RESUMO
Objective To investigate the feature of cerebral glucose metabolism of Alzheimer's disease (AD)and dementia with lewy bodies (DLB).Methods 28 patients with AD and 25 patients with DLB underwent positron emission tomography (PET)with 18 F-fluorodeoxyglucose (18F-FDG)showing glucose metabolism.The region of interest (ROI)was selected from frontal cortex,temporal cortex,parietal cortex,occipital cortex,cerebellum cortex and corpora striata.The 18 F-FDG metabolism ratios between various cerebral regions and cerebellum cortex were compared as an indicator of regional cerebral glucose metabolic patterns.Results The FDG metabolism ratio of parietal cortex and temporal cortex decreased similarly in AD.The FDG metabolism ratio of frontal cortex,parietal cortex,temporal cortex,occipital cortex,dorsal caudate putamen and caudate nucleus in AD was [(0.861 ± 0.173),(0.625 ± 0.149),(0.598 ± 0.185 ),(0.914 ± 0.214),( 1.030 ± 0.084)and ( 0.997 ± 0.102 )].The FDG metabolism ratio of frontal cortex,parietal cortex,occipital cortex,temporal cortex and corpus striatum decreased similarly in DLB.The FDG metabolism ratio of frontal cortex,parietal cortex,temporal cortex,occipital cortex,dorsal caudate putamen and candate nucleus in DLB was [ (0.538 ±0.147),(0.615 ±0.138),( 0.587 ±0.142),(0.415 ±0.107 ),(0.685 ± 0.094)and (0.547 ± 0.103 )].The FDG metabolism ratio of frontal cortex,occipital cortex and corpus striatum decreased more significantly in DLB than in AD (P＜0.01 ).Conclusion There are discrepancies in cerebral glucose metabolism between AD and DLB.These features may be useful in differential diagnosis of these two kinds of dementia.