药物难治性癫痫MRI表现与脑电图及病理对照研究

Comparative Study among MRI, EEG and Pathological Findings in Medically Intractable Epilepsy

目的探讨药物难治性癫痫发作间期MRI与脑电图(EEG)在致痫灶定位中的相关性以及MRI表现的病理学基础。方法对40例药物难治性癫痫患者术前行传统MRI及视频EEG检查,并对其中25例颞叶癫痫患者行弥散加权像扫描。手术方式包括标准颞前叶切除术、选择性海马杏仁核切除术及致痫灶切除术等,对切除的脑组织进行病理学检查。结果 33例患者传统MRI检查结果显示的异常包括:海马硬化(16例)、脑发育不良(5例)、颞极蛛网膜囊肿(3例)、颅内肿瘤(3例)、脑软化灶(2例)、脉络膜裂囊肿(2例)、脑软化合并颞极蛛网膜囊肿(1例)和小脑萎缩(1例)。发作间期颞叶癫痫患者发作侧海马表观弥散系数(apparent diffusion coefficient,ADC)值[(102.1±4.7)×10^(-5) cm^2/s]较对侧[(84.6±5.9)×10^(-5) cm^2/s]明显升高(t=12.7,P<0.01)。所有癫痫患者发作间期EEG均呈异常改变。24例患者传统MRI检查所示病变区与发作间期EEG定位的致痫灶部位一致,4例患者传统MRI检查显示正常而其发作侧海马ADC值却较对侧增高。结论传统MRI与ADC同时用于评价致痫灶优于任一单独应用者,如结合EEG将更有助于对癫痫的术前评价。

Objective To explore the correlation of interictal brain MRI and electroencephalogram （EEG） in localizing the epileptogenic focus and the pathology of manifestation on MRI of medically intractable epilepsy. Methods Conventional MRI and video EEG were performed in 40 patients with intractable epilepsy considered for surgery. Twenty-five of them were also examined with diffusion weighted imaging. The surgical methods included standard anterior temporal lobectomy, selective amygdalohippocampectomy and epileptogenic focus resection. And the pathologic examination was done postoperatively. Results Thirty-three patients presented abnormal on conventional MRI. The abnormalities included hippocampal sclerosis （n= 16）, malformations of cerebral development （n = 5）, arachnoid cyst （n = 3）, brain tumor （n = 3 ）, encephalomalacia （n = 2）, choroid cyst （n=2）, encephalomalacia combined with arachnoid cyst （n = 1）, and cerebella atrophy （n = 1）. Interictal apparent diffusion coefficient （ADC） value of the ictogenic hippocampus was significantly elevated comparing with the nonictogenic hippocampus [（102.1±4.7）×10^-5 vs. （84.6±5.9）× 10 ^5 cm^2/s, t= 12.7, P〈0.01] in the patients with temporal lobe epilepsy. All the patients presented abnormal interictal EEG changes. Among these patients who presented abnormal conventional MRI, twent-four patients presented abnormal conventional MRI changes at the same location of EEG. Four patients showed normal conventional MRI and significantly elevated ADC in the hippocampus of the ictogenic side. Conclusions MRI combined with ADC was better than either technique alone. Concordance with EEG was better when MRI and ADC were jointly evaluated before epilepsy surgery.