Approach to the Patient with Dizziness

Transcription

1 Approach to the Patient with Dizziness Ricardo Cristobal, M.D., Ph.D., F.A.C.S. Otology, Neurotology and Skull Base Surgery Texas Ear Clinic Fort Worth, TX

2 Definitions Vertigo: Illusion of movement of the entire surrounding (objective) or self (subjective). Specific to vestibular system. Dizziness: general term, can encompass imbalance, lightheadedness, subjective (environment) or objective (self) vertigo or a combination of the two Oscillopsia: Optical illusion that entire visual environment oscillates c head movements

3 Balance

4 Balance System Function EQUILIBRIUM: Rapidly correct any inadvertent displacement of center of mass to prevent a fall ORIENTATION: Provide accurate perception of head and body position in the environment VISION STABILITY: Control eye movements to maintain clear visual image of the external world, while the environment, individual or both are moving.

5 Vestibular System Peripheral vestibular system: Inner ear labyrinth Vestibular nerve Central vestibular system: Vestibular nuclei Neuronal connections

6 Vestibular Anatomy

7 Vestibular Nuclei Projections

8 Vestibular System Function: Eye Movement Control Image stabilization in retina Out of focus for >3-5 deg/sec Vestibular system operates during: Rotational and translational head movements (SCCs through VOR; maculae through otolithic reflexes) Main mechanism during natural head movements (0.5-5 Hz). Fast processing (<16 msec SSCs, <35 msecs maculae), 3 neuron arch

9 Vestibular System Function: Eye Movement Control Other non-vestibular sources: Optokinetic system: slow moving objects (<0.1 Hz). Sluggish (processing >75 msec) Saccadic system: brings object from peripheral retina to fovea Smooth pursuit system: stabilizes smoothly moving foveal targets in retina Overlap of mechanisms: tracking w head movements

10 Approach to Dizzy Patients Dizziness not always vestibular problem History determines examination and diagnostic workup Describe sensation, how it starts, duration, frequency, precipitating factors, associated symptoms, predisposing factors

11 Kroenke, 2000

12 Approach to Dizzy Patients Type Mechanism Eval Vertigo Near-faint Dizziness Psychophysiological Dizziness Hypoglycemic Dizziness Disequilibrium Imbalance in tonic vestibular signals, central pathways Decreased blood flow to entire brain Impaired central integration of sensory signals Inadequate brain glucose, increased catecholamines Loss of sensorimotor control Auditory and vestibular system Cardiovascular system Psychiatric assessment Metabolic assessment Peripheral nerves, spinal cord, inner ear, CNS

13 History of Vertigo Vertigo: Illusion of movement. Vestibular specific. Absence does not rule out vestibular disease. Most commonly due to asymmetry of baseline tonic firing of vestibular afferent nerves. Most frequently rotational: usually horizontal/torsional nystagmus Input from opposite vestibular organs greater, vertical canals partially cancel out. Otolithic reflexes only require one side

14 History of Vertigo Horizontal nystagmus: Vision blurred, objects move opposite to slow component (away from side of lesion). There are no eye proprioceptive receptors, brain interprets as visual field movement. When eyes closed feels like body moves towards side of lesion

15 History of Vertigo Other types of vertigo sensation: linear displacement, tilt Vertigo becomes worse with rapid head movements (vestibular imbalance): turning in bed, sitting up, neck extension, bending over Autonomic dysfunction almost always present (sweating, pallor, N & V)

16 History of Vertigo Slow bilateral loss: oscillopsia with head movements, instability Slow unilateral loss months to yrs: asymptomatic Sudden unilateral: severe vertigo, N & V, diaphoresis, pale: able to walk but fall to same side, may interfere with vision, lie quietly in the dark Course: young patients can walk w/in 1 week, inhibit nystagmus c fixation; 1 month no residual sx

17 History of Vertigo Coughing, sneezing: fistula, SSCC dehiscence Tulio phenomenon: SSCC dehiscence, Meniere s (adhesions) Duration: Seconds: BPPV, cervical disk problems Minutes: vascular (migraine, vertebrobasilar insufficiency) 3-4 hours: Meniere s disease (dizzy <24 hr p episode) Several days, acute onset: Viral labyrinthitis

18 History of Vertigo: Associated Symptoms Labyrinth, CN VIII: auditory sx (HL, tinnitus, pressure, pain). IAC: facial sx CPA: facial numbness, weakness, ipsilateral extremity ataxia, lower CN weakness Brain stem: no HL Transient vertebrobasilar insufficiency: diplopia, hemianopsia, drop attacks, weakness, numbness, dysarthria, ataxia Cerebellum: truncal and extremity ataxia Temporal lobe seizure aura: w or w/o taste, smell hallucinations

19 History: Oscillopsia Oscillopsia: Optical illusion that entire visual environment oscillates c head movements Acute unilateral peripheral loss: unable to fixate, objects blurry and moving. If poor compensation: persistent head movement-dependent oscillopsia Bilateral symmetrical vestibular loss: oscillopsia with any head movement. Unable to fixate with walking, reading difficulties. Cerebellar lesions: oscillopsia and spontaneous nystagmus with stationary head or with head movements (unable to suppress VOR with fixation) Lesions of central vestibulo-ocular pathways: constant oscillopsia, associated w neurological symptoms

20 Most Common Dizziness of Vestibular Origin <24 Hours >24 Hours Hearing Loss Meniere s Disease Labyrinthitis No Hearing Loss BPPV Vestibular Neuritis Vestibular Migraine

21 Meniere s Disease Transient, reversible Membrane rupture with mix of endolymph and perilymph Symptoms: Episodic Aural fullness Roaring tinnitus Fluctuating hearing loss Vertigo followed by dizziness, <24 hrs Associated nausea, vomiting Feel well the next day Gradual hearing loss Signs: Nystagmus during or soon after episode

22 Meniere s Disease Testing: Low frequency sensorineural hearing loss Positive Electrocochleography Caloric weakness Weak Vestibular Evoked Myogenic Potentials Treatment: Low salt diet HCTZ and triamterene Acute: antiemetic, vestibular supressant Vestibular therapy not helpful Others: gentamycin injection, labyrinthectomy, vestibular nerve section

23 BPPV Benign Paroxysmal Positional Vertigo Most common 5 th to 7 th decade Unclear cause: idiopathic 50-70%. Vestibular migraine, others Origin: Posterior canal 60-65%, horizontal canal 30-35%, anterior canal 1-3%. (Chung KW et al, 2009) Honrubia et al., Neurology

24 BPPV Symptoms: vertigo, nausea with rolling in bed, looking up or down, quick head turning Test: Dix-Halpike: Delay Fatigue Upbeating extorsional nystagmus Reverses Treatment: Dix Hallpike Modified Semont Brandt Daroff Singular neurectomy Canal plugging Baloh et al. Clnicial Neurophysiology of the vestibular system. 2011

25 Vestibular Neuritis Cause: nerve inflammation, superior > inferior Symptoms: Abrupt onset of vertigo, nausea, vomiting for hours to 1 day, +/- prodrome of dizziness Worse with head movement? Prior history of URI NO auditory or central nervous system signs and symptoms Dysequilibrium while ambulating up to 3 months Some patients repeated episodes of vertigo Association with BPPV

26 Vestibular Neuritis Signs: Rotary nystagmus in opposite direction Diagnosis: Caloric testing: vestibular nerve weakness Rotational testing: degree of compensation MRI: nerve enhancement Treatment: Acute: antiemetics, hydration, vestibular supressants, steroids, NO evidence evidence for antivirals Chronic: Vestibular rehabilitation therapy, treat BPPV AVOID VESTIBULAR SUPRESSANT MEDICATIONS

27 Labyrinthitis Infection in perilymphatic space: serous or toxic: milder, more common Insidious progressive high frequency hearing loss suppurative: rare Fulminant. Sudden onset of vertigo, nausea, vomiting and unitlateral or bilateral hearing loss Treatment: antibiotics

28 Vestibular Migraine Hallmark: sever attacks of headaches Other features: dizziness, visual phenomenon, hypersensitivity to sensory stimuli, nausea, paresthesias, rarely focal weakness Dizziness: sensitivity to motion, disorientation, difficulty focusing on a task, true spinning sensation The great mimicker: may resemble Meniere s syndrome, BPPV and vestibular neuritis

29 Vestibular Migraine 25% of migraine patients have episodic vertigo 25% of patients w vestibular migraine have headaches More common during headache-free periods Symptoms: Attacks minutes to days Vertigo spontaneous or positional (also BPPV more common) Phonophobia 2/3 of patients, usually w headache Low frequency fluctuating HL in women during menses (Meniere s disease HL is progressive) Higher incidence of sudden HL

30 Vestibular Migraine Diagnosis: NO diagnostic criteria from IHS Suggested criteria: 1. Recurrent vertigo attacks 2. Migraine that meets IHS criteria 3. Migranous symptoms during at least 2 attacks (HA photophobia, phonophobia, aura symptoms) 4. Vertigo that cannot be attributed to another disorder If not meet # 3: probable migranous vertigo Neuhauser and Lempert. Neurol. Clin 2009.

31 Vestibular Migraine Treatment: Symptomatic: antivertiginous and antiemetic medications (promethazine both) Prophylactic: Poorly studied for vertigo, general sentiment. Spontaneous remission Search for and reduce triggers, lifestyle measures Based on comorbidities: Obesity or seizures: topiramate Depression or anxiety: tricyclic amine or SSRI HTN: beta-blocker or verapamil

32 Summary Factor Vestibular Non-Vestibular Common description Spinning (environment), merry-go-round, drunkenness, tilting, motion sickness, off balance Course Episodic Constant Light-headed, floating, swimming, giddy, spinning inside (environment stationary) Common precipitating or aggravating factors Commonly associated symptoms Head movements, position change Nausea, vomiting, unsteadiness, tinnitus, HL, impaired vision, oscillopsia Stress, hyperventilation, cardiac arrhythmias, situations Paresthesias, syncope, difficulty concentrating, tension headache

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