Rotational Tests of Vestibular Function

Abstract

Rotational tests are aimed at producing a more natural, precise, repeatable, and broadband evaluation of the vestibular function. Currently, two types of rotation tests are in clinical use: passive whole-body rotation where the stimulus is produced by a motorized chair, and active rotation where the stimulus is produced by voluntary head movements. In both methods, the frequency response of the vestibulo-ocular reflex (VOR) is determined by measuring the eye movements and comparing the head velocity with the slow-phase eye velocity. Rotation tests offer several advantages over other vestibular function tests in patients with bilateral caloric weakness, in young children, or in patients for whom VOR changes have to be assessed over time. In most other patients, rotation tests do not offer a significant advantage because of their low sensitivity to common vestibular abnormalities.