Case 05 of 8 · Clinician · Central causes

Acute vertigo in a patient with vascular risk factors

A 64-year-old on warfarin presents with three hours of vertigo and the central HINTS pattern.

CASE VIGNETTE

A 64-year-old man with hypertension and atrial fibrillation (on warfarin, INR 2.4) presents to the emergency department with three hours of sudden-onset spinning vertigo, nausea, and unsteadiness. He cannot stand without support.

On bedside examination there is a left-beating horizontal nystagmus in primary gaze that becomes right-beating when he looks to the right (direction-changing nystagmus). The bedside head-impulse test is normal — no catch-up saccades — on both sides. Alternate cover testing reveals a 4-prism-diopter right hypertropia on uncovering the right eye (skew deviation). Truncal stability is severely impaired — he cannot sit unsupported.

Hearing is grossly normal. Speech is normal. Limb power and coordination are normal aside from inability to walk. Bedside DVA shows mild symmetric loss of two lines.

MRI with diffusion-weighted imaging at 6 hours after symptom onset shows a small right cerebellar infarct in the territory of the posterior inferior cerebellar artery (PICA).

DVA SIGNATUREMild

Posterior circulation stroke — right cerebellum (PICA)

DVA loss: Mild symmetric loss of two lines (~0.2 logMAR) in both directions
Laterality: Symmetric — DVA does not localise the lesion in central disease
Asymmetry: None — the absence of asymmetry would mislead a clinician relying on DVA alone
Corroborating tests: INFARCT-positive HINTS · severely impaired truncal stability · MRI DWI confirms right cerebellar infarct

Key signature: DVA does not contribute to the central-vs-peripheral question. The HINTS exam plus additional central signs is the standard. Reliance on DVA here would have wrongly reassured the clinician.

Test-battery findings

DVA — bilateral	Mild symmetric ~0.2 logMAR loss both directions
Nystagmus	Direction-changing — left-beating in primary gaze, right-beating on right gaze
Bedside HIT	Normal bilaterally (no catch-up saccades) — INFARCT 'I'
Test of skew	Positive — right hypertropia on uncovering — INFARCT 'RC'
Truncal stability	Severely impaired — cannot sit unsupported
Hearing	Normal
MRI DWI	Right PICA territory infarct (positive at 6 h)

Question

Which feature of this presentation is the strongest single signal that the lesion is central rather than peripheral?

References

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Posterior circulation stroke — right cerebellum (PICA)

Test-battery findings

Question

Further reading

References