Analyses of the Disruption of White Matter Integrity in Schizophrenia Using Diffusion Tensor Fiber Tracking with Automatic Construction of Region of Interest

Utako YAMAMOTO, Akifumi HISADA, Tetsuo KOBAYASHI, Shinsuke KITO, Yoshihiko KOGA
Vol. 2 (2013) p. 1-10

The goal of this study was to find feasible indices for quantitative evaluation of sagittal stratum abnormalities in schizophrenic patients, by automatically establishing the region of interest during fiber tracking of a target bundle. We analyzed the sagittal stratum, including the inferior longitudinal fasciculus and the inferior fronto-occipital fasciculus, using a fiber tracking and tractography technique with magnetic resonance diffusion tensor imaging. Diffusion tensor images were acquired from patients with schizophrenia and healthy subjects (controls), group-matched for age, sex, and handedness. We calculated thirteen indices representing the features of the tracked fibers. These were derived from the cross-sectional area of the tracked fibers in the starting area, fractional anisotropy, mean diffusivity, and curvature of the tracked streamline. These indices were compared between patients and control groups, and between the right and left hemispheres. We found significant differences in two indices between the patient and control groups;four indices indicating significant hemisphere effects in the patient group, and three indices showing significant differences between hemispheres in the control group. These results suggest that it may be possible to perform quantitative evaluation of sagittal stratum abnormalities in schizophrenia using these indices.