Mandloi Shreya, Syed Mashaal, Shoraka Omid, Ailes Isaiah, Kang Ki Chang, Sathe Anish, Heller Joshua, Thalheimer Sara, Mohamed Feroze B, Sharan Ashwini, Harrop James, Krisa Laura, Matias Caio, Alizadeh Mahdi
Department of Neurological Surgery, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
Thomas Jefferson Integrated Magnetic Resonance Imaging Center, Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
J Neuroimaging. 2023 Sep-Oct;33(5):781-791. doi: 10.1111/jon.13117. Epub 2023 May 15.
Spinal cord injury (SCI) results in the loss of motor and sensory function from disconnections between efferent and afferent pathways. Most SCI patients are affected with chronic neuropathic pain, but there is a paucity of data concerning neuroplastic changes following SCI. Chronic pain disrupts default networks and is associated with abnormal insular connectivity. The posterior insula (PI) is associated with the degree of pain and intensity of pain. The anterior insula (AI) is related to signal changes. Comprehension of SCI pain mechanisms is essential to elucidate effective treatment options.
This study examines the insular gyri functional connectivity (FC) of seven (five male, two female) SCI participants with moderate-severe chronic pain compared to 10 (five male, five female) healthy controls (HC). All subjects had 3-Tesla MRI performed and resting-state functional MRI (fMRI) was acquired. FC metrics were obtained from the comparisons of resting-state fMRI among our various groups. A seed-to-voxel analysis was pursued, encompassing six gyri of the insula. For multiple comparisons, a correction was applied with a significance level of p < .05.
There were significant differences in FC of the insula between SCI participants with chronic pain compared with HC. In the SCI participants, there was hyperconnectivity of the AI and PI to the frontal pole. In addition, there was increased FC noted between the PI and the anterior cingulate cortex. Hyperconnectivity was also observed between the AI and the occipital cortex.
These findings illustrate that there is a complex hyperconnectivity and modulation of pain pathways after traumatic SCI.
脊髓损伤（SCI）会导致传出和传入通路中断，进而造成运动和感觉功能丧失。大多数脊髓损伤患者会遭受慢性神经性疼痛，但关于脊髓损伤后神经可塑性变化的数据却很匮乏。慢性疼痛会破坏默认网络，并与岛叶连接异常有关。后岛叶（PI）与疼痛程度和疼痛强度相关。前岛叶（AI）与信号变化有关。理解脊髓损伤疼痛机制对于阐明有效的治疗方案至关重要。
本研究对7名（5名男性，2名女性）患有中度至重度慢性疼痛的脊髓损伤参与者与10名（5名男性，5名女性）健康对照者（HC）的岛叶回功能连接性（FC）进行了研究。所有受试者均接受了3特斯拉磁共振成像检查，并采集了静息态功能磁共振成像（fMRI）。通过对不同组之间静息态fMRI的比较获得FC指标。进行了种子点到体素分析，涵盖岛叶的六个脑回。对于多重比较，采用了显著性水平为p < 0.05的校正。
与健康对照者相比，患有慢性疼痛的脊髓损伤参与者的岛叶FC存在显著差异。在脊髓损伤参与者中，前岛叶和后岛叶与额极的连接增强。此外，后岛叶与前扣带回皮质之间的FC增加。前岛叶与枕叶皮质之间也观察到连接增强。
这些发现表明，创伤性脊髓损伤后疼痛通路存在复杂的连接增强和调节。
