On videonystagmography (VNG), a patient with right peripheral vestibular lesion would be expected to show:

• A Direction-changing nystagmus on gaze testing and abnormal smooth pursuit
• B Upbeat nystagmus that worsens with fixation
• C Spontaneous nystagmus beating toward the right (toward the lesion) with fixation suppression
• D Spontaneous nystagmus beating toward the left (away from the lesion) with no gaze suppression ✓

Explanation

In acute right peripheral vestibular loss, the tonic firing of the right labyrinth is diminished, and the intact left labyrinth drives the eyes slowly toward the right (slow phase) with corrective fast phase toward the left — producing left-beating spontaneous nystagmus (Alexander's law applies: nystagmus increases on gaze toward the fast phase). Crucially, peripheral nystagmus is suppressed by visual fixation. Central nystagmus does not suppress with fixation and may be direction-changing or vertical.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

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Written and medically reviewed by the StethoPrep medical team.