Fig. 1

Brain MRI and ¹⁸F-FDG PET/MR examination. A1-A4 First brain MRI at onset showed no apparent cerebral atrophy and abnormal signals on DWI and T2WI. B1-B4 Second brain MRI five years later after onset, revealed atrophy of left parietal lobe, bilateral frontal lobes, and bilateral temporal lobes, but still without high-intensity lesions on DWI and T2WI. C1-C4 ¹⁸F-FDG PET/MR showed hypometabolism of left parietal cortex, bilateral medial prefrontal cortexes (C1, C2), bilateral anterior temporal cortexes (C3), and right putamen nucleus (C4)