Vestibular disorders in (frontal) roll plane

Abstract

The clinical signs, both perceptual and motor, of a vestibular tone imbalance in the roll plane include ocular tilt reaction (OTR), ocular torsion, skew deviation, and tilts of the perceived (subjective) visual vertical (SVV). Complete OTR or skew torsion without head tilt indicates either a unilateral peripheral deficit of otolith and vertical semicircular canal input or a unilateral lesion of “graviceptive” brain-stem pathways from the vestibular nuclei (crossing midline at the pontine level) to the interstitial nucleus of Cajal (INC) in the rostral midbrain. SVV tilts are the most sensitive clinical sign of an acute unilateral brainstem infarction and signify a vestibular tone imbalance in roll. They occur with peripheral or central vestibular lesions from the labyrinth to the vestibular cortex.