脑卒中后运动性失语的功能磁共振成像研究

Functional MRI study of the Broca aphasia after cerebral stroke

目的:探讨脑卒中后运动性失语症患者的语言功能恢复机制。方法:应用3T MR扫描仪对6例脑卒中患者失语后及康复后分别进行两次图片命名任务的BOLD fMRI扫描。实验采用组块设计方案,利用SPM5软件的总体线性模型(Generallinear model,GLM)进行后处理产生激活脑区图像。并对所有患者在发病后与康复后的脑内激活分布、大小、强度进行分析与比较。结果:所有患者在失语后左侧大脑半球语言相关脑区激活部分出现激活,其中3例右侧Broca’s镜像区出现激活。而在康复后所有患者的左侧大脑半球语言相关脑区激活增多,激活强度增加,其中左侧Broca’s区均出现激活,右侧Broca’s镜像区激活减弱。结论:失语后优势半球丧失功能的语言区移至对侧镜像区和优势半球未受累语言区的功能重组这两种机制都参与了语言功能恢复的过程,近期以右侧半球为主,远期左侧半球发挥更重要作用。

Objective： To explore the recovery mechanisms of Broca aphasia after cerebral stroke.Methods： Six patients of Broca aphasia from acute stroke were scanned twice in a 3T MR system with block-designed BOLD fMRI sequences,undergoing picture-naming task.Functional images were processed by using SPM5 software with general linear model（GLM） to generate activations.The distributions,dimensions and intensities of activations were compared and analyzed.Results： After aphasia,the language-associated areas in the left hemisphere were shown partially activated.In 3 cases,the activations of Broca＇s area in the right hemisphere were shown.After aphasia recovery,the activation number,dimension and intensity in the left hemisphere increased.The activations of Broca＇s area in the left hemisphere were shown in all the patients.The activations of Broca＇s area in the right hemisphere decreased.Conclusion： Bilateral hemispheres synchronously participate in the process of language recovery.The recovery of language function depends on the functional transfer of right hemisphere at acute stage,and the functional reorganization has more important effect from the left hemisphere at chronic stage.