We report a case of Balo's concentric sclerosis diagnosed in vivo by c
haracteristic MRI changes and stereotactic biopsy. Follow-up after 6 m
onths of immunosuppressive treatment demonstrated virtually complete c
linical remission, reduction of the white matter lesions on MRI and no
rmalisation of regional cerebral glucose metabolism as assessed by pos
itron emission tomography not only in white matter but also in the cer
ebral grey matter structures with input from the affected regions.