Zheng Weipeng, Xu Fangtian, Chen Haoyi, Wang Ning, Xiao Wende, Liang YingJie, Wen Shifeng
1 Department of Orthopedics, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou, Guangdong, PR China.
2 Department of Orthopedics, The First Affiliated Hospital of Gannan Medical University, Ganzhou, PR China.
Acta Radiol. 2019 May;60(5):653-662. doi: 10.1177/0284185118795335. Epub 2018 Aug 24.
Diffusion tensor imaging (DTI) provides information about water molecule diffusion in spinal cord.
This study was aimed to investigate DTI changes in the different stages of compressive spinal cord induced by water-absorbing material implantation.
The spinal cord compression was administered over the fourth cervical vertebral level in rat. Rat models were divided into five subgroups according to compression stages: sham group, group A: three-day compression rat models; group B: 12-day compression rat models; group C: 20-day compression rat models; group D: 60-day compression rat models. DTI including fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in the compressive spinal cord were collected. The relationship between the Basso, Beattie, and Bresnahan (BBB) scores and DTI metrics was further explored.
Compared with the sham group, BBB scoring of rat model showed a decreased tendency from group A ( P < 0.05) to group B ( P < 0.05). Then the motor function of rat model hindlimbs was recovered in some degree from group C ( P < 0.05) to group D ( P < 0.05) but had significant motor defects when compared with the normal level ( P < 0.05). The DTI metrics results revealed that chronic spinal cord compression resulted in lower FA value and higher ADC value at the compressive spinal cord level assessed at all four time-points ( P < 0.05). DTI metrics also showed a close correlation with motor function ( P < 0.05).
DTI is an optimal pre-clinical imaging tool to reflect locomotor performance and pathological status of compressive spinal cord epicenter in chronic spinal cord compression rat model.
扩散张量成像（DTI）可提供脊髓中水分子扩散的信息。
本研究旨在探讨吸水材料植入诱导的脊髓压迫不同阶段的DTI变化。
在大鼠第四颈椎水平进行脊髓压迫。大鼠模型根据压迫阶段分为五个亚组：假手术组、A组：三天压迫大鼠模型；B组：12天压迫大鼠模型；C组：20天压迫大鼠模型；D组：60天压迫大鼠模型。收集压迫脊髓中的DTI，包括分数各向异性（FA）和表观扩散系数（ADC）。进一步探讨Basso、Beattie和Bresnahan（BBB）评分与DTI指标之间的关系。
与假手术组相比，大鼠模型的BBB评分从A组（P < 0.05）到B组（P < 0.05）呈下降趋势。然后，大鼠模型后肢的运动功能从C组（P < 0.05）到D组（P < 0.05）有一定程度的恢复，但与正常水平相比仍有明显的运动缺陷（P < 0.05）。DTI指标结果显示，在所有四个时间点评估的压迫脊髓水平，慢性脊髓压迫导致较低的FA值和较高的ADC值（P < 0.05）。DTI指标也与运动功能密切相关（P < 0.05）。
DTI是反映慢性脊髓压迫大鼠模型中压迫脊髓中心运动性能和病理状态的最佳临床前成像工具。
