Intracranial electroencephalography study in epileptic patients with dual pathology

• Published in: Chinese medical journal 2013-07, Vol.126 (13), p.2577-2579
• Main Authors: Shi, Yan-fang, Zhang, Yu-qi, Zhou, Wen-jing, Sun, Zhao-hui, Zuo, Huan-cong
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Child; Child, Preschool; Electroencephalography; Epilepsy - pathology; Epilepsy - physiopathology; Female; Hippocampus - pathology; Humans; Male; MRI; 患者; 病变部位; 病理学观察; 癫痫; 磁共振成像; 脑电图; 评估方法
• ISSN: 0366-6999; 2542-5641
• DOI: 10.3760/cma.j.issn.0366-6999.20130645

Acommon dual pathology observed on presurgical magnetic resonance imaging （MRI） of epilepticpatients is extrahippocampal lesions combined with mesial temporal sclerosis. The hippocampus was highly vulnerable to many types of insults. However, it is difficult to detect subtle hippocampal atrophy in some patients. The most reliable method to confirm epileptogenicity is chronic intracranial electroencephalography （EEG） monitoring. In this study, we recorded intracranial EEG signals in 11 patients with dual pathology.METHODS Patient enrollment We evaluated ! 1 patients with a confirmed diagnosis of dual pathology in Yuquan Hospital, China between 2007 and 2010. The patients were satisfied with the following criteria： （1） MRI showed structural lesions in the extrahippocampal lobe; （2） a postoperative follow-up period lasting at least 24 months. For all 11 patients, both seizure frequency and impact on quality of life were judged as severe enough to justify presurgical evaluation using implanted electrodes. Detailed histories of prenatal, neonatal, and early childhood events were systematically reviewed through direct interviews with the patients. Patients were initially evaluated with noninvasive methods, including scalp EEG monitoring to capture spontaneous seizures and MRI. MRI was performed using a 1.5 T scanner and included axial images parallel to the long axis of the hippocampus. Ipsilateral and contralateral hippocampal images were visually compared to confirm mesial temporal sclerosis （MTS）. EEG recording and analysis Noninvasive data （scalp EEG and MRI） identified the mesial temporal region and a neocortical lesion site as the most likely ictal onset zones. Thus, all 11 patients were examined by implanted intracranial electrodes. To investigate the mesial temporal region, we used a stereo- eletroencephalography procedure. Depth electrodes were orthogonally directed through the middle temporal gyrus with the deepest contacts in the amygdala and anterior hippocampus. The number of neocortical electrodes implanted varied depending on the target region. Electrode positions were confirmed by post-implantation neuroimaging.