ABSTRACT
Objective To explore the relationship between upper-extremity motor functional outcomes and the brain white matter integrity with diffusion tensor imaging (DTI). Methods Seventeen patients with moderate upper-extremity impairment were enrolled and were assessed with the Wolf Motor Function Test (WMFT) and the upper limb portion of the Fugl-Meyer (FM) motor assessment battery. The structural integrity of the posterior limb of the internal capsule (PLIC) was assessed through examining the fractional anisotropy (FA) asymmetry between the ipsilesional and contralesional PLIC. Linear regression analysis was performed with FA asymmetry and the upper limb FM scores, WMFT asymmetry, log WMFT and grip strength asymmetry. Results FA asymmetry was strongly related to FM score (R~2=0.655, P＜0.002), WMFT asymmetry score (R~2=0.649, P＜0.002), lg WMFT (R~2＜0.636, P=0.002) and the grip asymmetry score (R~2 =0.414, P=0.02), respectively. Conclusion The clinical motor function is closely related to the white matter integrity of the internal capsule in patients 3-9 months after stroke. DTI assessment of the relative degree of white matter integrity in the internal capsule may be an useful approach to interpret motor deficits in patients with upper limb motor dysfunction and predict the motor function recovery.