Skew deviation is caused by abnormal prenuclear vestibular input to the ocular motor nuclei, most commonly due to brainstem or cerebellar stroke. Other causes include multiple sclerosis and head trauma.
Skew deviation, an eye movement disorder, results from abnormal signals received by the brain's control centers for eye movements due to a variety of causes including strokes in the brainstem or cerebellum, multiple sclerosis, and head injuries.