脑辅助运动区手术后运动网络重塑的机制研究

The distribution of human motor cortex and connectivity of motor network show extraordinary complexity and plasticity. Supplementary motor area (SMA) plays both important anatomical and functional roles in the motor network. Surgical resection of SMA leads to characteristic transient postoperative deficits, demonstraing as complete or almost complete recovery within a few weeks or months, known as the SMA syndrome. It is of utmost importance for the neurosurgeon to early determine the characteristics of the SMA syndrome and inform patients about the risk of its occurrence and its typical course of recovery in the preoperative period. However, the mechanisms underlying the recovery process of SMA syndrome have not been elucidated and it’s hard to predict its occurence. Based on the rich experience of brain functional neuroimaging and patient-specific surgery for brain tumor within motor areas, we will combine the up-to-date technologies, including diffusion spectroscopy Imaging (DSI) and resting-state fMRI (rest-fMRI) to determine the structural and functional reconstruction of motor network which might be the mechanism of SMA syndrome. For surgical resection of SMA tumors, perioperative dynamic changes of motor network were examined and compared with the characteristics of motor deficit to determine the relationship of motor network characteristics and motor recovery. Animal model of SMA syndrome will be made by performing the parallel surgeries on monkeys to observe the motor network reconstruction. The neural fibers in the brain will be traced to determine its structural basis. This study can not only explore the mechanism underlying the motor recovery process of SMA syndrome, but also promote the development of the science in protection, reconstruction and rehabilitation of brain function.

脑运动网络构筑极具复杂性和可塑性，辅助运动区（SMA）在运动网络解剖和功能上起重要作用。手术切除SMA导致特征性的一过性运动功能障碍，在术后几周或几月内完全或基本完全恢复，称为SMA综合征。早期诊断SMA综合征并在围手术期告知患者其发生的风险及恢复特点意义重大。然而，SMA综合征的机制尚未明确，无法准确预知。基于前期脑功能成像及运动区脑肿瘤个体化手术治疗的成熟经验，本项目联合应用磁共振频谱成像及静息态fMRI技术构筑脑结构与功能网络，探讨SMA综合征运动网络的重塑机制。研究围术期SMA脑肿瘤手术运动网络的动态变化并与运动功能比较，探讨运动网络重塑与SMA综合征运动功能恢复的相关性。对猴开展同样的手术制作SMA综合征动物模型，观察运动网络重塑；猴处死后脑行神经纤维追踪，探讨重塑的结构基础。本研究不仅可明确SMA综合征运动功能恢复进程的发生机制，还有助于促进脑功能保护、重建与康复等科学的发展。

脑运动网络构筑极具复杂性和可塑性，辅助运动区（SMA）在运动网络解剖和功能上起重要作用。手术切除SMA导致特征性的一过性运动功能障碍，在术后几周或几月内完全或基本完全恢复，称为SMA综合征。早期诊断SMA综合征并在围手术期告知患者其发生的风险及恢复特点意义重大。然而，SMA综合征的机制尚未明确，无法准确预知。病变脑为了解大脑的工作方式提供了独特的机会。然而，在变形大脑中定位脑功能仍然是困难的，这阻碍了发现大脑作用机制和神经系统疾病患者新型治疗方法的发展。在这里，我们提出了一个功能映射方法，使用功能连接特点以精确定位对侧半球的功能区。通过进行一系列实验，验证了该方法的可重复性和可靠性，并在样本交叉检验和独立样本检验中证明了其高精度。辅助运动区（SMA）定位的准确率可以达到86%。并且在不同数据集上进行了验证，交叉验证时每准确率高达89%。对于同一被试前后两次静息态数据的定位结果有很高的重合度（平均Dice 系数 80%）表现出算法对于个体的稳定性。静息态定位结果和术中直接电刺激的比较得出该定位算法特异性达到90%。将该定位方法用于SMA区脑胶质瘤病患，手术前、后患者的肌力与定位的 post-SMA体积大小正相关 (R = 0.6840, P = 0.0009)，与pre-SMA及mid-SMA无相关性。控制年龄，性别，肿瘤级别后，post-SMA体积与肌力仍有相关性 (P = 0.0041)。在训练集上，定位的SMA大小判断胶质瘤的高低级别，可以得到81.4%的检验准确率。直接用于测试集，我们可以得到84.6%的准确率。我们同时采用同步fMRI和脑深部刺激, 显示左侧额叶皮质和顶叶皮质可持续同步激活。我们期望所提出的功能映射算法对临床实践和脑功能定量研究具有广泛的适用性。