Mazzola Laure, Mauguière François, Isnard Jean
*Department of Neurology, University Hospital of St-Etienne, France; †Team "Central Integration of Pain", Lyon Neuroscience Research Center, INSERM U 1028, CNRS UMR 5292, Lyon, France; ‡Jean Monnet University, St-Etienne, France; §Department of Functional Neurology and Epilepsy, Neurological Hospital, Hospices Civils de Lyon, Lyon, France; and ‖Claude Bernard University Lyon 1, Lyon, France.
J Clin Neurophysiol. 2017 Jul;34(4):307-314. doi: 10.1097/WNP.0000000000000382.
Stereotactic stimulations of the insular cortex through intracranial electrodes aim at characterizing the semiology of insular seizures. These stimulations, carried out in the context of Stereo-Electro-Encephalography (SEEG) during presurgical monitoring of epilepsy, reproduce the ictal symptoms observed during the development of insular seizures.
The authors reviewed the results of insular stimulations performed in 222 patients admitted between 1997 and 2015 for presurgical SEEG exploration of atypical temporal or perisylvian epilepsy. Stimulations (50 Hz, trains of 5 seconds, pulses of 0.5 ms, intensity 0.2-3.5 mA) were carried out using transopercular electrodes implanted orthogonal to midsagittal plane.
Out of a total of 669 stimulations, 550 were clinically eloquent in the absence of any postdischarge (237 and 313, respectively, in the right and left insulae). Somatosensory responses (61% of evoked sensations) including pain and visceral sensations (14.9%) were the most frequent, followed by auditory sensations (8%), vestibular illusions (7.5%), speech impairment (5%), gustatory, (2.7%), and olfactory (1%) sensations. Although these responses showed some functional segregation (in particular a privileged pain representation in the postero-superior quadrant), there was a clear spatial overlap between representations of the different modalities.
Symptoms evoked by insular stimulations are multiple. None of them can be considered as absolutely specific to the insular cortex, but the occurrence in given seizure of a somatosensory symptom such as pain or of a laryngeal spasm associated with vestibular, auditory, aphasic, or olfacto-gustatory symptoms points to a discharge development in the insular cortex, which is the only cortical region where stimulations demonstrate such a multimodal representation.
通过颅内电极对岛叶皮质进行立体定向刺激旨在明确岛叶癫痫的症状学。这些刺激在癫痫术前监测的立体定向脑电图（SEEG）过程中进行，再现了岛叶癫痫发作时观察到的发作症状。
作者回顾了1997年至2015年间因非典型颞叶或外侧裂周围癫痫接受术前SEEG检查而入院的222例患者的岛叶刺激结果。刺激（50赫兹，5秒的串，0.5毫秒的脉冲，强度0.2 - 3.5毫安）使用与正中矢状面正交植入的经手术电极进行。
在总共669次刺激中，550次在无任何放电情况下具有临床意义（右侧和左侧岛叶分别为237次和313次）。躯体感觉反应（诱发感觉的61%）包括疼痛和内脏感觉（14.9%）最为常见，其次是听觉感觉（8%）、前庭幻觉（7.5%）、言语障碍（5%）、味觉（2.7%）和嗅觉（1%）感觉。尽管这些反应显示出一些功能分离（特别是在后上象限有优先的疼痛表征），但不同模式的表征之间存在明显的空间重叠。
岛叶刺激诱发的症状多种多样。其中没有一种可被视为绝对特定于岛叶皮质，但在特定发作中出现躯体感觉症状如疼痛或与前庭、听觉、失语或嗅觉 - 味觉症状相关的喉痉挛表明岛叶皮质有放电发生，而岛叶皮质是唯一刺激能显示这种多模式表征的皮质区域。
