Evaluation of the Relationship between Neuromotor Outcome and Early Wallerian Degeneration of Corticospinal Tract after Cerebral Infarction Using Diffusion Tensor MR Imaging

Purpose:To evaluate the relationship between neuromotor outcome and early Wallerian degeneration of corticospinal tract(CST) after cerebral infarction using diffusion tensor MR imaging(DTI).Methods:A total of 16 patients with middle cerebral artery infarction within 14 days after attack were studied with DTI.Quantitative FA and MD,obtained by placing regions of interest(ROI) at the ipsilateral cerebral peduncle,upper and lower slices of the pons,were compared with matched contralateral regions.The neurological examinations,together with NIHSS,MI and mRS were performed in all cases at the time of DTI and 3 months after cerebral infarction.Results: There was no significant difference in the DTI indices between the affected and unaffected sides at 1 week after cerebral infarction.And there was significant difference in the FA but not the MD at the 2 weeks after cerebral infarction.There were no significant correlations between the rFA of the CSTs and the NIHSS,MI at the second week after cerebral infarction.There were significant negative correlations between the rFA of the CSTs and the NIHSS,mRS and there were significant positive correlation between the rFA of the CSTs and the MI at the 3 months after cerebral infarction.Conclusion: The long-term neuromotor outcome could be predicted by the changes of FA at the second week after infarction attack.