目的:颞叶癫痫(TLE)具有很高的耐药性,经常被考虑进行手术干预。然而,30%的TLE病例有非病灶磁共振成像(MRI)扫描,这与较差的手术结果有关。表征这些患者的颞部和颞部结构之间的相互作用可能有助于理解这些不良结果。同时颅内脑电图功能MRI(iEEG-fMRI)可以测量与直接从大脑记录的发作间癫痫样放电(IED)相关的血液动力学变化。这项研究旨在表征IED相关fMRI激活的整个大脑模式,该模式仅记录在非病灶性TLE患者的颞叶内侧。
方法:18例非损伤性TLE患者接受iEEG监测,并在3T进行iEEG-fMRI。并确定了具有统计学意义的fMRI激活簇。确定每位患者IED相关功能磁共振成像激活的位置,根据fMRI激活的位置和模式对患者进行分组.
结果:出现了IED相关功能磁共振成像激活的两种模式:主要是局部(n=7),激活主要位于同侧颞叶内,主要是弥漫性的(n=11),检测到广泛的双侧颞外激活。主要弥漫性组报告的双侧强直阵挛性癫痫发作明显减少,术后结局更好。
结论:同时进行iEEG-fMRI可以测量与头皮EEG上不可见的局灶性IED相关的血液动力学变化,比如从颞叶内侧产生的。在所有患者中均观察到与这些IED相关的显着fMRI激活。发现了两种不同的IED相关激活模式:主要位于同侧颞叶,更广泛,双边激活。广泛的IED相关激活的患者局灶性至双侧强直阵挛性癫痫发作较少,术后结局较好。这可能表明限制发作事件传播的神经保护机制。
OBJECTIVE: Temporal lobe epilepsy (TLE) has a high probability of becoming drug resistant and is frequently considered for surgical intervention. However, 30% of TLE cases have nonlesional magnetic resonance imaging (MRI) scans, which is associated with worse surgical outcomes. Characterizing interactions between temporal and extratemporal structures in these patients may help understand these poor outcomes. Simultaneous intracranial electroencephalography-functional MRI (iEEG-fMRI) can measure the hemodynamic changes associated with interictal epileptiform discharges (IEDs) recorded directly from the brain. This study was designed to characterize the whole brain patterns of IED-associated fMRI activation recorded exclusively from the mesial temporal lobes of patients with nonlesional TLE.
METHODS: Eighteen patients with nonlesional TLE undergoing iEEG monitoring with mesial temporal IEDs underwent simultaneous iEEG-fMRI at 3 T. IEDs were marked, and statistically significant clusters of fMRI activation were identified. The locations of IED-associated fMRI activation for each patient were determined, and patients were grouped based on the location and pattern of fMRI activation.
RESULTS: Two patterns of IED-associated fMRI activation emerged: primarily localized (n = 7), where activation was primarily located within the ipsilateral temporal lobe, and primarily diffuse (n = 11), where widespread bilateral extratemporal activation was detected. The primarily diffuse group reported significantly fewer focal to bilateral tonic-clonic seizures and had better postsurgical outcomes.
CONCLUSIONS: Simultaneous iEEG-fMRI can measure the hemodynamic changes associated with focal IEDs not visible on scalp EEG, such as those arising from the mesial temporal lobe. Significant fMRI activation associated with these IEDs was observed in all patients. Two distinct patterns of IED-associated activation were seen: primarily localized to the ipsilateral temporal lobe and more widespread, bilateral activation. Patients with widespread IED associated-activation had fewer focal to bilateral tonic-clonic seizures and better postsurgical outcome, which may suggest a neuroprotective mechanism limiting the spread of ictal events.