颞叶癫痫患者丘脑网络异常与认知功能的相关性

Correlation between thalamic network abnormity and cognitive function in patients with temporal lobe epilepsy

目的探究颞叶癫痫(temporal lobe epilepsy,TLE)患者丘脑网络异常与认知功能下降的相关性及其机制。方法纳入2018年12月至2020年2月在广西医科大学第一附属医院癫痫专科门诊就诊的53例单侧TLE患者,同时招募37名人口学特征相匹配的健康对照,进行蒙特利尔认知评估(Montreal cognitive assessment,MoCA)及结构、功能磁共振检查。使用基于体素的形态学测量研究单侧TLE患者的丘脑灰质体积变化,使用基于种子点的结构协变网络和功能连接网络分析研究TLE患者的丘脑网络变化,对异常的丘脑结构、丘脑网络变化与认知功能评分进行相关性分析。采用SPSS 22.0软件进行统计分析。组间比较采用独立样本t检验和Mann-Whitney U检验。为探索TLE患者的丘脑及丘脑网络与认知表现的关系,提取丘脑体积及存在异常协同性改变的脑区的灰质体积、功能连接值与MoCA评分进行相关性分析。结果TLE患者的MoCA总评分[27.0(25.0,29.0)分]低于健康对照[29.0(28.0,30.0)分](Z=-4.601,P<0.001)。全脑灰质体积分析显示,与健康对照相比,TLE患者的左侧小脑、右侧颞极、右侧梭状回、直回、双侧颞中回、丘脑、内侧和旁扣带回表现出显著的体积缩小(经GRF校正,体素水平P<0.001,团块水平P<0.05);以差异丘脑为种子点的结构协变网络分析显示,TLE患者丘脑与右侧梭状回(MNI:x=28.5,y=-15.0,z=-34.5)、左侧脑岛(MNI:x=-33.0,y=-18.0,z=-1.5)、右侧颞中回(MNI:x=55.5,y=-51.0,z=9.0)、左侧补充运动区(MNI:x=-10.5,y=1.5,z=57.0)和右侧中央后回脑区(MNI:x=31.5,y=-33.0,z=51.0)的协同性较健康对照减低(P<0.001,体素>100);以差异丘脑为种子点的功能连接网络分析显示,TLE患者丘脑与左侧脑岛(MNI:x=-38,y=-7,z=-7)、左侧舌回(MNI:x=-6,y=-81,z=-12)、右侧舌回(MNI:x=15,y=-105,z=0)和左侧三角部额下回(MNI:x=-39,y=36,z=-6)的连通性较健康对照下降(GRF校正,体素水平P<0.001,团块水平P<0.05)。在TLE患者中,与丘脑协同性减低的左侧脑岛体积与MoCA总评分呈正相关(r=0.279,P=0.043),与丘脑协同性减低的左侧补充运动区体积与MoCA总评分、语言评分呈正相关(r=0.323,P=0.018;r=0.334,P=0.015);与丘脑功能连接减弱的右侧舌区功能连接值与回忆评分呈负相关(r=-0.331,P=0.016)。结论TLE患者的丘脑体积、丘脑结构协变网络及功能连接网络均发生改变。丘脑网络的异常与TLE认知表现有关,可能是丘脑参与TLE患者认知障碍的神经机制。

Objective To explore the correlation and mechanism between thalamic network abnormality and cognitive decline in patients with temporal lobe epilepsy(TLE).Methods A total of 53 patients with unilateral TLE were consecutively enrolled through the epilepsy clinic of the First Affiliated Hospital of Guangxi Medical University from December 2018 to February 2020.During the same recruitment interval,37 health controls(HC)with matching demographic characteristic were recruited.All subjects were received the Montreal cognitive assessment(MoCA)test and multimodal MRI scanning.Voxel-based morphometry method was used to study the changes of thalamic gray matter volume in patients with unilateral TLE.The structural covariance network and functional connectivity network based on seed points were used to analyze the changes of thalamic network in TLE patients.In addition,the correlations among abnormal thalamic structure,thalamic network and cognitive function score were analyzed.SPSS 22.0 software was used for statistical analysis.Independent sample t-test and Mann Whitney U test were used for inter group comparison.In order to explore the relationship between thalamus and thalamic network and cognitive performance in TLE patients,thalamic volume and gray matter volume and functional connection value of brain areas with abnormal synergistic changes were extracted and correlated with MoCA score.Results The total score of MoCA in TLE patients(27.0(25.0,29.0))was significantly decreased compared with HC(29.0(28.0,30.0))(Z=-4.601,P<0.001).Whole brain gray matter volume analysis showed that compared with HCTLE patients showed significant volume reduction in left cerebellum,right temporal pole,right fusiform gyrus,straight gyrus,bilateral middle temporal gyrus,thalamus,medial and paracingulate gyrus(GRF adjusted,voxel-level P<0.001 and cluster-level P<0.05).The thalamus-associated structural covariance network analysis revealed that compared with healthy controls,TLE patients exhibited decreased connectivity in right fusiform gyrus(MNI:x=28.5,y=-15.0,z=-34.5),left insula(MNI:x=-33.0,y=-18.0,z=-1.5),right middle temporal gyrus(MNI:x=55.5,y=-51.0,z=9.0),left complementary motor area(MNI:x=-10.5,y=1.5,z=57.0)and right posterior central gyrus(MNI:x=31.5,y=-33.0,z=51.0)(P<0.001,cluster>100).The thalamus-associated functional connectivity network analysis revealed that TLE patients exhibited decreased connectivity in left insula(MNI:x=-38,y=-7,z=-7),left lingual gyrus(MNI:x=-6,y=-81,z=-12),right lingual gyrus(MNI:x=15,y=-105,z=0)and left triangular inferior frontal gyrus(MNI:x=-39,y=36,z=-6)(GRF correction,voxel-level P<0.001 and cluster-level P<0.05).Volume of left insula which had decreased structural connectivity with thalamus were positively correlated with the MoCA score in TLE patients(r=0.279,P=0.043).Volume of left complementary motor area which had decreased structural connectivity with thalamus was positively correalated with the MoCA score and language score in TLE patients(r=0.323,P=0.018;r=0.334,P=0.015).Volume of left lingual gyrus which had decreased functional connectivity with thalamus was negatively correalated with the memory score in TLE patients(r=-0.331,P=0.016).Conclusion Thalamic volume,thalamic structural covariant network and functional connection network are changed in TLE patients.The abnormality of thalamic network is associated with cognitive performance in TLE patients,which may be the neural mechanism of thalamus participating in the cognitive impairment of TLE patients.