DIZZINESS AND VERTIGO


See also "Syncope"

I. Types of dizziness

  1. Vertigo: an illusion of movement, us. rotation
  1. Arises from disturbances of vestibular system or neural structures afferent to this (CN VIII, cerebellum, brainstem nn, c-spine proprioceptive fibers)
  2. Causes include BPV, labyrinthitis, vertebrobasilar TIA/CVA, & Meniere's disease
  3. Accompanying nausea suggests peripheral rather than central etiology, as do ear symptoms
  1. Presyncope: a sensation one is about to lose consciousness, with lightheadedness and sometimes nausea or falling. n.b. syncope alone can give brief eye-rolling and myoclonus, like sz, from hypoxia
  1. Arises from cerebral hypoxemia, us. from ischemia
  2. Can be precipitated by vol. depletion, meds, EtOH, vagal surge, infection, orthostatic hypotension (e.g. from meds, autonomic insufficiency), arrhythmias
  3. Other causes include anemia, CO poisoning, pulmonary disease, MI, aortic stenosis, adrenal insufficiency, "subclavian steal"
  4. Represents global, not local, cerebral hypoxia, so not the same as TIA
  1. Dysequilibrium: a sense of imbalance, "a body sensation more than a head sensation"
  1. Results from disruption of the balance system, e.g. vestibulospinal, proprioceptive pathways, vestibular system, cerebellum, visual system, peripheral motor nn, muscles, cerebral cortex.
  2. Usually multifactoria, e.g. mixed motor & visual impairment
  1. Dizziness associated with psychiatric problems, e.g. anxiety. Often accompanied by symptoms of dissociation
  2. Multiple neurosensory impairments, involving cognitions, vision, proprioception, vestibule, cerebellum, motor weakness, etc.

II. Evaluation

  1. Very common in elderly, not associated with increased risk of death
  2. May frequently be due to more than one problem and can't always make dx immed.
  3. Px:
  1. Vital signs with orthostatics
  2. Fundoscopy
  3. Cranial nn. exam, with check for nystagmus & hearing
  4. Otoscopy with insufflation
  5. Tandem gait
  6. Romberg
  7. Carotid upstrokes
  8. C-spine ROM
  9. Forced hyperventilation if suspect panic disorder
  10. Hallpike-Dix Maneuver
  11. March in place for 30sec w//eyes shut and arms extended; if vestibular dysfunction exists, will rotate >30'

III. Clinical entities

  1. Acute labyrinthitis aka "vestibular neuritis" or "acute peripheral vestibulopathy"
  1. Destruction of 1 or more labyrinths from viral or vascular cause
  2. Occas. preceded by viral-like illness
  3. Rapid-onset vertigo with n/v, diaphoresis, & horizontal nystagmus
  4. May get hearing loss & tinnitus if auditory apparatus affected
  5. Young people generally spontaneously improve in 1-2d as their brains learn to substitute other sensory info for lost vestibular info
  6. Older pts may have vertigo or other dizziness sx for months-yrs b/c of decreased sensory balance reserve, theoretically
  7. Treatment
    1.  Meclizine or promethazine for symptomatic relief
    2. Low-dose benzodiazepines may relieve protracted sx
    3. Methylprednisolone x 3wks (starting at 100mg/d then tapering) was ass'd with sig. greater improvement in vestibular paresis as assessed by computer analysis of caloric irrigation at 1y c/w placebo in a randomized trial of 141 pts with acute labyrinthitis, though valacyclovir 100mg TID x 1wk, in the same trial (2 x 2 factorial design), was not (NEJM 351:354, 2004--JW)
  1. TIA's of vertebrobasilar system (ant. circ. dysfn shouldn't cause dizziness)
  1. Vertigo often w/ ataxia, dysarthria, diplopia, hemiplegia/hemianesthesia
  2. Occas. get HA; rarely get syncope
  3. <50% go on to have CVA
  4. Tx = control of risk factors & give ASA
  5. "Subclavian steal" sd. = a treatable form (surgically?)
  1. CVA of vertebrobasilar system: presents similarly to TIAs
    1. May comprise 5% of ED visits for dizziness
    2. Typical locations are lateral brainstem or inferior cerebellum
    3. MRI may not show evidence of vertebrobasilar CVA in the first 48h after onset of symptoms
    4. Physical findings as below may indicate presence of vertebrobasilar CVA in a patient with acute-onset vestibular symptoms, with much higher sensitivity than traditional neurologic signs such as limb ataxia, hemiparesis, or gaze palsy (paper presented by David E. Newman-Toker at American Neurologic Association meeting, FP News 12/09):
      1. Horizontal head impulse test (tests vestibulo-ocular reflex function)
        1. A rapid, passive head rotation from lateral (10-20' rotation) to central position as the patient fixates at a central target
        2. A normal response is an eye movement equal and opposite to the passive head movement so that the eyes stay stationary in space (i.e. still looking straight at the target).  In an abnormal response, the patient is unable to maintain fixation during the head rotation, requiring a corrective gaze shift once the head stops moving.
        3. A normal VOR by this test suggests a central localization of the source of vestibular symptoms
      2. Nystagmus that is vertical or torsional, or changes direction (in terms of the fast-slow phases) when the patient looks in the directon of the slow phase
      3. Test for skew deviation with alternating-cover test
        1. While patient fixates on a central target, examiner alternatively occludes each eye
        2. Cover is removed suddently
        3. Normal response is for eyes to remain motionless
        4. Abnormal response is a "refixation saccade", indicating either frank ocular misalignment (heterotropia) or a propensity for such misalingment when binocular cues are removed (heterophoria).
  2. Migraine: can give sx similar to vertebrobasilar TIA, in fact, hard to distinguish the two. Migrain more likely to show scotomata or other visual disturbances; migratory paresthesias; progression from one sx to another
  3. Benign positional vertigo
  1. Very common; caused by vestibular damage (e.g. from infection, trauma); otoliths loose in a semicircular canal; eventually are reabsorbed or scarred over
  2. Described by Hallpike and Dix as "positional nystagmus"in their landmark paper (Ann. Otol. Rhin. Laryngol. 6:987, 1952): "The giddiness comes on when [the pt] lies down in bed or when such a position is taken up during the day; for instance, in lying down beneath a car or in throwing the head backward to paint a ceiling...he may be able to cause his vertigo to disappear by maintaining his head in the disagreeable position, or by taking up this position slowly."
  3. Sx occur only during or after position changes; last only seconds to a minute
  4. Come in flurries of attacks for 1-2wks then months-yrs without sx; may or may not recur
  5. No other neurologic sx (except maybe nau/vom); no auditory sx; benign course
  6. Dx = Hallpike-Dix maneuver
  7. Tx
  1. Positional exercises x hrs at a time to fatigue response, e.g. "Epley" procedure
  2. Falling rapidly to one side or the other from a sitting position in bed
  3. Meds generally not helpful
  4. Backward but not forward rotation in a flight simulator ("canal-clearing" procedure) was effective at resolving sx in 2/3 of patients with BPV (Neurology 49:720, 1997 and BMJ 311:489, 1995-JW)
  5. A "canalith repositioning procedure" was sig. more likely than a sham procedure (50% vs. 19%) to result in resolution of BPV sx in a randomized trial of 50 pts with BPV (Mayo Clin. Proc. 75:695, 2000--JW)
  1. Central positional vertigo
  1. Arises in certain positions
  2. No latency or fatiguability on provocational testing like BPV
  3. Causes include tumor, posterior CVA, MS, vertebral artery impingement
  1. Meniere's disease
  1. Recurrent vestibulopathy: common but poorly understood
  1. Vertigo with n/v, nystagmus, in a recurrent pattern, e.g. Qyr
  2. Most resolve in a few yrs, some continue, some change to BPV, some to Meniere's
  3. Tx = meclizine
  1. Bilateral vestibular dysfunction, e.g. from aminoglycosides
  1. Get dysequilibrium, worse while standing
  2. Get feeling of oscillopsia (eyes bouncing up & down) when walking
  1. Cervical vertigo
  1. Vertigo or more vague lightheadedness, from irritation of proprioceptive c-spine fibers, e.g. from DJD or mm. spasm
  2. Often accompanied by occas. HA or neck stiffness/pain
  3. Tx = treat underlying problem
  1. Middle ear disease, e.g. serous otitis, cholesteatoma, cerumen against TM
  1. Can give vertigo or vague lightheadedness
  2. Often with sensation of ear stuffiness
  1. Neurosyphilis
  1. Usually bilat. hearing loss; vertigo a less prominent symptom
  1. Perilymphatic fistula
  1. Disruption in round window, so that perilymph goes into middle ear; usually resulting from trauma, e.g. head bonk or noise
  2. Get persistent dysequilibrium & vertigo precipitated by cough/straining
  3. Can sometimes precipitate vertigo with pneumatic otoscopy
  1. Acoustic neuroma
  1. Presents with unilateral hearing loss; occasionally with continuous lightheadedness or vertigo
  2. Dx = audiometry w/ speech discrimination; MRI
  1. Continuous (vs. episodic) dizziness
  1. Rare; usually from multiple neurosensory deficits vs. psych; the latter is suggested by sx of dissociation ("floating," etc.), or other somatic complaints
  2. Other causes include cerebellar atrophy, anemia, MI or other acute illness, or s/p posterior CVA (after acute vertigo is resolved)
  1. Ocular dizziness: symptomatology can be any form of dizziness
  1. Caused by change in corrective lens, fluctuation in glucose, or cataract surgery

IV. Treatment principles

  1. Antihistamines & sedatives can worsen the problem, but in low doses may help
  2. For BPV
    1. Maneuvers designed to reposition otoliths and/or "vestibular rehabilitation" have been shown effective (e.g. Mayo Clin. Proc. 75:695, 2000--AFP)
  3. Deconditioning can worsen things, so physical therapy may help
  4. Treat visual problems, e.g. cataracts, if possible
  5. A single session of "vestibular rehabilitation" with instructions to do specific exercises BID x 3mos (various head movements w/eyes open & closed) was ass'd with sig. higher incidence of clinically significant improvement in sx (67% vs. 38%) c/w "usual care" in a randomized trial in 170 adults with > 2mos of movement-provoked dizziness (mixed Meniere's, labyrinthitis, BPV, and unknown etiology) (Ann. Int. Med. 141:598, 2004--JW)