Division of Brain, Imaging, and Behaviour-Systems Neuroscience, Krembil Brain Institute, Krembil Research Institute, Toronto Western Hospital, University Health Network, Toronto, ON, Canada.
Institute of Medical Science, University of Toronto, Toronto, ON, Canada.
Pain. 2018 Nov;159(11):2267-2276. doi: 10.1097/j.pain.0000000000001332.
Pain is a prevalent and debilitating symptom of multiple sclerosis (MS); yet, the mechanisms underlying this pain are unknown. Previous studies have found that the functional relationships between the salience network (SN), specifically the right temporoparietal junction a SN node, and other components of the dynamic pain connectome (default mode network [DMN], ascending and descending pathways) are abnormal in many chronic pain conditions. Here, we use resting-state functional magnetic resonance imaging and measures of static and dynamic functional connectivity (sFC and dFC), and regional BOLD variability to test the hypothesis that patients with MS have abnormal DMN-SN cross-network sFC, dFC abnormalities in SN-ascending and SN-descending pathways, and disrupted BOLD variability in the dynamic pain connectome that relates to pain inference and neuropathic pain (NP). Thirty-one patients with MS and 31 controls completed questionnaires to characterize pain and pain interference, and underwent a resting-state functional magnetic resonance imaging scan from which measures of sFC, dFC, and BOLD variability were compared. We found that (1) ∼50% of our patients had NP features, (2) abnormalities in SN-DMN sFC were driven by the mixed-neuropathic subgroup, (3) in patients with mixed NP, dFC measures showed that there was a striking change in how the SN was engaged with the ascending nociceptive pathway and descending modulation pathway, (4) BOLD variability was increased in the DMN, and (5) the degrees of sFC and BOLD variability abnormalities were related to pain interference. We propose that abnormal SN-DMN cross-network FC and temporal dynamics within and between regions of the dynamic pain connectome reflect MS pain features.
疼痛是多发性硬化症（MS）的一种普遍且使人虚弱的症状；然而，这种疼痛的机制尚不清楚。先前的研究发现，突显网络（SN）的功能关系，特别是右侧颞顶联合作为 SN 节点，以及动态疼痛连接组（默认模式网络 [DMN]、上行和下行通路）的其他组成部分，在许多慢性疼痛情况下都是异常的。在这里，我们使用静息态功能磁共振成像和静态和动态功能连接（sFC 和 dFC）的测量值，以及区域 BOLD 变异性来检验以下假设：MS 患者的 DMN-SN 跨网络 sFC 异常、SN-上行和 SN-下行通路的 dFC 异常，以及与疼痛推断和神经性疼痛（NP）相关的动态疼痛连接组中的 BOLD 变异性中断。31 名 MS 患者和 31 名对照者完成了问卷以描述疼痛和疼痛干扰，并进行了静息态功能磁共振成像扫描，从中比较了 sFC、dFC 和 BOLD 变异性的测量值。我们发现：（1）约 50%的患者有 NP 特征；（2）SN-DMN sFC 的异常是由混合神经性亚组驱动的；（3）在混合 NP 患者中，dFC 测量值表明 SN 与上行伤害感受通路和下行调制通路的连接方式发生了明显变化；（4）DMN 中的 BOLD 变异性增加；（5）sFC 和 BOLD 变异性异常的程度与疼痛干扰有关。我们提出，SN-DMN 跨网络 FC 异常和动态疼痛连接组中区域内和区域间的时间动态反映了 MS 疼痛特征。
