FIGURE 2. A 58-y-old right-handed man had 2-y history of progressive memory loss, which became worse over last 7 mo. His father and three cousins had dementia. Transaxial, sagittal, and coronal slices show marked bilateral, symmetric temporoparieto-occipital hypoperfusion, extending to frontal lobes. Basal ganglia, primary visual cortex, and cerebellum are spared.