Can Zhao1, Jia-Sheng Rao1, Xiao-Jiao Pei2, Jian-Feng Lei3, Zhan-Jing Wang3, Wen Zhao4, Rui-Han Wei1, Zhao-Yang Yang4, Xiao-Guang Li5. 1. Beijing Key Laboratory for Biomaterials and Neural Regeneration, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China. 2. Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China; Department of Radiology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100043, China. 3. Medical Experiment and Test Center, Capital Medical University, Beijing 100069, China. 4. Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China. 5. Beijing Key Laboratory for Biomaterials and Neural Regeneration, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China; Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China. Electronic address: bhbmeuniversity@gmail.com.
Abstract
PURPOSE: Adequate evaluation of spinal cord parenchyma and accurate identification of injury range are considered two premises for the research and treatment of chronic spinal cord injury (SCI). Diffusion tensor imaging (DTI) provides information about water diffusion in spinal cord, and thus makes it possible to realize these premises. METHOD: In this study, we conducted magnetic resonance imaging (MRI) for Wistar rats 84days after spinal cord contusion. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) from different positions of the injured cord were collected, analyzed, and compared with the histological results and locomotor outcomes. Moreover, we performed fiber tractography, and examined the difference in cavity percentage obtained respectively via conventional MRI, DTI and histology. RESULTS: Results showed that the chronic SCI rats had the largest changes of all DTI metrics at the epicenter; the farther away from the epicenter, the smaller the variation. FA, AD and RD were all influenced by SCI in a greater space range than MD. The good consistency of FA values and histological results in specific regions evidenced FA's capability of reflecting Wallerian degeneration after SCI. DTI metrics at the epicenter in ventral funiculus also showed a close correlation with the BBB scores. Additionally, supported by the histological results, DTI enables a more accurate measurement of cavity percentage compared to the conventional MRI. CONCLUSION: DTI parameters might comprehensively reflect the post-SCI pathological status of spinal cord parenchyma at the epicenter and distal parts during the chronic stage, while showing good consistency with locomotor performance. DTI combined with tractography could intuitively display the distribution of spared fibers after SCI and accurately provide information such as cavity area. This may shed light on the research and treatment of chronic SCI.
PURPOSE: Adequate evaluation of spinal cord parenchyma and accurate identification of injury range are considered two premises for the research and treatment of chronic spinal cord injury (SCI). Diffusion tensor imaging (DTI) provides information about water diffusion in spinal cord, and thus makes it possible to realize these premises. METHOD: In this study, we conducted magnetic resonance imaging (MRI) for Wistar rats 84days after spinal cord contusion. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) from different positions of the injured cord were collected, analyzed, and compared with the histological results and locomotor outcomes. Moreover, we performed fiber tractography, and examined the difference in cavity percentage obtained respectively via conventional MRI, DTI and histology. RESULTS: Results showed that the chronic SCI rats had the largest changes of all DTI metrics at the epicenter; the farther away from the epicenter, the smaller the variation. FA, AD and RD were all influenced by SCI in a greater space range than MD. The good consistency of FA values and histological results in specific regions evidenced FA's capability of reflecting Wallerian degeneration after SCI. DTI metrics at the epicenter in ventral funiculus also showed a close correlation with the BBB scores. Additionally, supported by the histological results, DTI enables a more accurate measurement of cavity percentage compared to the conventional MRI. CONCLUSION: DTI parameters might comprehensively reflect the post-SCI pathological status of spinal cord parenchyma at the epicenter and distal parts during the chronic stage, while showing good consistency with locomotor performance. DTI combined with tractography could intuitively display the distribution of spared fibers after SCI and accurately provide information such as cavity area. This may shed light on the research and treatment of chronic SCI.
Authors: Adriana-Natalia Murgoci; Ladislav Baciak; Veronika Cubinkova; Tomas Smolek; Tomas Tvrdik; Ivo Juranek; Jozef Kafka; Dasa Cizkova Journal: Neurochem Res Date: 2019-05-04 Impact factor: 3.996
Authors: Ryckie G Wade; Steven F Tanner; Irvin Teh; John P Ridgway; David Shelley; Brian Chaka; James J Rankine; Gustav Andersson; Mikael Wiberg; Grainne Bourke Journal: Front Surg Date: 2020-04-16