BACKGROUND: Methyl bromide is toxic to the central and peripheral nervous systems. Two patients with occupational exposure to this agent are described. CASE: Two cases of previously healthy young men were involved. They had worked in a fumigating plant spraying fruits using methyl bromide for several months before admission. They showed general weakness, severe ataxia, bilateral dysmetria and bilateral lateral gaze limitation. And gaze-evoked nystagmus was observed in one of them. Brain MRI showed symmetrically increased signal intensity lesions including the brainstem, cerebellum and splenium of corpus callosum. After conservative treatment, they gradually improved over the next few weeks. CONCLUSIONS: Symmetry and topography of our patients??clinical and radiographic abnormalities support the proposal that methyl bromide exposure can produce symptoms similar to Bickerstaff's brainstem encephalitis.