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MENIERE’ DISEASE PATHOGENESIS & MANAGEMENT History 1861: Prosper Meniere described a syndrome characterized by deafness, tinnitus, and episodic vertigo. Linked this condition to a disorder of the inner ear. Knappin (1871) :theorizes dilatation of membranous Labyrinth. Dr George Portmann (1926) :Documented first endolymphatic sac drainage surgery for the treatment of vertigo in meniere’s ds. ‘AURICULAR GLAUCOMA’ Dandy (1928) : Treated 9 pts of meniere’s ds by sectioning the 8th nerve. Hallpike and Cairns (1938) : First described Endolymphatic hydrops, the principal pathological feature of Meniere’s ds via temporal bone histology. American Academy of Opthalmology & Otolaryngology Committee on Equilibrium (1972) described Meniere’s ds : “A disease of membranous inner ear characterized by deafness, vertigo & usually tinnitus, which has as its pathologic correlate hydropic distension of the endolymphatic system” AAO-HNS Committee on Hearing and Equilibrium revised definition in 1995. Meniere’s is diagnosed by Vertigo Spontaneous, lasting minutes to hours Recurrent, must have 2 episodes > 20 min. Nystagmus during episodes Hearing loss :SNHL must be documented at least 1 occasion Avg (250, 500, 1000) 15 dB < Avg (1000, 2000, 3000) or Avg (500, 1000, 2000, 3000) 20 dB > than other ear For bilateral disease Avg (500, 1000, 2000, 3000) > 25 dB in the studied ear Tinnitus No guidelines Aural pressure No guidelines AAO-HNS : American Academy of Otolaryngology-Head & Neck Surgery Possible Meniere's disease Episodic vertigo of the Meniere's type without documented hearing loss, or Sensorineural hearing loss, fluctuating or fixed, with dysequilibrium but without definitive episodes Other causes excluded Probable Meniere's disease One definitive episode of vertigo Audiometrically documented hearing loss on at least one occasion Tinnitus or aural fullness in the treated ear Other causes excluded. Definite Meniere's disease Two or more definitive spontaneous episodes of vertigo 20 minutes or longer Audiometrically documented hearing loss on at least one occasion Tinnitus or aural fullness in the treated ear Other cases excluded Certain Meniere's disease Definite Meniere's disease, plus histopathologic confirmation Functional Level Scale Regarding my current state of overall function, not just during attacks (check the ONE that best applies): 1. My dizziness has no effect on my activities at all. 2. When I am dizzy I have to stop what I am doing for a while, but it soon passes and I can resume activities. I continue to work, drive, and engage in any activity I choose without restriction. I have not changed any plans or activities to accommodate my dizziness. 3. When I am dizzy, I have to stop what I am doing for a while, but it does pass and I can resume activities. I continue to work, drive, and engage in most activities I choose, but I have had to change some plans and make some allowance for my dizziness. 4. I am able to work, drive, travel, take care of a family, or engage in most essential activities, but I must exert a great deal of effort to do so. I must constantly make adjustments in my activities and budge my energies. I am barely making it. 5. I am unable to work, drive, or take care of a family. I am unable to do most of the active things that I used to. Even essential activities must be limited. I am disabled. 6. I have been disabled for 1 year or longer and/or I receive compensation (money) because of my dizziness or balance problem. Staging of Hearing Loss in Definite/Certain Meniere’s: Stage Four Tone Average dB 1 ≤ 25 2 26-40 3 41-70 4 >70 Staging is based on the four-tone average threshold at 500,1000,2000,3000 Hz of the worst audiogram during the interval 6 mths before treatment. Vertigo control Numerical Value Class 0 A 1 to 40 B 41 to 80 C 81-120 D >120 E Secondary Treatment F Numerical value= (x/y) ×100 X= Av. no of definitive spells/month for the 6 mths 18-24 mths after therapy Y= Av. no of definitive spells/month for the 6 mths after therapy Prevalence: varies widely. 50-200/ 100,000 Frequency of bilateral disease : 2-78% (arenberg,1980) Family tendency : up to 20% (paparella,1985) ? Aberration in chromosome 7 - Genetic transmission is variable & inheritence is multifactorial. Age & Sex disrtibution peak incidence:40-50yr 4-90 yr F:M :: 3:2 1:1 (arenberg,1980) Physiology Perilymph – Similar in composition to CSF Endolymph – Similar in compostion to ICF High Na+, Low K+ Low Na+ High K+ Believed to be produced in Stria Vascularis Membranous Labyrinth separates the two Difference of 80mV in charge No difference in pressure Physiology Production and flow of Endolymph - Theories Longitudinal – produced in membranous labyrinth, flows to endolymphatic sac, then to dural venous sinuses Diffuse – produced and absorbed along the membranous labyrinth Periodic Flow – endolymph flows only with changes in volume or pressure Andrews, JC, Intralabyrinthine fluid dynamics: Meniere disease 12(5) Oct 2004 pp408-412 Pathophysiology What causes hydrops? Obstruction of endolymphatic duct/sac Alteration of absorption of endolymph Immunologic insult to inner ear Elevated levels of IG’s in endolymph Pathophysiology Endolymphatic hydrops leads to distortion of membranous labyrinth Normal membranous labyrinth Dilated membranous labyrinth in Meniere's disease (Hydrops) Pathophysiology Build up in pressure may lead to microruptures of membranous labyrinth (Minor et al) Ruptures are confirmed by various histologic studies May responsible for episodic nature of attacks Healing of ruptures may account for return of hearing Review Article: Minor, Lloyd et al, Meniere’s Disease, Current Opinion in Neurology 17(1) Feb2004 Pathophysiology Hydrops role in causation of Meniere’s is not entirely clear Rauche et al 1998 – Study of 19 temporal bone histologies with hydrops13/19 patients with hydrops by histology showed Meniere’s symptoms 6/19 showed no Meniere’s symptoms Rauch SD, et al Meniere’s syndrome and endolymphatic hydrops: double blind temporal bone study. Ann Otol Rhinol Laryngol 1989; 98:873-883 Aetiological factors Meniere’s disease : 1. 7. Genetic Anatomical Traumatic Viral infection Allergy Autoimmunity Psychosomatic & personality features. Secondary endolymphatic hydrops : 1. Developmental insult Abnormal metabolic & endocrine states Syphilis Chronic otitis media Viral infections Autoimmunity Otosclerosis Abnormal fluid balance Leukemia 2. 3. 4. 5. 6. 2. 3. 4. 5. 6. 7. 8. 9. Genetic : possible locus lying between the HLA-C & HLA-A loci on the short arm of chromosome 6.(Xenellis et al 1986) HLA-DR2 locus (Koyama et al.1993) Anatomical : small vestibular aqueduct. (Clemis et al.1968) Smaller endolymphatic sac & duct. (Tanioka et al 1992) Trauma : may produce biochemical dysfunction in the cells of the membranous labyrinth or cause release of debris into the endolymph. Viral infections : Damage to endolymphatic sac & duct by viral infection. (Schuknecht,1986) Neurotropic viruses are more likely offenders. HSV type I Group specific protein of enterovirus.VP1 Role of Allergy High incidence of associated allergy in pts of meniere’s ds.(Pulec.1972) Both food & inhalent allergy were implicated. Relief in symptoms with immunotherapy in 62% cases. (Derebery et al.1992) Autoimmunity Immunological abnormalities noted. Endolymphatic sac capable of generating a humoral or cellular immune response. Igs seen deposited in walls & luminal fluid of endolymphatic sacs of patient. ↑ed serum Ig, ESR, complements in 16% cases.(Suzuki et al 1992) ↑ed circulating immune complexes (Brookes.1986) Antibodies against type-2 collegen (tomada et al.1993) What damage is done by Meniere's Disease? 1. Hair cell death: Repeated attacks of Meniere's kills hair cells in the inner ear. Frequently resulting in unilateral functional deafness. Cochlear (hearing) hair cells are the most sensitive. What damage is done by Meniere's Disease? 2. Mechanical changes to the ear. Dilation of the utricle and saccule. The saccule may dilate so that in later stages, it is adherent to the underside of the stapes footplate. mechanical disruption and distortion of normal inner ear structures may result in the gradual onset of a chronic unsteadiness. Variants of meniere’s disease Cochlear hydrops : only cochlear symptoms. Vertigo absent. Vestibular hydrops : cochlear function normal Lermoyez syndrome :characterised by attacks of tinnitus and diminished hearing/deafness followed by vertigo after which hearing improves. Otolithic crisis of Tumarkin dangerous variant causing abrupt fall. attributed to sudden mechanical deformation of the otolith organs(utricle and saccule), causing a sudden activation of vestibular reflexes. Often surgical management required. Physical Examination During an acute attack severe vertigo diaphoresis and pallor hypertension, tachycardia, tachypnoea spontaneous nystagmus with fast component towards the affected ear Physical Examination A complete neurologic examination is necessary. New-onset vertigo might be an early sign of stroke, migraine, or brainstem compression. Romberg test reveals significant instability during acute attacks. Hennebert sign is nystagmus owing to applied pressure in the external auditory canal. Tullio phenomenon is sound-induced vertigo or nystagmus or both. Historically associated with syphilis but has been described in Ménière disease Dix-Hallpike positional test Lab Studies Complete blood cell count Electrolyte level Sedimentation rate C-reactive protein Urinalysis Thyroid panel Fluorescent treponemal antibody Hearing Evaluation Audiogram typical of early Meniere's disease on the right side . Audiogram typical of middle-stage Meniere's disease on the right side . Hearing Evaluation •Early ds : characterstic pattern is of one of a low frequency flucuant hearing loss. •Second early pattern is one of the low frequency hearing loss in concert with a high frequency hearing loss, resulting in a ‘Inverted V’ shape audiogram. •Downward sloping less likely. •Dysacusis : sounds are perceived to have an abnormal tinny nature. •Displacusis : A tone of particular frequency may appear normal in one ear & of higher pitch in another. Speech audiometry : Discrimation score is usually 55-85% between attacks. much impaired during & immediately after an attack. SISI test (short increment sensitivity index): >70% (Normal<15%) Recruitment test is positive. Glycerol dehydration test Dehydrating agent. 1.5ml/kg with equal amt of water Audiogram & speech discrimination scores before & 2 hr after ingestion Positive test : Improvement of 10 db in 2 or more adjacent octaves or gain of 10% in discrimination score. Transtympanic electrocochleography (ECOG) Specifically detects distortion of the neural membranes of the inner ear. This is presumably due to perilymph pressure fluctuations and can show evidence of cochlear involvement. Transtympanic electrocochleography (ECOG) Silver ball electrode placed on the promontory. Sounds stimuli are produced from a loudspeaker in earphones usually in form of clicks. An averaging computer is used to average out the background electrical activity & produce the clear electrophysiological potentials. Summating potential : complex, multicomponent response representing the sum of various electrical event occuring within the cochlea. Evoked action potential : compound action potential representing the synchronus firing of multiple cochlear neurons derived mainly from the basal turn of cochlea. Typical transtympanic ECoG findings in meniere’s ds are : Small distorted cochlear microphonic Widened AP/SP waveform. SP/AP >.45 Electronystagmography (ENG) Test of the inner ear function (particularly the semicircular canals). Tests central and peripheral function and can help localize the site of lesion. Reduced vestibular response in the affected ear in menieres, although response may be increased secondary to an irritative lesion. Auditory brain stem evoked responses Otoacoustic emissions VEMP Imaging Studies MRI : to detect abnormal inner ear anatomy, masses, and lesions such as multiple sclerosis and Arnold-Chiari malformations. CT : to detect dehiscence of the superior semicircular canals, widened cochlear and vestibular aqueducts, and subarachnoid hemorrhage. Differential Diagnosis Benign Positional Vertigo Headache, Migraine Hypothyroidism and Myxedema Coma Labyrinthitis Multiple Sclerosis Otitis Media Stroke, Ischemic Subarachnoid Hemorrhage Temporal Lobe Epilepsy Toxicity, Salicylate Transient Ischemic Attack Vestibular Neuronitis TREATMENT “Natural History” Silverstein et al (1989) 1985 AAO criteria Studied a group of patients who failed medical treatment and declined surgery Vertigo Hearing 57-60% complete control in 2 years 71% complete control at 8 years (average) 43% unchanged in unoperated patients 45% unchanged in operated patients Conclusion “Given sufficient length of follow-up, a large proportion of patients will have a spontaneous ‘cure’ of vertigo.” Placebo Effect Multiple studies of both medical and surgical therapies have shown high levels of improvement with placebo. Torok (1977) “… the ultimate results, whatever course of medication or surgery was applied. Recovery varies from about 60% to 80% …improved are 20% to 30% and …failure is between 10% and 25%.” Jongkees (1964) “Result of treatment depends more upon the personality of the doctor and the belief he has in his treatment.” Medical Management Acute Therapy Maintenance Therapy Medical Management Medical Management Maintenance Therapy No conclusive studies show efficacy of drugs intended to alter disease course of Meniere’s Medical Management Diuretics and Salt restriction ? Alter fluid balance in inner ear leading to depletion of endolymph Osmotic Diuretics (Urea, Glycerol) Unpleasant taste Have been consistently shown to reduce symptoms in a proportion of patients, but the effects only last for a few hours Objective data includes alteration of the SP:AP ratio on electrocochleography Acetazolamide IV adminisration has been shown to worsen hydrops and hearing loss (Brookes) Oral administration may improve hydrops Side effects encountered include metabolic acidosis and renal calculi Vasodilators Vasodilators Thought to work by decreasing ischemia in the inner ear and allowing better metabolism of endolymph Betahistine Papaverine, isoxpurine, nylidrin, dipyradamole, amyl nitrate, nitro glycerine, nicotinic acid, Co2 Beta histine Betahistine A popular choice studies showing decreased vertigo partial agonist against cerebral H1 receptors potent H3 receptor antagonist increases histamine release Side effects :worsening asthma, GI upset. Water Therapy Naganuma et al (2006) Prospective study Patients: 18 test, 29 control Test group: 35 mL/kg/day water x 2 years Control group: Diuretics and salt restriction Timeline: 2 years Results: Low frequency PTA’s significantly improved in the water therapy group Vertigo resolved in both groups Laryngoscope. 116(8), August 2006, pp 1455-1460 Meniett Device Transtympanic “Micropressure” Treatment Treatment self-administered Requires a tympanostomy tube Meniett Device Principle :The excess fluid of the inner ear, can be restored to normal levels by the application of low-pressure pulses to the outer ear which are then transmitted to the inner ear through an opening in the eardrum. Each treatment is three 1minute cycles Applies intermittent, alternating pressure 0-20 cm H20 Meniett Device Gates GA, Green JD. (2002) Design: Prospective study, 10 patients, 3-10 months Criteria: “active symptoms of vestibular or cochleovestibular hydrops” Vertigo 90% Complete control (presumed level A) 10% with “50%” reduction (response level C) Functional Level Improved 1-3 levels in all cases Problems Tube otorrhea, blockage, extrusion Recurrence of disease after therapy cessation Meniett Device Thomsen et al (2005) Prospective, randomized, placebo control trial of “overpressure” device in 40 patients Placebo device did not generate pressure AAO-HNS 1995 standards were used Definite Meniere’s patients only Functional levels monitored Vertigo Both groups had large decreases in the number of attacks No statistical significance between active and placebo, although “there was a trend … toward a reduction” Significant improvement over the placebo was found in patient perception of vertigo control. Functional Level Statistical significance in the improvement of functional level between placebo and overpressure Intratympanic Therapy Intratympanic Therapy Goal is to maximize local effects in inner ear while minimizing systemic effects Intratympanic Ablation Fowler (1948) and Schuknecht (1957) established role of aminoglycoside therapy. Streptomicin used initially Vertigo eliminated in all patients Profound hearing loss in all patients Gentamicin treatment now preferred Theoretical targets of therapy are Dark cells of the stria vascularis Planum semilunatum of the semicircular canals Higher doses destroy the hair cells of the cochlea Intratympanic Gentamicin Gentamicin is preferred because it is more vestibuloselective Side effects can include: Many methods of delivery exist Temporary imbalance or nystagmus Hearing loss Tinnitus Injection Gelfoam placement Microwick Multiple dosing schedules have been proposed Low dose Weekly Multiple Daily Continuous Titration Intratympanic Gentamicin Low dose therapy Harner et al (2001) Retrospective study Patients: 51 Dosing: 1 dose of 40mg/mL injection, re-evaluated at 1 month and given another if needed Vertigo: 86% Class A/B (2 yrs) Hearing PTA minimal change SRT some drop Authors claim better hearing preservation Harner, Stephen et al: Long-term follow-up of transtympanic gentamicin for Meniere’s Syndrome. Otology & Neurotol 22:210-214, 2001 Intratympanic Gentamicin Ablation via Multiple Daily Dosing Jackson and Silverstein – Study on 92 patients who underwent myringotomy and wick placement through to round window niche. Pts. self-administered gentamicin drops TID until 100% reduction on ENG of vestibular response 85% relief of vertigo, 67% improvement in aural pressure 36% hearing loss Jackson, LE; Silverstein, H: Chemical perfusion of the inner ear. Otolaryngol Clin North Am 2002, 35:639-653 Intratympanic Gentamicin Titration Therapy Martin and Perez 2003 (prospective study, n=71) Serial daily injections of buffered (pH 6.4) 26.7mg/cc gentamicin solution via 27 gauge needle into middle ear Injections repeated until vestibular symptoms developed (spontaneous or evoked nystagmus) At 2 years, 69% had Class A vertigo control, 14.1% had Class B 32.4% had hearing loss Martin E, Perez N: Hearing loss after intratympanic gentamicin therapy for unilateral Meniere’s Disease. Otol Neurotol 2003, 24:800-806 Intratympanic Gentamicin Other methods of delivery Weekly administration Single dose of gentamicin once a week for four treatments Continuous administration Microcatheter delivery of gentamicin using a continuous perfusion method Results in extremely variable amount of gentamicin delivery Better perfusion techniques may be needed Intratympanic Gentamicin Chia et al performed a meta-analysis of different modalities of application in 2004 Class A or B Vertigo Control Chia, Stanley H, et al Intratympanic Gentamicin Therapy for Meniere’s Disease: a MetaAnalysis. Otology&Neurotol 25(4) July 2004 pp 544-552 Intratympanic Gentamicin Hearing loss was greatest for multiple daily dosing Hearing loss was least for titration therapy Intratympanic steroid An attempt to control symptoms without vestibular ablation least invasive, least destructive surgery Intratympanic steroid Barr et al (2001) 21 patients Intratympanic injections of 4 mg/mL dexamethasone over a period of 4 wks Complete relief of vertigo 11 /21 (52%) at 3 months 9 /21 (43%) at 6 months. Laryngoscope,111(12), 2001, pp 2100-2104 Surgical Therapy Reserved for medical treatment failures and is otherwise controversial. Surgical procedures are divided into 2 major classifications as follows: Destructive surgical procedures Nondestructive surgical procedures surgical procedures Cont’d Destructive surgical procedures Rationale to control vertigo: Fluid pressure accumulation within the inner ear→ temporary malfunction and misfiring of the vestibular nerve. → vertigo. Destruction of the inner ear and/or the vestibular nerve prevents these abnormal signals. As long as the opposite inner ear and vestibular apparatus function normally, the brain eventually will compensate for the loss of one labyrinth. Destructive surgical procedures Cont’d Problems with destructive procedures: Destruction of one inner ear depends on the adequate function of the opposite ear. Meniere’s disease can be bilateral (7-50%), in which case this method is contraindicated. destruction of the balance portion carries a high risk of hearing loss. irreversible and reserved for severe cases. surgical procedures Cont’d Nondestructive surgical procedures: Directed toward improving the state of the inner ear Less invasive Do not preclude the use of other treatment modalities. 1. 2. 3. 4. endolymphatic sac decompression or shunt vestibular nerve section Sacculotomy Ultrasonic destruction of vestibular labyrinth Endolymphatic Sac Surgery Purported to address the site of obstruction causing hydrops 4 types: Decompression – removal of bone around the sac Shunting – placement of synthetic shunt to drain endolymph into mastoid Drainage – incision of the sac to allow drainage Removal of sac Endolymphatic Sac Surgery Jens Thomsen et al (1981) Double-blinded placebo-control study Patients: 30 Procedure: Cortical mastoidectomy without decompression vs. endolymphatic shunt placemen Results: Both surgery and placebo showed statistically significant improvements over pre-treatment status Physician evaluation showed good results in 73% of shunts vs. 80% of placebo Patient subjective evaluation showed good results in 73% of shunts vs. 67% of placebo Conclusion: Impact of surgery on the symptoms of Meniere’s disease is nonspecific and unrelated to the actual shunt procedure.” Endolymphatic Sac Surgery Silverstein et al (1989) Compared different surgical interventions to unoperated Meniere’s patients Patients: 89 operated ears, 50 unoperated ears Vertigo Hearing No difference between ELS and “natural history” Nerve section significantly better than no surgery ELS procedures resulted in 40% complete control vs. 91-100% complete control in nerve section patients No difference in operated (all types) vs. unoperated ears Conclusion Endolymphatic sac shunt surgery should not be recommended to patients with Meniere’s disease. Vestibular Nerve Section Direct method of functional vestibular ablation Single step procedure Approaches: Middle Fossa Retrolabyrinthine/Retrosigmoid Transcanal Complications Damage to facial nerve Damage to cochlear nerve CSF leak (about 13%) Vestibular Nerve Section Hillman et al (2004) Retrospective comparison of VNS to IT Gentamicin High level of vertigo with minimal hearing change Low rate of complications (12.8% CSF leak) Conclude that both Gent and VNS are appropriate alternatives Labyrinthectomy Useful in patients with no serviceable hearing and those who cannot tolerate intracranial procedure Similar in efficacy to vestibular nerve section Dietary Modifications Distribute food and fluid intake evenly throughout the day and from day to day. Avoid eating foods or fluids which have a high salt content. Consult with a nutritionist to establish a rigid salt-restricted diet (1.5 g sodium per day). Drink adequate amounts of fluid daily. Avoid caffeine-containing fluids and foods (such as coffee, tea and chocolate). Limit alcohol intake. Avoid foods containing MSG (monosodium glutamate). prepackaged food products. Avoid aspirin,ibuprofen or naproxen Activity: Endolymphatic hydrops does not preclude regular activity. Exercise is recommended in moderation. Because of the unpredictable nature of the disease, balance-intensive, dangerous tasks (eg, especially climbing ladders) should be avoided. Overview Acute Therapy Non-invastive medical treatments Lifestyle modification Alternative options Alternative Therapies Meniett Non-Destructive Therapy Diuretics Salt Restriction Vasodilators ? Water Therapy Long-Term Stabilization Vestibular Suppressants Medical: IT Steroids Surgical: Mastoid shunt Intratympanic Steroid Therapy Destructive Therapy Medical: IT Gentamicin Surgical Nerve section Labyrinthectomy Shunt surgery Intratympanic Gentamicin Therapy Surgical Ablation Nerve Section Labyrinthectomy Disease progression Most bothersome in early stages. In later stages, the hydrops fills the vestibule so completely that no further room is available for pressure fluctuation and the vertigo spells disappear. Acute attacks are replaced by constant imbalance and progressive hearing loss. Medical Management Diuretics and Salt Restriction Ruckenstein et al evaluated data from two double blind studies Showed no difference in Diuretics vs. placebo Ruckenstein M.J., Rutka J.A. & Hawke M. (1991) The treatment of Meniere's disease: Torok revisited. Laryngoscope101, 211-218 Normal electrocochleogram from the tympanic membrane to clicks presented in alternating polarity at 80 dB HL. The amplitudes of the Summating Potential (SP) and Action Potential (AP) can be measured from peak-to-trough (left panel), or with reference to a baseline value (right panel). Ginkgo Biloba Extract 70 patients with vertiginous syndrome 3 month therapy Ginko group :47% Placebo group :18% Prognosis Variable, since the disease pattern of exacerbation and remission makes evaluation of treatment and prognosis difficult to predict. In general, meniere’s symptoms tend to stabilize spontaneously with time. With regard to vertigo, about half of patients stabilize over several years. Patients tend to "burn out" over time and with residual poor balance and hearing.