Yildirim Mehmet S, Stepponat Radheshyam, Fischmeister Florian Ph S, Tomschik Matthias, Schmidbauer Victor, Khalaveh Farjad, Koren Johannes, Baumgartner Christoph, Pataraia Ekaterina, Bonelli Silvia, Rössler Karl, Kasprian Gregor, Dorfer Christian
Department of Neurosurgery, Medical University of Vienna, Vienna, Austria.
Developmental and Interventional Neuroimaging Lab (DINLAB), Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
Eur J Neurol. 2025 Jan;32(1):e70040. doi: 10.1111/ene.70040.
Temporal lobe epilepsy (TLE) can lead to structural brain abnormalities, with thalamus atrophy being the most common extratemporal alteration. This study used probabilistic tractography to investigate the structural connectivity between individual thalamic nuclei and the hippocampus in TLE.
Thirty-six TLE patients who underwent pre-surgical 3 Tesla magnetic resonance imaging (MRI) and 18 healthy controls were enrolled in this study. Patients were subdivided into TLE with HS (TLE-HS) and MRI-negative TLE (TLE-MRneg). Tractography and whole brain segmentation, including thalamus parcellation, were performed to determine the number of streamlines per mm between the thalamic nuclei and hippocampus. Connectivity strength and volume of regions were correlated with clinical data.
The volume of the entire thalamus ipsilateral to seizure onset was significantly decreased in TLE-HS compared to controls (Mann-Whitney-U test: p < 0.01) with the anterior thalamic nuclei (ANT) as important contributor. Furthermore, decreased ipsilateral connectivity strength between the hippocampus and ANT was detected in TLE-HS (p < 0.01) compared to TLE-MRneg and controls which correlated negatively with the duration of epilepsy (ρ = -0.512, p = 0.025) and positively with seizure frequency (ρ = 0.603, p = 0.006). Moreover, ANT volume correlated negatively with epilepsy duration in TLE-HS (ρ = -0.471, p = 0.042).
ANT showed atrophy and decreased connectivity in TLE-HS, which correlated with epilepsy duration and seizure frequency. Understanding the dynamics of epileptogenic networks has the potential to shed light on surgery-resistant epilepsy and refine the selection process for ideal neurosurgical candidates, consequently enhancing post-surgical outcomes.
颞叶癫痫（TLE）可导致脑结构异常，丘脑萎缩是最常见的颞外改变。本研究采用概率性纤维束成像技术，研究TLE患者个体丘脑核与海马之间的结构连接性。
本研究纳入了36例接受术前3特斯拉磁共振成像（MRI）检查的TLE患者和18名健康对照者。患者被分为伴有海马硬化的TLE（TLE-HS）和MRI阴性的TLE（TLE-MRneg）。进行纤维束成像和全脑分割，包括丘脑分割，以确定丘脑核与海马之间每毫米的纤维束数量。区域的连接强度和体积与临床数据相关。
与对照组相比，TLE-HS患者癫痫发作起始侧整个丘脑的体积显著减小（曼-惠特尼U检验：p < 0.01），丘脑前核（ANT）是重要的影响因素。此外，与TLE-MRneg和对照组相比，TLE-HS患者海马与ANT之间同侧连接强度降低（p < 0.01），这与癫痫持续时间呈负相关（ρ = -0.512，p = 0.025），与癫痫发作频率呈正相关（ρ = 0.603，p = 0.006）。此外，TLE-HS患者的ANT体积与癫痫持续时间呈负相关（ρ = -0.471，p = 0.042）。
在TLE-HS患者中，ANT出现萎缩且连接性降低，这与癫痫持续时间和发作频率相关。了解致痫网络的动态变化有可能为难治性癫痫提供线索，并优化理想神经外科手术候选者的选择过程，从而提高术后疗效。
