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Meniere’s diseaseHamed Sajjadi, Michael M Paparella

Meniere’s disease is a chronic illness that aff ects a substantial number of patients every year worldwide. The disease is characterised by intermittent episodes of vertigo lasting from minutes to hours, with fl uctuating sensorineural hearing loss, tinnitus, and aural pressure. Although there is currently no cure, more than 85% of patients with Meniere’s disease are helped by either changes in lifestyle and medical treatment, or minimally invasive surgical procedures such as intratympanic steroid therapy, intratympanic gentamicin therapy, and endolymphatic sac surgery. Vestibular neurectomy has a very high rate of vertigo control and is available for patients with good hearing who have failed all other treatments. Labyrinthectomy is undertaken as a last resort and is best reserved for patients with unilateral disease and deafness.

IntroductionProsper Ménière fi rst described this disease in 1861.1 His main contribution to its diagnosis was a description of the disease entity with episodic vertigo and ringing in the ears; he challenged general terminology at the time that named this disease apoplectic cerebral congestion, implying a disorder of the brain. Ménière described these episodes of vertigo and fl uctuating hearing loss as being associated with the peripheral end organ of the inner ear rather than with the brain. He and other investigators2,3 called it “glaucoma of the inner ear”.

In 1927, Guild4 identifi ed the endolymphatic sac as the site of “outfl ow of endolymph” in his study of guineapigs. This study was a major insight into the mechanics of endolymphatic fl ow in the inner ear. Later that same year, Portmann3 described his fi rst endolymphatic sac surgery for the Meniere’s disease complex. Endolymphatic sac surgery has remained the main non-destructive form of surgical treatment for Meniere’s disease since the early 1900s. 1 year after Portmann’s description of sac surgery, Dandy5 proceeded with vestibular neurectomy, trying to isolate the vestibular system from the brain and thus cure patients of vertigo.

In 1943, Altmann and Fowler6 concluded that problems in production and absorption of endolymph can lead to Meniere’s disease. In a landmark study in 1967, Kimura7 investigated the fi rst animal model with guineapigs and showed that blockage of the endolymphatic sac and duct causes obstruction of endolymphatic outfl ow, leading to hydrops of the inner ear.

EpidemiologyMeniere’s disease remains a diffi cult disease to diagnose, especially in the early stages when not all its symptoms might be present. Consequently, the incidence and prevalence of the disease in any population is diffi cult to ascertain.8 Frequently, patients with Meniere’s disease present to the emergency department with sudden onset of vertigo and are inaccurately diagnosed as having labyrinthitis and discharged home.8 In early stages, Meniere’s disease might present with only cochlear symptoms such as hearing loss and pressure or fullness in the ear without true vertigo or even ringing in the ears. In 1995, the American Academy of Otolaryngology—

Head and Neck Surgery (AAO-HNS) established a specifi c set of criteria for the diagnosis of Meniere’s disease (panel).9

Few articles have been published on the epidemiology of Meniere’s disease. In 1973, Stahle and colleagues reported a prevalence of 46 cases per 100 000 population.10 From 1975 to 1990, several studies from Japan, which were undertaken for a Research Committee on Meniere’s Disease and a Committee on Peripheral Vestibular Disorders, indicated a fairly constant prevalence of 17 cases per 100 000 population.11,12 Kotimaki and colleagues13 analysed the Finnish population of 5 million people between 1992 and 1996 with the AAO-HNS recommendations. They reported a prevalence of 43 per 100 000 and an average yearly incidence of 4·3 per 100 000 population.13

Most studies suggest a slight female preponderance of up to 1·3-times that of men.9 The disease seems to be much more common in adults in their fourth and fi fth decade than in younger people, although it has been noted in children;14 Meyerhoff and colleagues15 noted a 3% prevalence of paediatric Meniere’s disease. A strong positive family history exists in patients with Meniere’s disease; several studies have indicated that up to 20% of family members have similar symptoms.14,16–18 Meniere’s disease also seems to aff ect more white people of northern European descent than it does the African and black races.19,20

Lancet 2008; 372: 406–14

Department of Otolaryngology Head and Neck Surgery,

Stanford University Medical Center, San Jose, CA, USA

(H Sajjadi MD); and Department of Otolaryngology Head Neck

Surgery, University of Minnesota, Minneapolis, MN,

USA (Prof M M Paparella MD)

Correspondence to:Dr Hamed Sajjadi, Department of

Otolaryngology Head and Neck Surgery, Stanford University

Medical Center, 2577 Samaritan Drive Ste 845, San Jose,

CA 95124, USAotology@hotmail.com

Search strategy and selection criteria

We searched Medline, ENT Rez, Pubmed, and the Cochrane Library for publications in the past 10 years, with the terms “Meniere’s disease” and “Endolymphatic sac”, “Gentamicin middle ear perfusion”, and “Steroid middle ear perfusion”. We largely used materials published within the past 5 years but did not exclude older publications that were commonly referenced and highly regarded. We also searched the reference lists of articles identifi ed by this search strategy and selected those that we judged relevant. Several review articles or book chapters were included because they provide comprehensive overviews that are beyond the scope of this Seminar. Only references published in English were included.

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A study reviewing fi ve generations of the same family from Sweden showed a very strong familial trend for Meniere’s disease.10 Nine of 25 family members showed some problems of the inner ear, six of whom satisfi ed the AAO-HNS criteria for diagnosis of Meniere’s disease. Morrison21 studied 41 families in which at least one member had the disorder. Those fi ndings suggested a 60% penetrance in an autosomal dominant pattern in families with the disease, with strong anticipation, meaning that an earlier age of onset and more severe symptoms are detected in each successive generation with the disease.

Histocompatibility antigens (HLA) have been intensively studied by several investigators.22 Arweiler and colleagues23 investigated 48 patients and detected a 90% prevalence of HLA-A2 in patients with a family history, and a 75% prevalence in those without a family history. These investigators propose a multifactorial aetiology for Meniere’s disease, combined with a genetic predisposition caused by mutations of the short arm of chromosome 6. Furthermore, Paparella16 detected a 20% incidence of positive family history in patients with Meniere’s disease in a review of 500 patients.

PathophysiologyMeniere’s disease is characterised by intermittent episodes of vertigo lasting from minutes to hours, with fl uctuating sensorineural hearing loss, tinnitus, and aural pressure.24 It has been classifi ed into typical Meniere’s disease, with all the cochlear and vestibular

symptoms, and atypical Meniere’s disease, with either cochlear symptoms (eg, hearing loss, tinnitus, aural pressure) or vestibular symptoms (eg, vertigo alone with aural pressure but no hearing loss or tinnitus).25 The primary histopathological correlate is endolymphatic hydrops. Paparella used the notion of “lake-river-pond” to explain the occurrence of malabsorption of endolymph leading to hydrops.26 This notion describes the endolymphatic sac as a pond, with the vestibular aqueduct (the river) connecting it to the endolymphatic fl uid space that is like a lake. When there is an obstruction near the endolymphatic sac or duct, a backlog of endolymphatic fl uid is created, leading to hydrops.

Histological studies have suggested that endolymph is primarily produced in the stria vascularis, and some production also occurs in the planum semilunatum and dark vestibular cells.27 Endolymph is then absorbed in the endolymphatic duct and sac through an active transport mechanism. Longitudinal fl ow proceeds slowly, and radial fl ow rapidly, into the endolymphatic sac.27 Gibson and Arenberg28 suggested that because of obstruction of the endolymphatic sac, hormones such as saccin might be produced to increase production of endolymph to overcome the obstruction. Furthermore, the sac might also produce glycoproteins that osmotically attract endolymph towards it. As a result of overfl ow of endolymph behind the obstruction, the obstruction might be relieved and the sudden outfl ow across the sac could lead to vertigo. Kimura and colleagues29 devised an animal study showing that obliteration of the ductus reuniens causes cochlear hydrops.

Many histological features have been seen in patients with Meniere’s disease by use of temporal-bone studies. These studies include fi ndings of perisaccular fi brosis,30 atrophy of the sac and loss of epithelial integrity,27 hypoplasia of the vestibular aqueduct,31 and narrowing of the lumen of the endolymphatic duct.32 We have shown that the sigmoid sinus is signifi cantly anteriorly and medially displaced in patients with Meniere’s disease compared with healthy controls.33 Our study suggested that the forwardly located lateral sinus can cause vascular compression of the endolymphatic sac leading to obstruction and hydrops, which would be a genetic predisposition of an anatomical abnormality. Revisional surgery on the endolymphatic sac has shown that surgical removal of perisaccular fi brosis can allow patients who had initially good results with an endolymphatic sac enhancement (ESE) to improve and reduce their symptoms.34,35

Revision of ESE surgery has contributed signifi cantly to our knowledge of the pathophysiology of this disease. Revisional ESE is undertaken for patients who have benefi ted from the primary endolymphatic surgery for at least 1 year postoperatively, and then have recurrence of their symptoms. Several investigators have noted substantial pathological fi ndings during repeat surgery, once ESE has been done.34–36 These fi ndings have included

Panel: The American Academy of Otolaryngology—Head and Neck Surgery criteria for diagnosis of Meniere’s disease (1995)

1 Recurrent spontaneous and episodic vertigo. A defi nitive spell of vertigo lasting at least 20 min, often prostrating, accompanied by disequilibrium that can last several days; usually nausea or vomiting, or both; no loss of consciousness. Horizontal rotatory nystagmus is always present

2 Hearing loss (not necessarily fl uctuating)3 Either aural fullness or tinnitus, or both

Certain Meniere’s diseaseDefi nite disease with histopathological confi rmation

Defi nite Meniere’s diseaseTwo or more defi nitive episodes of vertigo with hearing loss, plus tinnitus, aural fullness, or both

Probable Meniere’s diseaseOnly one defi nitive episode of vertigo and the other symptoms and signs

Possible Meniere’s diseaseDefi nitive vertigo with no associated hearing loss or hearing loss with non-defi nitive disequilibrium

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a hypoplastic mastoid air-cell system with perisaccular fi brosis, discolouration of the silastic sheathing inserted in the primary procedure, and granulation tissue fi lling the mastoid and the perisaccular space, which all create compression leading to saccular obstruction. Complete decompression of the sigmoid sinus and the mastoid cavity is the most important surgical contribution to correction of the symptoms of Meniere’s disease.

DiagnosisThe clinical picture of Meniere’s disease includes fl uctuating sensorineural hearing loss accompanied by aural pressure, tinnitus, and episodic vertigo. The hallmark of the disease is its fl uctuation, waxing, and waning of symptoms. Typical Meniere’s disease includes all symptoms; the episodic vertigo lasts from several minutes to hours, with positional vertigo in between and during attacks. Furthermore, almost all patients note a sense of pressure or fullness in the ear and various forms of tinnitus. Most patients develop unilateral symptoms, and a large proportion might develop bilateral disease many years after the onset of the unilateral symptoms. Several studies have reported the rate of bilateral Meniere’s disease to be as high as 50% after many years of the initial diagnosis.37

The AAO-HNS subcommittee on Hearing and Equilibrium and Its Measurements has proposed various consensual statements to reach a defi nition of Meniere’s disease (panel).25 Meniere’s disease remains a clinical diagnosis; a detailed history and a complete physical examination are necessary for a diagnosis to be made. Once the history and physical examination have been completed, the essential tests needed to guide clinicians to make the diagnosis include a full audiometric assessment and possibly video nystagmography or electonystagmographic testing with bithermal caloric evaluation. Electrocochleography is an optional test to augment the diagnosis of Meniere’s disease. In all unilateral cases, MRI of the brain with views of the internal auditory canal with and without contrast is needed to rule out retrocochlear pathological disorders that can present with sensorineural hearing loss, tinnitus, and vertigo. CT-scanning of temporal bone is of little value in diagnosis of Meniere’s disease. Standard lateral mastoid radiographs could be obtained to aid diagnosis by documenting the forward location of the sigmoid sinus, which is seen in almost all patients with this disease.37

Most patients with Meniere’s disease present with an up-sloping low-frequency sensorineural hearing loss that, with time and after many fl uctuations, could lead to a fl at sensorineural hearing loss. In very few patients, a slight conductive component to the hearing loss might also be noted initially.36 This conductive loss is diffi cult to explain, but has led to incorrect diagnoses of Eustachian tubal dysfunction in patients with early presentation of Meniere’s disease. Serial audiograms are very helpful in

diagnosis, by documenting fl uctuation of sensorineural hearing loss. Paparella and several investigators38,39 have recorded a so-called peak pattern of audiographical fi ndings with sensorineural hearing loss of low frequencies, with better hearing at 2000 Hz and worse hearing at frequencies greater than 2000 Hz.

The most important fi nding in vestibular testing of patients for Meniere’s disease is the unilateral vestibular hypofunction seen on bithermal caloric testing.40 However, up to 50% of patients with Meniere’s disease might still have completely normal nystagmography and bithermal caloric assessments, even with incapacitating vertigo.41 In patients who are unable to undergo MRI because of installation of a pacemaker or other reasons, auditory brainstem response audiometry can provide a less accurate alternative to rule out retrocochlear pathological disorders.41

Patients who present with incapacitating vertigo, sensorineural hearing loss, and all the symptoms suggestive of Meniere’s disease should still undergo routine haematological tests to rule out more common causes of vertigo and ill feeling. These tests include a complete blood count to rule out anaemia, leukaemia, and other disorders, as well as a sedimentation rate to check for any occult infl ammatory processes. Tests of the thyroid functions; cholesterol, lipids, and triglycerides; a fasting blood glucose; and haemoglobin A1C are suggested to rule out diabetes and other lipid and cholesterol abnormalities. All patients should have a fl uorescent Treponema antibody-absorption test for syphilis. These tests are helpful to assess the general health of patients presenting with such incapacitating symptoms, and to avoid missing other medical problems that are correctable.42

Migraine-associated dizziness is a fairly new diagnosis that has several clinical similarities to Meniere’s disease, especially to the vestibular Meniere’s variant. 43 A detailed history of headaches with and without concomitant dizziness is very important for diff erentiation between these illnesses. Patients with migraines frequently have an aura with their headaches, as well as nausea, photophobia, phonophobia, and visual scintillating scotoma. Patients with migraine-associated dizziness usually have normal hearing or symmetrical, incidental, non-fl uctuating hearing loss.44 Aural pressure, which is a hallmark of patients with Meniere’s disease, is mostly absent in those with migraines. Previously, many patients with migraine-associated dizziness might have been inadvertently diagnosed as having Meniere’s disease, thus aff ecting results of treatment outcome. Migraine associated dizziness should be recognised and diff erentiated from Meniere’s disease early in the clinical work-up phase.

Medical and surgical managementSeveral medical and surgical remedies have been off ered to patients with Meniere’s disease over the past 150 years. The plethora of medical and surgical therapies

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signifi es that no one eff ective treatment is available for these patients. However, most will be helped by a combination of medical therapy, psychological counselling and reassurance, and lifestyle and dietary changes.

The cure for this disease is yet to be discovered; it could lie in genetic re-engineering that might need a functioning labyrinth for an eff ective outcome. Therefore, destructive procedures that might preclude implementation of a possible cure for patients in the future should be avoided. For us to continue to be conservative by preserving the structures of the inner ear both chemically and physically and working at alleviation of the patient’s symptoms without destroying these structures, as much as possible, would be prudent.

The medical and surgical options available to treat patients with Meniere’s disease should be off ered according to the severity of the patient’s symptoms and failure to respond to appropriate therapy. The following options are listed in order of disease severity, and the fi gure gives a treatment algorithm.

Lifestyle changesA strong association with seasonal allergies and circulating immune-complexes exists in patients with known diagnoses of Meniere’s disease.45,46 Simple allergy-avoidance and changes in lifestyle could alleviate some of the allergy symptoms associated with this disease and allow for improved quality of life for patients. Some studies have reported a signifi cant reduction (up to 62%) in both frequency and severity of attacks of vertigo in

patients with Meniere’s disease after starting immunotherapy for allergies.47

Patients with symptoms of Meniere’s disease react adversely to consumption of large quantities of caff eine, chocolate, alcohol, and salt. However, the actual mechanism and pathophysiology of this adverse reaction is unknown. Some patients might actually have an allergy to some of these items. Therefore, food allergies should be investigated in patients with Meniere’s disease and should be treated and avoided as much as possible.

All patients with Meniere’s disease are encouraged to reduce their salt intake to a maximum of 2 g per day, and to 1·5 g per day if tolerated. They are also asked to avoid all sources of caff einated products, to reduce their intake of chocolate, and to avoid all tobacco and alcoholic products as much as possible. As early as 1934, Furstenberg showed the relation between sodium retention and Meniere’s disease, and recommended a substantial reduction in intake of sodium.48 Several other investigators have also reported this relation and shown the effi cacy of diuretics for reduction of these symptoms.49,50

DiureticsRecent studies have suggested no relation between use of diuretics and Meniere’s disease; however, we believe that most of the time diuretics are a fairly safe option and are off ered to all patients.51 Once diuretics are used, a repeat blood test should be done a week later to ensure that the concentration of potassium in the blood has not decreased; even though potassium-sparing diuretics are frequently used, there is always a slight chance of loss of potassium because of diuretic use. The most commonly used diuretic is a combination of hydrochlorothiazide and triamterene. Patients who are allergic to sulpha could use acetazolamide or chlorthalidone.42,52

SteroidsSteroid therapy has been used in treatment of acute and chronic symptoms of Meniere’s disease—both oral steroids and intratympanic steroid injections have been tried. Trials of steroids could be of substantial value to most patients since a large number with Meniere’s disease have allergies and also because of problems with immune-mediated occurrences. For acute attacks, intramuscular or intravenous methylprednisolone can be used to control the severe hearing loss and vertigo followed by oral prednisone at a dose of 1 mg/kg, given on a daily basis for 10–14 days before a slow tapering dose can take eff ect for the next 2 weeks.

If patients do not respond to the oral steroids and their hearing continues to deteriorate, intratympanic methyl-prednisolone or dexamethasone injections can be given. Patients who have a pronounced response to oral or intratympanic steroids might have other immune-mediated inner-ear diseases and should have a complete work-up for autoimmune problems. Consultation with a

Diagnosis confirmed

Meniett device

Endolymphatic sac enhancement surgery

Vesticular neurectomy

Labyrinthectomy

Low salt diet,avoidance of caffeine,chocolate, alcohol,tobacco products

Diuretics Oral, intramuscular, orintratympanic steroids

All patients

3–6 month trial

Treatment failure

Treatment failure

Treatment failure

Treatment failure

Gentamicin perfusion

Treatment failure

Acute attacks

Figure: Treatment algorithm for Meniere’s disease

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rheumatologist who is interested in taking care of such patients can be very benefi cial.42 In a randomised and blinded controlled trial at a tertiary referral centre, Morales and colleagues53 randomly assigned patients to oral acetazolamide or oral acetazolamide and prednisone and assessed their responses. The investigators’ fi ndings suggested a signifi cant reduction in patients’ refractory vertigo and tinnitus with oral prednisone therapy, but they noted no change in patients’ aural fullness or hearing.53

Intratympanic dexamethasone injection has been used by several investigators to control symptoms of vertigo and hearing loss in patients with Meniere’s disease. In a 2-year prospective placebo-controlled double-blinded randomised trial, Garduno-Anaya and colleagues54

studied the eff ect of dexamethasone perfusion of the inner ear in patients with unilateral Meniere’s disease. They concluded that dexa methasone at 4 g/L injected into the ear trans tympanically under local anaesthesia showed an 82% com plete control of vertigo compared with 57% con trol in the placebo group. They noted a 48% subjective improvement in tinnitus, 35% improve-ment in hearing loss, and 48% improve ment in aural fullness compared with signifi cantly lower proportions in the control group.54

Since most patients with Meniere’s disease can present with sudden hearing loss, intratympanic steroids might also be of benefi t to those with sudden hearing loss in Meniere’s disease.55–59 In a study to assess the results of intratympanic steroid therapy with dexamethasone in patients with cochlear hydrops, Hillman and colleagues60 concluded that hearing improved in 40% of patients, was worse in only 4%, and did not change in 56% who received intratympanic steroids for hydrops.

Gentamicin transtympanic perfusionDestructive treatments can be used in patients with intractable vertigo. One such treatment, with intra-tympanic aminoglycosides, was fi rst used to treat unilateral intractable Meniere’s disease more than 30 years ago.61 The present drug of choice seems to be gentamicin, which causes direct damage to both the sensorineural epithelium and the dark cells of the labyrinth, thus aff ecting vesti bular function and cochlear function. Nedzelski and col-leagues62 presented his preliminary report on 33 patients given intratympanic gentamicin between 1988 and 1989 for intractable vertigo. Hearing improved in 36% of these patients, was unchanged in 39%, and worsened in 25%. He reported an 89·7% control of vertigo. Parnes and Ridell61 also showed a similar proportion of hearing loss in their preliminary series of patients.

Driscoll and colleagues63 proposed a low-dose single treatment with gentamicin for Meniere’s disease. He concluded that low-dose intratympanic gentamicin was a safe and simple procedure that was eff ective in the control of defi nitive episodes of vertigo in most patients with unilateral Meniere’s disease; control of vertigo was

obtained in 84% of patients with a low incidence of hearing loss. McFeely and colleagues64 studied 25 consecutive patients given intratympanic gentamicin for Meniere’s disease between 1992 and 1996 and reported a 20% prevalence of pronounced sensorineural hearing loss and 8% prevalence of total deafness after genta micin treatment. They also reported an 88% complete con trol of vertiginous spells with another 12% substantially controlled. Kaasinen and colleagues65 investigated 93 patients with intractable Meniere’s disease who were given serial injections of intra -tympanic gentamicin and followed up for 2 years. They reported a complete resolution of vertigo in 81% of patients, with an 11% prevalence of total sensorineural hearing loss. The investigators concluded that this method was a safe and eff ective way to treat vertiginous attacks in patients with Meniere’s disease.

Minor66 devised a protocol using transtympanic gentamicin injections for patients with vertigo in Meniere’s disease, titrating it to development of signs of unilateral vestibular hypofunction, as shown by total loss of caloric stimulation response on video nystagmagraphy or electrode nystagmagraphy tests. He reported a very low prevalence of sensorineural hearing loss in only one patient (3%) and a 91% control of vertigo.66 Initial studies had recommended a complete ablation of vestibular function with gentamicin to obtain successful results in patients with vertigo.67 However, results from studies now recommend that a partial ablation could be just as eff ective with less risk of sensorineural hearing loss.68 The main risk of intratympanic gentamicin treatment for vertigo is the sensorineural hearing loss and associated disequilibrium, which are common complaints after this treatment. Many studies suggest that a complete ablation of function is not necessary for control of vertigo, and that partial ablation could reduce the risk of hearing loss to just 20–21%.68

An important indicator for intratympanic gentamicin therapy seems to be the control of vertigo in non-serviceable ears—ie, speech reception threshold worse than 50 db and speech discrimination score of less than 50%—or in patients who have failed endolymphatic sac surgery.63 Transmastoid labyrinthectomy has traditionally been off ered for non-serviceable ears in patients with Meniere’s disease. This method has been the gold standard, and it is very eff ective in eradication of vertigo in more than 94% of patients. However, transtympanic gentamicin therapy can provide a minimally-invasive ambulatory means with low morbidity and few side-eff ects, which is very cost eff ective for management of vertigo in these patients with non-serviceable ears.69 Marzo and Leonetti70 have also shown the effi cacy of intratympanic gentamicin therapy for patients who have failed endolymphatic sac surgery, thus reducing the need for vestibular neurectomy in those with intractable disease.

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Colletti and colleagues71 reported auditory results after 209 patients had undergone vestibular nerve section and compared these fi ndings with 24 patients who had received intratympanic gentamicin injections. The auditory data indicated a slight drop in scores for speech discrimination in those who had vestibular nerve sections, from 85% to 82% postoperatively. However, in the group who received gentamicin, scores dropped from 87% to 65% after treatment. This signifi cant diff erence between the two groups suggested a much higher rate of sensorineural hearing loss in the gentamicin group than in those who had vestibular neurectomy. The control of vertigo in patients who had vestibular neurectomy was 95·8% compared with 75% in those who received gentamicin. Patients have to be counselled about the substantial risk of sensorineural hearing loss and disequilibrium that might result after gentamicin therapy. Furthermore, they should be informed that intratympanic gentamicin therapy is a chemical ablation of the vestibular system, and as such it remains a destructive procedure.

Pressure pulse treatmentA fairly new non-invasive method for treatment of intractable vertigo in patients with Meniere’s disease has been positive pressure provided through a pulse-generator into the ear canal.72,73 The device for this procedure is called a Meniett (Medtronic Inc, Jacksonville, FL, USA). Odkvist and colleagues74 compared the Meniett device with a placebo (a similar device without any pressure delivered). They noted a signifi cant reduction in the frequency and intensity of vertigo, tinnitus, and aural pressure in the group using the Meniett device compared with the placebo group.

Densert and Sass75 studied 37 patients with a diagnosis of defi nitive Meniere’s disease and active vestibular symptoms. They concluded that the pressure treatment provided by the Meniett device was eff ective in control of vertigo in a large number of patients with intractable Meniere’s disease. No signifi cant side-eff ects were associated with use of the Meniett. However, Boudewyns and colleagues76 have shown that the long-term effi cacy of the Meniett device is poor.

Endolymphatic sac surgeryEndolymphatic sac surgery for Meniere’s disease was fi rst proposed by Portmann3 80 years ago; it has stood the test of time and continues to be off ered to patients with Meniere’s disease, who receive substantial improvement in hearing and attacks of vertigo. The endolymphatic subarachnoid shunt procedure was made common practice by William House77 in 1962, and the endolymphatic mastoid sac-enhancement surgery by Paparella and co-workers78 in 1980. The endolymphatic sac to mastoid enhancement operation has proven safe and eff ective in alleviation of intractable vertigo in more than 76% of patients.79,80 Paparella and Fina81 reported

75% total elimination of vertigo and 90% improvement of vertigo after sac enhancement surgery.

The main technical feature of endolymphatic sac surgery has been a wide decompression of the sigmoid sinus, localisation of the endolymphatic sac, and insertion of a custom-made Silastic sheeting along with Silastic spacers in the sac and perisaccular area. The risk of sensorineural hearing loss after endolymphatic sac decompression is less than 2%. Paparella and Fina81 investigated more than 2000 ESE surgeries that were undertaken over 35 years and noted an incidence of revision of only 5%, usually 3–4 years later. Preservation of hearing was maintained in more than 98% of patients, and up to 40% of patients had better hearing outcomes after ESE than they did before the procedure. Only 2% of patients sustained serious sensorineural hearing loss after ESE.

However, Thomsen and colleagues82 concluded that ESE surgery had no advantages compared with a placebo operation.82 Although the research has been cited by sceptics of ESE surgery extensively, the investigators’ conclusion was that both the ESE surgery group and the placebo group had 70% success in controlling vertigo attacks. Their follow-up study in 1986 stated the same conclusion.83 In our opinion this study was fl awed in several areas. First, it was a very small study of only 30 patients. Second, patients in the placebo group had a complete mastoidectomy under general anaesthesia. Many factors during general anaesthesia can aff ect body haemodynamics and fl uid balance, thus aff ecting the composition of inner-ear fl uid in patients with Meniere’s disease. Furthermore, a complete mastoidectomy is not a placebo treatment, since this procedure might have inadvertently decompressed the tight Trautmann’s triangle and improved endolymphatic sac aeration and function. We have shown that the main feature of ESE surgery is the decompression of the sigmoid sinus, which leads to improved endolymphatic sac decompression.80 The most important part of ESE surgery is a successful complete mastoidectomy, which was off ered to patients in the placebo group in Thomsen’s study.

Ostrowski and Kartush84 investigated the long-term effi cacy of ESE-vein decompression surgery on patients with classic Meniere’s disease. The investigators reported a 72% long-term improvement in control of vertigo and concluded that benefi cial long-term outcome of this method supports its continued use as a fi rst-line treatment option in patients with intractable Meniere’s disease. Huang’s study85 of more than 3000 cases indicated a 90% chance of achieving complete or substantial control of vertigo in the short term (over 3 years).

Revision of endolymphatic sac surgery has been done on patients who have initial successful results after primary endolymphatic sac surgery. In 1988, we reported an incidence of revised cases of endolymphatic sac surgery of 7%.86 A further study by Paparella87 also corroborated that revision of this procedure is rarely

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needed and that ESE surgery has excellent results in control of recurrent attacks of vertigo in patients who have initial successful results from the primary surgery—complete control of vertigo was reported in 21 of 22 patients who underwent revision of ESE, with the remaining patient needing a vestibular neurectomy.

The safety of ESE surgery has also been established in elderly patients with Meniere’s disease.88 In 62 patients aged 65 years and older who underwent a total of 78 ESE surgeries, no signifi cant complications, sequelae, or perioperative deaths were recorded. The investigators recorded a prevalence of 1·6% of major complications, mainly cardiac arrhythmia. 77% of the elderly patients undergoing ESE had complete resolution of their vertigo for up to 2 years after surgery.

Vestibular nerve sectionJackler and Whinney’s review89 of surgery on the VIII cranial nerve indicated signifi cant fl uctuations in the degree of interest in vestibular nerve section during the 20th century. In the mid-1900s, section of the VIII nerve that was made common practice by Dandy90 was largely replaced by the endolymphatic sac procedure and labyrinthectomy.91 There was renewed interest in vestibular nerve section after House introduced the middle-fossa vestibular neurectomy in 1961.92 Investi-gators such as Fisch and Glasscock and col leagues93–95 modifi ed House’s middle-fossa approach to include inferior vestibular neurectomy for improved control of vertigo. Silverstein and Norrell96,97 described the fi rst retrolabyrinthine vestibular nerve section for Meniere’s disease. However, the retrolabyrinthine approach proved to be diffi cult because of the forward location of the sigmoid sinus and diffi culty in accessing the lateral aspect of the internal auditory canal for patients who had poor cleavage between the vestibular and cochlear nerves.

Silverstein and others98 modifi ed the vestibular nerve section to include a retrosigmoid/internal auditory canal approach, in 1985. This modifi cation proved to be eff ective in exposure of the vestibule-cochlear cleavage and in providing access to the cerebellopontine angle, and later this technique replaced the retrolabyrinthine method. Silverstein proposed a combined retrosigmoid-retrolabyrinthine vestibular nerve section that ensured a complete cure of vertigo in about 85% of patients and a substantial improvement in another 7%.99 Preservation of hearing remained excellent, with only 20% of patients showing a slight change in levels of hearing compared with levels before surgery, and up to 4% showing signifi cant hearing loss. Combined retrolabyrinthine/retrosigmoid vestibular nerve section has remained the gold standard in vestibular neurectomy procedures.99

However, at most otological centres, vestibular neurectomy is undertaken far less now than it was in the mid-1980s. Eff ective medical treatment and dietary control, combined with intermittent use of oral steroids and middle-ear perfusion of steroids or gentamicin has

substantially reduced the number of patients with intractable vertigo needing vestibular neurectomy.

Vestibular rehabilitationVestibular rehabilitation is a form of physical therapy designed to improve vestibular function and mechanisms of central adaptation and compensation. It can be quite successful in helping patients prevent the signifi cant sequelae of vestibular loss and vertigo; vestibular adapta-tion exercises to prevent falls have proven to be particularly eff ective. However, the treatment is only successful for patients who have stable, non-fl uctuating vestibular loss.100

ConclusionMeniere’s disease continues to affl ict hundreds of thousands of patients every year on a global scale. Patients of all ethnic and racial backgrounds have been affl icted with this chronic illness. It is true that we still do not have a cure for this disease, as with many other illnesses in medicine. However, substantial improvements have been made over the centuries in dealing with this illness, especially in the past decade, and several safe and eff ective medical and surgical therapies are now available to help patients cope with the disorder’s sequelae. Physicians treating patients who have Meniere’s disease need to remain optimistic and convey a positive attitude when dealing with patients affl icted with this illness.Confl ict of interest statementWe declare that we have no confl ict of interest.

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