Individual Classification of Mild Cognitive Impairment Subtypes by Support Vector Machine Analysis of White Matter DTI

• Published in: American journal of neuroradiology : AJNR Vol. 34; no. 2; pp. 283 - 291
• Main Authors: Haller, S., Missonnier, P., Herrmann, F.R., Rodriguez, C., Deiber, M.-P., Nguyen, D., Gold, G., Lovblad, K.-O., Giannakopoulos, P.
• Format: Journal Article
• Language: English
• Published: United States American Society of Neuroradiology 01.02.2013
• Subjects: Aged; Amnesia - classification; Amnesia - diagnosis; Anisotropy; Brain; Cognitive Dysfunction - classification; Cognitive Dysfunction - diagnosis; Diagnosis, Differential; Diffusion Tensor Imaging - methods; Evidence-Based Medicine Level 2; Female; Humans; Leukoencephalopathies - classification; Leukoencephalopathies - diagnosis; Male; Middle Aged; Nerve Fibers, Myelinated - pathology; Neuropsychological Tests; Prospective Studies; Support Vector Machine
• ISSN: 0195-6108; 1936-959X; 1936-959X
• DOI: 10.3174/ajnr.A3223

MCI was recently subdivided into sd-aMCI, sd-fMCI, and md-aMCI. The current investigation aimed to discriminate between MCI subtypes by using DTI. Sixty-six prospective participants were included: 18 with sd-aMCI, 13 with sd-fMCI, and 35 with md-aMCI. Statistics included group comparisons using TBSS and individual classification using SVMs. The group-level analysis revealed a decrease in FA in md-aMCI versus sd-aMCI in an extensive bilateral, right-dominant network, and a more pronounced reduction of FA in md-aMCI compared with sd-fMCI in right inferior fronto-occipital fasciculus and inferior longitudinal fasciculus. The comparison between sd-fMCI and sd-aMCI, as well as the analysis of the other diffusion parameters, yielded no significant group differences. The individual-level SVM analysis provided discrimination between the MCI subtypes with accuracies around 97%. The major limitation is the relatively small number of cases of MCI. Our data show that, at the group level, the md-aMCI subgroup has the most pronounced damage in white matter integrity. Individually, SVM analysis of white matter FA provided highly accurate classification of MCI subtypes.