[Bickerstaff's brainstem encephalitis with positive findings on head MRI--case report].

We report a case of Bickerstaff's brainstem encephalitis (BBE) with positive findings on head MRI. Abnormal lesions on head MRI were detected in approximately 30% cases of BBE. An 81-year-old female presented with disturbance of consciousness (Japan Coma Scale 200), ophthalmoplegia (downward deviation) and tetraplegia. Cerebrospinal fluid examination revealed mild pleocytosis 244 cells in 3 microl of CSF with normal glycorrhachia. Head MRI showed high-intensity abnormalities extending over the brain stem. The patient was diagnosed with BBE. It was thought that her symptoms were believed to arise from the lesion in reticular formation, rostral interstitial nucleus of the medial longitudinal fasciculus, and the pyramidal tract. At discharged after 1 month, she had no sequela.