Dizziness

1
Dizziness

• Pete Kang
• NYU School of Medicine
• Class of 2001

2
Dizziness epidemiology

• 1.5 of all hospital admissions
• 26 of all ED pts stated that they had
  experienced dizziness
• Most common non-pain-related complaint in the ED
• Account for 8 million outpatient visits per year
  in the U.S.
• Adult gt Pediatric

3
Dizziness differential diagnosisbroad
categories of diseases

• Vertigo
• Near-faint or Presyncope dizziness
• Psychophysiologic dizziness
• Hypoglycemic dizziness
• Disequilibrium
• Drug-induced dizziness

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Vertigo subclasses

• Acute spontaneous attack
• Recurrent spontaneous attacks
• Recurrent episodes of positional vertigo

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Acute spontaneous attack of vertigo

• Unilateral loss of vestibular function
• Clinical presentation
• Intense sense of rotation aggravated by head
  motion
• World turns slowly toward intact side, then
  quickly toward affected side
• Prefers to sit upright w/ head still or to lie w/
  intact side undermost
• Difficulty in standing/walking may fall toward
  affected side
• May have nausea/vomiting, malaise, pallor,
  diarrhea

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Peripheral vs. Central lesions

• Peripheral
• Severe nausea/vomiting
• Mild imbalance
• Hearing loss common
• Mild oscillopsia
• No focal signs
• Rapid compensation

• Central
• Mod. nausea/vomiting
• Severe imbalance
• Hearing loss rare
• Severe oscillopsia
• Focal signs
• Slow compensation

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Viral neurolabyrinthitis

• Most common gt90 of cases in younger age group
  w/o major vascular risk factors
• Subacute onset URI 2 weeks prior
• Unilateral caloric paresis, /- hearing loss
• No other focal signs
• Symptomatic management, vestibular rehabilitation

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Bacterial otomastoiditis w/ labyrinth involvement

• Prior infection bony erosion seen in CT
• Possible cholesteatoma
• Possible complication of bacterial meningitis
• Antibiotics
• Surgical debridement

9
Cerebellar infarct/hemorrhage

• Elderly, w/ vascular risk factors
• Other focal neurological signs present usually

10
Multiple sclerosis

• Vertigo is the presenting symptom in 5 of
  patients w/ MS
• Multifocal neurologic symptoms/signs
• Characteristic T2-intense lesions in white matter
  on MRI

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Recurrent, spontaneous attacks of vertigo

• Sudden, temporary, and large reversible
  impairment of resting neural activity in one
  labyrinth or its central connections
• Lasts from minutes to hours
• Restoration of normal neural activity, rather
  than compensation

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Menieres disease

• Characteristic fluctuating low-frequency hearing
  loss
• Episodic vertigo
• Roaring tinnitus
• Ear pressure

13
Autoimmune inner ear disease

• May mimic Menieres disease
• Signs/symptoms of systemic involvement
• Elevated ESR, positive ANAs/rheumatoid factor
• Immunosuppression

14
Syphilitic labyrinthitis

• Similar to Menieres disease in signs/symptoms
• Positive VDRL and/or FTA-ABS
• Penicillin, steroids

15
Migraine

• Vertigo occurs in approximately 25 of migraine
  patients
• Hearing loss infrequent
• Headaches that meet International Headache
  Society criteria for migraine
• Treat migraine

16
Vertebrobasilar TIA

• Common cause in older patients w/ risk factors
• Subclavian steal syndrome
• Abrupt, last several minutes
• Other sxs of posterior circulation
• Antiplatelet drugs, anticoagulation

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Recurrent, positional vertigo

• Transient excitation within the vestibular
  pathways triggered by change in position
• Central vs. Peripheral lesions

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Recurrent, positional vertigo peripheral vs.
central

• Peripheral
• Torsional/horizontal
• Latency
• Brief
• Fatigability
• Debris moving in semicircular canal

• Central
• Pure vertical
• No latency
• Persistent
• No fatigability
• Damage to central vestibulo-ocular pathways
• Brainstem or cerebellum

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Benign positional vertigo (BPV)

• Dix-Hallpike test
• 2-10 sec latency
• Torsional/horizontal nystagmus
• Lasts lt 30 sec (fatigability)
• Any deviation from this must raise suspicion for
  a central lesion

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Recurrent, positional vertigo central lesions

• Multiple sclerosis
• Cerebellar tumors
• Medulloblastomas
• Cerebellar atrophy
• Chiari type I malformation

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Near-faint dizziness or presyncope

• Light-headedness before losing consciousness or
  fainting
• Reduced blood flow to the entire brain
• Causes
• Vasovagal
• Orthostatic hypotension
• Volume depletion
• Cardiac arrhythmias, cardiomyopathy, constrictive
  pericarditis, aortic stenosis

22
Psychophysiologic dizziness

• Associated with panic disorder (lifetime
  prevalence of 1.6)
• Hyperventilation ? reduce pCO2 ? cerebral
  vasoconstriction ? decreased cerebral blood flow
• Onset with specific situations (such as public
  places, driving in highways, etc.)

23
Hypoglycemic dizziness

• Complication of insulin/sulfonylurea treatment
• Insulinoma
• Fasting
• Postprandial phenomenon (functional hypoglycemia)

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Disequilibrium

• Sensation of losing ones balance without feeling
  of illusionary movement or impending LOC
• Unsteadiness standing, walking
• Disruption in integration between sensory inputs
  and motor outputs
• Associated with aging

25
Drug-induced dizziness

• Aminoglycosides, cisplatin
• Vertigo, disequilibrium
• Damage to vestibular hair cells
• Antiepileptic
• Carbamazepine, pheytoin, primidone
• Disequilibrium, intoxication
• Tranquilizers
• Barbiturates, benzodiazepines, tricyclics
• Intoxication

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Drug-induced dizziness

• Antihypertensives/diuretics
• presyncope
• Alcohol
• Intoxication ? CNS depression
• Disequilibrium ? cerebellar toxicity
• Positional vertigo ? change in cupula specific
  gravity

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Treatment medical

• Best therapy treating the underlying disease
• Indication for symptomatic therapy
• Illness is not readily treatable
• Treatment must be continued for a long period
  before improvement
• Severe and prolonged vertigo

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Treatment medical

• Acute severe vertigo
• Promethazine (antihistamine) sedative (),
  antiemetic ()
• Diazepam sedative (), antiemetic ()
• Nausea vomiting
• Prochlorperazine (phenothiazine)
• Metoclopramide (benzamide)
• Chronic recurrent vertigo
• Meclizine (antihistamine)
• Dimenhydrinate (antihistamine)

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Treatment surgical

• Conservative surgery
• Shunt surgery (decompress endolymphatic sac)
• Effective in 75 of cases
• Selective section of vestibular division of CN
  VIII
• Effective in gt90 of cases
• lt10 significant hearing loss
• Abnormal vascular loop at the brainstem insertion
  of CN VIII

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Treatment surgical

• Destructive surgery
• Labyrinthectomy
• Complete destruction of the end organ
• Extremely high cure rate
• Cost destruction of all hearing in the involved
  ear

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Vestibular rehabilitation

• Process of compensation
• Requires
• Intact vision depth perception
• Normal proprioception
• Intact sensation in lower limbs
• Graded increase in demand for central
  compensation of vestibular input