The syndrome of ataxia, areflexia and ophthalmoplegia, or Miller-Fisher 
syndrome, has been considered to be a variant of Guillain-Barré syndrome with 
pathology restricted to the peripheral nervous system. A patient with 
Miller-Fisher syndrome and bilateral demyelinating optic neuropathy suggesting 
associated central nervous system pathology is presented. Clinical and 
experimental evidence regarding the association of central and peripheral 
nervous system demyelination is reviewed.