title: New understanding on the contribution of the central otolithic system to eye movement and skew deviation.
abstract: The otolith organs consist of the utricle and saccule. The utricle mediates the utriculo-ocular reflex by detecting horizontal head translation and static head tilt. Skew deviation is a vertical strabismus caused by imbalance of the utriculo-ocular reflex pathway and is commonly caused by lesions in the brainstem or cerebellum. It is associated with abnormal utriculo-ocular reflexes including asymmetric reduction of the translational vestibulo-ocular and ocular counterroll responses. Skew deviation is also associated with head position-dependent changes in ocular torsion and vertical strabismus. The reduction in ocular torsion and vertical strabismus when changing from an upright to supine position in skew deviation allows us to devise a new bedside 'upright-supine test' to differentiate skew deviation from fourth nerve palsy and other causes of vertical strabismus.
authors.affiliation: Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, and the Toronto Western Hospital, Toronto, Canada.
authors.forename: A M F
authors.initials: AM
authors.lastname: Wong
mesh_terms: D005133:Eye Movements / Q000502:physiology*; D006801:Humans; D010037:Otolithic Membrane / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology; D013285:Strabismus / Q000503:physiopathology*