Service de Physiologie, Explorations Fonctionnelles, Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris, 51 avenue de Lattre de Tassigny, Créteil, France.
Brain Stimul. 2009 Jul;2(3):138-48. doi: 10.1016/j.brs.2009.01.002. Epub 2009 Feb 28.
Neuropathic pain results from injury to the central or peripheral nervous system and can prove itself refractory to classical medical treatment by anticonvulsants and antidepressants. In such cases, motor cortex stimulation is among the neurostimulation techniques available for its symptomatic control. This technique is based on surgical implantation of electrodes over the motor cortical representation of the painful area. Image-guided navigation is used for precise identification of the motor cortex intraoperatively, but proper placement of the electrodes is usually ensured by electrophysiologic mapping. This article details the intraoperative electrophysiologic procedure that we currently use for refining electrode placement in the epidural space, including the recording of somatosensory and motor-evoked potentials (MEPs). Various procedures have been reported and some groups are using direct cortical mapping and subdural electrode placement rather than epidural. Our method is one of several proposed techniques and is mostly based on intraoperative MEP mapping in response to monopolar (anodal) epidural stimulation of the cortex. The limit of this approach is that MEPs cannot be recorded in patients with total or severe motor deficit. We have shown that intraoperative mapping of the cortical region corresponding to the painful area by recording MEPs could help select contacts to be activated for chronic stimulation. Therefore, the patients in whom intraoperative MEP mapping is possible could benefit from this technique, at least if we consider that it improves the accuracy of electrode placement and that motor cortex stimulation efficacy critically depends on this placement.
神经性疼痛源于中枢或外周神经系统的损伤，且可能对经典的抗惊厥和抗抑郁药物治疗产生抗药性。在这种情况下，运动皮层刺激是可用于症状控制的神经刺激技术之一。这种技术基于在疼痛区域的运动皮层代表区植入电极。术中使用影像引导导航来精确识别运动皮层，但通常通过电生理图来确保电极的适当放置。本文详细介绍了我们目前用于细化硬膜外空间电极放置的术中电生理程序，包括体感诱发电位和运动诱发电位（MEPs）的记录。已经报道了各种程序，有些小组正在使用直接皮层映射和硬膜下电极放置而不是硬膜外。我们的方法是提出的几种技术之一，主要基于对皮层的单极（阳极）硬膜外刺激的术中 MEP 映射。这种方法的局限性在于，对于完全或严重运动功能障碍的患者，无法记录 MEP。我们已经证明，通过记录 MEPs 对疼痛区域对应的皮层区域进行术中映射，可以帮助选择要用于慢性刺激的触点。因此，对于能够进行术中 MEP 映射的患者，至少可以考虑到它提高了电极放置的准确性，并且运动皮层刺激的效果在很大程度上取决于这种放置，他们可能会受益于该技术。
