fig 1.

Images of a 52-year-old man who developed acute left hemiparesis, ataxia, and agitation (case 1).

A, Sagittal view T1-weighted MR image (560/12/2 [TR/TE/excitations]) shows a lesion in a concentric ring pattern in the right centrum semiovale.

B, Coronal view T1-weighted MR image with contrast enhancement shows focal, peripheral enhancement in the lesion.

C, Histopathologic image shows the area that its myelin-spared (⇓) and strictly separated from the demyelinated area, which contains a high number of macrophages (hematoxylin and eosin, original magnification ×125). On the right (Sudan black, original magnification ×500), the demyelinated area and macrophages, including black myelin debris, can be seen (⇑).

D, Coronal view fluid-attenuated inversion recovery image (15000/170/1; inversion time, 2500 ms) shows a residual concentric lesion 13 months after surgery.