NYSTAGMUS

• Medications (meperidine, barbiturates, phenytoin, phenothiazines, etc.).

• Multiple sclerosis.

• Congenital.

• Neoplasm (cerebellar, brainstem, cerebral).

• Labyrinthine or vestibular lesions.

• CNS infections.

• Optic atrophy.

• Other: Arnold-Chiari malformation, syringobulbia, chorioretinitis, menin-geal cysts.