For a quantitative comparison of images obtained during (99m)Tc-hexamethylpropylene amine oxime (HMPAO) single-photon emission computed tomography (SPECT), brain activity values are usually normalized to a reference region. In studies of Alzheimer-type dementia (ATD), the cerebellum is often used as a reference region, assuming that it is spared any major pathological involvement. Statistical parametric mapping (SPM) may enhance the evaluation of SPECT scans in ATD patients. However, current SPM software only allows scaling to average whole brain activity (i.e., global normalization). The aim of this study was to develop an easily applied, objective, and reproducible method for determining average cerebellar tracer uptake so that images can be scaled specifically to cerebellar activity prior to the performance of SPM analysis. We also investigated whether cerebellar normalization increases the sensitivity and specificity of SPM analysis of ATD patients compared with global normalization.

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1193 - 1202


Aged, Aged, 80 and over, Alzheimer Disease, Brain, Brain Mapping, Cerebellum, Depressive Disorder, Female, Humans, Image Processing, Computer-Assisted, Male, Mathematical Computing, Mental Status Schedule, Middle Aged, ROC Curve, Reference Values, Reproducibility of Results, Technetium Tc 99m Exametazime, Tomography, Emission-Computed, Single-Photon