X-linked infantile nystagmus is associated with mutations of the gene FRMD7, which is located on the X chromosome. Visual-motor syndrome of functional monophthalmus.Types of early-onset nystagmus include the following, along with some of their causes: The affected persons are usually unaware of their spontaneous eye movements, but vision can be impaired depending on the severity of the eye movements. Early-onset nystagmus itself is usually mild and non-progressive. It can be insular or accompany other disorders (such as micro-ophthalmic anomalies or Down syndrome). Nystagmus is also occasionally associated with vertigo.Įxample of congenital (early onset) nystagmusĮarly-onset nystagmus occurs more frequently than acquired nystagmus. Previously considered untreatable, in recent years several drugs have been identified for treatment of nystagmus. Nystagmus may be caused by congenital disorder or sleep deprivation, acquired or central nervous system disorders, toxicity, pharmaceutical drugs, alcohol, or rotational movement. There are two key forms of nystagmus: pathological and physiological, with variations within each type. ![]() The direction of ocular movement is related to the semicircular canal that is being stimulated. Nystagmus occurs when the semicircular canals are stimulated (e.g., by means of the caloric test, or by disease) while the head is stationary. ![]() From here, a signal is relayed to the extraocular muscles to allow one's gaze to fix on an object as the head moves. The semicircular canals in the vestibule of the ear sense angular acceleration, and send signals to the nuclei for eye movement in the brain. In normal eyesight, while the head rotates about an axis, distant visual images are sustained by rotating eyes in the opposite direction of the respective axis. In many cases it may result in reduced or limited vision. People can be born with it but more commonly acquire it in infancy or later in life. ![]() Nystagmus is a condition of involuntary (or voluntary, in some cases) eye movement. Horizontal optokinetic nystagmus, a normal ( physiological) form of nystagmus
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