Tony Brune, DO, Departments of Neurology, The Johns Hopkins School of Medicine; Daniel R. Gold, DO, Departments of Neurology, Ophthalmology, Neurosurgery, Otolaryngology - Head & Neck Surgery, The Johns Hopkins School of Medicine
After assessing static binocular visual acuity, dynamic visual acuity (DVA) is determined by repeating the test during horizontal and vertical head shaking at 2-3 Hz. Dynamic visual acuity is most important to test when bilateral vestibular loss is suspected. A loss of at least 4 lines is typical of bilateral vestibular loss (generally horizontally and vertically), and normal patients without vestibular loss should not lose more than 1 line or so on the acuity chart. Patients with unilateral vestibular loss may loss 2-3 lines on the acuity chart (usually horizontal DVA is more impaired than vertical DVA), and this can vary with the chronicity and degree of vestibular loss.
Spencer S. Eccles Health Sciences Library, University of Utah