The Correlation of Motor Impairment and Fractional Anisotropy in Diffusion Tensor Imaging in Post-stroke Hemiplegic Patients

ABSTRACT

OBJECTIVE: Diffusion tensor imaging (DTI) fully characterizes water molecule mobility, allowing an exploration of fiber tract integrity and orientation in the human brain. The purpose of this study was to investigate the correlation between motor impairment and the changes of fractional anisotropy (FA) in the internal capsule in post-stroke hemiplegic patients. METHOD: Six normal subjects and 19 post-stroke hemiplegic patients who had a lesion in the internal capsule were included in this study. DTI was performed with a 3.0 Tesla MR at the mean interval of 28.2 days after stroke. Motor impairment was assessed with the Motricity Index and Trunk Control Test at the time of the imaging study. FA was measured in anterior limb and posterior limb of internal capsule. RESULTS: FA reduced significantly in the affected region compared with the other unaffected region in patients and normal region in controls. FA in the affected posterior limb of the internal capsule was correlated with the Motricity Index score of the affected upper limb (r=0.642, p<0.05). CONCLUSION: DTI can be helpful to evaluate motor impairment of the upper limb in post-stroke hemiplegic patients.