We report a case of Balb's concentric sclerosis. In the past, the diag
nosis was usually made post mortem. In this case, we found that CT dem
onstrated only low-density lesions, but not their concentric pattern.
However, MRI showed a striking feature, reminiscent of histopathology
of Balb's concentric sclerosis, and played an important role in antemo
rtem diagnosis of this rare demyelinating disease.