慢性脊髓损伤后脑结构重塑的磁共振成像研究

目的 联合应用基于体素的形态学 (VBM) 研究和扩散张量成像(DTI)探讨慢性脊髓损伤(SCI)患者全脑灰、白质变化规律。方法 对20例慢性SCI患者(SCI组)和30名健康志愿者(对照组)行全脑容积及DTI扫描,分析患者全脑灰、白质结构改变及纤维束完整性的变化。结果 与对照组比较,SCI组脑灰质体积减小区域主要有左侧初级运动皮层(M1)、左侧运动前区(PMA)、右侧前扣带回、右侧直回、左侧额下回、右侧颞下回、左侧枕中回及右侧楔前叶 (P<0.001)。白质体积减小的区域主要有:双侧辅助运动区、双侧锥体束走行区、左侧M1及胼胝体 (P<0.001)。FA值减小的区域主要有胼胝体干、左侧内囊前肢及左侧顶下小叶。MD值增高的区域主要为胼胝体干,MD值减小的区域为右侧顶下小叶缘上回(P<0.001)。结论 慢性SC的相关脑结构区发生改变,与认知、情绪、空间定位功能相关脑区的灰、白质结构发生改变,其中胼胝体对结构的重塑可能起着重要作用。联合使用VBM及DTI可显示慢性SCI后脑结构的重塑。

Reorganization of brain structure after chronic spinal cord injury: A magnetic resonance imaging study

Objective To explore the brain structural changes of chronic spinal cord injury (SCI) patients combined with voxel-based morphometry (VBM) and diffusion tensor imaging (DTI). Methods Twenty chronic SCI patients were recruited as SCI group, and 30 healthy people were recruited as control group. The DTI and VBM images of all subjects were analyzed to explore the volume changes of gray and white matter, and the axonal integrity changes of cerebral fibers. Results VBM revealed that SCI patients exhibited a decrease in the gray matter volume mainly in the left primary motor cortex (M1), premotor area (PMA), right anterior cingulate cortex, right gyrus rectus, left inferior frontal gyrus, right inferior temporal gyrus, the left middle occipital gyrus and the right precuneus (P<0.001). Patients also exhibited a decrease in the white matter volume mainly in the bilateral supplementary motor area, bilateral pyramidal tract, the left M1 and the corpus callosum (P<0.001). DTI revealed that the FA value of the trunk of corpus callosum, left internal capsule forelimb and left inferior parietal lobule reduced, while MD value of the trunk of corpus callosum increased (P<0.001). Conclusion The structures of the brain are changed after chronic SCI, and the changes are not limited to the motor-related area. The corpus callosum may play important role in structural remodeling. The combination of VBM and DTI can reveal the evolution of brain structures after chronic SCI.