Presentation on theme: "VERTIGO Robert W. Jensen, M.D., J.D., F.C.L.M. Associate Professor"— Presentation transcript:
1VERTIGO Robert W. Jensen, M.D., J.D., F.C.L.M. Associate Professor Neuro-Ophthalmology & Neuro-OtologyVERTIGO
2What is vertigo? Hallucination (believed) or Illusion (disbelieved) Self (or environmental)MovementFallingSpinningSee-sawDrifting
3What is NOT vertigo Beware the Trap ! Do not say “Dizzy.” LightheadedNauseousWeakAnxiousDiplopiaBlurred visionConfusedFatiguedBeware the Trap !Do not say “Dizzy.”Dizzy can mean almost anything
4The evaluation of dizziness often gets stuck in the mud and goes nowhere! This is because we do not clearly describe exactly what is going on.
5Important Points Does it come in Attacks or Spells? Is it triggered by Movement, Bending, Tilting, Rolling over, Looking up?Which way does the visual world move?Is it better if you lie or sit perfectly still?If you don’t move, does it go away?Is there hearing loss? Ear Pain? Tinnitus?Do you feel faint?Are you nauseous?
6TYPES OF DISEQUILIBRIUM Peripheral labyrinthine diseaseVestibular nerve root diseaseCentral vestibular diseaseHypoglycemiaAnxiety or PanicHypo-perfusionSpinocerebellar degenerationPolyneuropathy or Autonomic Neuropathy
8The bony labyrinth consists of inter-connecting caverns within the petrous portion of the temporal bone.
9Perilymph = Low K (10 mEq)High Na (140 mEq)Within the bony labyrinth is the delicate membranous labyrinth “inner tube.”The membranous labyrinth fills only 25 to 45% of the bony canals.Outside the membranous labyrinth is perilymph fluidInside the membranous labyrinth is endolymph fluidEndolymph = High K (144 mEq)Low Na (5 mEq)
10The endolymph circulates freely throughout the entire labyrinth, including ALL the separate sense organs, including auditory (cochlea) and vestibular (semicircular canals, utricle, and saccule) components.Vestibular and hearing organs:Share the same bath waterAre packed in the same suitcase
11Semi-Circular Canals The canals contain fluid (called endolymph) The canals contain a “wind-vane” called the “cupula” that occludes a swelling called the “Ampulla”Beneath the cupula is the Crista Ampularis that contains the vestibular nerve cells
12Vestibular Nerve fibers Cupula sits atop the Crista Ampullaris as a gelatinous mass that completely occludes the semi-circular canal at the Ampullary swellingKEY FACT:Specific gravity Cupula =Specific gravityEndolymphThis is necessary for the correct calibration of the system.Crista AmpullarisHair cell receptorsVestibular Nerve fibers
13The Cupula extends across the Ampulla, anchored all around. The Cupula deforms or “leans” as the inertia of endolymph presses against it.As the skull (with the canal Ampulla) moves, the endolymph inertia exerts a contrary force on the Cupula, bending it in the opposite direction of the head movement.The degree acceleration of head movement correlates the degree cupula deformation.
14Because the cupula is attached to the canal wall all the way around, gravity has no effect on the cupulaSo the Semi-Circular Canals measure acceleration, NOT gravity or velocityCupulaPerilymphCrista AmpullarisEndolymphVestibular nerve roots
15Hair Cells in the Crista Ampullaris, below the Cupula, are the active sensory detector The “hairs” project into the Cupula and move with the Cupula
16The hair cells have hair-like projections. The tall “hair” is the Kinocilium.The shorter “hairs” are the Stereocilia.The “hairs” are imbedded in the Cupula above. The cell bodies are in that Crista Ampullaris below.
17The Stereocilia mount-up step-wise climbing towards the Kinocilium Stereocilia get progressively longer the closer they approach the kinocilium – like a staircase.The Stereocilia mount-up step-wise climbing towards the KinociliumThe hair cells have a direction or polarity determined by the KinociliumHair cells have 50 to 100 stereocilia but only one kinocilium
18Deflection of the stereocilia towards the Kinocilium excites (depolarizes) the Hair Cell, increasing the firing rate.GOSTOPDeflection of the Stereocilia away from the Kinocilium inhibits (hyperpolarizes) the Hair Cell, reducing the firing rateKinocilia all “point” in one direction. Kinocilia provide orientation.
19If the Cupula bends toward the kinoclium, then the hair cell is excited (depolarized) and sends a nervous impulse (action potential) to the brainstem.If the Cupula bends away from the kinocilium , then the cell is inhibited (hyperpolarized)
20- + Right head turn . . . Kinocilia point the same way in each ear. Endolymph inertia bends stereocilia towards the kinocilia in the right labyrinthEndolymph inertia bends stereocilia away from the kinocilium in the left labyrinth-+Kinocilia point the same way in each ear.
21The central “lake” or “pool” of the labyrinth is the Vestibule, from which we get the word “Vestibular”All of the Semi-Circular Canals drain to the VestibuleThe Cochlea and Endolymphatic duct drain to the Vestibule.Vestibule
22The Vestibule contains the Otolithic Organs called Utricle and Saccule to sense gravity and velocity Semi-CircularCanalThe Macula is the specialized sensory organ of the Utricle and SacculeThe Macula is similar to the Crista Ampullaris. It contains Hair CellsVestibuleUtricle
23The Otolith Organs contain “otoliths” or “otoconia” Otoconia ride atop a gelatinous otolithic membrane in which hair cell stereocilia are imbedded, much like the Cupula of the semi-circular canals.The otoconia or otoliths are calcium carbonate crystals with specific gravity of 2.71
24OtoconiaStereocilia in gelatinous membraneHair Cells
25Stereocilia are polarized toward a centromere or kinocilium basal body remnant Utricle hair cells are polarized toward the macula mid-line or “striola”No KinocliumSaccule hair cells are polarized away from the striola or macula mid-line
26The Utricle is horizontal The Saccule is verticalThe Semi-Circular Canals are both vertical and horizontal
27Contralateral Anterior and Posterior Canals are parallel The Semi-Circular Canals are orthogonal at ~ 90 degrees form each otherThe anterior and posterior canals are 45 degrees lateral to “straight ahead”45The horizontal or lateral SCC tilts upward by about 30 degrees, so is horizontal when you are looking at your path.9045Contralateral Anterior and Posterior Canals are parallel
28Gravity pulls on the otoconia or otoliths. Position changes the gravitational vector.This “drags” the macular membrane and deflects hair cell stereocilia.Otolithic Organs (Saccule and Utricle) detect this position change.
29Gravity has no effect on the semi-circular canals SCC detect angular acceleration alone.If there is no acceleration, then there is no response.The system comes to rest in 90 to 120 seconds.
30Roll Plane Yaw Plane Pitch Plane Turning head to Nodding head left or right “No”Pitch PlaneNodding headForward or backward“Yes”Roll PlaneTilting head to shoulder
31CENTRAL PROCESSING OF VESTIBULAR INFORMATION Vestibular Ocular Reflex (VOR)Adjust eye position for head positionKeeps visual world from ”jumping.”Vestibular Spinal ReflexesAdjust body position for changes in gravity vector.Adjust center of gravity to avoid falling over.
32SUMMARY OF VESTIBULAR FUNCTIONS DETECT AND MEASURE: Rotary Acceleration Velocity and GravityADJUST AND MODULATE:Eye position (stabilize vision)Body position (stabilize posture)
33CLINICAL VERTIGO SYNDROMES The presentation of the dizzy patient …CLINICAL VERTIGO SYNDROMES
34How does vertigo arise?From eye movements! The vestibular system largely exists to adjust eye and body position to compensate for head position in space.When the eyes move, the visual world moves.
36“VESITBULAR NEURITIS” Usually unilateralUsually Horizontal NystagmusObeys Alexander’s LawSlow CNS compensationDuration many weeks to monthsNon-positionalNo discrete attacksNo hearing lossCause UnknownLabel for ignorance: An acute unilateral vestibular dysfunction without auditory or neurological signs.
37“LABYRINTHITIS” Usually unilateral Sometimes ear pain or aural fullnessUsually variable, constant nystagmusNo discrete “spells” or “attacks”Sometimes preceding respiratory illnessDuration many days to several monthsObeys Alexander’s law for nystagmusCause: Unknown“Presumably viral”Label for ignorance: An acute unilateral vestibular dysfunction with some aural symptoms but no neurological signs.
38BENIGN POSTURAL POSITIONING VERTIGO (BPPV) Provoked by movementLatency of 5 secondsDuration of 30 to 90 secondsUsually Cyclorotary nystagmusGeotropic NystagmusRisk factors = aging, traumaNo auditory symptomsNo neurological deficitsUsually self-limitedUsually Posterior SCCSometimes multiple canalsCause : Overwhelmingly “Canalolithiasis;” Only very rarely “Cupulolithiasis”
39AUTO-IMMUNE INNER EAR DISEASE (AIED) Primary inflammatory disorderAsymmetric Progressive SNHLEither bilateral or unilateral,but usually bilateralNon-positional vertigoProgressive if not treatedMeniere’s syndrome at timesPeriarteritis nodosaWegener’s granulomatosisBechet’s diseaseUlcerative colitisSystemic Lupus ErythematosusRheumatoid arthritisCause: Presumably systemic rheumatologic inflammatory disease
40Endolymphatic Hydrops Minimal perilymphspaceMENIERE’S DISEASEEndolymphatic HydropsGreatly SwollenEndolymph SpaceOften unilateralDuration days to weeksTetrad:Fluctuating aural fullnessHissing tinnitusLow Frequency Hearing LossRecurrent bouts of vertigoUp sloping audiogramCause: Unknown -- - Meniere’s disease is an idiopathic wondermentMeniere’s symptoms can be associated with many different conditions
41PERILYMPHATIC FISTULA Abnormal “Leak” of PerilymphBony labyrinthRound WindowOval WindowOften Pressure SensitiveOften Sound SensitiveUsually Auditory SymptomsTinnitusAural fullnessNon-Specific disequilibriumOccasional true vertigoCause: Usually traumatic. Sometimes congenital.Caveat: Usually very difficult to either confirm or exclude
42OTOLITH CRISIS OF TUMARKIN Drop Attacks. Patient remains awakeOften sound inducedDistortion of utricle or saccule membranesSudden loss of postural tone from malfunction of vestibulospinal reflexUsually seen with Meniere’s diseaseOtolithic organs are central to gravity dependent tonic postural vestibulospinal reflexes.
43HENNEBERT’S SYMPTOM AND SIGN TULIO PHENOMENONOtolithic Tulio Phenomenon = sound-induced paroxysms of OTR (ocular tilt reaction) with cyclorotary nystagmus, oscillopsia and, hence, vertigo.HENNEBERT’S SYMPTOM AND SIGNPressure induced disequilibrium and vertigo (symptom)Pressure induced nystagmus (sign)Both are usually seen with perilymph fistula. Sometimes with Meniere’s disease, mastoiditis, labyrinthine trauma, congenital anomaly
44SUPERIOR SEMI-CIRCULAR CANAL DEHISCENNCE SYNDROME Un-roofing of the bony labyrinth over the Superior Semi-Circular CanalRelatively “new”Strange ComplaintsOften “falling” sensationTriggered by SoundPressure SensitiveHas diminished VEMPSurgical “Cure”Cause: Presumably Traumatic
45CERVICOGENIC DIZZINESS Existence is controversialNo clear anatomic pathwayAssociated neck pain , usually after whiplash or other injuryCervical-ocular reflex (normally minimal),may be exaggerated after neck injuryAssociated neck spasms and vaguesense of disequilibrium or dizzinessCause: Unclear. Existence: Controversial.
46VESTIBULAR OTOTOXINS Bilateral Vestibular Ototoxicity Aminoglycoside antibioticsLoop diuretics (Lasix)Cancer ChemotherapeuticsAspirinErythromycinVariable selectivityUsually hearing loss as well
48VESTIBULAR MIGRAINE Often no headache Non-positional Continuous hours to daysGradual on-set / off-set“Drifting” “Floating”“Utterly Indescribable”NauseaOptokinetic SensitivityMotion sickness historyDescending Nucleus Caudalis of CN V
49VESTIBULAR PAROXYSMIA Neuro-vascular Cross- CompressionRoot-entry zone irritationQuasi-positionalMixture of central and peripheralTrial of Carbamazepine or the likeSurgical “Cure”Seen in large number ofasymptomatic people
50CEREBELLAR PONTINE ANGLE (CPA) TUMOR Usually hearing loss and tinnitusVertigo or DisequilibriumOccasional facial paresis or spasmMixed Central / Peripheral SignsRoot-Entry Zone SignsVestibular SchwannomaMeningiomaBruns’ nystagmus =Gaze-evoked nystagmusSpontaneous nystagmus
51Mal debarquement Syndrome Central over-compensationPersistent “sea legs” on landPathophysiology unclearOften middle aged women
55STRUCTURAL LESIONS OFBRAINSTEM & CEREBELLUMDown Beat NystagmusLocalizes to Mollaret’sUsually lower in the regionUp Beat NystagmusLess localizingUsually higher in the region
56Alexander’s Law VERTICAL NYSTAGMUS Important distinction : “Up-Beat Nystagmus” is not “Upward Beating” Nystagmus“Up-Beat” Nystagmus“Down-Beat” Nystagmus“Upward beating”“Downward beating”Gaze evoked upward beatingUp BeatEccentric Position (gaze- evoked)Primary PositionAlexander’s Law
58GENETIC DISORDERS and VERTIGO Episodic Ataxia Type IAtaxia & MyokymiaPotassium Channel mutationAutosomal dominant, Chr. 12pEpisodic ataxia (minutes)Kinesiogenic choreoathetosisNo Vertigo, No NystagmusCerebellar dysfunction stableYoung childrenEpisodic Ataxia Type IIVertigo & NystagmusCalcium Channel mutationAutosomal dominant, Chr. 19pEpisodic ataxia & vertigo (hours to days)Progressive ataxiaAdolescents to adultsOther genetic Autosomal Dominant conditions:Familial episodic vertigo (without ataxia)Familial progressive bilateral vestibular failureFamilial periodic ataxia and smooth pursuit failure
59Paroxysmal OTRRotation of the eyes to keep visual vertical aligned with vestibular (gravity) verticalSpells or repeated bouts of cyclorotary nystagmus may be perceived as vertigoPathological variantsAssociated Skew deviationIpsilateral hypotropiaIpsilateral head tilt
60SUPERIOR OBLIQUE MYOKYMIA Motor “tic” of SO muscleRepeated short boutsHigh velocity intorsionMonocularUnique to SO muscleCause unknownTriggered by activating the superior oblique muscleVery rapid15 HertzFine oscillation1-5 degreesCreates visual blurring or“Shimmer”Usually no vertigo because this is a monocular phenomenon
61SEE-SAW NYSTAGMUS Lesion near the optic chiasm -- often with bi-temporal hemianopiaSuprasellar massHead TraumaThird Ventricle massThird Ventricle hemorrhageSEE-SAW NYSTAGMUSCyclorotary nystagmusConjugate rotationIntorting eye risesExtorting eye fallsLess likely --Rostral Mid- Brain Lesion (No field Cut)Congenital
62STRANGE BUT TELLING SYMPTOMS Lateropulsion -- feeling “forced” in one direction.Usually cerebellar or vestibular nucleus lesion.Room tilt illusion -- Feeling the world is tilted.Results from mismatch of visual and vestibular coordinates.Brainstem or cortex.Room flip illusion – Feeling that the floor becomes the ceiling, and then suddenly is the floor again.Visual world Instantly “flips” 90 to 180 degreesUsually a cortical malfunction.Can occur with vestibular nuclear lesion
63EVALUATION OF VERTIGO & DIZZINESS The evaluation begins with and depends upon the eye witness accountsThe accounts do no good …...if you do not listen to them
64“Listen. Listen. Listen to the Patient “Listen! Listen! Listen to the Patient. … He is telling you the diagnosis!”--- Rene Theophile Hyacinthe Laennec, 1774
65We think that we are better. We have technology. Technology is a poor substitute for thought.
66The key to success . . . Clear description Attentive listening Careful examinationClear thoughtThere is no easy way !
67TREATMENT OF VERTIGO Repositioning Maneuvers Drugs Surgery Physical TherapyExercisesUsually the ready application of the “Tincture of Time”