脑梗死后运动性失语患者语言中枢的fMRI评价

目的评价脑梗死后运动性失语患者语言中枢的激活特点。方法采用1．5T磁共振扫描仪对15例脑梗死后运动性失语患者及15例正常中老年志愿者行组块设计的词语联想任务fMRI检查。采用SPM2软件进行预处理和统计分析，经组内和组间分析获得两组激活图及组问的差异图，观察有统计学意义的体素所在的脑区。结果最终10例患者符合实验要求并纳入研究，选取10if0年龄、性别相匹配正常男性作为对照组。对照组词语联想任务脑激活区主要包括Broca区及其镜像区、辅助运动区、左侧岛叶前部等脑区。患者组脑激活区主要包括左侧额中回、左顶下小叶、右侧额下回、辅助运动区等脑区。对照组激活高于患者组的脑区为左侧额下回后部；未见患者组激活高于对照组的脑区。结论脑梗死后运动性失语患者左侧额下回后部（Broca区）激活程度减低或消失，运动性语言中枢的损伤导致了失语症的发生。

Functional MRI evaluation on linguistic center in patients with expressive aphasia after cerebral infarction

Objective： To evaluate the brain activation in patients with expressive aphasia after cerebral infarction. Materials and Methods： Fifteen patients suffering from expressive aphasia after cerebral infarction and 15 normal middle-old aged subjects were recruited in this study. All patients and subjects received block-designed category-member generation task fMRI. SPM2 software was used to process fMRI data. Intra- and inter-group analysis was performed to obtain activated mapping in of two groups and different mapping between two groups. MNI coordinate and activated intensity of the brain regions were recorded. Results： Ten male patients and ten male controls were selected after head motion and machine noise had been ruled out. Activated regions of the control group included Broca＇s area, right Broca＇s homologue area, supplement motor area （SMA）, left anterior insula, left superior temporal gyms and left precentral gyms. Activated regions of the patient group included left middle frontal gyms, postcentral gyms, inferior parietal lobule, precuneus lobe, right inferior frontal gyrus, bilaterial precentral gyrus, insula, thalamas,striatum, SMA and cerebellum. When contrast to the patients group, only the posterior part of left inferior frontal gyrus showed activation in control group. There was no significant activation when patients group contrast to control group. Conclusion： Compared with normal middle-old aged controls, the activation level of the posterior part of left inferior frontal gyms （Broca＇s area） declined or disappeared in patients with expressive aphasia after cerebral infarction, which suggest that the damage to the Broca＇s area has led to the occurrence of expressive aphasia.