镜像同伦功能连接在轻度认知障碍脑功能检查中的应用

目的：利用静息态功能磁共振成像（rs-fMRI）基于体素的镜像同伦连接（VMHC）及基于种子的功能连接（FC）的方法探讨轻度认知障碍（MCI）患者脑网络异常改变。方法：收集MCI患者29 例纳入MCI组,收集性别、年龄和文化程度匹配的健康对照者29 例纳入HC组。两组受试对象均接受相关精神量表分析及3.0T磁共振扫描。利用VMHC方法分析两组受试对象全脑镜像同伦连接差异,采用独立样本t 检验比较两组VMHC值差异,然后以VMHC差异脑区作为种子分析其与全脑功能连接差异。结果：MCI组双侧颞上回VMHC值较HC组增加（差异体素41个,t =4.264,P ＜0.05）,MCI组左侧颞上回与右侧梭状回、左侧额中回、右侧额中回的功能连接较HC组增强（P ＜0.05）,右侧颞上回与左侧梭状回、左侧颞中回、右侧额下回、左侧楔叶、左侧枕中回的功能连接增强（P ＜0.05）。结论：MCI患者静息状态下双侧颞上回镜像同伦功能连接增强,提示MCI可能存在感觉语言中枢损害并伴有对侧中枢代偿性功能增强。

Application of voxel-mirrored homotopic connectivity on fMRI in mild cognitive impairment

Objective: To explore the abnormal changes of brain functional connectivity in patients with mild cognitive impairment (MCI) by resting-state functional magnetic resonance imaging (rs-fMRI) using voxelmirror homotopic connectivity (VMHC) and seed-based functional connectivity (FC). Methods: Twenty-nine patients with MCI (MCI group) and twenty-nine healthy controls with similar gender, age and education level(HC group) were enrolled. All participants in both groups underwent the analysis of related mental scales and 3.0T MRI scan. The difference in functional connectivity between the two groups was analyzed by VMHC and FC.The difference in VMHC value between the two groups was compared by independent sample t-test, and different brain regions were used as seeds to analyze the differences between them with the whole brain. Results: Compared with HC group, MCI group had higher VMHC value of bilateral superior temporal gyrus (41 differences voxels,t=4.264, P<0.05). The functional connectivity between left superior temporal gyrus and right fusiform gyrus,left middle frontal gyrus and right middle frontal gyrus were increased in MCI group (P<0.05), and functional connectivity between right superior temporal gyrus and left fusiform gyrus, left middle temporal gyrus, right inferior frontal gyrus, left cuneiform lobe and left middle occipital gyrus were increased (P<0.05). Conclusion:The homotopic connectivity of bilateral superior temporal gyrus was increased in patients with MCI at rest,which suggested impairment of sensory language center and compensatory enhancement of contralateral centersin MCI.