Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
China National Clinical Research Center for Neurological Diseases, Beijing, China.
Brain Connect. 2021 Aug;11(6):447-456. doi: 10.1089/brain.2020.0853. Epub 2021 Apr 15.
The corpus callosum (CC) plays a key role in mediating interhemispheric connectivity and developing functional hemispheric asymmetries. The purpose of this study was to investigate the changes in CC microstructure accompanying interhemispheric language reorganization in patients with brain arteriovenous malformations (AVMs). Forty-one patients with an unruptured AVM located in anatomically defined language areas underwent functional magnetic resonance imaging and diffusion tensor imaging. Hemispheric dominance in Broca's area (BA) and Wernicke's area (WA) was assessed separately. Right-sided or bilateral language dominance was classified as atypical lateralization. The CC was segmented into five subregions, and the mean fractional anisotropy (FA) was extracted. The relationship between callosal FA and language lateralization patterns was statistically analyzed. We observed atypical language lateralization in 16 (39.0%) patients. Patients with atypical lateralization exhibited significantly higher mean FA values in the total CC ( = 0.002) and the anterior ( = 0.047), midanterior ( = 0.001), and midposterior ( = 0.043) subregions. Significant interaction effects of BA and WA lateralization were found for FA values in the total CC ( = 0.005) and the midanterior subregion ( = 0.004). These results indicate that AVM patients with atypical language lateralization exhibit higher callosal FA values, reflecting greater interhemispheric connectivity. Our findings contribute additional insights into the understanding of functional and structural plasticity of the human brain under pathological states. Impact statement Brain arteriovenous malformations (AVMs) are congenital lesions that frequently lead to interhemispheric language reorganization. In this study, by combining diffusion tensor imaging and functional magnetic resonance imaging, we investigated the relationship between callosal fractional anisotropy (FA) and language reorganization in patients with AVMs. We found that callosal FA was significantly higher in patients with atypical language lateralization, especially in those with crossed lateralization of Broca's and Wernicke's areas. This study demonstrated the remodeling of the corpus callosum microstructure accompanying language reorganization in AVM patients, providing insights into the structural and functional plasticity of the human brain associated with congenital cerebrovascular disease.
胼胝体（CC）在介导大脑两半球之间的连接和形成功能性大脑偏侧性方面起着关键作用。本研究旨在探讨脑动静脉畸形（AVM）患者大脑两半球之间语言重组时，CC 微观结构的变化。41 例未破裂 AVM 患者位于解剖定义明确的语言区域，接受功能磁共振成像和弥散张量成像检查。分别评估 Broca 区（BA）和 Wernicke 区（WA）的半球优势。将右侧或双侧语言优势归类为非典型侧化。将 CC 分割成五个亚区，并提取平均分数各向异性（FA）。对胼胝体 FA 与语言侧化模式之间的关系进行了统计学分析。我们观察到 16 例（39.0%）患者存在非典型语言侧化。非典型侧化患者胼胝体全段（ = 0.002）、前段（ = 0.047）、中前段（ = 0.001）和中后段（ = 0.043）的平均 FA 值显著较高。在胼胝体全段（ = 0.005）和中前段（ = 0.004）的 FA 值中发现了 BA 和 WA 侧化的显著交互效应。这些结果表明，AVM 患者存在非典型语言侧化，表现出更高的胼胝体 FA 值，反映了更强的大脑两半球间连接。我们的研究结果为理解病理状态下大脑的功能和结构可塑性提供了更多的见解。
影响声明
脑动静脉畸形（AVM）是一种先天性病变，常导致大脑两半球之间的语言重组。在这项研究中，我们通过结合弥散张量成像和功能磁共振成像，研究了 AVM 患者胼胝体分数各向异性（FA）与语言重组之间的关系。我们发现，非典型语言侧化患者的胼胝体 FA 值显著较高，尤其是 Broca 区和 Wernicke 区交叉侧化的患者。这项研究证明了 AVM 患者语言重组时胼胝体微观结构的重塑，为与先天性脑血管疾病相关的大脑结构和功能可塑性提供了见解。
