Merlet I, Garcia-Larrea L, Grégoire M C, Lavenne F, Mauguière F
Claude Bernard University Lyon I, Department of Functional Neurology and Epileptology, France.
Brain. 1996 Apr;119 ( Pt 2):377-92. doi: 10.1093/brain/119.2.377.
Source localization methods were applied to interictal spikes from scalp EEGs and correlated with metabolic (PET scan) data in eight patients suffering from drug-resistant temporal lobe epilepsy (TLE). Dipolar sources, [18F]fluorodeoxyglucose (18FDG)-PET data and anatomical images (MRI) were projected into the same three-dimensional coordinates system. Averaged spikes were adequately modelled by two or three dipolar sources with different onset time of activation but overlapping activity (mean residual variance 3.4 +/- 2.1%). Although, in all patients, spike modelling demonstrated dipolar sources in both mesial and lateral temporal cortex, dipole propagation was consistent with the early involvement of only one of these two areas (mesio-temporal, five patients; lateral and polar neocortex, three patients). Six patients showed a unilateral interictal decrease in glucose uptake, as measured with 18FDG-PET, in the temporal lobe ipsilateral to the EEG spike focus. Temporal hypometabolism was bilateral in one patient and absent in the remaining case. When projected onto PET-scan slices, the dipolar sources of these patients were always included within the hypometabolic area. However, within the hypometabolic zone, the decrease in glucose uptake was not found to be more pronounced in regions containing dipoles. Therefore the spatio-temporal spread of neuronal hyperactivity underlying interictal spiking suggests the presence of preferential epileptogenic networks inside the hypometabolic temporal lobe. Fusion of bioelectric, metabolic and anatomical data proves to be a convenient way of summarizing multimodal information from non-invasive investigations in TLE patients entering an epilepsy surgery programme, and suggests that both interictal spike dipole modelling and 18FDG-PET data might be useful, as a complement to ictal electro-clinical data, in the presurgical evaluation of such patients.
将源定位方法应用于8例耐药性颞叶癫痫（TLE）患者头皮脑电图的发作间期棘波，并与代谢（PET扫描）数据进行关联。偶极子源、[18F]氟脱氧葡萄糖（18FDG）-PET数据和解剖图像（MRI）被投影到同一个三维坐标系中。平均棘波可由两个或三个偶极子源进行充分建模，这些偶极子源具有不同的激活起始时间但活动重叠（平均剩余方差3.4 +/- 2.1%）。尽管在所有患者中，棘波建模均显示在颞叶内侧和外侧皮质均存在偶极子源，但偶极子传播仅与这两个区域之一（颞叶内侧，5例患者；外侧和极新皮质，3例患者）的早期受累一致。6例患者经18FDG-PET测量显示，脑电图棘波灶同侧颞叶的发作间期葡萄糖摄取单侧减少。1例患者颞叶低代谢为双侧性，其余病例未发现低代谢。当投影到PET扫描切片上时，这些患者的偶极子源总是包含在低代谢区域内。然而，在低代谢区内，未发现偶极子所在区域的葡萄糖摄取减少更为明显。因此，发作间期棘波背后神经元活动过度的时空传播提示在低代谢的颞叶内存在优先的致痫网络。生物电、代谢和解剖数据的融合被证明是一种方便的方式，可总结来自进入癫痫手术程序的TLE患者非侵入性检查的多模态信息，并表明发作间期棘波偶极子建模和18FDG-PET数据作为发作期电临床数据的补充，在这类患者的术前评估中可能有用。
