Rare disorder, present at birth, in which the optic nerve is underdeveloped, the pituitary gland does not function properly, and often a portion of brain tissue is not formed. De Morsier's Syndrome, also known as septo-optic dysplasia, may cause blindness in one or both eyes and is also often accompanied by
nystagmus and various other symptoms. Some children with De Morsier's Syndrome have normal intelligence, while others may be developmentally delayed, learning-disabled, or mentally retarded. Some symptoms of this disorder can be treated, but the visual impairment usually cannot be corrected. Visual devices, such as a magnifier or a computer designed for visually impaired users, may benefit some people with De Morsier's Syndrome.