Affiliations: Department of Physical Medicine and Rehabilitation,
School of Medicine, Yeungnam University, Republic of Korea | Department of Neurology, College of Medicine, Yeungnam
University, Republic of Korea | Department of Neurosurgery, School of Medicine, Ajou
University, Republic of Korea
Note: [] Corresponding author: Sung Ho Jang, Department of Physical
Medicine and Rehabilitation, School of Medicine, Yeungnam University 317-1,
Daemyungdong, Namku, Taegu, 705-717, Republic of Korea. Tel.: +82 053 620 3269;
Fax: +82 53 625 3508; E-mail: [email protected]
Abstract: Purpose: We investigated the motor recovery mechanism of a stroke
patient using functional MRI (fMRI) and diffusion tensor image tractography
(DTT). Methods: A 60 year-old woman with right corona radiata infarct
presented with complete paralysis of the left upper extremity. The motor
function of the affected upper extremity recovered slowly for 6 months to a
point of nearly normal function. The motor function of the patient was
evaluated by fMRI and DTT at 6 months from the onset. FMRI was performed at
1.5 T with timed hand grasp-release movements. DTT was performed using 1.5 T
with a synergy-L Sensitivity Encoding head coil. Three dimensional
reconstructions of the fiber tracts were obtained with FA < 0.3, angle
> 45° as termination criteria. Results: The contralateral primary sensorimotor cortex (SM1)
was activated during both affected (left) and unaffected hand movements. DTT
showed that the tracts originated from either SM1; the tracts then descended
along the known pathway of the corticospinal tract, with the exception that the
tract of the affected (right) hemisphere descended along the posterior portion
of the infarcted corona radiata. Conclusions: It seems that the motor function of the affected
upper extremity was reorganized to the posterior portion of the infarcted
corona radiata. This finding may reflect functional reorganization of the motor
pathway following corticospinal tract damage. This appears to be one motor
recovery mechanism of subcortical infarct.
