Figure 22a.

Patient with vascular dementia. (a) Axial ¹⁸F-FDG PET image shows decreased activity in the bilateral frontal and parietal regions, with the right side being worse than the left. In the proper clinical setting, these findings are suggestive of Alzheimer disease dementia. (b) Corresponding axial MR image shows confluent T2-weighted fluid-attenuated inversion-recovery (FLAIR) white matter areas of hyperintensity extending to the subcortical regions, reflecting extensive ischemic damage without cortical volume loss. Findings at structural and functional imaging are representative of subcortical arteriosclerotic encephalopathy or Binswanger disease.