Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
Department of Radiology, Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
Nat Commun. 2020 Aug 7;11(1):3948. doi: 10.1038/s41467-020-17788-z.
Thalamocortical dysrhythmia is a key pathology of chronic neuropathic pain, but few studies have investigated thalamocortical networks in chronic low back pain (cLBP) given its non-specific etiology and complexity. Using fMRI, we propose an analytical pipeline to identify abnormal thalamocortical network dynamics in cLBP patients and validate the findings in two independent cohorts. We first identify two reoccurring dynamic connectivity states and their associations with chronic and temporary pain. Further analyses show that cLBP patients have abnormal connectivity between the ventral lateral/posterolateral nucleus (VL/VPL) and postcentral gyrus (PoCG) and between the dorsal/ventral medial nucleus and insula in the less frequent connectivity state, and temporary pain exacerbation alters connectivity between the VL/VPL and PoCG and the default mode network in the more frequent connectivity state. These results extend current findings on thalamocortical dysfunction and dysrhythmia in chronic pain and demonstrate that cLBP pathophysiology and clinical pain intensity are associated with distinct thalamocortical network dynamics.
丘脑皮质节律紊乱是慢性神经性疼痛的关键病理学特征，但由于慢性下腰痛（cLBP）的病因非特异性且复杂，很少有研究调查其丘脑皮质网络。本研究使用 fMRI 提出了一种分析管道，以识别 cLBP 患者异常的丘脑皮质网络动态，并在两个独立队列中验证研究结果。我们首先确定了两种反复出现的动态连通状态及其与慢性和暂时性疼痛的关联。进一步的分析表明，cLBP 患者在较少出现连通状态时，其腹侧外侧/后外侧核（VL/VPL）和后中央回（PoCG）之间以及背侧/腹内侧核和岛叶之间的连通性异常，而暂时性疼痛加剧会改变更频繁连通状态下 VL/VPL 和 PoCG 之间以及默认模式网络之间的连通性。这些结果扩展了目前关于慢性疼痛中丘脑皮质功能障碍和节律紊乱的发现，并表明 cLBP 病理生理学和临床疼痛强度与独特的丘脑皮质网络动态相关。
