Electrical stimulation of motor cortex for pain control:: a combined PET-scan and electrophysiological study
Electrical stimulation of motor cortex for pain control:: a combined PET-scan and electrophysiological study
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DOI：
10.1016/s0304-3959(99)00114-1
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发表时间：
1999-11-01
期刊：
影响因子：
7.4
通讯作者：
Laurent, B
中科院分区：
文献类型：
--
作者：
García-Larrea, L;Peyron, R;Laurent, B
虽然中央前回（MCS）的电刺激正在成为一种有前途的疼痛控制技术，其作用机制仍然不清楚，其应用主要是经验。使用正电子发射断层扫描（PET），我们研究了10例接受运动皮层刺激疼痛控制的患者的脑血流（rCBF）的区域变化，其中7例还接受了体感诱发电位和伤害性脊髓反射记录。最显着的MCS相关的rCBF增加涉及腹侧丘脑，可能反映了运动区的皮质-丘脑连接。内侧丘脑、前扣带/眶额皮质、前额叶和上脑干的CBF也有增加;相反，刺激电极下方的运动区CBF没有明显变化。在MCS过程中，来自SI的体感诱发电位保持稳定，在体感皮层中未观察到rCBF变化。我们的研究结果表明，下行轴突，而不是顶端树突，主要激活MCS，并强调丘脑作为关键结构介导的功能MCS的影响。MCS行动的模型提出，从而激活丘脑核直接与运动和运动前皮质将需要一系列的突触事件在疼痛相关的结构接收传入从这些核，包括内侧丘脑，前扣带和上脑干。MCS可以通过扣带回/眶额激活的方式影响慢性疼痛的情感-情绪成分，并通过激活脑干导致疼痛冲动的下行抑制，也通过脊髓屈曲反射的衰减来表明。相反，我们的研究结果不能证实MICS激活躯体感觉皮层的假设。(C)1999年国际疼痛研究协会。出版社：Elsevier Science B. V.
Although electrical stimulation of the precentral gyrus (MCS) is emerging as a promising technique for pain control, its mechanisms of action remain obscure, and its application largely empirical. Using positron emission tomography (PET) we studied regional changes in cerebral flood flow (rCBF) in 10 patients undergoing motor cortex stimulation for pain control, seven of whom also underwent somatosensory evoked potentials and nociceptive spinal reflex recordings. The most significant MCS-related increase in rCBF concerned the ventral-lateral thalamus, probably reflecting cortico-thalamic connections from motor areas. CBF increases were also observed in medial thalamus, anterior cingulate/orbitofrontal cortex, anterior insula and upper brainstem; conversely, no significant CBF changes appeared in motor areas beneath the stimulating electrode. Somatosensory evoked potentials from SI remained stable during MCS, and no rCBF changes were observed in somatosensory cortex during the procedure. Our results suggest that descending axons, rather than apical dendrites, are primarily activated by MCS, and highlight the thalamus as the key structure mediating functional MCS effects. A model of MCS action is proposed, whereby activation of thalamic nuclei directly connected with motor and premotor cortices would entail a cascade of synaptic events in pain-related structures receiving afferents from these nuclei, including the medial thalamus, anterior cingulate and upper brainstem. MCS could influence the affective-emotional component of chronic pain by way of cingulate/orbitofrontal activation, and lead to descending inhibition of pain impulses by activation of the brainstem, also suggested by attenuation of spinal flexion reflexes. In contrast, the hypothesis of somatosensory cortex activation by MICS could not be confirmed by our results. (C) 1999 International Association for the Study of Pain. Published by Elsevier Science B.V.