Cortical morphometric changes associated with completeness, level, and duration of spinal cord injury in humans: A case–control study

Abstract

Objective This study investigated how the injury completeness, level, and duration of spinal cord injury (SCI) affect cortical morphometric changes in humans. Methods T1‐weighted images were acquired from 59 SCI patients and 37 healthy controls. Voxel‐based morphometry analyses of the gray matter volume (GMV) were performed between SCI patients and healthy controls, complete SCI and incomplete SCI, and tetraplegia and paraplegia. Correlation analyses were performed to explore the associations between GMV and clinical variables in SCI patients. Results Compared to healthy controls, SCI patients showed decreased GMV in bilateral middle frontal gyrus, left superior frontal gyrus (SFG), left medial frontal gyrus in the whole‐brain analysis, while increased GMV in right supplementary motor area and right pallidum in ROI analysis. The complete SCI had lower GMV in left primary somatosensory cortex (S1) and higher GMV in left primary motor cortex compared with incomplete SCI. Lower GMV was identified in left thalamus and SFG in tetraplegia than that in paraplegia. Moreover, time since injury was positive with the GMV in right pallidum, positive correlations were observed between the GMV in bilateral S1 and total motor and sensory scores, whereas the GMV in left cuneus was negatively correlated with total motor and sensory scores in SCI patients. Conclusions The study provided imaging evidence for identifying cerebral structural abnormalities in SCI patients and significant differences in complete/incomplete and paraplegia/tetraplegia subgroups. These results suggested brain structural changes occur after SCI and these changes may depend on the injury completeness, level, and duration.

Brain morphology changes after spinal cord injury: A voxel-based meta-analysis

“…Our study demonstrated gray matter atrophy in the bilateral thalamus, which was in accordance with previous VBM studies and meta-analyses ( 23 , 34 – 36 ). Although neurons in the brain are not disrupted directly following SCI, the afferent motor pathway and efferent sensory pathway undergo degenerative processes ( 37 , 38 ).…”

“…Other VBM studies did not detect any brain alterations in SCI patients relative to the brains of healthy controls ( 21 , 22 ). Previous VBM study also uncovered that various clinical characteristics including injury level, severity, and duration can affect the brain alterations after SCI ( 23 ). In fact, most neuroimaging studies on SCI showed list of limitations including small cohort sizes (<20 patients), differences in patient characteristics (i.e., level and severity of injury), image acquisition, and post processing techniques, which may lead to inconsistent results and statistical inefficiency ( 4 , 24 ).…”

NT3 treatment alters spinal cord injury-induced changes in the gray matter volume of rhesus monkey cortex

“…SFG is involved in various cognitive and motor control tasks 65 , 66 , whereas IFG is involved in resolving the conflict between motor intention and sensory feedback 59 . Structural atrophy in these regions after SCI has been widely reported 14 , 21 , 46 . ACC is involved in the encoding of emotional information on pain and descending pain modulation 49 , and its structural atrophy is common in NP patients post-SCI 20 , 50 .…”

“…MFG is involved in executive function and emotional regulation 57 , 58 , whereas IFG is involved in resolving the conflict between motor intention and sensory feedback 59 . Many studies have reported the atrophy of GMV of MFG and IFG in SCI patients compared with the control 14 , 21 , 46 , 60 . Our previous publication has demonstrated that NT3/chitosan treatment can promote the recovery of motor function in animals 31 , and these structural alterations in motion-related brain regions may contribute to this process.…”

“…Besides the intensive exploration of classical sensorimotor pathways 18 , researchers focusing on VBM post-SCI have recently been exploring common post-SCI complications, such as NP 19 , 20 , psychological, cognitive impairment 13 , 15 , and their related brain regions. Meanwhile, several studies have explored the possible effects of factors, such as the extent, level, and duration of SCI, on the cortical alterations in patients to address the discrepancy among outcomes reported in different publications 14 , 21 ; these studies further demonstrated the complexity of structural and functional changes within the brain post-SCI.…”