Geeraert Bryce L, Brooks Brian L, Kirton Adam, Carlson Helen L
Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Canada.
Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada.
Brain Imaging Behav. 2025 Jun 30. doi: 10.1007/s11682-025-01011-y.
Perinatal strokes occur more commonly in the left hemisphere and often impact language areas, yet language disability only occurs in a small proportion of cases. Functional imaging studies investigating language processing have shown that perinatal stroke in the left hemisphere may result in contralesional shifts of activity, but none have investigated the structure of white matter connections in such altered language network conditions. Diffusion tensor imaging and neurite orientation dispersion and density imaging offer robust, microstructurally-sensitive metrics which can richly characterize tracts known to support language function. In a sample of 105 participants aged 6 to 19, 73 participants with perinatal stroke and 32 typically-developing controls, we applied these techniques to evaluate differences in microstructure of the arcuate fasciculus and uncinate fasciculus, two tracts classically associated with language, following perinatal stroke while controlling for age, sex, and lesion volume. We identified widespread differences in microstructure in both hemispheres for the arcuate and uncinate fasciculi in perinatal stroke participants compared to controls. Subtypes of perinatal stroke presented differently, with arterial ischemic stroke lesions showing more structural differences than periventricular infarction lesions. Differences between perinatal stroke subtypes were observed for both tracts in both hemispheres. Overall, we demonstrate that white matter microstructure of bilateral language networks is impacted by unilateral perinatal stroke. These bilateral differences in white matter structure after unilateral injury suggest that neuroplastic mechanisms may operate in both hemispheres during development with possible functional implications that could inform customized patient-centered rehabilitation strategies.
围产期中风更常见于左半球，且常影响语言区域，但语言障碍仅在一小部分病例中出现。研究语言处理的功能成像研究表明，左半球的围产期中风可能导致对侧活动转移，但尚无研究调查在这种改变的语言网络条件下白质连接的结构。扩散张量成像以及神经突方向离散度和密度成像提供了强大的、对微观结构敏感的指标，这些指标可以充分表征已知支持语言功能的神经束。在一个由105名6至19岁参与者组成的样本中，73名围产期中风参与者和32名正常发育的对照组，我们应用这些技术来评估在控制年龄、性别和病变体积的情况下，围产期中风后弓状束和钩状束（两条经典的与语言相关的神经束）微观结构的差异。我们发现，与对照组相比，围产期中风参与者两侧半球的弓状束和钩状束在微观结构上存在广泛差异。围产期中风的亚型表现不同，动脉缺血性中风病变比脑室周围梗死病变表现出更多的结构差异。在两侧半球的两条神经束中均观察到围产期中风亚型之间的差异。总体而言，我们证明单侧围产期中风会影响双侧语言网络的白质微观结构。单侧损伤后白质结构的这些双侧差异表明，神经可塑性机制可能在发育过程中在两侧半球发挥作用，可能具有功能意义，可为以患者为中心的定制康复策略提供参考。
