基于皮质脑电的大脑皮层运动功能区定位

Motor Cortex Functional Mapping Using Electrocorticography

针对神经外科手术中用皮层电刺激(ECS)法确认病灶周边运动功能区时存在操作时间长、可能损伤皮层以及诱发癫痫等缺陷,本研究提出一种基于皮质脑电(ECoG)分析的皮层运动功能区定位方法。该研究先对ECoG进行功率谱估计,分析Mu节律在运动前后的特征;再采用多分辨率小波分析方法提取特征并量化,观察各导联特征总量的分布,得到各导联电极下皮层与运动功能区的相关程度。分析结果显示,各电极下皮层与运动功能区的相关程度的分布与ECS的结果基本一致,且此定位方法的总操作时间大约为5min。这表明基于ECoG的被动大脑皮层运动功能区定位方法,很可能成为术中ECS法的一种有效辅助定位手段。

The main shortcomings of using electrocortical stimulation （ECS） in identifying the motor functional area around the focus in neurosurgery are certainly time-consuming, possibly cerebral cortex injuring and perhaps triggering epilepsy. To solve these problems, we in our research presented an intraoperative motor cortex functional mapping based on electrocorticography （ECoG）. At first, using power spectrum estimation, we analyzed the characteristic of ECoG which was related to move task, and selected Mu rhythm as the move-related feature. Then we extracted the feature from original ECoG by multi-resolution wavelet analysis. By calculating the sum value of feature in every channel and observing the distribution of these sum values, we obtained the correlation between the cortex area under the electrode and motor cortex functional area. The results showed that the distribution of the relationship between the cortex under the electrode and motor cortex functional area was almost consistent with those identified by ECS which was called as ＇the gold-standard＇. It indicated that this method was basically feasible, and it just needed five minutes totally. In conclusion, ECoG-based and passive identification of motor cortical function may serve as a useful adjunct to ECS in the intraoperative mapping.