Vestibular Migraine

VM: Introduction & Epidemiology - Dizzying Stats & Facts

• Episodic vertigo linked to migraine history or associated migrainous features (e.g., headache, photophobia, phonophobia) during ≥50% of vestibular episodes.
• A leading cause of recurrent spontaneous vertigo.
• Prevalence: ~1-3% of general population; higher (up to 5%) in dizziness/headache clinics.
• Peak onset: 30-50 years.
• More common in women (F:M ratio ~3-5:1).
• Strong association: ~50% of migraineurs report episodic vertigo.

⭐ VM is the most common neurological cause of vertigo and the second most common vestibular diagnosis overall after BPPV (Benign Paroxysmal Positional Vertigo).

VM: Pathophysiology - The Brain's Vertigo Vibes

• Migraine Overlap: Shares mechanisms with migraine headaches.
• Key Drivers:
  • Trigeminovascular system (TVS) activation → ↑ CGRP.
  • Sensitization: Central & peripheral vestibular pathways.
  • Cortical Spreading Depression (CSD) may contribute.
  • Channelopathies (e.g., $Ca^{2+}$ channels) suspected.

⭐ Calcitonin Gene-Related Peptide (CGRP) is a crucial mediator in VM pathophysiology.

VM: Clinical Features - When Worlds Collide

• Recurrent Vestibular Symptoms: Vertigo (spontaneous, positional, visual) or dizziness with nausea.
  • Moderate to severe intensity.
  • Duration: 5 minutes to 72 hours.
• Migraine Link (IHS Criteria):
  • Current or past history of migraine (with/without aura).
  • ≥50% of vestibular episodes associated with ≥1 migrainous feature:
    • Migrainous headache (unilateral, pulsating, photophobia/phonophobia).
    • Photophobia AND Phonophobia.
    • Visual aura.
• Not better accounted for by another diagnosis.

⭐ Vestibular symptoms can occur before, during, after, or entirely without headache_._

VM: Diagnostic Criteria - The Migraine Maze Map

• Definitive VM (Barany Society & IHS):
  • A. ≥ 5 episodes: vestibular symptoms (mod/severe), duration 5 min - 72 hrs.
  • B. Migraine history (ICHD: with/without aura).
  • C. ≥ 50% of vestibular episodes show ≥ 1 migraine feature:
    • Migrainous headache (e.g., unilateral, pulsating).
    • Photophobia AND phonophobia.
    • Visual aura.
  • D. Not better explained by another vestibular/ICHD diagnosis.

⭐ Vestibular migraine is a common cause of recurrent spontaneous vertigo, often underdiagnosed.

VM: Differential Diagnosis - Spotting the Impostors

• Meniere's: Fluctuating hearing loss, tinnitus, aural fullness. VM: normal hearing.
• BPPV: Positional, brief (<1 min) vertigo. Positive Dix-Hallpike.
• Vestibular Neuritis/Labyrinthitis: Acute, severe vertigo (days). Neuritis: hearing preserved; Labyrinthitis: hearing loss.
• TIA/Stroke: Sudden, neuro deficits (diplopia, dysarthria), vascular risks.
• Anxiety: Situational, panic symptoms, normal vestibular exam.
• PPPD: Chronic non-vertiginous dizziness, motion/visual sensitivity.

⭐ Unlike Meniere's, VM typically shows NO progressive hearing loss; audiometry is normal interictally.

VM: Management Strategies - Steering Clear of Spins

• Acute Rx Focus: Rapid relief of vertigo, nausea, headache.
  • Examples: Ondansetron, Sumatriptan, Diazepam (short-term).
• Prophylactic Rx Focus: Reduce attack frequency & severity.
  • Key Meds: Propranolol, Flunarizine, Amitriptyline, Topiramate.
  • Non-pharma: Consistent VRT, dietary trigger management (e.g., avoid MSG, aged cheese).

⭐ Flunarizine, a calcium channel blocker, is a commonly used prophylactic agent for vestibular migraine; monitor for extrapyramidal symptoms and weight gain.

High-Yield Points - ⚡ Biggest Takeaways

• Most common cause of recurrent spontaneous vertigo in adults.
• Diagnosis by IHCD-3 criteria: ≥5 episodes of vestibular symptoms (5 min-72 hrs), with migraine history.
• ≥50% of episodes must have migrainous features (headache, photophobia, phonophobia, visual aura).
• Nystagmus is variable; audiovestibular tests often normal between attacks.
• Management: migraine prophylactic medications (beta-blockers, TCAs, topiramate) and lifestyle changes.
• Acute attacks: triptans, antiemetics/vestibular suppressants.