What are Vestibular syndromes?

Vestibular Syndromes

Vestibular syndromes are distinct patterns of dizziness characterized by their timing, triggers, and associated symptoms, which help clinicians differentiate between peripheral and central causes to guide appropriate management. 1

Classification of Vestibular Syndromes

Vestibular syndromes are classified into four main categories based on timing and triggers:

1. Acute Vestibular Syndrome (AVS)

   • Characterized by acute persistent continuous dizziness lasting days to weeks
   • Usually associated with nausea, vomiting, and intolerance to head motion
   • Common causes include:
     • Vestibular neuritis
     • Labyrinthitis
     • Posterior circulation stroke
     • Demyelinating diseases
     • Posttraumatic vertigo
     • Central paroxysmal positional vertigo 1

2. Triggered Episodic Vestibular Syndrome (t-EVS)

   • Episodic dizziness triggered by specific and obligate actions, usually a change in head or body position
   • Episodes generally last less than 1 minute
   • Common causes include:
     • Benign paroxysmal positional vertigo (BPPV)
     • Postural hypotension
     • Perilymph fistula
     • Superior canal dehiscence syndrome
     • Vertebrobasilar insufficiency 1

3. Spontaneous Episodic Vestibular Syndrome (s-EVS)

   • Episodic dizziness that is not triggered and can last minutes to hours
   • Common causes include:
     • Vestibular migraine
     • Ménière's disease
     • Posterior circulation transient ischemic attack
     • Medication side effects
     • Anxiety or panic disorder 1

4. Chronic Vestibular Syndrome (CVS)

   • Dizziness lasting weeks to months or longer
   • Common causes include:
     • Anxiety or panic disorder
     • Medication side effects
     • Posttraumatic vertigo
     • Posterior fossa mass lesions
     • Cervicogenic vertigo 1

Key Differential Diagnoses

Peripheral Vestibular Disorders

• Benign Paroxysmal Positional Vertigo (BPPV)

  • Characterized by acute, discrete episodes of brief positional vertigo without associated hearing loss
  • Fits the triggered episodic vestibular syndrome criteria given its positional trigger and brief episodic occurrences of vertigo 1

• Ménière's Disease

  • Characterized by discrete episodic attacks with sustained vertigo
  • Associated with fluctuating hearing loss, aural fullness, and tinnitus in the affected ear 1

• Superior Canal Dehiscence (SCD)

  • Differs from BPPV in that vertigo is induced by pressure changes rather than position changes
  • May present with associated conductive hearing loss
  • Diagnosed via computed tomography of the temporal bones or vestibular evoked myogenic potential testing 1

• Perilymph Fistula

  • Produces episodes of vertigo and nystagmus triggered by pressure
  • Can occur after surgery involving the middle ear or mastoid region or spontaneously
  • May be accompanied by fluctuating hearing loss 1

Central Vestibular Disorders

• Posterior Circulation Stroke

  • Can present with acute vestibular syndrome
  • May have associated neurological symptoms
  • Requires urgent evaluation and management 2, 1

• Vestibular Migraine

  • Presents as spontaneous episodic vestibular syndrome
  • Often associated with headache and photophobia 3, 4

• Central Paroxysmal Positional Vertigo

  • Similar to BPPV but with central origin
  • May have downbeating nystagmus on the Dix-Hallpike maneuver 1

Other Vestibular Disorders

• Posttraumatic Vertigo

  • Can present with various clinical manifestations including vertigo, disequilibrium, tinnitus, and headache
  • Symptoms can be due to damage of peripheral or central structures
  • Often complicated by overlay of depression or anxiety 1

• Functional Dizziness

  • Behavioral factors affecting spatial orientation and balance function
  • Strong connectivity among threat/anxiety, vestibular, visual, and somatosensory systems in the brain
  • Affects 30-50% of patients consulting for vestibular symptoms 5

Clinical Approach

• Focus on characterizing the dizziness as true vertigo (sensation of rotation or spinning) versus non-specific dizziness (sensation of disturbed spatial orientation without false sense of motion) 3, 6

• Determine the timing, triggers, and associated symptoms to classify into one of the four vestibular syndromes 3, 1

• Perform a complete otologic examination, including nystagmus assessment and vestibular examination 3, 6

• Use the HINTS Plus examination (Head Impulse test, Nystagmus, Test of Skew with hearing loss assessment) to differentiate between central and peripheral causes 2

Treatment Considerations

• Medication

  • Meclizine is indicated for the treatment of vertigo associated with diseases affecting the vestibular system in adults 7
  • Caution: May cause drowsiness and has potential anticholinergic action 7

• Vestibular Rehabilitation

  • Effective for most vestibular disorders, especially bilateral vestibulopathy and functional dizziness 2, 4

• Other Treatments

  • Specific treatments depend on the underlying cause
  • For functional dizziness: vestibular rehabilitation, cognitive behavioral therapy, and serotonin reuptake inhibitors may be effective 4, 5

Common Pitfalls to Avoid

• Relying solely on the patient's description of "dizziness" without clarifying the exact nature of symptoms 3, 6

• Failing to perform the Dix-Hallpike maneuver and supine roll test in patients with positional symptoms 3

• Missing red flags that require urgent evaluation, including focal neurological deficits, sudden hearing loss, and inability to stand or walk 3, 2

• Not considering stroke in every person with acute vestibular syndrome, as it can act as a harbinger of stroke or impending cerebellar herniation 2