Attack Duration as the Primary Differentiator
Vertigo duration alone narrows the diagnosis dramatically.
- <60s: BPPV episode (seconds per spell)
- 1–5 d: Neuritis episode (continuous course)
- 20min–12h: Meniere's episode (discrete hours)
- Moderate: Overlap risk (history is essential)
Why duration matters most
Placeholder: duration buckets map cleanly onto three distinct vestibular disorders.
Positional Trigger — the BPPV Hallmark
Head-position change provoking brief vertigo defines BPPV.
- Positional: Trigger (rolling, looking up)
- Dix-Hallpike: Test (reproduces nystagmus)
- <60s: Duration (per episode)
- Absent: Hearing loss (never a BPPV feature)
Positional mechanism
Placeholder: otoconia debris in semicircular canals cause brief positional spins.
Continuous Days-Long Vertigo — the Neuritis Pattern
Sudden, unrelenting vertigo over days suggests vestibular neuritis.
- Sudden: Onset (often viral prodrome)
- Days: Duration (gradually improving)
- Absent: Hearing loss (distinguishes from labyrinthitis)
- Unidirectional: Nystagmus (horizontal-torsional)
Continuous course
Placeholder: unilateral vestibular nerve inflammation drives constant imbalance.
Episodic Hours With Hearing Symptoms — Meniere's Disease
Vertigo lasting hours with hearing loss and tinnitus signals Meniere's.
- 20min–12h: Duration (per attack)
- Fluctuating: Hearing loss (low-frequency)
- Present: Tinnitus (often unilateral)
- Common: Aural fullness (pre-attack sign)
Endolymphatic hydrops
Placeholder: fluid pressure changes in the inner ear drive episodic attacks.
Associated-Symptom Differentiation Algorithm
Combining duration, trigger, and hearing symptoms yields a diagnosis.
- Duration: Step 1 (seconds/hours/days)
- Trigger: Step 2 (positional or spontaneous)
- Hearing: Step 3 (present or absent)
- 3-way call: Output (BPPV / neuritis / Meniere's)
Decision summary
Placeholder: algorithm combines three history features into one classification.
Placeholder: always confirm with bedside exam findings, not history alone.