Labyrinthitis

Description

• AKA Vestibular Neuritis with hearing loss
• Inflammatory disorder of the inner ear
• Often viral inflammation of vestibular portion of CN VIII
• Inflammation decreases afferent firing from the labyrinth
  • CNS interprets the decreased signal as head rotation away from the diseased labyrinth
  • The imbalance in firing from the labyrinth results in spontaneous nystagmus with fast phase away from the pathologic side
• Benign, self-limited
• Unilateral vestibular dysfunction
• Causes balance disorders and vertigo, and may be associated with hearing loss and tinnitus
• Peak onset 30–60 yr old
• Associated with viral upper respiratory tract infection in 50% of patients
• Symptoms predominantly with head movement but can persist at rest
• Recovery phase gradual over weeks to months

Etiology

• 3 most common causes of peripheral vertigo include, benign paroxysmal positional vertigo (BPPV), Ménière disease, and labyrinthitis
• Labyrinthitis:
  • Serous: Viral or bacterial
  • Suppurative: Bacterial
  • Autoimmune: Wegener's or polyarteritis nodosa
  • Vascular ischemia
  • Head injury or ear trauma
  • Medications:
    • Aminoglycosides, loop diuretics, antiepileptics (phenytoin)
  • Allergies
  • Chronic
• BPPV:
  • Dislodgement of otoconia debris:
    • Idiopathic: 49%
    • Posttraumatic: 18%
    • Sequela of labyrinthitis: 15%
    • Sequela of ischemic insult

• Suppurative and serous labyrinthitis:
  • Usually secondary to acute otitis media, mastoiditis, or meningitis
• BPPV:
  • Onset 1–5 yr of age
  • Symptoms: Abrupt onset of crying, nystagmus, diaphoresis, emesis, ataxia
  • Recurrences for up to 3 yr
  • Migraine–BPPV complex is the most common etiology of pediatric vertigo
• Ménière disease:
  • Rare before 10 yr of age