MRI-guided SPECT perfusion measures and volumetric MRI in prodromal Alzheimer disease

Abstract

Objective: To identify group differences in the prodromal phase of Alzheimer disease (AD) using quantitative single-photon emission computed tomography (SPECT) perfusion and magnetic resonance imaging (MRI) volume measures within specific volumes of interest. Setting: Gerontology research unit. Participants: There were 17 healthy controls, 56 non-demented patients with memory problems who did not develop AD during 3 to 5 years of follow-up (questionables), and 27 nondemented patients with memory problems who developed AD during follow-up (converters). Methods: A Tc 99m hexamethylpropyleneamine oxime SPECT study and an MRI were performed in each participant at baseline. Mean SPECT activity concentration and MRI volume were estimated within 9 structures: rostral anterior cingulate, caudal anterior cingulate, posterior cingulate, hippocampus, entorhinal cortex, basal forebrain, temporal horn, amygdala, and the banks of the superior temporal sulcus. Data were analyzed using overall and pairwise discriminant analysis, and performance in pairwise group discrimination was measured using correlated receiver operating characteristic curve analysis. Results: The overall (3-group) discriminant function was significant for SPECT (F test, P