9.4T下猴脊髓损伤后大脑结构可塑性的磁共振成像研究

脊髓损伤导致破坏性的感觉和运动功能缺失，严重影响病人的生存质量，并给社会造成沉重的经济负担。脊髓局部受到损伤后会诱发大脑结构和功能可塑性变化，其中结构改变会对损伤后功能重组产生重大影响，近年来引起国内外学者特别关注。然而，目前对脊髓损伤后大脑结构可塑性的研究缺乏直接有效的观察手段。高场下相位对比磁共振成像可以清楚地显示大脑皮质层状亚结构和灰质中的微小白质，可以应用到脊髓损伤后大脑结构变化研究中，但相关的研究未见有报道。本项目拟以猴脊髓损伤模型为研究对象，通过在9.4T高场下利用相位对比磁共振成像、磁共振波谱成像等技术结合组织病理学方法，对损伤后大脑结构可塑性变化进行研究。研究内容包括脊髓损伤后大脑结构变化、随时间演变过程及其代谢和细胞机制。研究结果将明确相位对比磁共振成像在大脑结构可塑性变化应用方面的价值，为进一步研究脊髓损伤后大脑功能可塑性变化、临床治疗方法提供重要的实验基础。

Spinal cord injury results in sensory and motor dysfunction below the level of lesion, affects patients' quality of life and imposes heavy economic costs on society. Injury at spinal cord segment can lead to brain structural and functional plastic changes. Studies show structural changes play their particularly important roles in functional reorganization, which have attracted more and more attention in recent years. However, direct methods for visualizing brain structural plasticity are lacking. Phase contrast magnetic resonance imaging (PC-MRI) at high field can detect cortical substructure and small white matter in gray matter. Thus, PC-MRI could be an ideal method to visualize brain structural changes after spinal cord injury. However, PC-MRI research in this field have not yet been reported. In this project, based on non-human primate monkey (an animal that is the closest living relative to human) spinal cord injury model, we propose to investigate long-term structural changes of monkey brain after spinal cord injury mainly using PC-MRI and Magnetic Resonance Spectroscopic Imaging at high field MRI system (9.4T), and finally combined with histological methods. Specific aims of the projects are: 1) to determine structural changes of cortex, white matter, and subcortical structure after monkey spinal cord injury, 2) to determine evolution of those structural changes, 3) to determine metabolic and celluar mechnism underlying brain structural changes.This research is designed to establish the value of PC-MRI in the study of brain structural plasticity after spinal cord injury, and to lay the foundation for future work related to investigation of brain functional plasticity and therapeutic strategies after spinal cord injury.