Early Abnormality of Diffusion-Weighted Magnetic Resonance Imaging Followed by Brain Atrophy in a Case of Gerstmann-Sträussler-Scheinker Disease

A 72-YEAR-OLDMANPREsented with a 1-year historyofprogressive bilateral limb weakness, aphasia, and apathy. Diffusion-weighted magnetic resonance imaging demonstrated hyperintense signal change in the frontal, temporal, occipital, and parietal cortical gyri of the bilateral hemisphere (Figure A) although computed tomographic scan showed no abnormalities (Figure B). The results from cerebrospinal fluid examination were normal except for the elevation of neuron-specific enolase levels (47ng/mL); analysis for 14-3-3 protein was also positive. Prion protein gene analysis revealed a mutation of proline to leucine at codon 102. His condition gradually deteriorated over the next 8 months; he presented with mutism, akinesia, and spastic tetraplegia. Computed tomographic scans performed 2 (Figure C) and 8 months later (Figure D) demonstrated remarkable progression of cortical atrophy in the bilateral frontotemporal lobes and hypodense lesions in the bilateral frontal subcortical area. Gerstmann-Straussler-Scheinker disease is an inherited progressive neurodegenerative disease associatedwithmutations in thepriongene. A substitution of proline to leucine at codon 102 is one of the most frequent mutations associated with Gerstmann-Straussler-Scheinker disease. Diffusion-weighted magnetic resonance imaging aids in the early diagnosis of prion disease as shown by this case.