Specific SPECT Findings in Alzheimer's Dementia

ABSTRACT

OBJECTIVES: Single photon emission computed tomography is a practical modality for the study of physiologic cerebral activity in vivo. So to improve the diagnostic utility of brain single photon emission computed tomography (SPECT) in Alzheimer's disease (AD). we evaluated an objective method of differentiating patients and healthy elderly controls using a semiquantitive image analysis protocol. METHODS: Supratentorial transaxial perfusion measurements were obtained in frontal, anterior temoral, posterior temporoparietal and occipital cortical areas in both hemispheres, in a baseline population of 14 healthy elderly controls and 19 mild to moderately impaired AD patients as well as 9 cases of vascular dementia. RESULTS: Statistically significant hypoperfusion was noted in both posterior temporoparietal regions of interest in the AD group compared with controls. And also hypoperfusion in left posterior temporoparietal area was found in the vascular dementia group compared with controls. Several correlations between perfusion ratio in some cortical area and MMSE score, BDS score and duration of disease in patients with Alzheimer's dementia. CONCLUSION: We found that all subjects with AD demostrated flow deficits in temporoparietal cortex bilaterally, and that the cortical-to-cerebellar ratio in bilateral temporoparietal region allowed the differentiation of all patients with AD from both controls and from the patients with vascular dementia. And ratio in specific region showed a correlation with cognitive function, disease severity and duration ing the AD group. Single photon emission computed tomography appears to be useful in the differential diagnosis of dementia and reflects clinical features of the disease.