Cortical and subcortical chemical pathology in Alzheimer's disease as assessed by multislice proton magnetic resonance spectroscopic imaging.

Abstract

Multislide proton magnetic resonance spectroscopic imaging (1H-MRSI) permits the simultaneous acquisition of N-acetylaspartate (NA), choline (Cho), creatine/phosphocreatine (Cre), and lactate (Lac) signal intensities from four 15-mm slices divided into 0.84-ml single-volume elements. NA is inferred to be a neuron-specific molecule, whereas Cho mainly reflects glycerophosphocholine and phosphocholine, compounds involved in phospholipid metabolism. To assess whether 1H-MRSI could detect a regional pattern of cortical and subcortical involvement in the brain of Alzheimer's disease (AD) patients. 1H-MRSI was performed in 15 patients with probable AD and 15 age-matched healthy controls. Regions of interest (ROIs) were selected from frontal (FC), temporal (TC), parietal (PC), occipital, and insular cortices, subcortical white matter (WM), and thalamus. In AD patients, we found a significant reduction of NA/Cre in the FC, TC, and PC and a significant reduction of Cho/Cre in the WM. This 1H-MRSI study of AD patients shows a regional pattern of neuronal damage in the associative cortices, as revealed by significant reduction of NA/Cre in the FC, TC, and PC, and regional derangement of phospholipid metabolism, as revealed by significant reduction of Cho/Cre in the WM.