The oculomotor signs that separate the inner ear from the brain in the dizzy patient — each one moving, with what it localises to and the bedside test that provokes it. The same engine that runs the daily case and the simulator.
Posterior-canal BPPV — the commonest positional vertigo.
Provoked by the Dix-Hallpike after a short latency, up-beating with a torsional component toward the down ear, lasting under a minute and fatiguing on repeat. Treated with the Epley.
Source: AAO-HNS BPPV CPG (2017); StatPearls: BPPV.
Horizontal-canal BPPV — direction-changing on the roll test.
Purely horizontal nystagmus that changes direction as the head is turned to each side on the supine roll test. Geotropic (beats to ground) or apogeotropic variants. Treated with roll or Gufoni maneuvers, not the Epley.
Source: AAO-HNS BPPV CPG (2017); StatPearls: BPPV.
Horizontal-canal BPPV — beats away from the ground (cupula variant).
Direction-changing horizontal nystagmus on the roll test that beats away from the ground (apogeotropic), suggesting a cupulolithiasis variant. Still peripheral — treated with Gufoni or roll maneuvers; the weaker-response side is usually the affected ear.
Source: AAO-HNS BPPV CPG (2017); StatPearls: BPPV.
Vestibular neuritis — one direction, suppressed by fixation.
Spontaneous horizontal nystagmus that beats the same direction in every gaze position and gets stronger without visual fixation. With an abnormal head impulse and no skew, it points to peripheral neuritis.
Source: HINTS exam (Kattah 2009); StatPearls: Vestibular neuritis.
A central red flag — think cerebellar.
Pure downbeat nystagmus with no torsion, no latency, persistent and non-fatigable, not suppressed by fixation. Do not treat as BPPV — refer for a central work-up (e.g. cerebellar or craniocervical-junction cause).
Source: Central positional nystagmus literature; AAO-HNS red-flag guidance.
The fast phase reverses with gaze — central until proven otherwise.
As the eyes move, the fast phase changes direction (right-beating on right gaze, left-beating on left gaze). In acute continuous vertigo this is a central sign — part of the dangerous HINTS pattern.
Source: HINTS exam (Kattah 2009).
Abnormal VOR — reassuringly peripheral in continuous vertigo.
On a rapid head thrust the eyes are dragged off the target, then a corrective (catch-up) saccade brings them back. In acute vestibular syndrome this ABNORMAL result points to a peripheral cause (neuritis), not central.
Source: HINTS exam (Kattah 2009).
A normal impulse in continuous vertigo is the danger sign.
The eyes stay locked on the target through the thrust, with no catch-up saccade. Reassuring in a well patient — but in someone with acute continuous vertigo who cannot walk, a NORMAL impulse is the worrying, central sign.
Source: HINTS exam (Kattah 2009).
Vertical misalignment — specific for central.
On the alternate-cover test the just-uncovered eye makes a small vertical refixation. Skew is the least sensitive but most specific of the three HINTS signs — when present, refer.
Source: HINTS exam (Kattah 2009); Newman-Toker AVS literature.
Stylised teaching animations authored by NeuroDash. Not real-patient recordings, not board-certified, and not reviewed by an outside specialist. Educational only — not medical advice or a diagnosis.