摘要
目的用磁共振扩散张量成像(DTI)观察犬急性脊髓损伤后可降解支架及神经干细胞移植的作用。方法制作犬T13脊髓左半横断损伤模型。将18只犬分为假手术组(1)、对照组(5)、支架组(5)和干细胞组(7)。假手术组不损伤脊髓。对照组仅损伤脊髓,不做移植。损伤后1周时,干细胞组将填充Hoechst标记的神经干细胞的可降解支架植入损伤区;支架组仅植入可降解支架。分别于损伤前、损伤后1周、移植后1周(即损伤后2周)、移植后4周及移植后8周时行MRI检查,用DTI测量损伤侧和未损伤侧的表观扩散系数(ADC)值及部分各向异性(FA)值,并对结果进行统计学分析。DTI用SSFSE序列,b=500s/mm2,扩散敏感梯度方向为13。结果损伤前,脊髓左右两侧对比,ADC和FA值的差异无统计学意义。损伤后ADC值升高,FA值降低,随时间延长而逐渐恢复,干细胞组恢复更明显。移植后4周时,对照组脊髓左右两侧的ADC值和FA值的差异有统计学意义,支架组和干细胞组脊髓左右两侧的ADC值和FA值的差异无统计学意义。结论DTI对实验性脊髓损伤后脊髓损伤和修复过程的观察能提供有价值的信息。
Objective Using MR diffusion tensor imaging （DTI） to observe the effect of transplantation of degradable scaffold seeded with neural stem cells to acutely injured canine spinal cord. Methods Eighteen adult canines with left spinal cord hemisection at the level of T13 were divided into 4 groups： stem cell group （transplanted with scaffold seeded with neural stem cells, 7 dogs）, scaffold group （transplanted with scaffold only, 5 dogs）, control group （no transplantation postinjury, 5 dogs）, and sham-operation group （no injury, 1 dog）. They were examined by MR diffusion tensor imaging five times sequentially： prior to injury, 1 week after injury, 1 week after transplantation（that is, 2 weeks after injury）, 4 weeks after transplantation, and 8 weeks after transplantation, respectively. DTI was performed with single shot fast spin echo pulse sequence with 13 diffusion directions, b= 500 s/mmz. The apparent diffusion coefficient （ADC） values and fractional anisotrophy （FA） values were measured in both side of the spinal cord. Results Before injury, the ADC values and FA values of both side of the spinal cord were not significantly different. After injury, the ADC values of the injured spinal cord increased and FA values decreased comparing with that of the prenjured spinal cord. Four weeks after injury, the ADC and FA values of both side of the spinal cord were significantly different in the control group, but were not significantly different in the scaffold group and stem cell group. Conclusion DTI can provide useful information of spinal cord injury and regeneration in experimental spinal cord injury.
出处
《中国医学影像技术》
CSCD
北大核心
2005年第12期1869-1872,共4页
Chinese Journal of Medical Imaging Technology
关键词
脊髓损伤
神经干细胞
移植
扩散张量成像
磁共振成像
Spinal cord injury
Neural stem cells
Transplantation
Diffusion tensor imaging
Magnetic resonance imaging
