Abstract：
BACKGROUND: Hippocampal sclerosis (HS) is a prevalent cause of temporal lobe epilepsy (TLE). However, up to 30% of individuals with TLE present negative magnetic resonance imaging (MRI) findings. A comprehensive grasp of the similarities and differences in brain activity among distinct TLE subtypes holds significant clinical and scientific importance.
OBJECTIVE: To comprehensively examine the similarities and differences between TLE with HS (TLE-HS) and MRI-negative TLE (TLE-N) regarding static and dynamic abnormalities in spontaneous brain activity (SBA). Furthermore, we aimed to determine whether these alterations correlate with epilepsy duration and cognition, and to determine a potential differential diagnostic index for clinical utility.
METHODS: We measured 12 SBA metrics in 38 patients with TLE-HS, 51 with TLE-N, and 53 healthy volunteers. Voxel-wise analysis of variance (ANOVA) and post-hoc comparisons were employed to compare these metrics. The six static metrics included amplitude of low-frequency fluctuations (ALFF), fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), voxel-mirrored homotopic connectivity (VMHC), degree centrality (DC), and global signal correlation (GSCorr). Additionally, six corresponding dynamic metrics were assessed: dynamic ALFF (dALFF), dynamic fALFF (dfALFF), dynamic ReHo (dReHo), dynamic DC (dDC), dynamic VMHC (dVMHC), and dynamic GSCorr (dGSCorr). Receiver operating characteristic (ROC) curve analysis of abnormal indices was employed. Spearman correlation analyses were also conducted to examine the relationship between the abnormal indices, epilepsy duration and cognition scores.
RESULTS: Both TLE-HS and TLE-N presented as extensive neural network disorders, sharing similar patterns of SBA alterations. The regions with increased fALFF, dALFF, and dfALFF levels were predominantly observed in the mesial temporal lobe, thalamus, basal ganglia, pons, and cerebellum, forming a previously proposed mesial temporal epilepsy network. Conversely, decreased SBA metrics (fALFF, ReHo, dReHo, DC, GSCorr, and VMHC) consistently appeared in the lateral temporal lobe ipsilateral to the epileptic foci. Notably, SBA alterations were more obvious in patients with TLE-HS than in those with TLE-N. Additionally, patients with TLE-HS exhibited reduced VMHC in both mesial and lateral temporal lobes compared with patients with TLE-N, with the hippocampus displaying moderate discriminatory power (AUC = 0.759). Correlation analysis suggested that alterations in SBA indicators may be associated with epilepsy duration and cognitive scores.
CONCLUSIONS: The simultaneous use of static and dynamic SBA metrics provides evidence supporting the characterisation of both TLE-HS and TLE-N as complex network diseases, facilitating the exploration of mechanisms underlying epileptic activity and cognitive impairment. Overall, SBA abnormality patterns were generally similar between the TLE-HS and TLE-N groups, encompassing networks related to TLE and auditory and occipital visual functions. These changes were more pronounced in the TLE-HS group, particularly within the mesial and lateral temporal lobes.
OBJECTIVE: To comprehensively examine the similarities and differences between TLE with HS (TLE-HS) and MRI-negative TLE (TLE-N) regarding static and dynamic abnormalities in spontaneous brain activity (SBA). Furthermore, we aimed to determine whether these alterations correlate with epilepsy duration and cognition, and to determine a potential differential diagnostic index for clinical utility.
METHODS: We measured 12 SBA metrics in 38 patients with TLE-HS, 51 with TLE-N, and 53 healthy volunteers. Voxel-wise analysis of variance (ANOVA) and post-hoc comparisons were employed to compare these metrics. The six static metrics included amplitude of low-frequency fluctuations (ALFF), fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), voxel-mirrored homotopic connectivity (VMHC), degree centrality (DC), and global signal correlation (GSCorr). Additionally, six corresponding dynamic metrics were assessed: dynamic ALFF (dALFF), dynamic fALFF (dfALFF), dynamic ReHo (dReHo), dynamic DC (dDC), dynamic VMHC (dVMHC), and dynamic GSCorr (dGSCorr). Receiver operating characteristic (ROC) curve analysis of abnormal indices was employed. Spearman correlation analyses were also conducted to examine the relationship between the abnormal indices, epilepsy duration and cognition scores.
RESULTS: Both TLE-HS and TLE-N presented as extensive neural network disorders, sharing similar patterns of SBA alterations. The regions with increased fALFF, dALFF, and dfALFF levels were predominantly observed in the mesial temporal lobe, thalamus, basal ganglia, pons, and cerebellum, forming a previously proposed mesial temporal epilepsy network. Conversely, decreased SBA metrics (fALFF, ReHo, dReHo, DC, GSCorr, and VMHC) consistently appeared in the lateral temporal lobe ipsilateral to the epileptic foci. Notably, SBA alterations were more obvious in patients with TLE-HS than in those with TLE-N. Additionally, patients with TLE-HS exhibited reduced VMHC in both mesial and lateral temporal lobes compared with patients with TLE-N, with the hippocampus displaying moderate discriminatory power (AUC = 0.759). Correlation analysis suggested that alterations in SBA indicators may be associated with epilepsy duration and cognitive scores.
CONCLUSIONS: The simultaneous use of static and dynamic SBA metrics provides evidence supporting the characterisation of both TLE-HS and TLE-N as complex network diseases, facilitating the exploration of mechanisms underlying epileptic activity and cognitive impairment. Overall, SBA abnormality patterns were generally similar between the TLE-HS and TLE-N groups, encompassing networks related to TLE and auditory and occipital visual functions. These changes were more pronounced in the TLE-HS group, particularly within the mesial and lateral temporal lobes.
摘要：
背景：海马硬化（HS）是颞叶癫痫（TLE）的主要原因。然而,高达30%的TLE患者出现磁共振成像(MRI)阴性结果.全面掌握不同TLE亚型之间大脑活动的异同具有重要的临床和科学意义。
目的：全面研究TLE合并HS（TLE-HS）和MRI阴性TLE（TLE-N）在自发性脑活动（SBA）的静态和动态异常方面的异同。此外，我们的目的是确定这些改变是否与癫痫持续时间和认知相关，并确定临床应用的潜在鉴别诊断指标。
方法：我们测量了38例TLE-HS患者的12个SBA指标，51与TLE-N，53名健康志愿者采用体素方差分析(ANOVA)和事后比较来比较这些指标。六个静态指标包括低频波动幅度(ALFF)，低频波动的分数振幅(fALFF)，区域同质性(ReHo)，体素镜像同位连通性(VMHC)，度中心性(DC)，和全局信号相关性(GSCorr)。此外,评估了六个相应的动态指标：动态ALFF(DALFF)，动态fALFF(dfALFF),动态ReHo(dReHo),动态直流(DDC),动态VMHC(dVMHC)，和动态GSCorr(dGSCorr)。采用异常指标的受试者工作特征（ROC）曲线分析。还进行了Spearman相关分析，以检查异常指标之间的关系，癫痫持续时间和认知评分。
结果：TLE-HS和TLE-N都表现为广泛的神经网络障碍，共享类似的SBA变更模式。fALFF增加的地区，dALFF,dfALFF水平主要在颞叶内侧观察到，丘脑,基底神经节,pons,还有小脑,形成先前提出的内侧颞叶癫痫网络。相反，SBA指标下降(FALFF，ReHo,dReHo,DC,GSCorr,和VMHC）始终出现在癫痫灶同侧的颞叶外侧。值得注意的是,TLE-HS患者的SBA改变比TLE-N患者更明显。此外,与TLE-N患者相比，TLE-HS患者在内侧和外侧颞叶中的VMHC均降低，海马表现出中等的辨别力（AUC=0.759）。相关分析表明，SBA指标的改变可能与癫痫持续时间和认知评分有关。
结论：同时使用静态和动态SBA指标提供了证据，支持将TLE-HS和TLE-N表征为复杂的网络疾病，促进探索癫痫活动和认知障碍的潜在机制。总的来说,TLE-HS组和TLE-N组之间的SBA异常模式大致相似，包括与TLE和听觉和枕骨视觉功能相关的网络。这些变化在TLE-HS组中更为明显，特别是在内侧和外侧颞叶内。
目的：全面研究TLE合并HS（TLE-HS）和MRI阴性TLE（TLE-N）在自发性脑活动（SBA）的静态和动态异常方面的异同。此外，我们的目的是确定这些改变是否与癫痫持续时间和认知相关，并确定临床应用的潜在鉴别诊断指标。
方法：我们测量了38例TLE-HS患者的12个SBA指标，51与TLE-N，53名健康志愿者采用体素方差分析(ANOVA)和事后比较来比较这些指标。六个静态指标包括低频波动幅度(ALFF)，低频波动的分数振幅(fALFF)，区域同质性(ReHo)，体素镜像同位连通性(VMHC)，度中心性(DC)，和全局信号相关性(GSCorr)。此外,评估了六个相应的动态指标：动态ALFF(DALFF)，动态fALFF(dfALFF),动态ReHo(dReHo),动态直流(DDC),动态VMHC(dVMHC)，和动态GSCorr(dGSCorr)。采用异常指标的受试者工作特征（ROC）曲线分析。还进行了Spearman相关分析，以检查异常指标之间的关系，癫痫持续时间和认知评分。
结果：TLE-HS和TLE-N都表现为广泛的神经网络障碍，共享类似的SBA变更模式。fALFF增加的地区，dALFF,dfALFF水平主要在颞叶内侧观察到，丘脑,基底神经节,pons,还有小脑,形成先前提出的内侧颞叶癫痫网络。相反，SBA指标下降(FALFF，ReHo,dReHo,DC,GSCorr,和VMHC）始终出现在癫痫灶同侧的颞叶外侧。值得注意的是,TLE-HS患者的SBA改变比TLE-N患者更明显。此外,与TLE-N患者相比，TLE-HS患者在内侧和外侧颞叶中的VMHC均降低，海马表现出中等的辨别力（AUC=0.759）。相关分析表明，SBA指标的改变可能与癫痫持续时间和认知评分有关。
结论：同时使用静态和动态SBA指标提供了证据，支持将TLE-HS和TLE-N表征为复杂的网络疾病，促进探索癫痫活动和认知障碍的潜在机制。总的来说,TLE-HS组和TLE-N组之间的SBA异常模式大致相似，包括与TLE和听觉和枕骨视觉功能相关的网络。这些变化在TLE-HS组中更为明显，特别是在内侧和外侧颞叶内。
