peripheral-vs-central-vertigo

name

peripheral-vs-central-vertigo

description

Differentiates peripheral from central causes of vestibular dizziness using nystagmus characteristics, Dix-Hallpike findings, hearing loss, and brainstem signs. Use after vestibular dizziness is confirmed and you need to decide whether this is a benign peripheral cause (BPPV, neuritis) or a central cause (stroke, cerebellar lesion) requiring urgent neuroimaging. Trigger phrases: "is this central or peripheral vertigo", "could this be a stroke", "differentiating vestibular neuritis from stroke", "BPPV vs central", "what type of nystagmus".

Peripheral vs Central Vertigo Differentiator

Prerequisite: Dizziness has already been classified as vestibular (worsened by head movement, nystagmus present or Dix-Hallpike positive). Use this skill to determine if the cause is peripheral or central.

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Step 1 — Assess the Nystagmus

Nystagmus is the single most informative bedside sign. Examine for:

1. Spontaneous nystagmus (at rest, eyes forward)
2. Gaze-evoked nystagmus (looking left, right, up, down)
3. Positional nystagmus (after Dix-Hallpike)

Tip: Subtle nystagmus may only be visible with fixation blocked — have the patient gaze through a white sheet of paper held close to the eyes.

Feature	Peripheral	Central
Direction	Unidirectional; fast component toward the normal ear; never reverses	May reverse direction when patient looks in direction of slow component; can be purely vertical or torsional
Type	Horizontal with torsional component; never purely torsional or vertical	Any direction; purely vertical or purely torsional = central sign
Effect of visual fixation	Suppressed by fixation	Not suppressed — persists or worsens with fixation
Postural instability	Mild-moderate; walking preserved	Severe; patient may fall when walking
Deafness / tinnitus	May be present	Usually absent
Other neurologic signs	Absent	Often present (diplopia, ataxia, dysarthria, dysphagia, focal weakness)

🚨 Central red flags in nystagmus:

• Direction-changing nystagmus
• Purely vertical or purely torsional nystagmus
• Nystagmus NOT suppressed by visual fixation

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Step 2 — Perform and Interpret Dix-Hallpike

Technique: Move patient rapidly from sitting → lying with head tilted 45° off the table and rotated 45° to one side. Observe eyes for nystagmus.

Feature	Peripheral (BPPV)	Central
Latent period	2–20 seconds	None (immediate onset)
Duration of nystagmus	< 1 minute	> 1 minute
Fatigability	Fatigues with repetition	Nonfatiguing
Intensity of vertigo	Severe	Less severe, sometimes none

✅ BPPV diagnosis: Typical Dix-Hallpike response (latency 2–20s, duration <1 min, fatigues, severe vertigo) = 80% sensitivity for BPPV

⚠️ Atypical Dix-Hallpike (immediate onset, non-fatiguing, duration >1 min, minimal vertigo) = central cause until proven otherwise

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Step 3 — Look for Brainstem / Cerebellar Signs

Perform a focused neurologic exam:

Central signs (any one of these = flag for neuroimaging):

• Cranial nerve abnormalities (diplopia, facial sensory loss, dysarthria, dysphagia)
• Horner syndrome
• Motor or sensory deficits (especially hemibody)
• Dysmetria on finger-nose or heel-shin testing
• Severely ataxic gait — patient falls or cannot walk
• Skew deviation (vertical misalignment of eyes)
• Abnormal head impulse test (HIT) when combined with direction-changing nystagmus or skew (HINTS exam)

⚠️ Absence of other neurologic signs does NOT fully exclude a central process. Isolated cerebellar strokes can present with dizziness alone.

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Step 4 — Assess Hearing

Finding	Interpretation
Unilateral hearing loss + vertigo	Strongly suggests peripheral cause (labyrinthitis, Ménière's disease)
Tinnitus + ear fullness + recurrent attacks	Ménière's disease — peripheral
No hearing loss	Does NOT exclude peripheral disease
Sudden hearing loss + vertigo	Consider labyrinthine infarct — urgent imaging

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Step 5 — Pattern-Based Diagnosis

Clinical Pattern	Most Likely Diagnosis	Action
Acute prolonged severe vertigo, normal neuro exam, normal HIT	Vestibular neuritis	Peripheral; supportive management
Acute prolonged vertigo + ataxic gait or brainstem signs	Cerebellar/brainstem stroke	Urgent neuroimaging
Recurrent brief positional spells, positive Dix-Hallpike (typical)	BPPV	Epley maneuver
Atypical Dix-Hallpike response + hearing loss	Posterior fossa lesion	Further investigation
Recurrent attacks + hearing loss/tinnitus/fullness	Ménière's disease	Peripheral; refer audiology/ENT
Recurrent unprovoked attacks + migrainous features	Vestibular migraine	Peripheral; neurology/migraine workup

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Clinical Guardrails

• HINTS exam (Head Impulse, Nystagmus direction, Test of Skew) — when all three are assessed together in acute prolonged vertigo, an abnormal HIT + unidirectional nystagmus + no skew = peripheral. Any component suggesting central = neuroimaging urgently.
• "Normal" MRI does not exclude early posterior fossa stroke — MRI within 24–48 hours of cerebellar stroke may be falsely negative. Clinical suspicion should drive management.
• Positional vertigo ≠ BPPV by default — atypical Dix-Hallpike warrants imaging for posterior fossa lesion.
• Vestibular dizziness ≠ peripheral — always complete a neurologic exam before labelling as benign.

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Source: Barton JS. "Approach to the patient with dizziness." UpToDate. Last updated Dec 11, 2025.