Motor function reorganization lateral to congenital brain lesion: a functional MRI study.

Objective: The object of this study was to demonstrate the reorganization of the affected hand motor function lateral to the congenital brain lesion in a patient using functional MRI (fMRI).

Methods: Twelve normal control subjects and a 23-year-old man with a congenital brain lesion including the precentral knob were evaluated. FMRI was performed using the blood oxygen level-dependent technique at 1.5-T system with timed hand grasp-lease motor tasks.

Results: The contralateral primary sensorimotor cortex centered on the precentral knob was activated during hand movements of the right side of the patient and of control subjects. However, only the lateral area of the lesion was activated during left hand movements of the patient.

Conclusions: It seems that the motor function of the left hand was reorganized into the lateral area of the lesion in this patient. This finding may reflect a cortical reorganization of the motor area.