Diffusion tensor imaging change in crus cerebri in striatocapsular infarction and correlation with upper extremity motor dysfunction.

PURPOSE: There is limited information about the secondary changes in the pyramidal tract after some specific types of deep brain infarction including striatocapsular infarction. The aims of the current study were to investigate diffusion changes in the crus cerebri in patients with striatocapsular infarction using diffusion tensor imaging (DTI), and analyze the relationship between such changes and upper extremity motor dysfunction. MATERIALS AND METHODS: Fifteen patients with acute onset of striatocapsular infarction and unilateral upper extremity motor dysfunction for the first time were studied prospectively. DTI was performed 2 weeks after disease onset, fractional anisotropy and mean diffusivity values of the bilateral crus cerebri were measured, the asymmetry indices of bilateral fractional anisotropy were calculated, and the relationship between the asymmetry index value and the Fugl-Meyer assessment score for the affected upper extremity function was evaluated. RESULTS: Two weeks after disease onset, the fractional anisotropy value of the affected crus cerebri was reduced significantly compared with that of the unaffected crus cerebri (0.69 vs. 0.77; p < 0.001); there was no significant difference between bilateral mean diffusivity values. After correction for infarct size (448.93 ± 227.67 mm(2)) there was a negative correlation between the asymmetry index value and the Fugl-Meyer assessment score of the affected upper extremity (r = -0.78, p = 0.001). CONCLUSIONS: DTI can detect the diffusion change in the crus cerebri in patients with striatocapsular infarction during the early stage of the disease and the integrity of the pyramidal tract in the crus cerebri is closely related to the motor function of the affected upper extremity.