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Background and Purpose Secondary degeneration of fiber tract at motor pathway below in-farct foci and functional recovery after stroke has been well demonstrated,but the role of that above foci remains unclear.The aim of this study was to identify the longitudinal change of motor fibers above stroke lesion and its role in motor recovery after acute subcortical infarction.Methods Diffusion tensor imaging (DTI) and Fugl-Meyer (FM) scale were conducted 1,4,and 12 weeks (W) after an acute subcortical infarct,and in a healthy control group (n =22,respectively).Correlations between changes in diffusion parameters of motor fiber determined by tract-based spatial statistics combined with region of interest analysis and changes in FM scores were analyzed.Re-sults Axial diffusivity (AD) and mean diffusivity (MD) in the whole ipsilesional motor pathway declined sharply at W1 after stroke.After while the fractional anisotropy (FA) decreased,radial diffusivity (RD) and MD in-creased in the motor pathway above and below the infarcted lesion,at the same time AD progressively increased and relatively stable above and below the infarct respectively from W4 to W12 after stroke (P < 0.05,family-wise er-ror corrected).The changes of AD in the ipsilesional fiber tract of primary motor area positively correlated with the changes of FM scores (rs =0.514,P =0.014).Conclusions These results suggest secondary fiber changes a-bove and below stroke foci have different pattern and axonal plasticity above stroke foci may promote motor recovery after subcortical infarction.