Balo病的病理特点是白质髓鞘脱失层与较正常的白质层交叠呈同心圆排列，形成树木年轮或洋葱皮样改变［‘］，故又称同心圆硬化或Balo型白质脑炎，是一罕见的中枢神经系统脱髓鞘性病变，过去必须尸检才能确诊，但近来可依据MRI作为生前诊断。作者等经MRI发现典型同心圆改变的Bal Balo’s disease is characterized by white matter demyelination layer and the more normal white matter layer overlapped concentric arrangement, the formation of tree rings or onion skin-like changes [], it is also known as concentric sclerosis or Balo-type white encephalitis , Is a rare demyelinating disease of the central nervous system that had to be autopsy in order to be diagnosed in the past but has recently been diagnosed on the basis of MRI. The authors found that the typical concentric circles altered by MRI