask the vertigo. These masking agents are vestibulosuppressants and work by dulling the brain’s response to signals from the inner ear.

Diuretics and diureticlike medications

Some diuretics or medications with diuretic-like properties (eg, hydrochlorothiazide and triamterene [Dyazide], hydrochlorothiazide [Aquazide], acetazolamide [Diamox], methazolamide [Neptazane]) decrease fluid pressure in the inner ear. These medications help prevent attacks but do not help after the attack is triggered.

Although diuretics are often used, their efficacy has not been established with appropriate clinical trials. Loop diuretics should be used with caution due to the potential for ototoxicity.

Steroids

Steroids have also been helpful in treating endolymphatic hydrops because of their anti-inflammatory properties. Steroids can reverse vertigo, tinnitus, and hearing loss, probably by reducing endolymphatic pressure. Steroids can be given orally, intramuscularly, or even transtympanically. A trial of IM steroid injection followed by a tapering dose of oral steroids has been recommended.^[23] No trials evaluating the efficacy of systemic steroids for the treatment of Ménière disease have been done.^[30]

Although the transtympanic route is controversial, it is gaining wider acceptance throughout the otologic community. Transtympanic steroid injection has been shown to be beneficial in controlling loss of hearing and the number of vertigo attacks.^[31]

Aminoglycosides

Aminoglycosides are reserved for end-stage intractable Ménière disease. They are a class of antibiotics that were serendipitously discovered to be preferentially toxic to the vestibular (balance) end organ. Destruction of the vestibular end organ renders the brain insensitive to fluctuations in inner ear pressure brought on by Ménière disease.

When given systemically, aminoglycosides affect both ears. Although aminoglycosides can be used to treat extremely severe bilateral Ménière disease, such treatment leaves the patient with little or no balance function. The resulting complete loss of inner ear function (ie, Dandy syndrome) can be debilitating.

Currently, the preferred method of giving aminoglycosides is through transtympanic injections. This concentrates the medication in the affected ear, with little systemic or contralateral adverse effects. It has been very effective, as has been shown in many studies.

Histamine agonists

Histamine agonists such as betahistine (Serc) are widely used in Europe and South America for the treatment of Ménière disease. Betahistine’s mechanism of action has not been established with certainty, but it is thought to act by increasing circulatory flow to the cochlear stria vascularis^[32] or through inhibition of vestibular nuclei activity.^[33]

Many have reported success with the use of betahistine to mitigate symptoms of Ménière disease. Unfortunately, because this agent has not been approved by the US Food and Drug Administration (FDA), it is not discussed much in the United States.

• References

Meniett Device

One innovation in the treatment of Ménière disease is the Meniett device.^{[34, 35, 36, 37]} Its use is not precisely a medical treatment, and the device itself does not require surgical installation. It does, however, require insertion of a tympanostomy tube so that the device can work; therefore, its use may qualify as a surgical treatment.

The Meniett device delivers pulses of pressure to the inner ear via the tympanostomy tube. Although no one knows exactly why this approach works, some patients have symptomatic relief when the device is used on a daily basis. Because it is relatively new, long-term results have not been fully evaluated.

• References

Principles of Surgical Management

Surgical therapy for Ménière disease is reserved for medical treatment failures and is otherwise controversial.^[38] Historically, several surgical procedures have been invented, tested, and discarded. Surgical procedures are divided into 2 major classifications: destructive and nondestructive surgical procedures.

Endolymphatic hydrops causes fluid pressure accumulation within the inner ear, which causes temporary malfunction and misfiring of the vestibular nerve. These abnormal signals cause vertigo. Destruction of the inner ear, the vestibular nerve, or both prevents these abnormal signals from reaching the brain. As long as the opposite inner ear and vestibular apparatus function normally, the brain eventually will compensate for the loss of 1 labyrinth over the following weeks to months.

Destruction of one inner ear depends on the adequate function of the opposite ear. Unfortunately, Ménière disease can be bilateral (7-50%), in which case this method is contraindicated. Since balance and hearing are closely intertwined within the labyrinth, destruction of the balance portion carries a high risk of hearing loss. Note that destructive procedures are irreversible and reserved for severe cases.

Nondestructive surgical procedures are directed toward improving the state of the inner ear. They are less invasive than destructive procedures and do not preclude the use of other treatment modalities. Discussion here is limited to the 4 most generally accepted management options, as follows:

• Endolymphatic sac decompression or shunt placement^[39]
• Vestibular nerve section
• Labyrinthectomy
• Intratympanic injection of medications such as gentamicin^{[40, 41, 42]} or steroids^[43]

Go to Surgical Treatment of Meniere Disease for complete information on this topic.

• References

Endolymphatic Sac Decompression or Shunt

In theory, the endolymphatic sac procedure decreases endolymph pressure accumulation by removing some of the mastoid bone, which encases the endolymph reservoir. This procedure allows the reservoir sac to expand more freely, thus dissipating pressure. A drain or valve from the endolymphatic space to either the mastoid or subarachnoid space can be inserted as another means of further reducing pressure.

Success rates (in terms of controlling vertigo and stabilizing hearing acuity) with this procedure are reported at 60-80%. These success rates do not seem to differ significantly from those of endolymphatic sac decompression alone versus those that are coupled with shunt procedures. Morbidity and mortality rates of endolymphatic sac decompression are relatively low. The risk of hearing loss and facial nerve damage is minimal in experienced hands. Severe postoperative pain is unusual; in most cases the recovery period is typically short and uneventful.

The endolymphatic sac procedure is one of the most controversial issues in neuro-otology.^{[44, 45, 46]} Citing the famous Danish study, critics argue that endolymphatic surgery is no more effective than sham surgery and that any benefit is due to placebo effect. A Cochrane review article concluded that there is insufficient evidence to support endolymphatic sac surgery for the treatment of Ménière disease.^[47]

Proponents argue that patients indeed improve and, compared to destructive procedures, the endolymphatic sac procedures have low risk and morbidity rate. These procedures may provide relief in patients who have not responded to medical therapy.

Exposing the endolymphatic sac is essentially an extended mastoidectomy. Special care is taken to skeletonize the sigmoid sinus, posterior fossa dura, and posterior semicircular canal. The thin, egg-shelled bone is removed from the posterior fossa dura and sigmoid sinus.

The endolymphatic sac is distinguished from dura by color and texture differences. The sac is thicker and whiter than the surrounding tissue. The location of the sac can vary, but it is generally immediately posterior or posterior inferior to the posterior semicircular canal.

In endolymphatic sac decompression, the procedure is terminated after all of the bone overlying the sac is removed. The shunt procedures involve incising the lateral leaf of the sac and inserting a drainage tube into the internal lumen of the endolymphatic duct. As already mentioned, the shunt can drain into either the subarachnoid space or the mastoid space.

According to a recent study, endolymphatic sac surgery (sac decompression or mastoid shunt) was found to be effective at controlling vertigo in the short term (>1 yr of follow-up) and long term (>24 mo) in at least 75% of patients with Ménière disease in whom medical therapy had failed. Sac decompression and mastoid shunting techniques provided similar vertigo control rates. In addition, mastoid shunting, with and without silastic, also provided similar vertigo control rates. Nonuse of silastic, however, seemed to maintain stable or improved hearing in more patients, as compared to silastic sheet placement. The data suggested that once the sac is opened, placing silastic does not add benefit and may be deleterious.

Go to Surgical Treatment of Meniere Disease for complete information on this topic.

• References

Vestibular Nerve Section

For patients with useful hearing in the affected ear, sectioning the diseased vestibular nerve can be the ultimate solution. Although the hearing and balance functions are housed in a single common chamber within the inner ear, their neural connections to the brain separate into distinct nerve bundles as they course through the internal auditory canal. This anatomic separation allows balance function to be isolated and ablated without affecting hearing function.

Because this surgical procedure opens the internal auditory canal, it is similar to the approaches for an acoustic neuroma. Vestibular nerve sections typically are done through either a retrosigmoid or a middle fossa approach. The translabyrinthine approach does not spare hearing. It is used only for added insurance when labyrinthectomy is intended.

Most agree that the retrosigmoid approach (accomplished through a small craniotomy, posterior to the sigmoid sinus) is technically less difficult than the middle fossa approach. Exposure of the cerebellopontine angle allows visualization of the eighth cranial nerve.

Correct identification of the vestibular nerve is mandatory to avoid severing the facial nerve and cochlear nerve. Proper anatomic relationships must be confirmed. Because the nerve bundle rotates as it exits the internal auditory canal, the vestibular nerve moves from its lateral position to a more superior location. The vestibular nerves are closest to the tentorium. Facial nerve and cochlear nerve monitoring via intraoperative audiometric brainstem responses is essential.

The middle fossa approach for vestibular nerve section is more technically complex. The procedure creates a 5 X 5-cm middle fossa craniotomy just superior to the temporal line above the external ear canal. The middle fossa dura is retracted superiorly to expose the bone.

After proper anatomic landmarks are identified, the search for the internal auditory canal begins. Once the internal auditory canal is found and opened, the vestibular nerve is sectioned as laterally as possible. Fat is packed into the internal auditory canal and held in position by the temporal lobe dura. Finally, the craniotomy is closed.

The advantage of the middle fossa approach is that it achieves a slightly more complete ablation of vestibular function than the retrosigmoid approach. Because the vestibular fibers are cut immediately as they exit the vestibular end organ, the chance of stray vestibular fibers crossing over to travel along the facial and cochlear nerves is minimal. The retrosigmoid approach sections the vestibular nerve more medially, potentially after stray vestibular fibers have already crossed. Although unusual, failure of the retrosigmoid approach may be due to these crossed fibers.

The disadvantages of the middle fossa approach include the difficulty in finding the internal canal and the limited exposure within the canal because of the facial nerve’s position. Cutting the vestibular nerve without exerting pressure on the cochlear and facial nerves is difficult, in that the vestibular bundle lies deep within the canal. The risk of damaging the cochlear artery, with resulting hearing loss, is significant.

Vestibular nerve section has the advantage of a high rate of vertigo control (95-98%) with a high rate of hearing preservation in the operated ear (95%). The risks of this procedure, although rare, are similar to those of craniotomy and acoustic neuroma surgery and include the following: facial nerve damage, hearing loss, exacerbation of tinnitus and dizziness, cerebrospinal fluid leakage, headaches, hemorrhage, and infection (eg, meningitis).

Postoperatively, patients generally require 3-5 days of inpatient care. Accommodation to the surgical loss of 1 vestibular apparatus usually takes weeks to months. Vestibular rehabilitation during this period is often helpful.

Go to Surgical Treatment of Meniere Disease for complete information on this topic.

• References

Labyrinthectomy

Labyrinthectomy for Ménière disease has the advantage of a high cure rate (>95%) and is useful in patients whose hearing on the diseased side has been destroyed already by Ménière disease. Labyrinthectomy involves ablation of the diseased inner ear organs. It is a less complex procedure than vestibular nerve section, in that does not require entry into the cranial cavity. In addition, it is less invasive than vestibular nerve section.

In one study, endolymphatic sac surgery (sac decompression or mastoid shunt) was shown to be effective at controlling vertigo in the short term (>1 yr of follow-up) and long term (>24 mo) in at least 75% of patients with Ménière disease in whom medical therapy had failed. Sac decompression and mastoid shunting techniques provided similar vertigo control rates. Mastoid shunting, with and without silastic, also provided similar vertigo control rates. Nonuse of silastic, however, seemed to maintain stable or improved hearing in more patients, as compared to silastic sheet placement. The data suggested that once the sac was opened, placing silastic did not add benefit and may have been deleterious.^[48]

Labyrinthectomy carries less danger of cerebrospinal fluid (CSF) leak and meningitis because craniotomy is not required. Like those who undergo vestibular nerve section, labyrinthectomy patients require a few days of inpatient care. Accommodation to the surgical loss of 1 vestibular apparatus usually takes weeks or months. Vestibular rehabilitation during this period is also helpful.

The transcanal approach proceeds through the external ear canal. A tympanomeatal flap is first elevated. Next, a right-angle pick is inserted through the oval window and maneuvered to disrupt and scramble the nerve tissues of the labyrinth. A drill can be used to connect the round window and oval window to obtain better exposure to the neuroepithelium.

The basic mastoidectomy approach involves extending the mastoidectomy by drilling through the semicircular canals; this allows a more complete ablation of the labyrinthine neuroepithelium than can be achieved via the transcanal approach.

View Image

Intraoperative view of the left ear treated with labyrinthectomy; endolymphatic sac can be seen in this view.

• References

Cochlear Implant

Ten patients with Ménière disease who underwent a cochlear implant achieved substantial receptive communication improvement, according to the authors of the study. In addition, they noted that implantation seems to neither adversely alter the natural history of vestibular function nor notably exacerbate auditory symptoms.^[49]

In 10 patients with severe hearing loss (single-sided deafness) and recalcitrant vertigo attacks because of Ménière disease, simultaneous labyrinthectomy and cochlear implantation effectively relieved vertigo attacks and improved auditory function. According to the authors of this study, the cochlear implant restored auditory function to the deafened ear, and the binaural input appears to improve sound localization for most patients.^[50]

Go to Surgical Treatment of Meniere Disease for complete information on this topic.

• References

Transtympanic Perfusion of Medication

Transtympanic perfusion of medication was popularized by Dr. John Shea in 1995.^[51] The procedure is still evolving and, although variations have been devised, the concept remains the same.

In transtympanic perfusion, medications for Ménière disease are applied through a myringotomy within the middle ear cavity, where they presumably are absorbed through the round window membrane into the inner ear (see the image below). This is a relatively low-risk, simple procedure that applies a high concentration of medicine with minimal systemic effects. It is similar to the placement of tympanostomy tubes, which can be done in the office or in an outpatient setting.

If steroids are administered with this transtympanic technique, the procedure is classified as nondestructive. Transtympanic steroid application is useful, particularly when patients have poor tolerance for the systemic adverse effects of steroids. A higher inner ear concentration can be obtained with transtympanic steroids over oral or intramuscular steroids. Success rates seem favorable, although long-term studies are being gathered.

If aminoglycosides are administered, the surgery is classified as destructive. When given transtympanically, aminoglycosides can concentrate their effects in the affected ear.

Because streptomycin is difficult to obtain in the United States, owing to US Food and Drug Administration (FDA) restrictions, gentamicin^[52] is used more widely. Early studies show about 90% efficacy. Some authors report significant worsening of hearing in 5-15% of patients.

• References

Vestibular Rehabilitation

Vestibular therapy is a physical therapy and occupational therapy modality that helps habituate patients to their vestibular loss. It helps recalibrate a patient's balance by helping them compensate for the effects of the inner ear disorder. It is performed by repetitive balance exercises.

Because of the fluctuating nature of Ménière disease, vestibular therapy is not particularly useful as a primary treatment. However, it is useful in the rehabilitation of patients who have undergone vestibular ablation. In fact, vestibular rehabilitation is strongly recommended in those who have undergone aminoglycoside perfusion, labyrinthectomy, or vestibular nerve section. It can be helpful in teaching patients to cope with vertigo and imbalance.

• References

Diet and Activity

Dietary measures

Dietary management is appropriate in patients not severely affected; patients avoid substances that may trigger or exacerbate fluid pressure buildup in the inner ear. For Ménière disease, much as for systemic hypertension, the goal is to reduce the total body fluid volume. This, in turn, may reduce the inner ear fluid volume.

Because sodium seems to play a major role in fluid retention within the inner ear, avoiding foods with high sodium content (eg, pizza, preserved foods, smoked fish) is paramount. Note that many preserved and smoked foods contain sodium nitrite, which can contribute to high sodium content. Consult with a nutritionist to establish a rigid salt-restricted diet (1.5 g sodium/d).

Activity restriction

Endolymphatic hydrops does not preclude regular activity. Exercise is recommended in moderation. However, because of the unpredictable nature of the disease, balance-intensive, dangerous tasks (eg, especially climbing ladders) should be avoided.

• References

Prevention

Quality evidence is lacking regarding deterrence and prevention of acute attacks of Ménière disease; however, a salt restricted diet, as described elsewhere (see Diet and Activity), is often suggested. In addition, avoidance of trigger substances may help prevent acute episodes. The following substances should be avoided:

• Caffeine
• Nicotine
• Chocolate, which has shown to be a potent trigger substance
• Tobacco
• Alcohol, particularly red wine and beer
• Foods with high cholesterol or triglyceride content
• Foods with high carbohydrate content
• Excessive sweets and candy

Finally, it is often suggested that patients try to avoid loud noises and to make use of stress-reduction techniques.

• References

Consultations

Because the differential diagnosis is vast, many specialists are often consulted, including the following:

• Otolaryngologist
• Neurologist
• Cardiologist
• Endocrinologist
• Internist
• Physical medicine/rehabilitation specialist (especially in the postoperative period)

This can be a drain on financial resources. “Shotgun” multispecialty consultations are not recommended.

Typically, the specialist most suited to care for Ménière disease patients is a neurotologist (otolaryngologist or neurologist who is interested in dizziness). Strategic consultation with these physicians first provides cost-effective triage.

• References

Medication Summary

The goals of pharmacotherapy are to reduce morbidity and prevent complications. Medication is for both symptomatic and prophylactic use.

Medical treatment of Ménière’s disease is aimed at symptomatic relief. The primary target is relief of vertiginous symptoms. Antiemetics may be used for nausea and vomiting. A trial of intramuscular steroid injection followed by a tapering dose of oral steroids has been recommended. Transtympanic steroid injection has been shown to be beneficial in controlling loss of hearing and the number of vertigo attacks.

Diuretics are often used, but their efficacy has not been established with appropriate clinical trials. Loop diuretics should be used with caution due to the potential for ototoxicity. Vasodilators, such as betahistine, have been used for the treatment of vertigo but are not FDA approved for this indication.

• References

Meclizine (Antivert, Bonine, Medi-Meclizine)

• Dosing, Interactions, etc.

Clinical Context:  Meclizine decreases the excitability of the middle ear labyrinth and blocks conduction in middle ear vestibular-cerebellar pathways. These effects are associated with relief of nausea and vomiting.

• References

Dimenhydrinate (Dramamine, Driminate, TripTone)

• Dosing, Interactions, etc.

Clinical Context:  Dimenhydrinate is used for prophylaxis of vestibular disorders that may cause nausea and vomiting. Through its central anticholinergic activity, it diminishes vestibular stimulation and depresses labyrinthine function. It is a 1:1 salt of 8 chlorotheophylline and diphenhydramine.

• References

Scopolamine (Isopto, Scopace, Transderm Scop)

• Dosing, Interactions, etc.

Clinical Context:  Scoploamine blocks the action of acetylcholine at parasympathetic sites and antagonizes the actions of histamine and serotonin. Transdermal scopolamine may be the most effective agent for motion sickness. Its use in treatment of vestibular neuronitis is limited by its slow onset of action.

• References

Promethazine (Phenergan, Phenadoz, Promethegan)

• Dosing, Interactions, etc.

Clinical Context:  Promethazine is an antidopaminergic agent that is effective in the treatment of emesis. It blocks postsynaptic mesolimbic dopaminergic receptors in the brain and reduces stimuli to the brainstem reticular system.

• References

Prochlorperazine (Compro)

• Dosing, Interactions, etc.

Clinical Context:  Prochlorperazine is an antidopaminergic drug that blocks postsynaptic mesolimbic dopamine receptors, has an anticholinergic effect, and can depress the reticular activating system; it may be responsible for relieving nausea and vomiting.

• References

Metoclopramide (Reglan, Metozolv)

• Dosing, Interactions, etc.

Clinical Context:  Metoclopramide is a dopamine antagonist that stimulates acetylcholine release in the myenteric plexus. It acts centrally on chemoreceptor triggers in the floor of the fourth ventricle, and this action provides important antiemetic activity.

• References

Droperidol

• Dosing, Interactions, etc.

Clinical Context:  Droperidol may reduce emesis by blocking dopamine stimulation of the chemoreceptor trigger zone.

• References

Diazepam (Valium, Diastat)

• Dosing, Interactions, etc.

Clinical Context:  Diazepam depresses all levels of the central nervous system (CNS), possibly by increasing the activity of GABA. To avoid adverse effects, individualize the dosage and increase it cautiously.

• References

Alprazolam (Xanax, Niravam)

• Dosing, Interactions, etc.

Clinical Context:  Alprazolam binds receptors at several sites within the central nervous system, including the limbic system and reticular formation. Effects may be mediated through GABA receptor system.

• References

Class Summary

Antiemetics act as vestibulosuppressants to decrease symptoms but generally only mask the vertigo. They dull the brain’s response to the inner ear’s signals. Benzodiazepines act as antiemetics and vestibulosuppressants by binding to specific receptor sites, which apparently potentiates the effects of gamma-aminobutyric acid (GABA) and facilitates inhibitory GABA neurotransmission and other inhibitory transmitters. These effects may offer benefits in the treatment of vertigo and emesis. Examples of vestibulosuppressants include meclizine, dimenhydrinate, droperidol, prochlorperazine, diazepam, lorazepam, alprazolam, and scopolamine.

• References

Prednisone

• Dosing, Interactions, etc.

Clinical Context:  Prednisone may decrease inflammation by reversing increased capillary permeability and suppressing polymorphonuclear (PMN) activity.

• References

Class Summary

The anti-inflammatory properties of steroids are helpful in treatment of endolymphatic hydrops, probably by reducing endolymphatic pressure; steroids actually can reverse the vertigo, tinnitus, and hearing loss. No trials evaluating the efficacy of systemic steroids for the treatment of Ménière’s disease have been done.^[30]

• References

Hydrochlorothiazide (Microzide)

• Dosing, Interactions, etc.

Clinical Context:  Hydrochlorothiazide inhibits reabsorption of sodium in distal tubules, causing increased excretion of sodium and water as well as potassium and hydrogen ions.

• References

Triamterene (Dyrenium)

• Dosing, Interactions, etc.

Clinical Context:  Triamterene is a potassium-sparing diuretic with relatively weak natriuretic properties. It exerts a diuretic effect on the distal renal tubule to inhibit reabsorption of sodium in exchange for potassium and hydrogen. It increases sodium excretion and reduces excessive loss of potassium and hydrogen associated with hydrochlorothiazide. It is not a competitive antagonist of mineralocorticoids, and its potassium-conserving effect is observed in patients with Addison disease (ie, without aldosterone). Triamterene's onset and duration of activity is similar to hydrochlorothiazide.

• References

Acetazolamide (Diamox)

• Dosing, Interactions, etc.

Clinical Context:  Acetazolamide is a carbonic anhydrase inhibitor that acts by inhibiting the conversion of carbon dioxide to bicarbonate, thus it may decrease vertiginous symptoms.

• References

Methazolamide (Neptazane)

• Dosing, Interactions, etc.

Clinical Context:  Methazolamide reduces aqueous humor formation by inhibiting the carbonic anhydrase enzyme, which results in decreased vertiginous symptoms.

• References

Class Summary

Diuretics or diuretic-like medications actually can decrease fluid pressure load in the inner ear. These medications help prevent attacks but are ineffective once an attack is triggered. Examples include hydrochlorothiazide, hydrochlorothiazide/triamterene, acetazolamide, and methazolamide.

• References

Ephedrine

• Dosing, Interactions, etc.

Clinical Context:  Ephedrine stimulates the release of epinephrine stores, producing alpha- and beta-adrenergic

• References

Class Summary

Adrenergic agonists are useful in treating vertigo, but their mechanism of action is unclear.

• References