Figure 1: T1-weighted magnetic resonance image of patient 1 showing a large hypointense lesion in left frontal region (a). Lesion is hyperintense on fluid-attenuated inversion recovery image (b). The lesion shows an open ring shaped enhancement after contrast administration (c). In diffusion-weighted image, the lesion is hypointense in the center and shows hyperintense outer rim with more hyperintensity along gray matter side of the lesion (d). Proton magnetic resonance spectroscopy shows glutamate peak at 2.4 parts per million with reversed choline/creatine and choline/N-acetyl aspartate ratios (e).