Deng Xiaofeng, Yin Hu, Zhang Yan, Zhang Dong, Wang Shuo, Cao Yong, Li Maogui, Wang Bo, Zong Fangrong, Zhao Jizong
Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, China (X.D., H.Y., Y.Z., D.Z., S.W., Y.C., M.L., J.Z.).
China National Clinical Research Center for Neurological Diseases, Beijing (X.D., H.Y., Y.Z., D.Z., S.W., Y.C., M.L., J.Z.).
Stroke. 2022 May;53(5):1682-1691. doi: 10.1161/STROKEAHA.121.035506. Epub 2021 Dec 1.
Language dysfunction is rarely seen in patients with unruptured brain arteriovenous malformation (AVM) albeit the AVM nidus involving language areas, which provides a unique disease model to study language reorganization. The objective of this study was to investigate the impairment and reorganization patterns and characteristics of language-related white matter in AVMs located at different brain areas.
Thirty-three patients with AVMs involving language areas were prospectively enrolled. Patients were categorized into 3 groups according to the lesion locations: the frontal (14 patients), temporal (15 patients), and parietal groups (4 patients). Thirty age- and sex-matched healthy controls were enrolled as comparison. All participants underwent diffusion tensor imaging scans, and automated fiber quantification method was applied to quantitatively study the difference of segmented language-related white matter connectivity between 3 AVM groups and control group.
Language functions were normal in all subjects according to Western Aphasia Battery test. In the frontal group, fractional anisotropy (FA) value decreased in the left arcuate fascicle and increased in left superior longitudinal fasciculus and uncinate fascicle; in the temporal group, FA values decreased in left inferior fronto-occipital fascicle and inferior longitudinal fascicle and increased in right anterior thalamic radiation and uncinate fascicle; in the parietal group, FA values decreased in left arcuate fascicle and inferior longitudinal fascicle and increased in bilateral anterior thalamic radiations and uncinate fascicles and right inferior fronto-occipital fascicle. In fascicles with decreased FA values, the increase of radial diffusivity was common, and fascicles with increased FA values usually presented along with increased axial diffusivity values.
Remodeling of language-related white matter occurs when traditional language areas are involved by AVM nidus, and its reorganization patterns vary with locations of AVM nidus. Fascicle impairment is mainly caused by the myelin deficits, and its plasticity may be dominated by the axon remodeling procedure.
未破裂脑动静脉畸形（AVM）患者尽管AVM病灶累及语言区，但语言功能障碍却很少见，这为研究语言重组提供了独特的疾病模型。本研究的目的是调查位于不同脑区的AVM中与语言相关的白质的损伤及重组模式和特征。
前瞻性纳入33例AVM累及语言区的患者。根据病变位置将患者分为3组：额叶组（14例）、颞叶组（15例）和顶叶组（4例）。纳入30例年龄和性别匹配的健康对照者作为比较。所有参与者均接受扩散张量成像扫描，并应用自动纤维定量方法定量研究3个AVM组与对照组之间分割的与语言相关的白质连通性差异。
根据西方失语成套测验，所有受试者的语言功能均正常。在额叶组中，左侧弓状束的分数各向异性（FA）值降低，左侧上纵束和钩束的FA值升高；在颞叶组中，左侧额枕下束和下纵束的FA值降低，右侧丘脑前辐射和钩束的FA值升高；在顶叶组中，左侧弓状束和下纵束的FA值降低，双侧丘脑前辐射和钩束以及右侧额枕下束的FA值升高。在FA值降低的束中，径向扩散率增加很常见，而FA值升高的束通常伴随着轴向扩散率值的增加。
当传统语言区被AVM病灶累及，与语言相关的白质会发生重塑，其重组模式因AVM病灶位置而异。束损伤主要由髓鞘缺失引起，其可塑性可能由轴突重塑过程主导。
