基于弥散张量成像分析非病灶性颞叶癫痫患者脑白质网络结构变化与其执行功能障碍的关系

Analysis of relationships of white matter network structure and executive dysfunction in patients with non-focal temporal lobe epilepsy based on diffusion tensor imaging

目的基于弥散张量成像(DTI)评估非病灶性颞叶癫痫(nl-TLE)患者脑白质网络结构变化,分析其与患者执行功能障碍的关系。方法比较40例nl-TLE患者(nl-TLE组)与43名健康志愿者(对照组)的神经心理学测试评分和执行功能特征;基于DTI分析组间脑白质体积存在显著差异脑区的分布,对比脑白质纤维束各向异性分数(FA)和平均扩散率(MD);以Pearson相关分析观察nl-TLE患者脑白质体积及脑白质纤维束FA、MD值与其执行功能特征的相关性。结果nl-TLE组蒙特利尔认知评估(MOCA)、波士顿命名测试(BNT)、雷伊听觉语言学习测试(RAVLT)即刻记忆及延迟回忆评分均低于对照组;其数字广度顺向、词语流畅性低于对照组,Stroop C、朝向一致目标RT、双朝向目标RT、执行网络效率值均高于对照组(P均<0.01)。nl-TLE组左(L)-海马、右(R)-颞上回、R-楔前叶、R-后扣带回脑白质体积均小于对照组(P均<0.001);R-下纵束、L-扣带回、L-穹隆脑白质纤维束FA值较对照组降低,L-额枕下束、R-穹隆的脑白质纤维束MD值较对照组增加(P均<0.05)。nl-TLE患者上述脑区脑白质体积及脑白质纤维束FA值、MD值分别与数字广度顺向、词语流畅性、Stroop C、朝向一致目标RT、双朝向目标RT及执行网络效率值存在相关性(P均<0.05)。结论DTI可用于评估nl-TLE患者脑白质网络结构;脑白质网络结构改变与患者执行功能障碍有关。

Objective To explore the changes of white matter network structure in non-focal temporal lobe epilepsy(nl-TLE) based on diffusion tensor imaging(DTI), and to analyze the relationship between the structural changes of white matter network and executive dysfunction. Methods The scores of neuropsychological tests and executive functional characteristics of 40 patients with nl-TLE(nl-TLE group) were compared with those of 43 healthy volunteers(control group). DTI was obtained to observe the distribution of brain regions with white matter volume in nl-TLE group being different with those of control group, while white matter fractional anisotropy(FA) and the mean diffusivity(MD) were compared between groups. Pearson test was used to analyze the correlations of the changes of white matter volume, FA and MD values of white matter fiber tracts and executive function in patients with nl-TLE. Results Scores of Montreal cognitive assessment(MOCA), Boston naming test(BNT), Rey auditory verbal learning test(RAVLT) immediate memory and delayed recall of nl-TLE group were all lower than those of control group, while digit span orientation and word fluency of nl-TLE group were all lower than those in control group, Stroop C, reaction time(RT) towards consistent goal, RT toward the double direction, the efficiency of the executive network were all higher than those in control group(all P<0.01). The white matter volume of left(L)-hippocampus, right(R)-superior temporal gyrus, R-anterior wedge lobe and R-posterior cingulate gyrus in nl-TLE group were lower than those in control group(all P<0.001), while FA value of white matter fiber bundle of R-lower longitudinal bundle, L-cingulate gyrus and L-fornix were lower, MD value of the white matter fiber bundle of the L-frontal suboccipital tract and R-fornix were higher than those in control group(all P<0.05). In nl-TLE patients, white matter volume, FA and MD values of white matter fiber tracts of different brain regions were correlated with digit span orientation and word fluency, Stroop C, RT towards consistent goal, RT toward the double direction, also the efficiency of the executive network(all P<0.05). Conclusion DTI could be used to assess the structural changes of white matter network in nl-TLE patients, which were associated with executive dysfunction.