Imaging of the patient in CASE 2-4. Amyloid imaging showed diffuse cortical and subcortical signal consistent with Alzheimer disease (not shown). A, Flortaucipir F 18 positron emission tomography (PET) shows a classic Alzheimer disease–like pattern aside for milder medial temporal lobe involvement (top panel). Flortaucipir F 18 PET images show the standardized uptake value ratio (SUVR) of tau, where warmer colors (yellow, red, and orange) indicate more tau uptake. B, Sagittal volumetric MRI presented in three-dimensional space shows more pronounced atrophy of the medial and lateral frontal lobes bilaterally with relative medial temporal lobe sparing; warmer colors (yellow, red, and orange) indicate areas of greater gray matter atrophy.