INSERM UMR 1106, Institut de Neurosciences des Systèmes, Marseille, France; Faculty of Medicine, Aix-Marseille University, Marseille, France.
Epilepsia. 2014 Feb;55(2):264-77. doi: 10.1111/epi.12490. Epub 2013 Dec 24.
Frontal lobe seizures are difficult to characterize according to semiologic and electrical features. We wished to establish whether different semiologic subgroups can be identified and whether these relate to anatomic organization.
We assessed all seizures from 54 patients with frontal lobe epilepsy that were explored with stereoelectroencephalography (SEEG) during presurgical evaluation. Semiologic features and concomitant intracerebral EEG changes were documented and quantified. These variables were examined using Principal Component Analysis and Cluster Analysis, and semiologic features correlated with anatomic localization.
Four main groups of patients were identified according to semiologic features, and correlated with specific patterns of anatomic seizure localization. Group 1 was characterized clinically by elementary motor signs and involved precentral and premotor regions. Group 2 was characterized by a combination of elementary motor signs and nonintegrated gestural motor behavior, and involved both premotor and prefrontal regions. Group 3 was characterized by integrated gestural motor behavior with distal stereotypies and involved anterior lateral and medial prefrontal regions. Group 4 was characterized by seizures with fearful behavior and involved the paralimbic system (ventromedial prefrontal cortex ± anterior temporal structures). The groups were organized along a rostrocaudal axis, representing bands within a spectrum rather than rigid categories. The more anterior the seizure organization, the more likely was the occurrence of integrated behavior during seizures. Distal stereotypies were associated with the most anterior prefrontal localizations, whereas proximal stereotypies occurred in more posterior prefrontal regions.
Meaningful categorization of frontal seizures in terms of semiology is possible and correlates with anatomic organization along a rostrocaudal axis, in keeping with current hypotheses of frontal lobe hierarchical organization. The proposed electroclinical categorization offers pointers as to the likely zone of organization of networks underlying semiologic production, thus aiding presurgical localization. Furthermore, analysis of ictal motor behavior in prefrontal seizures, including stereotypies, leads to deciphering the cortico-subcortical networks that produce such behaviors.
根据半侧化和电特征，额叶癫痫发作很难进行特征描述。我们希望确定是否可以识别不同的半侧化亚组，以及这些亚组是否与解剖结构有关。
我们评估了 54 例经立体脑电图（SEEG）术前评估的额叶癫痫患者的所有癫痫发作。记录和量化了半侧化特征和伴随的颅内 EEG 变化。使用主成分分析和聚类分析检查了这些变量，并且将半侧化特征与解剖定位相关联。
根据半侧化特征，我们确定了 4 组主要的患者群体，并且与特定的解剖定位发作模式相关。第 1 组临床特征为基本运动体征，涉及中央前区和运动前区。第 2 组的特征是基本运动体征与非整合的手势运动行为相结合，涉及运动前区和前额叶区域。第 3 组的特征是具有远端刻板动作的整合手势运动行为，涉及前外侧和内侧前额叶区域。第 4 组的特征是伴有恐惧行为的癫痫发作，涉及边缘系统（腹内侧前额叶皮质±前颞叶结构）。这些组沿着前后轴组织，代表谱带内的带，而不是僵硬的类别。发作组织越靠前，发作期间发生整合行为的可能性就越大。远端刻板动作与最靠前的前额叶定位相关，而近端刻板动作发生在更靠后的前额叶区域。
从半侧化的角度对额叶癫痫进行有意义的分类是可能的，并且与前后轴上的解剖结构组织相关，这与额叶的层级组织的当前假说一致。提出的电临床分类为半侧化产生的网络的可能组织区域提供了线索，从而有助于术前定位。此外，对额叶癫痫发作中的癫痫运动行为（包括刻板动作）进行分析，可以揭示产生这些行为的皮质-皮质下网络。
