Abstract:

Objective To investigate the efficacy of diffusion tensor tractography (DTT) in study of changes of cerebral white matter fiber after cerebral blast injury. Methods Cerebral blast was conducted in 30 rabbits, and routine MRI and diffusion tensor imaging (DTI) were performed after injury. DTI was adjusted with Tensor software of Functool2, and cerebral white matter fiber of region of interest (ROI) was reconstructed on the basis of fractional anisotropy images. The cerebral histopathological changes were observed, and contrast analysis was carried out with findings from DTT. Results After blast, 17 rabbits died, and the other 13 survived, among which 2 survived for more than 72 h. There were 4 types of cerebral white matter abnormality, which were color abnormality of ornamental code (n=2), deficiency/breakage+displacement (n=8), rarity+deficiency/breakage (n=6) and color abnormality of ornamental code+deficiency/breakage+displacement (n=14). Pathological examination indicated there was capillary break, capillary endothelial injury and hemorrhage, nerve cell and colloid cell degeneration and necrosis, nerve myelin sheath loss and formation of axon bulb. Conclusion DTT may clearly and directly illustrate the injury of cerebral white matter fiber, especially for the small abnormal cerebral white matter fiber, and more complicated change of cerebral white matter fiber may lead to shorter duration of survival.

Key words: blast injury, diffusion tensor tracking, magnetic resonance imaging, cerebral white matter fiber