Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, Nevada, USA.
Department of Neurosciences, University of California San Diego, La Jolla, California, USA.
J Neuroimaging. 2023 Jul-Aug;33(4):547-557. doi: 10.1111/jon.13107. Epub 2023 Apr 20.
Resting-state functional MRI (rs-fMRI) studies in Parkinson's disease (PD) patients with freezing of gait (FOG) have implicated dysfunctional connectivity over multiple resting-state networks (RSNs). While these findings provided network-specific insights and information related to the aberrant or altered regional functional connectivity (FC), whether these alterations have any effect on topological reorganization in PD-FOG patients is incompletely understood. Understanding the higher order functional organization, which could be derived from the "hub" and the "rich-club" organization of the functional networks, could be crucial to identifying the distinct and unique pattern of the network connectivity associated with PD-FOG.
In this study, we use rs-fMRI data and graph theoretical approaches to explore the reorganization of RSN topology in PD-FOG when compared to those without FOG. We also compared the higher order functional organization derived using the hub and rich-club measures in the FC networks of these PD-FOG patients to understand whether there is a topological reorganization of these hubs in PD-FOG.
We found that the PD-FOG patients showed a noticeable reorganization of hub regions. Regions that are part of the prefrontal cortex, primary somatosensory, motor, and visuomotor coordination areas were some of the regions exhibiting altered hub measures in PD-FOG patients. We also found a significantly altered feeder and local connectivity in PD-FOG.
Overall, our findings demonstrate a widespread topological reorganization and disrupted higher order functional network topology in PD-FOG that may further assist in improving our understanding of functional network disturbances associated with PD-FOG.
帕金森病（PD）伴冻结步态（FOG）患者的静息态功能磁共振成像（rs-fMRI）研究表明，多个静息态网络（RSNs）的连接功能存在障碍。虽然这些发现提供了与异常或改变的局部功能连接（FC）相关的网络特定见解和信息，但这些改变是否对 PD-FOG 患者的拓扑重组织有任何影响尚不完全清楚。了解更高阶的功能组织，这些组织可能源于功能网络的“枢纽”和“富集群”组织，对于识别与 PD-FOG 相关的独特网络连接模式可能至关重要。
在这项研究中，我们使用 rs-fMRI 数据和图论方法，比较了 PD-FOG 患者与无 FOG 患者之间 RSN 拓扑的重组。我们还比较了这些 PD-FOG 患者 FC 网络中使用枢纽和富集群测量值得出的高阶功能组织，以了解这些枢纽在 PD-FOG 中是否存在拓扑重组织。
我们发现 PD-FOG 患者的枢纽区域出现了明显的重组。参与前额叶皮层、初级体感、运动和运动视觉协调区域的区域是 PD-FOG 患者中表现出改变枢纽指标的区域之一。我们还发现 PD-FOG 中的馈送和局部连通性发生了显著改变。
总的来说，我们的发现表明 PD-FOG 中存在广泛的拓扑重组织和破坏的高阶功能网络拓扑结构，这可能有助于进一步提高我们对与 PD-FOG 相关的功能网络障碍的理解。
