【作者】 黄佳玲；

【导师】 罗华；

【作者基本信息】 西南医科大学 ， 神经病学（专业学位）， 2022， 硕士

【摘要】 目的:基于静息态功能磁共振成像(resting-state fMRI)的动静态局部一致性分析(Regional Homogeneity,ReHo)和大尺度功能连接分析,探讨伴有头晕/眩晕的后循环脑梗死的脑自发活动和功能连接差异。方法:纳入2021年5月至2022年1月就诊于西南医科大学第一附属医院神经内科确诊为伴有头晕/眩晕的后循环脑梗死患者27例(PCI组),再纳入与之匹配的健康中老年人27例(HC组),采集两组一般人口学统计资料,其中伴有头晕/眩晕的后循环脑梗死患者完善DHI、HADS等量表评分。两组分别进行磁共振结构像T1和功能像EPI序列的扫描,得到的fMRI图像数据预处理后进行脑网络分析,采用动静态ReHo分析比较PCI组和HC组大脑自发活动下的差异脑区,采用大尺度功能连接分析比较两组脑网络连接差异,再将脑网络与量表评分做相关性分析。将PCI组分为头晕组和眩晕组两个亚组,比较两组大尺度功能连接网络内和网络间的差异,根据实际情况,将PCI组分为小脑梗死组和其他部位组,采用大尺度功能连接分析比较两组脑网络的差异。结果:1.静态ReHo分析结果比较:PCI组和HC组的差异脑区为右侧海马,右侧颞上回,左侧中扣带回,左侧额叶中回,双侧中央前回,右侧中央后回,右侧缘上回和右侧脑岛。2.动态ReHo分析结果比较:两组的动态ReHo差异脑区为右侧颞上回,右侧颞中回,右侧海马,左侧中扣带回,左侧补充运动区,双侧小脑crus9区。动静态ReHo的共同差异脑区为右侧海马,右侧颞上回和左侧中扣带回。3.大尺度功能连接分析结果比较:与HC组相比,PCI组在视觉网络,皮层下网络,背侧注意网络,听觉网络,带状盖网络和感觉躯体运动网络的网络内功能连接均下降(FDR P<0.05),其中听觉网络,带状盖网络和感觉躯体运动网络的网络内功能连接明显下降(FDR P<0.01)。与HC组相比,PCI组网络间连接差异主要集中在背侧注意网络,带状盖网络、视觉网络和感觉躯体运动网络。PCI组的背侧注意网络与带状盖网络、视觉网络、额顶区控制网络的功能连接降低(FDR P<0.05),视觉网络与默认模式网络、感觉躯体网络间的功能连接下降(FDR P<0.05),腹侧注意网络与小脑网络,带状盖网络与额顶区控制网络、感觉躯体运动网络的功能连接均降低(FDR P<0.05)。其中,感觉躯体与视觉网络的功能连接显著下降(FDR P<0.01),带状盖网络与背侧注意网络、额顶区控制网络、感觉躯体运动网络的功能连接均显著下降(FDR P<0.01)。4.大尺度功能连接与量表评分的相关性分析:PCI组背侧注意网络和视觉网络与HADS评分之间呈负相关,背侧注意网络与DHI评分之间呈负相关。5.将PCI组分为头晕组和眩晕组,发现头晕组在默认网络和额顶区控制网络,腹侧注意网络和小脑网络的之间的平均功能连接下降(p<0.05)。两亚组在皮层下网络内平均功能连接存在显著差异(p<0.01),在小脑网络内的平均功能连接上存在差异(p<0.05)。将PCI组分为小脑梗死组和其他部位组,发现小脑梗死组和其他部位梗死组默认模式网络到视觉网络的网络间平均功能连接存在显著差异(P<0.05),其余网络间连接未见明显差异,两个亚组的大尺度功能连接网络内未见明显差异。结论:1.本研究基于rs-fMRI对伴有头晕/眩晕的后循环脑梗死组和健康老年人组进行动静态的ReHo分析,发现两组被试动静态ReHo分析共同的差异脑区在右侧海马,右侧颞上回和左侧中扣带回,表明伴有头晕/眩晕的后循环梗死患者存在颞叶、海马区域活动的异常改变,这种改变可能与损伤部位累及到前庭皮层网络相关。2.发现大尺度功能连接网络异常的改变主要是在躯体感觉网络、视觉网络和背侧注意网络,推测可能与代偿性的多感觉皮层间的交互抑制相关。3.大尺度功能连接的背侧注意网络与HADS评分呈负相关,患者抑郁表现可能与背侧注意网络到视觉网络的失调有关。4.对PCI亚组分析,眩晕组较头晕组大尺度功能连接网络内和网络间均增强,这种改变可能可以在一定程度上评估后循环脑梗死眩晕的严重程度,小脑梗死组较其他部位组视觉网络到默认模式网络网络间平均功能连接增强,这可能与小脑梗死更高的视觉依赖性相关。本研究应用rs-fMRI,从脑自发活动和脑网络的角度揭示了伴有头晕/眩晕的后循环脑梗死患者的病理生理变化,为疾病的研究提供新的视角。更多还原

【Abstract】 Objective:To investigate differences in spontaneous brain activity and functional connectivity in posterior circulation infarction with dizziness/vertigo based on resting-state functional magnetic resonance imaging(resting-state fMRI)with regional homogeneity(ReHo)and large scale functional connectivity analysis.Methods:Patients27 with posterior circulation cerebral infarction with dizziness/vertigo diagnosed in the Department of Neurology of the First Affiliated Hospital of Southwest Medical University(PCI group)and matched healthy middle-aged27 and elderly patients(HC group)were included2021,and general demographic statistics were collected from2022 both groups.The two groups were scanned with MRI structural image T1 and functional image EPI sequences respectively.The obtained fMRI image data were pre-processed for brain network analysis,and dynamic and static ReHo analysis was used to compare the differential brain areas under spontaneous brain activity in the PCI and HC groups,and large scale functional connectivity analysis was used to compare the differences in brain network connectivity between the two groups,and then the brain network was correlated with the scale scores.The PCI group was divided into two subgroups,the dizziness group and the vertigo group,to compare the differences within and between the networks of large-scale functional connectivity between the two groups.Depending on the actual situation,the PCI group was divided into the cerebellar infarct group and the other site group,and the differences in brain networks between the two groups were compared using large-scale functional connectivity analysis.Results::1.Comparison of the results of static ReHo analysis:the differential brain areas in the PCI and HC groups were the right hippocampus,right superior temporal gyrus,left middle cingulate gyrus,left middle frontal gyrus,bilateral precentral gyrus,right postcentral gyrus,right superior limbic gyrus and right insula.2.Comparison of the results of the dynamic ReHo analysis:the brain areas differing in dynamic ReHo between the two groups were the right superior temporal gyrus,the right middle temporal gyrus,the right hippocampus,the left middle cingulate gyrus,the left supplementary motor area,and the bilateral cerebellar crus9 area.The common differential brain areas for dynamic and static ReHo were the right hippocampus,right superior temporal gyrus and left middle cingulate gyrus.3.Comparison of results from large-scale functional connectivity analysis:compared to the HC group,the PCI group showed decreased intra-network functional connectivity in the visual network,subcortical network,dorsal attention network,auditory network,ribbon cap network and sensory somatomotor network(FDR P<0.05),with a significant decrease in intra-network functional connectivity in the auditory network,ribbon cap network and sensory somatomotor network(FDR P<0.01).Compared to the HC group,inter-network connectivity differences in the PCI group were mainly in the dorsal attention network,the ribbon cover network,the visual network and the sensory somatomotor network.functional connectivity between the dorsal attention network and the ribbon cover network,the visual network and the frontoparietal control network was reduced in the PCI group(FDR P<0.05),and functional connectivity between the visual network and the default mode network and the sensory somatomotor network was reduced(FDR P<0.05),and reduced functional connectivity between the ventral attention network and the cerebellar network,the ribbon cap network and the frontoparietal control network,and the sensory somatic motor network(FDR P<0.05).The functional connectivity of the sensory somatic and visual networks was significantly reduced(FDR P<0.01),and the functional connectivity of the ribbon cap network with the dorsal attentional network,the frontoparietal control network,and the sensory somatic motor network was significantly reduced(FDR P<0.01).4.Correlation analysis between large-scale functional connectivity and scale scores:there was a negative correlation between the dorsal attention network and visual network and HADS scores in the PCI group,and a negative correlation between the dorsal attention network and DHI scores.5.Dividing the PCI group into a dizziness group and a vertigo group,the dizziness group was found to have decreased mean functional connectivity between the default and frontoparietal control networks,the ventral attention network and the cerebellar network(p<0.05).The two subgroups differed significantly(p<0.01)in the mean functional connectivity within the subcortical network and in the mean functional connectivity within the cerebellar network(p<0.05).Dividing the PCI group into cerebellar infarct group and other sites group,it was found that there was a significant difference in the mean functional connectivity between the default pattern network to the visual network in the cerebellar infarct group and other sites infarct group(p<0.05),no significant difference was seen in the remaining inter-network connectivity,and no significant difference was seen within the large scale functional connectivity network in the two subgroups.Conclusion:1.In this study,we performed dynamic and static ReHo analysis based on rs-fMRI in the posterior circulation cerebral infarction group with dizziness/vertigo and in the healthy elderly group,and found that the common differential brain regions for dynamic and static ReHo analysis in both groups of subjects were in the right hippocampus,right superior temporal gyrus and left middle cingulate gyrus,indicating that patients with posterior circulation infarction with dizziness/vertigo have abnormal alterations in activity in temporal lobe and hippocampal regions,and that such alterations may be associated with involvement of the vestibular cortex network at the site of injury.2.Abnormal alterations in large-scale functional connectivity networks were found mainly in the somatosensory,visual and dorsal attention networks,presumably associated with compensatory multisensory cortical cross-inhibition.3.The dorsal attention network of large-scale functional connectivity was negatively correlated with HADS scores,and the patient’s depressive presentation may be related to dysregulation of the dorsal attention network to the visual network.4.For the PCI subgroup analysis,the vertigo group had enhanced large scale functional connectivity both within and between networks compared to the dizziness group,an alteration that may allow some assessment of the severity of vertigo in posterior circulation cerebral infarction,and the enhanced mean functional connectivity between the visual network to default mode network networks in the cerebellar infarction group compared to the other site groups,which may be associated with the higher visual dependence of cerebellar infarction.In this study,rs-fMRI was applied to reveal pathophysiological changes in patients with posterior circulation cerebral infarction with dizziness/vertigo from the perspective of brain spontaneous activity and brain networks,providing a new perspective for the study of the disease.更多还原