2Balance and Equilibrium The ability to maintain orientation of the body and its parts in relation to external space.Interaction between self and environment.Sensory input from visual, vestibular, and proprioceptive information.Integration in the brain stem and cerebellum.
3Disorders of Equilibrium Diseases affectCentral or peripheral vestibular pathwaysCerebellumProprioceptive sensationMismatch of input signals and disintegrationSymptomsVertigoAtaxia
4Vertigo and Dizziness Vertigo 眩暈 Dizziness 頭昏 Illusion of movement of the body or the environment.Impulsion, oscillopsia, nausea, vomiting, cold sweating, or unsteadinessDizziness 頭昏No association of illusion of movementLight-headedness, faintness, giddiness, swimming
5Vestibular System Semicircular canal Otolith organs Sense angular accelerationHead rotationOtolith organsSense linear accelerationHead translation and uprightness
23Cerebellar System Archicerebellum The oldest cerebellum Flocculonodular lobevestibulocerebellumPaleocerebellumAnterior lobeSpinocerebellumNeocerebellumPosterior lobePontocerebellumThe oldest cerebellumCaudal partEye/head movementThe next oldestMidlineNeck/trunk movementThe newest cerebellumHemsiphereLimb movement
29The Saccades, Pursuit, and Vestibular Control of Eye Movements
30Dizziness History Near-faint Disequilibrium without vertigo Vertigo Psychological dizzinessPhysiological dizzinessCentral originPeripheral origin
31Distinguishing Vestibular From Nonvestibular Dizziness DescriptionSpinning, falling, drunkenness, motion sickness, tiltingFloating, near-fainting, fatigue, head fullness, out-of body sensationPrecipitating factorsHead movements, position changesStanding after sitting or lying, cardiac disease, agoraphobiaAssociated featuresNausea, vomiting, unilateral tinnitus or hearing loss, imbalance, oscillopsiaPalpitation, diaphoresis, syncope, loss of concentration, dyspnea
32Physiological Vertigo TypeProvocative stimulusMechanismMotion sicknessProlonged passive head movement or movement of the environmentVestibular-visual conflictVisual vertigoExcessive visual stimulationMal de debarquementLong voyage on ship or planeMaladaptation to chronic vestibular stimulationHeight vertigoStanding in a high place looking outLack of nearby stationary objects in peripheral visionSpace sicknessZero gravityCanal-otolith conflict
36Disorders of the Semicircular Canal Disorders of the Otolith OrgansVertigo (spinning of the environment or the self)NystagmusPast-pointing of the limbsAtaxiaPositive Romberg signTurning during steppage testTilt, a false sense of linear motionVertical diplopiaSkew deviationAtaxiaPositive Romberg signTranslation on the steppage test
38Differentiating Peripheral From Central Vertigo Nausea/vomitingSevereVariable, mildImbalanceMild-moderateHearing lossCommonRareNeurological symptomsNystagmusUnidirectional in all gaze; inhibit with fixationDirection-changing in different gaze; not inhibited with fixationCompensationRapidSlow
41Causes of Dysequilibrium without Vertigo Disorders of afferent sensesBilateral vestibular lossSensory ataxiaMultisensory disequilibriumDisorders of central processing and motor responsesCerebellar degenerationFrontal lobe syndromeExtrapyramidal syndrome
43Approach to Vertigo and Dizziness General examinationBP in the lying and standingLook for cardiac arrhythmiaExamination of extracranial and peripheral vasculature
44Approach to Vertigo and Dizziness Neurological examination (1)Consciousness and mental statusVisual acuity and visual fieldFundusScreening for hearing impairmentOcular motor examinationNystagmusOcular motor palsySlow or ataxic ocular movement
45assessing current history Ask the patient to describe the symptoms without using the word dizzy. Have the patient differentiate vertigo from presyncope or near-syncope.Determine if the patient has a sense of being pushed down or pushed to one side (pulsion). A peculiar sense of movement of objects viewed when the patient moves is termed oscillopsia.Ascertain whether the symptoms are related to an anxiety attack; patients with agoraphobia may describe their symptoms as dizziness.Determine if the sensation is continuous or episodic (ie, attacks); if episodic, find out if the sensation is fleeting or prolonged.Ascertain whether the onset and progression of symptoms were slow and insidious or acute.
46Ask the patient about head trauma and other illnesses to determine the setting of the initial symptoms. Trauma resulting in damage to an ear often manifests as unilateral hearing loss, which may be the cause of episodic vertigo even years later (posttraumatic hydrops).Determine if the attacks are associated with turning the head, lying supine, or sitting upright.Determine if symptoms of an upper respiratory infection or flu-like illness preceded the onset of vertigo.Inquire about associated symptoms such as hearing loss or tinnitus (ringing in the ears), aural fullness, diaphoresis, nausea, or emesis.Determine if the patient has an aura or warning before the symptoms start.If hearing loss is evident, find out if hearing fluctuates.Determine if the patient has a headache or visual symptoms such as scintillating scotoma.Ask the patient about brainstem symptoms such as diplopia, dysarthria, facial paresthesia, or extremity numbness or weakness.Ascertain the degree of impairment during an attack
47Examination of Vestibulo-ocular Reflexes Spontaneous nystagmusElicit slow phases with slow head rotation, in yaw (horizontal), pitch (vertical), and roll (torsion), and with high accelerations in yaw and pitch (head thrust)Caloric testHead-shaking nystagmus
50Vestibulospinal Testing Past-pointing with arms, with eyes closedRomberg: feet apposed, in tandem, in tandem on toes, on one foot at a time, standing on compliant foam rubberFukuda stepping test or walking around a circleTandem gait, forward and backward
52Approach to Vertigo and Dizziness Neurological examination (2)Motor system examinationFocal or diffuse weaknessReflex changesSensory examinationStock-and-gloving sensation loss: polyneuropathyLoss of vibratory and proprioceptive sensation: Vit B12 deficiency or tabes dorsalisRomberg’s sign
53Approach to Vertigo and Dizziness Neurological examination (3)Cerebellar examinationObservation of sitting and standing and walkingBending backwardTandem gaitWalking around a chairFinger-nose-fingerHeel-knee-shin
54Approach to Vertigo and Dizziness Neurological examination (3)Cerebellar examinationPronation-supinationKnee-pattingRapid touching of each finger to the thumbArm deviationArm tappingRebound test
56Benign paroxysmal positioning vertigo Phobic postural vertigo The Most Common Causes of Vertigo Syndromes Seen in a Neurological ClinicBenign paroxysmal positioning vertigoPhobic postural vertigoBasilar migraineMeninere’s diseaseVestibular neuritis(T. Brandt, “Vertigo, its multisensory syndrome”)
63Benign Paroxysmal Positional Vertigo (BPPV) – Symptoms & Signs Brief attacks of rotational vertigo and concomitant rotatory nystagmus precipitated by rapid head tilt, turning or extension.The symptoms can be induced by Hallpike maneuver.Typical peripheral vestibular nystagmus, short latency, limited duration, reversal on returning to the upright position, and fatigability on repeated provocation.
64Benign Paroxysmal Positional Vertigo (BPPV) – Pathogenesis & Treatment Otolith debris floats freely within the endolymph of the semicircular canal: canalolithiasis.Heavy debris settles on the cupula transforming it as a transducer of angular acceleration into a transducer of linear acceleration: cupulolithiasis.Treatment by canal repositioning or libratory maneuvers.
69Meniere’s Syndrome – Symptoms & Signs Fluctuating hearing loss, tinnitus, episodic vertigo and a sensation of fullness or pressure in the ear.Attacks lasted for hours but dizziness and unsteadiness remain for a few days.Repeated attacks lead to progressive tinnitus, hearing loss, and impaired vestibular function.Usual in the fourth to sixth decades.
70Meniere’s Syndrome – Pathogenesis & Treatment Endolymphatic hydrops: increase of volume of endolymph associated with distension of entire endolymph system.The attacks are caused by rupture of membranous labyrinth leading to paralysis of the surrounding vestibular or cochlear hair cells and neural structures.Symptomatic treatment of acute spells.Salt restriction and diuretics.Intratympnic treatment with ototoxic antibiotics.Labyrinthectomy or vestibular neurectomy.
72Basilar Migraine – Symptoms & Signs Vertigo may occur in about one-fourth of migraine patients, and can occur without headache.Other symptoms of basilar migraine include ataxia, dysarthria, diplopia, visual symptoms, tinnitus, decreased hearing, bilateral pareses or paresthesia and decreased level of consciousness.Benign paroxysmal vertigo of childhood.Benign recurrent vertigo of adulthood.Motion sensitivity with frequent bouts of motion sickness occurs in at least one-half of patients with migraine.
73Basilar Migraine – Pathogenesis & Treatment Vasoconstriction (?). Neuronal depression (?).Genetic.Channelopathy.Symptomatic treatment of acute attackAntivertiginous medications.Antiemetics.Sumatriptans and ergotamines often are ineffective and even aggravate vertigo.Prophylactic treatment of attacksBeta-blockers.Calcium channel blockers.Valproic acid.Tricyclics.
75Vestibular Neuritis – Symptoms & Signs Vertigo, nausea, and vomiting developed over several hours, reach a peak within 24 h, and resolve gradually over several weeks.Generally without hearing symptoms.Diagnosis is based on acute unilateral peripheral vestibular loss and exclusion of other inner ear diseases.Ramsay Hunt syndrome by varicella-zoster infection may causes facial paresis, tinnitus, hearing loss, and a vestibular defect.
76Vestibular Neuritis – Pathogenesis & Treatment Presumed of viral origin.Similar to Bell’s palsy caused by reactivation of dormant herpes infection in the Scarpa’s ganglion within the vestibular nerve.Treatment is symptomatic. Antivertiginous medication should not be given as long as nausea and vomiting subsides. These drugs suppress central compensation.Corticosteroid may shorten the clinical course.Vestibular rehabilitation exercise.
78Drugs That Can Cause Dizziness or Be Harmful to the Dizzy Patient Drugs that causes dizzinessDrug that interfere with vestibular compensationOtotoxicAnti-arrythmicsamiodarone, quinine+Anticonvulsantsbarbiturates, CBZ, PHTAntidpressantamitiptyline, imipramineAntihypertensivesDiureticshydrochlorothiazide, furosemidAntiinflammatory Drugsibuprofen, indomethacin, ASAAntibioticsaminoglycosidesChemotherapeuticscisplatinHypnoticsMuscle relaxantsTranquilizersBZDVestibular suppressantsmeclizine, scapolamine