Evaluation of Cerebral Blood Flow in Dementia with Lewy Bodies by 99mTECD SPECT Imaging

Abstract

To clarify differences between dementia with Lewy Bodies (DLB) and Alzheimer’s disease (AD) in the actual clinical setting, we studied sites of decreased cerebral blood flow (CBF) in cases of DLB and AD by 99mT-ECD-SPECT imaging using statistical parametric mapping (SPM8). In addition, the drug sensitivity was analyzed by SPM8. Twentyfive cases were classified as DLB with AD (DLB-w) and 8 cases were DLB without AD (DLB-wo). Sites of decreased CBF in the DLB-w group were observed in the posterior cingulate gyrus, bilateral parietotemporal association areas and the occipital lobe, and these sites resembled the pattern of decreased CBF associated with AD. Among the DLBwo cases, decreased CBF was observed in frontal lobe, anterior cingulate gyrus and occipital lobe. In a comparison of sites of decreased CBF prior to treatment between 15 cases in the group exhibiting drug sensitivity and 18 cases in the group not exhibiting drug sensitivity, the drug sensitivity group exhibited more prominent decreases in CBF in the frontal lobe. In summary, 78% of DLB cases were determined to be complicated with DAT based on SPECT imaging, and the pattern of decreased CBF in these cases resembled that of DAT.