MRI和CT阴性表现的脑致痫灶定位研究

目的回顾性分析难治性癫痫手术治疗的临床资料,探讨MRI和CT阴性表现病例的致痫灶定位方法.方法经MRI和CT检查呈阴性表现的癫痫患者42例,应用发作症状评估、长程头皮和颅内电极视频脑电图（video-EEG）监测等方法综合定位致痫灶.结果36例（85.7%）患者可以明确定位致痫灶,其中位于颞叶19例,额叶12例,额叶＋颞叶3例,顶枕叶2例;多灶性起源或定位不明确者6例,2例放弃手术.40例脑致痫灶组织均有不同程度的病理改变.结论一些局灶性皮质发育不良、微发育不良等细微脑组织改变通过现有的MRI和CT影像学检查尚难以发现,而它们常常是导致癫痫发作的病理基础.综合分析患者的临床发作特点,特别是长程EEG监测资料,可为大部分的此类病例明确定位脑致痫灶.

A study on localization of epileptogenic zones in refractory epilepsy patients with non-lesional MRI and CT findings

Objective To explore strategy on localization of epileptogenic zone in refractory epilepsy patients with non-lesional MRI and CT findings. Methods Forty-two patients were retrospectively studied. The symptomatic analysis, SPECT examination, long term video-EEG monitoring and in some cases chronic intracranial recording were comprehensively applied to localize epileptogenic zones. Results Localization of epileptogenic zones was accomplished in 7 patients by noninvasive methods and chronic intracranial electrical recordings were further employed in other 35 patients. The epileptogenic zones, localized in 36 patients (85. 7% ) with comprehensively use of these methods were in temporal lobe in 19 patients, frontal lobe in 12, temporal and frontal lobes in 3, occipital-parietal lobes in 2. Multiple foci existed, or localization was not confirmed in other 6 patients. Pathologic findings revealed mesial temporal sclerosis ( n=5 ), gliosis (n = 6) , heterotopic gray matter ( n = 4 ), chronic cephalitis ( n = 2 ), focal cortical dysplasia or microdysgenesis (n= 18) and others (n =5). Conclusions The localization of epileptogenic zones in those patients relied on comprehensive evaluation and examinations. The symptomatic analysis, SPECT examination, long term video-EEG and particularly chronic intracranial EEG recording in most cases contribute a definite localization of the epileptogenic zones. The pathologic changes, such as cortical dysplasia, cerebral microdysgenesis and so on, is the basis of those refractory seizures, which can not be found with current neuroimaging techniques.