Loss of Olfactory Tract Integrity Affects Cortical Metabolism in the Brain and Olfactory Regions in Aging and Mild Cognitive Impairment

摘要

Olfactory dysfunction is an early feature of Alzheimer disease. This study used multimodal imaging of PET and ¹⁸F-FDG combined with diffusion tensor imaging (DTI) to investigate the association of fiber tract integrity in the olfactory tract with cortical glucose metabolism in subjects with mild cognitive impairment (MCI) and normal controls. We hypothesized that MCI subjects would show loss of olfactory tract integrity and may have altered associations with glucose metabolism.MethodsSubjects diagnosed with amnestic MCI (n = 12) and normal controls (n = 23) received standard brain ¹⁸F-FDG PET and DTI with 32 gradient directions on a 3-T MR imaging scanner. Fractional anisotropy (FA) maps were generated. Voxelwise correlation analysis of olfactory tract FA values with ¹⁸F-FDG PET images was performed.