A unique case of sporadic Creutzfeldt-Jacob disease presenting as progressive supranuclear palsy.

We report a Japanese case of sporadic Creutzfeldt-Jakob disease (CJD) presenting as progressive supranuclear palsy. For 2 years after onset, neurological deficits had slowly progressed but neither myoclonus nor periodic synchronous discharge was observed. Diffusion-weighted image (DWI) showed unique high signal lesions in the bilateral frontal cortex, left parietooccipital and occipital cortices, but there was nearly no change eight months later. Needle biopsy revealed deposition of prion protein of a patchy/perivacuolar type with spongiform degeneration. Thus, the phenotype of sporadic CJD seems variable and DWI should be performed, even in atypical cases lacking the characteristics of CJD.