White matter pathology likely contributes to the pathogenesis of bipolar disorder (BD). Most studies of white matter in BD have used diffusion tensor imaging (DTI), but the advent of more advanced multi-shell diffusion MRI imaging offers the possibility to investigate other aspects of white matter microstructure. Diffusion kurtosis imaging (DKI) extends the DTI model and provides additional measures related to diffusion restriction. Here, we investigated white matter in BD by applying whole-brain voxel-based analysis (VBA) and a network-based connectivity approach using constrained spherical deconvolution tractography to assess differences in DKI and DTI metrics between BD (n = 25) and controls (n = 24). The VBA showed lower mean kurtosis in the corona radiata and posterior association fibers in BD. Regional differences in connectivity were indicated by lower mean kurtosis and kurtosis anisotropy in streamlines traversing the temporal and occipital lobes, and lower mean axial kurtosis in the right cerebellar, thalamo-subcortical pathways in BD. Significant differences were not seen in DTI metrics following FDR-correction. The DKI findings indicate altered connectivity across cortical, subcortical and cerebellar areas in BD. DKI is sensitive to different microstructural properties and is a useful complementary technique to DTI to more fully investigate white matter in BD.

白质病理学可能有助于双相情感障碍 (BD) 的发病机制。大多数对 BD 中白质的研究都使用了扩散张量成像 (DTI)，但更先进的多壳扩散 MRI 成像的出现为研究白质微观结构的其他方面提供了可能性。扩散峰度成像 (DKI) 扩展了 DTI 模型，并提供了与扩散限制相关的额外措施。在这里，我们通过应用基于全脑体素的分析 (VBA) 和基于网络的连接方法，使用约束球形反卷积纤维束来评估 BD ( n  = 25) 和对照组之间 DKI 和 DTI 指标的差异，研究了 BD 中的白质。 n = 24)。VBA 显示 BD 中辐射冠和后联合纤维的平均峰度较低。连接性的区域差异表现为穿过颞叶和枕叶的流线的平均峰度和峰度各向异性较低，BD 中右侧小脑、丘脑-皮层下通路的平均轴向峰度较低。FDR 校正后 DTI 指标未见显着差异。DKI 发现表明 BD 中皮质、皮质下和小脑区域的连接发生了改变。DKI 对不同的微观结构特性敏感，是 DTI 的一种有用的补充技术，可以更全面地研究 BD 中的白质。