[An early-onset case of acute disseminated encephalomyelitis with bilateral thalamic lesions on MRI].

We report the case of 5-year-old girl with acute disseminated encephalomyelitis (ADEM), whose MRI showed bilateral thalamic lesions. She suffered from left optic neuritis and generalized convulsion. Examination of cerebrospinal fluid revealed elevation of mononuclear cells and myelin basic protein (MBP). MRI showed the swelling of left optic nerve and high intensity areas of bilateral thalamus. After methylprednisolone pulse therapy, her visual acuity was dramatically improved and bilateral thalamic lesions were decreased. In childhood, bilateral thalamic lesions were observed in several diseases, such as viral encephalitis. Reye syndrome, Leigh syndrome and acute necrotizing encephalopathy. Demyelinating diseases involving the grey matter were very rare, but we must consider the presence of symmetrical thalamic involvement in patients with ADEM.