Analysis of Slow Phase Eye Velocity during the Course of an Acute Vestibulopathy

Abstract

Spontaneous nystagmus in acute peripheral vestibular disorders reflects central vestibular imbalance due to the reduction in vestibular nuclear activity on the side of the peripheral damage (Gernandt & Thulin, 1952; Shimazu & Precht, 1966). Phenomena such as Alexander's law (Alexander, 1912) and counterdrifting (Hess, 1983) appear to involve more than an imbalance of central vestibular activity—possibly oculomotor phenomena—but often appear in addition to the spontaneous nystagmus during unilateral peripheral vestibular disorders. As a fist step in the elucidation of these phenomena we felt it important to chart, quantitatively, the characteristics of the slow phase velocity (SPV) of vestibular spontaneous nystagmus at different gaze positions over the course of an acute vestibulopathy.