Surgery appears currently a treatment of choice in several brain lesions, especially tumors, on condition that the resection is the largest possible. However, due to the infiltrative behaviour of many tumors, in particular (low-grade) gliomas, to the frequent location within eloquent areas, and because of an interindividual anatomo-functional variability, functional mapping methods are used to taylor the resection according to cortico-subcortical functional boundaries. Consequently, in addition to the preoperative functional neuroimaging for the surgical planning, intraoperative electrical stimulations can be used during resection, eventually under local anesthesia on awake patient iflanguage and other cognitive functions need to be mapped. Indeed, this is an easy, accurate,reliable and safe technique of detection of both cortical and subcortical structures essential for the function. Thus, stimulations have boundaries, allowing to optimize the quality of lesion removal while minimizing the risk to induce a permanent postoperative neurological deficit (i.e. to optimize the ratio: benefit / risk). Moreover, intraoperative stimulations can be combined with peri-operative functional neuroimaging methods (fMRI, PET, MEG, DTI), before and after surgery, in order to improve the reliability of the pre-operative planning, but also with the goal to better understand both the short-term and long-term plasticity mechanisms associating functional cortical reshaping and connectivity changes-due initially to the tumor growth, then to its surgical resection.Finally, modelisations of such phenomena may help to improve the planning of future surgeries.%手术是脑内可切除性病变,尤其是脑肿瘤的首选治疗方法之一.然而,由于许多肿瘤具有侵袭性,尤其是(低级别)胶质瘤,病灶常侵犯脑功能区;另外由于个体之间存在解剖和功能的变异,故需应用脑功能定位方法定位脑功能区皮质及皮质下边界,用以个体化指导切除范围.除术前可采用功能成像(fMRI)进行术前计划外,切除肿瘤过程中还可应用术中电刺激,当需定位病人的语言区和其他认知功能区时,可使用局部麻醉.术中电刺激是一种确定脑功能区皮质及皮质下结构简单、准确、可信度高的安全方法,具有以下特点:①切除肿瘤前可定位每一个病人的功能区皮质;②了解被病灶侵犯区域,如辅助运动区、岛叶、运动前皮质、缘上回及角回的的病理生理功能;③在整个切除病灶过程中,可持续定位皮质下结构,用以了解解剖与功能的联系(皮质-皮质环及皮质-皮质下环路);④利用皮质重复电刺激可实时研究短期可塑性机制;⑤可根据功能界线进行病灶切除,以最大程度切除病灶,并尽量减小术后永久性功能障碍的风险,提高效益/风险比.此外,术中电刺激还可与围手术期各种功能神经影像技术相结合,如fMRI、PET、脑磁图(MEG)、矢量专题信息(digitalthematicinformation,DTI),用以提高术前计划的可靠性,帮助了解因肿瘤生长及手术切除过程中短期和长期内功能区皮质重塑及连接性改变的机理.该模式从而可最终改善手术计划.
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