A 45-year-old Japanese man, who had had bilateral visual disturbance due to Vogt-Koyanagi-Harada (VKH) disease 17 years before entry, was admitted to this hospital because of headache, vertigo and vomiting. On examination at entry, no abnormalities except for poliosis, patches of vitiligo on his left shin, sunset glow fundus, and positional nystagmus with Frenzel glasses were found. Laboratory data other than leukocytosis and elevated level of gamma-GTP were normal and the results of brain CT scan were within normal limits. On the following day, diplopia was developed and the neurological symptoms including loss of bilateral visual acuity, Horner's syndrome on the right side, right facial palsy, bilateral sensorineural hearing disturbance, palsy of the soft palate on the right side with swallowing difficulty, and dissociated sensory disturbance on the right face and the upper and lower extremities on the left side appeared with a few days. He couldn't get up. The cerebrospinal fluid (CSF) was clear and had pleocytosis with normal sugar content. The protein, immunoglobulin G and myelin basic protein (MBP) were elevated but the tests for oligoclonal band and antiviral antibodies were negative. Brain CT scan showed low density areas in right cerebellar hemisphere and in left putamen without abnormality with contrast material and evoked potentials were normal. Prednisolone was prescribed and his symptoms were subsided but his gait remained ataxic. Magnetic resonance imaging (MRI) 4 months later showed an atrophy of the lower half of bilateral cerebellar hemisphere supplied by posterior inferior cerebellar artery, suggesting cerebellar infarction, and high intensity areas on T2 image in bilateral cerebral white matters, basal ganglia, and left cerebral peduncle.(ABSTRACT TRUNCATED AT 250 WORDS)