title: Differences in early and late mild cognitive impairment tractography using a diffusion tensor MRI.
abstract: Diffusion tensor MRI tractography is an imaging tool that can provide information of in-vivo neuronal fiber tracts to assess progress for Alzheimer's disease (AD). In an effort to detect early AD progression, we focused on distinguishing subgroups within mild cognitive impairment (MCI): early MCI and late MCI. Tractography was applied not only to white matter regions but also neighboring gray matter regions known to be affected by AD. Nerve fibers touching the hippocampus, thalamus, and amygdala in both hemispheres were extracted to quantify limbic system fiber connectivity. Two fiber extraction algorithms, fiber assignment by continuous tracking and the Runge Kutta approach, were applied to an AD imaging database. We computed the number of fibers touching regions of interest as the imaging feature. The imaging feature could distinguish between the MCI subgroups. It was also significantly correlated with a known genetic marker for AD, the apolipoprotein E epsilon 4 allele. The number of fibers might be a useful imaging biomarker to complement conventional region of interest-based biomarkers for AD research.
authors.affiliation: aSchool of Electronic Electrical Engineering, Sungkyunkwan University, Suwon bDepartment of Biomedical Engineering, Yonsei University cDepartment of Biomedical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Seung-Hak
authors.initials: SH
authors.lastname: Lee
authors.forename: Jongbum
authors.initials: J
authors.lastname: Seo
authors.forename: Jong-min
authors.initials: JM
authors.lastname: Lee
authors.forename: Hyunjin
authors.initials: H
authors.lastname: Park
mesh_terms: D000368:Aged; D000465:Algorithms; D000544:Alzheimer Disease / Q000175:diagnosis / Q000235:genetics / Q000473:pathology; D053327:Apolipoprotein E4 / Q000235:genetics; D001921:Brain / Q000473:pathology*; D060825:Cognitive Dysfunction / Q000235:genetics / Q000473:pathology*; D016208:Databases, Factual; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D018450:Disease Progression; D005260:Female; D066128:Gray Matter / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D066127:White Matter / Q000473:pathology
chemical_list: D053327:Apolipoprotein E4