Diffusion tensor imaging in detection of early Wallerian degeneration of the pyramidal tract after cerebral infarction

Objective To investigate the feasibility of using diffusion tensor imaging(DTI) for detection of early Wallerian degeneration of the pyramidal tract after cerebral infarction.Methods Total 23 patients with middle cerebral artery infarction were recruited.All cases were assessed using DTI within 14 days following stroke attack.Quantitative FA and MD were obtained in region of interest(ROI) in infarction regions,the posterior limb of the internal capsule(PLIC) and cerebral peduncle(CP) along the ipsilateral pyramidal tract(CST).The indices of FA and MD of the ipsilateral regions were compared with those of matched contralateral regions.Results FA of the ipsilateral CST began to decrease at the third day and FA showed decrease in all cases after 7 days following attack.FA values of the affected side were lower in the affected side than in the unaffected side(P0.05) and MD values were not different between two sides(P0.05).Conclusions DTI can detect Wallerian degeneration of CST as early as the 3 days after stroke attack.