Abstract: Objective To explore the relationship between the changes of corpus callosum related structure and function and motor dysfunction in patients with cerebral infarction (CI). Methods 41 patients with cerebral infarction (CI) admitted to our hospital from March 2022 to September 2025 were selected as the study subjects and included in the CI group.Additionally,41 age- and gender-matched healthy subjects were selected and included in the control group.Diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI) were used to assess the fractional anisotropy (FA) values of the corpus callosum fibers and interhemispheric functional connectivity,and their correlation with FMA scores was analyzed. Results In the hemispheric interconnection group,29 out of 32 corticospinal nerve fiber bundles in the homologous brain regions of the hemispheres showed significantly reduced FA values in the mid-sagittal plane region (P＜0.05).Furthermore,the FA values of these 29 corticospinal fibers were significantly reduced and positively correlated with FMA scores (P＜0.05).The overall functional connectivity between hemispheres was significantly weakened,with 5 connections showing a significant correlation with FMA scores (P＜0.05).Among them,three involved homologous brain regions,which were primary motor cortex (r=0.503,P=0.018),ventral premotor area (r=0.594,P=0.004),inferior frontal gyrus (r=0.482,P=0.028); Two are functional connections of non homologous brain regions,which are the connections between the lateral orbital gyrus of the affected side and the orbital part of the inferior frontal gyrus of the contralateral side (r=0.487,P=0.027),and between the inferior parietal lobule of the affected side and the superior marginal gyrus of the contralateral side (r=0.524,P=0.015). Conclusion After unilateral CI,extensive microstructural damage appeared in the fiber bundles connecting the corpus callosum to the bilateral hemispheres,and the interhemispheric functional connectivity showed an overall weakening.These structural and functional impairments,especially the disruption of connections in sensorimotor related brain regions,are closely related to the severity of motor dysfunction in patients.Dysregulation of the bilateral hemispheric network mediated by the corpus callosum is an important mechanism of movement disorders after CI.

Key words: Cerebral infarction, Corpus callosum, Anisotropy fraction, Functional connectivity, Motor dysfunction

摘要： 目的 探讨脑梗死(CI)患者胼胝体相关结构和功能变化与运动功能障碍的关系。方法 选择2022年3月-2025年9月期间本院收治的CI患者41例作为研究对象,纳入CI组;另选41名年龄、性别匹配的健康受试者,纳入对照组。采用DTI和rs-fMRI评估胼胝体纤维FA值及半球间功能连接,分析其与FMA评分的相关性。结果 CI组半球间同位脑区的32条经胼胝体神经纤维束中29条在中矢状面区域的FA值显著降低(P<0.05),且该29条胼胝体纤维FA值显著降低,且与FMA评分正相关(P<0.05);半球间总功能连接显著减弱,其中5条连接与FMA评分显著相关(P<0.05)。其中,3条涉及同源脑区,分别为初级运动皮质(r=0.503,P=0.018)、腹侧运动前区(r=0.594,P=0.004)、额下回盖部(r=0.482,P=0.028);2条为非同源脑区功能连接,分别为患侧外侧眶回与健侧额下回眶部之间(r=0.487,P=0.027),患侧顶下小叶与健侧缘上回之间(r=0.524,P=0.015)的连接。结论 单侧CI后胼胝体连接双侧半球的纤维束出现广泛微观结构损伤,且半球间功能连接呈现整体性减弱。这些结构与功能的损害,尤其以感觉运动相关脑区的连接中断最为显著,且与患者运动功能障碍的严重程度密切相关。胼胝体介导的双半球网络失调是CI后运动障碍的重要机制。

关键词: 脑梗死, 胼胝体, 各向异性分数, 功能连接, 运动功能障碍