Construction of Brain Structural Connectome Using PROPELLER Echo-Planar Diffusion Tensor Imaging with Probabilistic Tractography: Comparison with Conventional Imaging
Brain structural analysis has been widely utilized to investigate brain network alterations caused by diseases. However, susceptibility distortions have been shown to influence tracking results and may detrimentally affect structural connectivity networks. Hence, the purposes of this study were (a) to reduce susceptibility distortions in brain structural networks by using diffusion tensor imaging with PROPELLER echo-planar imaging (pDTI), (b) to compare the differences in brain structural networks between this technique and conventional DTI with single-shot echo-planar imaging (ssDTI), and (c) to investigate sex differences in brain structural networks according to the two techniques. Forty healthy subjects (M/F = 20/20, age = 20–22 y/o) with no history of neurological disease participated in this study. For each participant, the two techniques were utilized to acquire imaging data from a 3.0 T MR scanner. Structural connectivity was statistically compared between these two techniques, as well as between male and female subjects. In connectivity analysis, the pDTI generally had significantly high connectivity between most cortical regions, whereas it exhibited significantly lower connectivity than ssDTI only in regions near the frontal, occipital, and brain stem areas. Furthermore, both techniques revealed consistent sex differences except in regions with susceptibility distortions. We concluded that pDTI might be a suitable alternative technique for investigating alterations in brain structural networks in regions with susceptibility distortions.