抄録
[Purpose] We attempted to demonstrate the changes in cortical activation with motor recovery in hemiparetic patients who showed mild weakness at onset and excellent recovery, using functional MRI (fMRI). [Methods] Six patients (mean age 49.83 ± 8.75) with corona radiata infarct were recruited for this study. The motricity index for the upper extremity, the Medical Research Council classification for finger extensors, and the modified Brunnstrom classification were used to determine the motor function of the affected upper limb. fMRI was performed twice, after onset and after recovery, at 1.5 T in parallel with hand grasp-release movements at a fixed rate. The laterality index was calculated from the fMRI to assess fMRI the relative activity of the ipsilateral versus the contralateral primary sensorimotor cortex. [Results] There were significant improvements in motor function tests and the laterality index between the first and second fMRI. However, the interval changes of motor function tests were not significantly correlated with those of the laterality index of the affected hemisphere. [Conclusion] The patients who showed mild weakness at onset and excellent recovery had cortical activation that changed towards contralateral motor cortex activation from bilateral motor cortex activation during the recovery phase. This finding has important clinical implications with regard to the motor recovery mechanism and the scientific rehabilitation of stroke patients.
