Background: Semantic dementia (SD).
Objective: To identify the pattern of decline of cerebral glucose metabolism in SD using cerebral (18)F-fluoro-2-desoxy-D-glucose positron emission tomography scanning ((18)F-FDG-PET).
Methods: Eight patients with SD underwent (18)F-FDG-PET at baseline and at re-examination in average 15 months later.
Results: Compared with healthy control subjects, patients with SD showed a significant asymmetrical (left > right) hypometabolism of the temporal lobes, particularly of the anterior poles, at baseline. At follow-up, we observed a deterioration of cognitive abilities. However, in addition to the temporal lobes no other cortical or subcortical region showed a significant reduction of glucose metabolism except the anterior cingulate cortex (pcorr < 0.05).
Conclusion: Subtle functional changes suffice to produce significant neuropsycho- logical deterioration.
Copyright (c) 2006 S. Karger AG, Basel.