The nosological position of the ophthalmoplegia, ataxia and areflexia syndrome: "the spectrum hypothesis".

Two cases of ophthalmoplegia ataxia and areflexia are described, each with undoubted central and peripheral neural affection. It is concluded that the cardinal features are due to brainstem pathology, and support the hypothesis that this syndrome and the post-infectious polyradiculoneuritides represent differing ends of a spectrum which reflects two modes of nervous system reaction to a presumed infective challenge.