Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Dr T Balasubramanian MS DLO www.drtbalu.com 1 Meniere’s disease is defined as a symptom complex associated with: 1. Roaring tinnitus 2. Sensorineural hearing loss (Low frequency) 3. Vertigo (episodic) 4. Fullness of the ear 5. These symptoms are associated with dilated membranous labyrinth filled with endolymph www.drtbalu.com 2 1. 2. 3. 4. 5. 1747 – Antonio Scarpa described anatomy of membranous labyrinth 1861 – Prosper Meniere described the classic features of Meniere’s disease & attributed it to labyrinthine causes 1871 – Knappin theorized that dilated membranous labyrinth to be the cause of this disorder 1927 – Guild described endolymphatic ciruclation 1938 – Hallpike and Portmann described pathology of Meniere’s disease by studying temporal bones. www.drtbalu.com 3 1. 2. 3. 4. 5. 150 years have passed since this syndrome was described Amount of literature accumulated has virtually doubled Only consensus reached so far is that its cause is multifactorial Not all individuals with histological features of Meniere’s disease manifested the classic clinical features (? Unknown factors protecting the individuals) Surgical destruction of sac ameliorates symptoms. (? What role does sac play exactly in endolymphatic circulation) www.drtbalu.com 4 1. 2. 3. Inner ear contains two types of fluids (perilyimph and endolymph separated by membranous labyrinth. Perilymph is similar in composition to CSF (Containing high Na and low K ions) Endolymph similar in composition to intracellular fluid (Containing low Na and high K concentration). It is secreted by stria vascularis www.drtbalu.com 5 Duct begins at ductus reuniens Duct is a single lumen tube about 2 mm long The duct narrows at the isthmus which lies at the level of vestibular aqueduct www.drtbalu.com 6 1. 2. 3. Secretory function Absorptive function Immune / defense function www.drtbalu.com 7 1. 2. 3. 4. Aquaporins Glycoproteins like Saccain Endolymph Glycoproteins act as a driving force for longitudinal flow www.drtbalu.com 8 1. 2. 3. Longitudinal flow Radial flow Dynamic flow www.drtbalu.com 9 1. 2. 3. 4. Was first proposed by Guild Striavascularis is the principal source This is a slow process Elimination occurs at the endolymphatic sac level www.drtbalu.com 10 1. 2. First proposed by Lawrence This is a combination of both longitudinal and radial flow patterns www.drtbalu.com 11 1. 2. 3. This is active process (energy consuming) Production occurs from dark vestibular cells & planum semilunatum Absorption occurs at the striavestibularis www.drtbalu.com 12 1. 2. 3. This is a small membranous bulb located where the endolymphatic duct enters the vestibule This is where the volume of circulating endolymph is monitored Monitoring the volume of endolymph is not possible by sac because it will be interfered by CSF pressure and pressure exerted by lateral sinus www.drtbalu.com 13 www.drtbalu.com 14 1. 2. 3. 4. 5. Composition of endolymph is maintained by stria vascularis by controlling the influx of water Normally endolymph is a biological puddle with very little radial / longitudinal flow Only under exceptional circumstances like increased endolymphatic fluid volumes does radial / longitudinal movement towards sac occurs Under normal circumstances radial flow alone is sufficient to maintain endolymph fluid balance and the longitudinal flow due to saccmechanics is not necessary The longitudinal flow is restricted by the isthmus portion of the duct which acts like the constriction seen in the hour glass www.drtbalu.com 15 www.drtbalu.com 16 www.drtbalu.com 17 www.drtbalu.com 18 1. 2. 3. 4. Small amounts of excess endolymph can be cleared by radial flow Larger volumes need longitudinal flow for their clearance Endolymphatic sinus temporarily accommodates excess endolymph till the sac is ready for it Endolymphatic valve of Bast isolates pars superior and prevents endolymph from draining out of the utricle www.drtbalu.com 19 1. 2. 3. 4. 5. 6. Genetic causes Infection Otosclerosis Trauma (physical / acoustic) Syphilis Miscellaneous – Allergy, tumors, leukemia and autoimmune disorders www.drtbalu.com 20 1. 2. 3. 4. 5. Classical Meniere’s disease Vestibular Meniere’s disease – vestibular symptoms and aural pressure Cochlear Meniere’s disease – cochlear symptoms and aural pressure Lermoyez syndrome – Reverse Meniere’s Tumarkin’s crisis – Utricular Meniere’s www.drtbalu.com 21 This is a variant of Meniere’s disease. It is characterized by sudden sensori neural hearing loss which improves during or immediately after the attack of vertigo. www.drtbalu.com 22 This variant is characterized by abrupt falling attacks of brief duration without loss of consciousness. This is caused due to an enlarging utricle due to excess endolymphatic volume. Utricular crisis is used to indicate this condition. In the later disease stages the valve of Bast remaining patent may cause sudden drainage of endolymph from the utricle due to longitudinal flow resulting in these drop attacks www.drtbalu.com 23 Roughly 1 in 1000 individuals are affected Constitutes 10% of all patients attending vertigo clinic Female preponderance Rare in children under the age of 10 Commonly begins between 4th and 5th decades of life Bilateral Meniere’s syndrome is seen in 5% of these patients www.drtbalu.com 24 1. 2. 3. 4. Endolymphatic hydrops causes distortion of membranous labyrinth Pressure building up in the scala media may cause mirco ruptures of membranous labyrinth This would account for the episodic nature of the attacks Healing of these ruptures causes resolution of the disorder www.drtbalu.com 25 1. 2. 3. 4. 5. Episodic vertigo rotatory in nature Ipsilateral hearing loss Aural fullness Roaring tinnitus Diplacusis www.drtbalu.com 26 1. 2. 3. Stage I – Patient has solely cochlear symptoms Stages II – IV – Patients have progressively more cochlear and vestibular symptoms Stage V – End stage Meniere’s disease (dead ear) www.drtbalu.com 27 1. 2. 3. Irritative nystagmus during the first 20 mins of attack Paralytic nystagmus follows Later recovery nystagmus starts www.drtbalu.com 28 Possible Meniere’s disease: Episodic vertigo of Meniere’s type without documented hearing loss Fluctuating hearing loss with disequilibrium but without definite episodes Probable Meniere’s disease: One definitive episode of vertigo Audiometrically documented hearing loss at least during one attack Definitive Meniere’s disease Two or more definitive episodes of spontaneous vertigo one atleast lasting for 20 mins. Audiometrically documented hearing loss at least on one occasion Tinnitus and aural fullness in the treated ear www.drtbalu.com 29 Sensori neural hearing loss combined with: Tinnitus now / in the past Vertigo attacks (at least two present now or in the past) Exclusion of other pathology following Groningen protocol Hearing loss: Sensori neural in nature No demonstrable conductive element Hearing loss of 20 dB or more at one of the usually measured audiometric thresholds Vertigo: Paroxysmal rotatory dizziness, accompanied by nausea / vomiting At least two episodes should be reported during a course of illness. One of the attack should last at least for 5 mins In between attacks there may be periods of unsteadiness www.drtbalu.com 30 1. 2. 3. 4. 5. Sensori neural in nature Fluctuating and progressive Affects low frequencies Mild low frequency conductive hearing loss (rare) Profound sensori neural hearing loss (End stage) www.drtbalu.com 31 Roaring in nature Could be continuous / intermittent Non pulsatile in nature Frequency of tinnitus corresponds to the region of cochlea which has suffered the maximum damage www.drtbalu.com 32 1. 2. 3. 4. This is abnormal growth in the perceived intensity of sound This is usually positive in patients with Meniere’s disease ABLB is the test used to look for the presence of recruitment This test is really time consuming www.drtbalu.com 33 1. 2. 3. Increased summating potential / action potential ratio. 1:3 is normal Widened summating potential / action potential complex. A widening of greater than 2 ms is significant Small distorted cochlear microphonics www.drtbalu.com 34 1. 2. 3. 4. 5. Not mandatory for diagnosis of Meniere’s disease Caloric test is still performed It is low frequency stimulation (0.003 Hz) of lateral canal Caloric asymmetry will point to the diseased ear 20% difference between the two ears (Jongkee’s formula) is significant www.drtbalu.com 35 1. 2. 3. 4. 5. 6. 7. 8. Vestibular evoked myogenic potential Measures the relaxation of sternomastoid muscle in response to ipsilateral click stimulus Brief high intensity ipsilateral clicks produce large short latency inhibitory potentials (VEMP) in the toncially contracted Ipsilateral sternomastoid muscle This test is due to the presence of vestibulo collic reflex Afferent arises from sound responsive cells in the saccule, conducted via the inferior vestibular nerve. Efferent is via vestibulo spinal tract Normal responses are composed of biphasic (positive-negative) waves VEMP reveals saccular dysfunction www.drtbalu.com 36 1. 2. 3. 4. Glycerol Frusemide Isosorbide Tests are positive if there is pure tone improvement of 10dB or more at two / more frequencies between 200-2000Hz www.drtbalu.com 37 1. 2. 3. 4. 5. 6. 7. First introduced by Klockhoff and Lindblom – 1966 Glycerol is administered in doses of 1.5 mg/kg body wt in empty stomach Serum osmolality should increase at least by 10 mos/kg Side effects include Headache, Nausea, vomiting, drowsiness PTA is performed 2-3 hours after administration False positivity is rare Positivity depends on the phase of the disease www.drtbalu.com 38 1. 2. 3. 4. Dietary management Physiotherapy Psychological support Pharmacological intervention www.drtbalu.com 39 1. 2. 3. Intravenous fluids – dehydration Vestibular suppressants – May delay recovery / rehabilitation process Corticosteroids – May help if tinnitus and deafness are debilitating www.drtbalu.com 40 1. 2. 3. Frustenberg diet 2 grams / 24 hours (restricted salt intake) Life style modification www.drtbalu.com 41 1. 2. 3. 4. 5. Diuretics play a vital role in alleviating acute symptoms This has been in use since 1930’s Thiazide group of drugs are commonly used Frusemide may be used to alleviate acute symptoms Clear scientific evidence is lacking regarding the usefulness of diuretics (cochrane review) www.drtbalu.com 42 1. 2. 3. 4. 5. Cochlear vascular insufficiency has been proposed as one of the mechanism of Meniere's disease Betahistine is supposed to cause vasodilatation of cochlear blood vessels Betahistine has weak H1 agonistic property and considerable H3 antagonist properties It reduces the frequency & intensity of vertigo. Has minimal effect on tinnitus Doesn’t help much with hearing loss (Cochrane review) www.drtbalu.com 43 1. 2. 3. 4. 5. Immune modulating effects Improves fluid dynamics of inner ear due to mineralocorticoid effects Vertigo was controlled on an immediate basis Methylprednisolone has the best effect as it penetrates the round window better Silverstein microwick can be used for intratympanic drug administration www.drtbalu.com 44 1. 2. 3. 4. 5. 6. 7. 8. 9. Isordil ϒ – globulin Urea Glycerol Lithium Anticholinergics – Glycopyrrolate 1-2 mg /day Antidopaminergics – Droperidol 2.5 – 10 mg orally / day Leuprolide acetate – Blocks normal sex hormone production Innovar – A combination of droperidol and fentanyl can be used to suppress vestibular symptoms (can replace endolymphatic sac surgery) 10. Hyperbaric oxygen therapy www.drtbalu.com 45 1. 2. 3. 4. Stress reduction Patient education Hearing aids – can be used to suppress troublesome tinnitus Tinnitus retraining www.drtbalu.com 46 1. 2. 3. 4. 5. 6. 7. Meniett Device Low pressure pulse generator Vibrations are transmitted via external auditory canal Vibrations alter inner ear fluid dynamics by their effects on the oval and round windows Exact mechanism of action is not known It is totally non invasive This device is portable www.drtbalu.com 47 1. 2. 3. 4. 5. Diagnosis should be confirmed Ventilation tube should be inserted Patient should be trained for self administration of the treatment Usually administered thrice a day about 5 mins each time Treatment lasts for 5 weeks www.drtbalu.com 48 1. 2. 3. 4. 5. Classic unilateral Meniere’s disease Intense vestibular / cochlear symptoms Failed medical therapy Over 65 years of age Imbalance / aural fullness / tinnitus after gentamycin treatment www.drtbalu.com 49 1. 2. 3. 4. Perilymph fistula Acoustic neuroma / brain tumor Retrocochlear damage Low pressure hydrocephalus www.drtbalu.com 50 1. 2. 3. 4. Vestibulotoxic effects are put to therapeutic use. Sensation of vertigo reduced while hearing is preserved Streptomycin / gentamycin are predominantly Vestibulotoxic Intratympanic administration is preferred www.drtbalu.com 51 1. 2. 3. 4. 5. 6. 7. 8. Fixed dose protocol is used 40 mg/ml gentamycin is buffered with soda bicarb (pH6.4) final concentration 26.7mg/ml. T tube grommet inserted into the postero inferior quadrant of ear drum. A mcirocatheter is inserted through the grommet 1ml of gentamycin solution is injected into the middle ear cavity via the microcatheter Three injections are given per day in outpatient setting Injections are given for 4 days After injection patient should lie supine with the infiltrated ear up for 30 mins Vertigo usually develops between 2-4 days after cessation of treatment www.drtbalu.com 52 1. 2. 3. Sac enhancement procedure Sac decompression procedure Labyrinthine ablative procedures www.drtbalu.com 53 1. 2. External shunts – Drains the sac into mastoid cavity / subarachnoid space Internal shunts – Drains excessive endolymph into the perilymphatic space (cochleosacculotomy / labyrinthotomy) www.drtbalu.com 54 www.drtbalu.com 55 1. 2. 3. 4. Helpful in treating debilitated patients Involves disruption of osseous spiral lamina Angular pick introduced via round window towards oval window. It will accommodate 3 mm long pick After perforation the pick is withdrawn and the round window is sealed by fat www.drtbalu.com 56 1. 2. 3. 4. 5. Labyrinthectomy Translabyrinthine vestibular neurectomy Retrolabyrinthine vestibular neurinectomy Retrosigmoid vestibular neurinectomy Middle cranial fossa vestibular neurinectomy www.drtbalu.com 57