Department of Neurology, Xuan Wu Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory of Neuromodulation, Beijing, China.
The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China.
Sleep Med. 2018 May;45:132-139. doi: 10.1016/j.sleep.2017.12.016. Epub 2018 Feb 27.
The hubs of the brain network play a key role in integrating and transferring information between different functional modules. However, whether the changed pattern in functional network hubs contributes to the onset of leg discomfort symptoms in restless legs syndrome (RLS) patients remains unclear. Using resting-state functional magnetic resonance imaging (rs-fMRI) and graph theory methods, we investigated whether alterations of hubs can be detected in RLS.
First, we constructed the whole-brain voxelwise functional connectivity and calculated a functional connectivity strength (FCS) map in each of 16 drug-naive idiopathic RLS patients and 26 gender- and age-matched healthy control (HC) subjects. Next, a two-sample t test was applied to compare the FCS maps between HC and RLS patients, and to identify significant changes in FCS in RLS patients. To further elucidate the corresponding changes in the functional connectivity patterns of the aberrant hubs in RLS patients, whole-brain resting-state functional connectivity analyses for the hub areas were performed.
The hub analysis revealed decreased FCS in the cuneus, fusiform gyrus, paracentral lobe, and precuneus, and increased FCS in the superior frontal gyrus and thalamus in idiopathic drug-naive RLS patients. Subsequent functional connectivity analyses revealed decreased functional connectivity in sensorimotor and visual processing networks and increased functional connectivity in the affective cognitive network and cerebellar-thalamic circuit. Furthermore, the mean FCS value in the superior frontal gyrus was significantly correlated with Hamilton Anxiety Rating Scale scores in RLS patients, and the mean FCS value in the fusiform gyrus was significantly correlated with Hamilton Depression Rating Scale scores.
These findings may provide novel insight into the pathophysiology of RLS.
脑网络的枢纽在整合和在不同功能模块之间传递信息方面起着关键作用。然而，在不宁腿综合征（RLS）患者中，功能网络枢纽的变化模式是否有助于腿部不适症状的发作尚不清楚。使用静息态功能磁共振成像（rs-fMRI）和图论方法，我们研究了 RLS 中是否可以检测到枢纽的改变。
首先，我们构建了全脑体素水平的功能连接，并计算了 16 名未经药物治疗的特发性 RLS 患者和 26 名性别和年龄匹配的健康对照（HC）受试者的每个受试者的功能连接强度（FCS）图。然后，我们应用两样本 t 检验比较 HC 和 RLS 患者的 FCS 图，并确定 RLS 患者的 FCS 中的显著变化。为了进一步阐明 RLS 患者异常枢纽的功能连接模式的相应变化，我们对枢纽区域进行了全脑静息态功能连接分析。
枢纽分析显示，特发性未经药物治疗的 RLS 患者的楔前叶、梭状回、顶叶和后扣带回的 FCS 降低，而额上回和丘脑的 FCS 增加。随后的功能连接分析显示，感觉运动和视觉处理网络的功能连接降低，情感认知网络和小脑-丘脑回路的功能连接增加。此外，RLS 患者额上回的平均 FCS 值与汉密尔顿焦虑量表评分显著相关，而梭状回的平均 FCS 值与汉密尔顿抑郁量表评分显著相关。
这些发现可能为 RLS 的病理生理学提供新的见解。
