Corticospinal Tract Change in the Unaffected Hemisphere at the Early Stage of Intracerebral Hemorrhage: A Diffusion Tensor Tractography Study

Abstract
Objectives: Contribution by the unaffected hemisphere is one of the motor recovery mechanisms following stroke. We attempted to investigate changes in the corticospinal tract (CST) in the unaffected hemisphere at the early stage in patients with intracerebral hemorrhage (ICH), using diffusion tensor tractography (DTT). Subjects and Methods: Fifty-three consecutive hemiparetic patients and 40 age- and sex-matched control subjects were enrolled. DTT was performed using a 1.5-tesla system at the early stage of ICH (7–28 days after onset). We measured the fiber number, fractional anisotropy and apparent diffusion coefficient of CST tractography in the unaffected hemisphere, and assessed the motor function of the affected extremities. Results: The fiber number of the CST in the unaffected hemisphere of the patient group was higher than that of the control group (p = 0.000). In contrast, the fractional anisotropy value was lower than that of the control group (p = 0.018). However, there were no significant differences in the apparent diffusion coefficient values between the 2 groups (p = 0.654). Conclusions: We demonstrated that the CST in the unaffected hemisphere was changed at the early stage in patients with ICH, using DTT.