Fig. (2) PET features. 18F-Fluoro-D-Glucose Positron Emission Tomography (FDG-PET): brainstem (A); basal ganglia (B); frontal paramedian cortex (C). No signal abnormalities are detectable in the brainstem. Note the bilateral putaminal hypermetabolism (B) associated to a bilateral hypometabolism involving the frontal paramedian cortex, particularly on the right side (C). Images are shown in radiological convention.