Pitfalls in Vertigo

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					                                                                                             The traditional approach to
             Pitfalls in Vertigo                                                             diagnosing the dizzy patient:
             High Risk Emergency Medicine                                                                  40%           30%                  10%               20%
            San Francisco                                          May 2009
                                                                                             What do you mean “dizzy”?

                            Jonathan A. Edlow, MD                                            Tell me how you feel without using the
                         Department of Emergency Medicine                                    word “dizzy”
                                                                                            More satisfying for the doctor
                        Beth Israel Deaconess Medical Center                                  Diagnostic testing will be more focused
                               Harvard Medical School                                         Less likely to make a diagnostic error or prescribe harmful treatment
                                     Boston MA                                                More likely to actually help the patient feel better




                Problems with the Traditional                                                                   Goals of the History
                         Approach                                                                 Symptom type. . .                 or. . .       Symptom timing?
•   Origin of the four categories
            Is from mono-symptomatic dizzy patients from ENT and neurologist-run referral
        •
            clinics seen days to weeks later                                                  •   What do you mean                            •       When did it start?
        •   ED dizzy patients are often poly-symptomatic (HA, CP, fever, etc) and present
            early                                                                                 dizzy?                                      •       How long did it last?
•   They do not account for real-world ED patient use of language
                                                                                              •   Tell me how you feel                        •       What triggers it?
        •   Sensory symptoms hard to describe                                                     without using the                           •       Is it episodic or
            Patients often change responses to type of dizziness
        •
                                                                                                  word ‘dizzy’.                                       persistent?
•   They under-represent important ED diagnoses that never get referred for
    “dizziness”                                                                                                                               •       If episodic, how many
        •   Systemic infections and febrile illnesses                                                                                                 episodes and how long
            Medication side-effects
        •
        •   Acute blood loss and other hypovolemic states
                                                                                                                                                      does each one last?
        •   Cardiac arrhythmias and heart failure
        •   Cerebellar and brainstem stroke




                          History - precision                                                         History                            Physical Exam
    •       Patients (and sometimes health care workers) often use                            •   Temporal patterns:
            the word ‘vertigo’ to incorrectly describe all kinds                                                                                  •   Vital signs – fever, "
                                                                                                  •   Onset, duration, constancy,
            of dizziness.                                                                             context                                         BP, ! pulse
                                                                                              •   Associated symptoms                             •   ENT
    •       Even if they use the word, “vertigo”, make them                                                                                               •   TMs
            describe their symptom without using the word                                     •   Past history                                            •   Weber and Rinné
            ‘vertigo’                                                                                  •   Migraine
                                                                                                                                                          •   Hearing
                                                                                                       •   Head trauma
                                                                                                       •   Vascular risk factors –                •   Neurological
    •       Research shows patients change category                                                        smoking, ! BP, diabetes                        •   Nystagmus
            frequently                                                                                                                                    •   Gait
                                                                                                                                                          •   Cranial nerves
       Vertigo & the Sense of Balance
•   Important survival benefit of
    knowing where we are in space
        •   Gravity (linear acceleration) sensed
            by utricle & saccule
        •   Angular acceleration sensed by
            semicircular canals
•   Gravity sensation is a tonic firing
    to the central connections
•   Angular (rotational) acceleration
    is transmitted to central
    connections by brief bursts of
    neuronal activity




                                                                                                Vertigo – history
                                                                                               2 simultaneous processes
                                                   Otoliths   Hair cells
                                                                           •   Distinguish between 3        •   Distinguish between 2
                                                                               temporal patterns                pathophysiologic and
                                                                               •   Acute spontaneous            anatomic sub-types
                                                                                   vertigo that slowly          •   Peripheral
                                                                                   improves over days           •   Central
                                                                               •   Episodic attacks of
                                                                                   spontaneous vertigo

                                                                               •   Episodic attacks of
                                                                                   positional vertigo
            Vertigo – Temporal pattern 1                                Pattern 1
    •    Acute spontaneous     Usually lasting days
         vertigo that slowly
         improves over days    Vestibular neuritis
    •    Episodic attacks of
         spontaneous vertigo    Cerebellar stroke
                                Brainstem stroke
    •    Episodic attacks of   Multiple sclerosis
         positional vertigo    Bacterial otomastoiditis
                               Labyrinthine concussion or infarct
                               Syphilitic or autoimmune labyrinthitis




            Vertigo – Temporal pattern 2                                Pattern 2
•       Acute spontaneous      Usually lasting minutes -
        vertigo that slowly    hours
        improves over days
                               Migraine (variable duration)

•       Episodic attacks of    TIA (VBI)

        spontaneous vertigo    Meniére’s

                               Rare
•       Episodic attacks of        Seizure
        positional vertigo         Perilymphatic fistula




            Vertigo – Temporal pattern 3                                Pattern 3
    •    Acute spontaneous       Usually lasts 20-30
         vertigo that slowly       seconds
         improves over days
                                 BPPV
    •    Episodic attacks of
         spontaneous vertigo     Rare
                                     Cerebellar mass
                                     Cerebellar atrophy
    •    Episodic attacks of
         positional vertigo
Pattern
                                                             Prolonged,                Vertigo – Temporal pattern 1
              1                                              non- episodic

                                                                              •   Acute spontaneous                Usually lasting days
                                                                                  vertigo that slowly
                                                                                  improves over days               Vestibular neuritis
              2                                              Spontaneous
                                                             episodes         •   Episodic attacks of
                                                                                  spontaneous vertigo               Cerebellar stroke
                                                                                                                    Brainstem stroke
                                                                              •   Episodic attacks of              Multiple sclerosis
                                                                                  positional vertigo               Bacterial otomastoiditis
                                                             Positional
                                                                                                                   Labyrinthine concussion or infarct
              3                                              episodes
                                                                                                                   Syphilitic or autoimmune labyrinthitis




                  Peripheral or Central?                                                   Peripheral or Central?
•    Small cerebellar or brainstem strokes can                                    •   Concomitant symptoms
     mimic peripheral vestibular processes
                                                                                  •   General features
•    Distinction is important
      •    Cerebellar infarctions may lead to swelling with                       •   Spontaneous nystagmus
           brainstem compression and death
      •    Underlying stroke mechanism goes untreated




                  Concomitant symptoms                                                         General Features
          Peripheral                   Central
                                                                                                        Peripheral                    Central
•    Hearing & ear                 •   Brainstem
     problems                          •   diplopia, dysarthria,             Imbalance                  Mild-moderate                 Severe
      •    deafness                        ataxia, long tract
      •    tinnitus                        symptoms                                                     (Walks but with difficulty) (Cannot walk)
           ear pain or fullness    •   Cerebellum                            Auditory Symptoms                                        Rare
      •

      •    mastoid discomfort          •   ataxia                                                       Common
                                           severe headache                   Neurological               Rare                          Common
                                       •

                                       •   nausea and vomiting*              Symptoms

    *: nausea and vomiting are also prominent with peripheral causes
                Spontaneous nystagmus                                            Head Impulse Test
                                                                             positive in vestibular neuritis
                       Peripheral         Central                            negative in cerebellar stroke
Appearance             Torsional and/or   Any direction, can
                       horizontal
                                          be pure vertical
Gaze                   Unidirectional     May change
                                          direction
Head impulse           Usually positive   Negative
test




            Direction-changing nystagmus                                         Vertical nystagmus
               (positive with central causes)                                (positive with central causes)




         Do not miss cerebellar stroke!                                             Neuro-imaging
•   Cerebellar stroke can be                                   •   What are you looking for? How emergent is it?
    confused with peripheral                                          •   Acoustic schwannoma (CP angle tumors)
    vestibular processes                                              •   Multiple sclerosis
                                                                      •   VBI
                                                                      •   Cerebellar infarct or hemorrhage
•   26/250 patients in a recent                                       •   Fourth ventricle tumors
    study had only peripheral
    symptoms                                                   •   How to best find it? (CT or MR)
    (Lee; Neurol; 67:1178; 2006)                               •   When: sudden onset vertigo and
                                                                      •   Stroke risk factors
•   Image patients suspicious                                         •   Associated severe HA or worrisome types of nystagmus
    for cerebellar stroke                                             •   Inability to walk
                                                                      •   Other CNS signs on exam
            Cerebellar Hemorrhage                                            Cerebellar Infarction




        Vertigo – Temporal pattern 2                                                      Pattern 2
•   Acute spontaneous           Usually lasting minutes -
    vertigo that slowly         hours
    improves over days
                                 Migraine (variable duration)

•   Episodic attacks of          TIA (VBI)

    spontaneous vertigo         Meniére’s

                                Rare
•   Episodic attacks of             Seizure
    positional vertigo              Perilymphatic fistula




                                                                            Dizziness and the TIA
          Migraine                         Vertigo              •   Conventional wisdom: Isolated dizziness is rarely caused by a
                                                                    TIA
          headache
                                                                •   When dizziness (usually vertigo) is from a TIA
                                                                    •   other brainstem symptoms are almost always present
                                                                    •   duration usually minutes


                                                                •   Kerber (Stroke; 27: 2484; 2006) showed 53/1666 (3.2%) of adult
                                                                    patients with “dizzy, vertigo, imbalance” patients had TIA or
                                                                    stroke (however for “isolated” dizzy symptoms 0.7%)
                          Motion                                •   Norrving: 25% of 24 elderly patients with episodic vertigo
                                                                    had VBI
                          sickness
                                                                •   Lee study showed 10% of cerebellar infarctions presented
                                                                    like a peripheral vestibular process
        Treatment of Peripheral Vertigo                                    Drugs (labyrinthine suppressants)
    •   Drugs                                                      •   Anticholinergics that cross the BBB
                                                                       •   Antihistamines
         •   Steroids for vestibular neuritis                                  •   1 small study (31 pts) showing meclizine > placebo
              •   Prednisone (Strupp; NEJM 2004)                       •   Phenothiazines (phenergan)
              •   141 patients: steroids/valcyclovir/both              •   Benzodiazapines – short acting (lorazepam)
                                                                       •   Scopolamine patch
         •   Labyrinthine suppressants
    •   Position exercises                                         •   Short term only (few days)

                                                                   •   It’s important to understand which syndrome
                                                                       you’re treating and factor in side-effects




         Vertigo – Temporal pattern 3                                                          Pattern 3
•   Acute spontaneous                     Usually lasts 20-30
    vertigo that slowly                     seconds
    improves over days
                                          BPPV
•   Episodic attacks of
    spontaneous vertigo                   Rare
                                              Cerebellar mass
                                              Cerebellar atrophy
•   Episodic attacks of
    positional vertigo




        Diagnostic maneuver - Dix-Hallpike                             Dix-Hallpike . . or Head thrust?
                    (or Barany)
Therapeutic maneuver - Epley




                                                   FAQ about the Epley
                               •   Which side do I start with?    •   The one with + Dix-Hallpike
                               •   How many repetitions?          •   Till D-H is negative (~ 2-4 x)
                               •   Post-Epley restrictions?       •   Not needed
                               •   How often is it successful?    •   ~ 85% of time
                               •   Why should I bother?           •   Natural history weeks-months
                               •   Are there contraindications?   •   Carotid stenosis, C-spine
                                                                      disease, active cerebral or
                                                                      cardiac ischemia
                               •   Pre-treat with anti-emetics?   •   Not required; some do
                Dizziness - disposition       Clinical bottom line
•   Most do not have serious              •   Algorithmic approach
    illness and do not need
    imaging                               •   Understand and exploit
•   Use history and exam to                   the triggers and timing for
    identify those who do
                                              patients with vertigo
    •   Vascular risk factors & age
    •   Severe headache
    •   Inability to walk                 •   Try to make a specific
    •   Quality of nystagmus                  diagnosis
    •   Other CNS findings (except "
        hearing)                          •   Know which diagnostic
•   Image those select patients,              tests and treatments work
    preferably with MR                        for each of them
•   Ensure environmental safety

				
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posted:9/16/2011
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