Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
Hum Brain Mapp. 2023 Feb 1;44(2):549-558. doi: 10.1002/hbm.26083. Epub 2022 Sep 29.
Temporal lobe epilepsy (TLE) is one of the most common subtypes of focal epilepsy, with mesial temporal sclerosis (MTS) being a common radiological and histopathological finding. Accurate identification of MTS during presurgical evaluation confers an increased chance of good surgical outcome. Here we propose the use of glutamate-weighted chemical exchange saturation transfer (GluCEST) magnetic resonance imaging (MRI) at 7 Tesla for mapping hippocampal glutamate distribution in epilepsy, allowing to differentiate lesional from non-lesional mesial TLE. We demonstrate that a directional asymmetry index, which quantifies the relative difference between GluCEST contrast in hippocampi ipsilateral and contralateral to the seizure onset zone, can differentiate between sclerotic and non-sclerotic hippocampi, even in instances where traditional presurgical MRI assessments did not provide evidence of sclerosis. Overall, our results suggest that hippocampal glutamate mapping through GluCEST imaging is a valuable addition to the presurgical epilepsy evaluation toolbox.
颞叶癫痫（TLE）是最常见的局灶性癫痫亚型之一，其中内侧颞叶硬化（MTS）是常见的影像学和组织病理学发现。在术前评估中准确识别 MTS 可以增加手术结果良好的机会。在这里，我们建议在 7 特斯拉场强下使用谷氨酸加权化学交换饱和传递（GluCEST）磁共振成像（MRI）来绘制癫痫中海马谷氨酸的分布，从而区分病变侧和非病变侧的内侧 TLE。我们证明，一个方向不对称指数可以量化起源于癫痫发作区同侧和对侧海马之间的 GluCEST 对比的相对差异，即使在传统的术前 MRI 评估没有提供硬化证据的情况下，也可以区分硬化和非硬化的海马。总的来说，我们的结果表明，通过 GluCEST 成像进行海马谷氨酸映射是术前癫痫评估工具包的一个有价值的补充。
