Nystagmus

NystagmusNystagmus is a condition in which the eyes move involuntarily, typically in a rhythmic pattern. Types and Causes of NystagmusNystagmus can be categorized in different ways, including based on age at onset, type of eye movement, or specific cause.There are 2 major categories of nystagmus related to when the disease occurs.Congenital nystagmus is present shortly after birth.Acquired nystagmus begins after 6 months of life.Congenital motor nystagmus is the most common type of congenital nystagmus.This usually occurs by itself, is not associated with any other congenital abnormalities, and does not go away but can lessen with time.Other causes of congenital nystagmus include developmental abnormalities in the eye structures, such as the cornea, lens, retina, and optic nerve, or abnormalities in the visual pathways in the brain.Acquired nystagmus has several medical and neurologic causes, including certain medications, stroke, brain injuries or tumors, and diseases of the vestibular system.When vestibular organs are not functioning normally, the body has a difficult time balancing and may induce nystagmus.A clinician can evaluate for the different causes by taking a thorough history, by physical examination, and sometimes with blood tests and imaging.