Distinguishing Primary Lateral Sclerosis from Parkinsonian Syndromes with the Help of Advanced Imaging

(Top) Orthogonal ¹⁸F-FDG PET slices showing mild hypometabolism (arrows) in left sensorimotor cortex corresponding to right arm location of cortical homunculus. (Middle and bottom) Transverse slices of dopamine transporter imaging. Both classic ¹²³I-FP-CIT SPECT and high-resolution, selective ¹⁸F-PE2I PET showed normal presynaptic dopaminergic uptake. Images are in radiologic orientation. SUVR = SUV ratio.