FIGURE 3. (A) Good correspondence between PET and SPECT is shown by spatially normalized original images of AD patient (MMSE score = 19, r of z maps = 0.62), particularly with respect to reduced uptake in temporoparietal association cortex (white arrows). (B) Discordance is found in another patient (MMSE score = 21, r = 0.35), with impaired frontal uptake for PET (red arrows) but not for SPECT.