Brain metabolism in Alzheimer disease and vascular dementia assessed by in vivo proton magnetic resonance spectroscopy

摘要: Proton magnetic resonance spectroscopy (MRS) allows the assessment of various cerebral metabolites non-invasively in vivo. Among 1H MRS-detectable metabolites, N-acetyl-aspartate and N-acetyl-aspartyl-glutamate (tNAA), trimethylamines (TMA), creatine phosphate (tCr), inositol (Ins) glutamate (Gla) are particular interest, since these moieties can be assigned to specific neuronal glial metabolic pathways, membrane constituents, energy metabolism. In this study on 94 subjects from a memory clinic population, MRS results (single voxel STEAM: TE 20 ms, TR 1500 ms) above were assessed for five different brain regions probable vascular dementia (VD), Alzheimer's disease (AD), age-matched healthy controls. both VD AD, ratios tNAA/tCr decreased, which may attributed atrophy loss, Ins/tCr-ratios increased indicating either enhanced gliosis or alteration However, topographical distribution alterations diseases differed, revealing temporoparietal pattern AD global, subcortically pronounced VD. Furthermore, patients suffering (VD) had remarkably TMA/tCr ratios, potentially due ongoing degradation myelin. Thus, obtained by vivo allow insights into pathophysiology dementias useful diagnostic classification.