Barcia Juan A, Sanz Ana, Balugo Paloma, Alonso-Lera Pedro, Brin Juan Raúl, Yus Miguel, Gonzalez-Hidalgo Mercedes, Acedo Victoria M, Oliviero Antonio
Service of Neurosurgery, Institute of Neurosciences, San Carlos University Hospital, Complutense University of Madrid, Madrid, Spain.
Neuroreport. 2012 Mar 28;23(5):304-9. doi: 10.1097/WNR.0b013e3283513307.
Functional areas located near or within brain gliomas prevent the complete resection of these tumors. It has recently been described that slow tumor invasion promotes neural reorganization, and even topographic plasticity, allowing a staged resection of those tumors. Thus, our aim was to promote plasticity by mimicking the tumor's capability to displace brain function. This proceeded through the production of a 'virtual lesion' in eloquent areas within a tumor using continuous high-frequency cortical electrical stimulation (cHFCS). An anaplastic astrocytoma located in Broca's area progressed in a patient whose lateralization of language to the side of the lesion was demonstrated with functional MRI. After partial tumor resection using awake cortical monitoring, we implanted a subdural grid over the eloquent cortex located within residual tumor. We then applied cHFCS for 25 days, using a frequency of 130 Hz and a pulse width of 1 ms. Stimulus intensity was set to the threshold wherein mild speech disturbance was evident without any other neurological effects. This treatment successfully achieved the displacement of speech functions, and a more radical resection of the tumor was possible in a second surgery. Critically, a reorganization of motor language areas was demonstrated both with functional MRI and cortical stimulation. Furthermore, motor language areas were also identified in the right hemisphere, where previously they were absent. The patient's speech fluency improved both after stimulation and resection. We therefore demonstrate the first evidence of induced topographic plasticity using cHFCS in eloquent areas within a tumor, which allowed for increased tumor removal. Our results open the possibility to induce plasticity before the resection of brain tumors near eloquent areas, in order to increase the extent of resection.
位于脑胶质瘤附近或内部的功能区会妨碍这些肿瘤的完全切除。最近有研究表明，肿瘤的缓慢侵袭会促进神经重组，甚至是地形可塑性，从而使这些肿瘤能够分期切除。因此，我们的目标是通过模拟肿瘤转移脑功能的能力来促进可塑性。这是通过在肿瘤内的明确区域使用连续高频皮层电刺激（cHFCS）产生“虚拟病变”来实现的。一名位于布洛卡区的间变性星形细胞瘤患者，功能磁共振成像显示其语言功能向病变侧偏侧化。在使用清醒皮层监测进行部分肿瘤切除后，我们在残留肿瘤内的明确皮层上植入了硬膜下网格。然后，我们以130赫兹的频率和1毫秒的脉冲宽度应用cHFCS，持续25天。刺激强度设定为阈值，此时会出现轻微的言语障碍，但无任何其他神经学影响。这种治疗成功地实现了语言功能的转移，并且在第二次手术中可以更彻底地切除肿瘤。至关重要的是，功能磁共振成像和皮层刺激均显示了运动语言区的重组。此外，在以前不存在运动语言区的右半球也发现了运动语言区。刺激和切除后，患者的言语流畅性均有所改善。因此，我们首次证明了在肿瘤内的明确区域使用cHFCS诱导地形可塑性，这使得肿瘤切除范围得以扩大。我们的研究结果为在切除靠近明确区域的脑肿瘤之前诱导可塑性以扩大切除范围提供了可能性。
