Department of Neurological Surgery, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
Jefferson Integrated Magnetic Resonance Imaging Center (JIMRIC), Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
J Neuroimaging. 2024 Nov-Dec;34(6):704-719. doi: 10.1111/jon.13237. Epub 2024 Sep 9.
Neuropathic pain (NP) is a debilitating condition following spinal cord injury (SCI). The role of periaqueductal gray (PAG) in NP development following SCI remains underexplored. Using resting-state functional MRI (rsfMRI), our study aimed to demonstrate the alterations in functional connectivity (FC) of PAG in NP following SCI.
Ten SCI patients (SCI + NP, n = 7, and SCI - NP, n = 3), alongside 10 healthy controls (HCs), were enrolled. rsfMRI was conducted followed by seed-to-voxel analysis using PAG as the seed region and then group-based analysis comprising three groups (SCI + NP, SCI - NP, and HC). Age and gender were considered as confounding variables.
Compared to HCs, SCI + NP demonstrated decreased FC between PAG and right insula, right frontal orbital cortex, right pallidum, dorsal raphe nucleus (DRN), red nuclei (RN), substantia nigra (SN), and ventral posterolateral (VPL) thalamic nuclei. Compared to SCI - NP, SCI + NP demonstrated increased FC between PAG and posterior cingulate cortex (PCC), hippocampus, cerebellar vermis lobules IV and V, and thalamic structures (posterior and lateral pulvinar, the mediodorsal nuclei, and the ventral lateral nuclei). Additionally, decreased FC between the PAG and VPL, geniculate bodies, intralaminar nuclei of thalamus, DRN, RN, SN, and prefrontal cortex was observed in this comparison.
Altered FC between PAG and right anterior insula, VPL, DRN, RN, SN, cerebellar vermis lobules IV and V, frontal cortex, and PCC was associated with NP sequelae of SCI. Additionally, SCI was independently associated with decreased FC between PAG and right posterior insula, cerebellar lobules IV and V, and cerebellar vermis lobules III, IV, and V.
神经性疼痛（NP）是脊髓损伤（SCI）后的一种使人虚弱的病症。在 SCI 后 NP 的发展中，导水管周围灰质（PAG）的作用仍未得到充分探索。使用静息态功能磁共振成像（rsfMRI），我们的研究旨在展示 SCI 后 NP 中 PAG 的功能连接（FC）的变化。
纳入 10 名 SCI 患者（SCI+NP，n=7 和 SCI-NP，n=3）和 10 名健康对照者（HCs）。进行 rsfMRI 后，使用 PAG 作为种子区域进行种子到体素分析，然后进行基于组的分析，包括三组（SCI+NP、SCI-NP 和 HCs）。考虑年龄和性别作为混杂变量。
与 HCs 相比，SCI+NP 显示 PAG 与右侧岛叶、右侧额眶皮质、右侧苍白球、中缝背核（DRN）、红核（RN）、黑质（SN）和腹后外侧（VPL）丘脑核之间的 FC 降低。与 SCI-NP 相比，SCI+NP 显示 PAG 与后扣带回皮质（PCC）、海马体、小脑蚓部 IV 和 V 以及丘脑结构（后和外侧丘脑枕、中背核和腹外侧核）之间的 FC 增加。此外，在这种比较中还观察到 PAG 与 VPL、丘脑核、丘脑内侧核、DRN、RN、SN 和前额皮质之间的 FC 降低。
PAG 与右侧前岛叶、VPL、DRN、RN、SN、小脑蚓部 IV 和 V、额叶皮质和 PCC 之间的 FC 改变与 SCI 的 NP 后遗症有关。此外，SCI 与 PAG 与右侧后岛叶、小脑 lobules IV 和 V 以及小脑蚓部 lobules III、IV 和 V 之间的 FC 降低独立相关。
