A 51-year-old man showed hemiplegia on his right side after a traumatic brain injury (TBI). On initial brain computed tomography (CT) scan, an acute subdural hemorrhage in the right cerebral convexity and severe degrees of midline shifting and subfalcine herniation to the left side were evident. On follow-up brain magnetic resonance imaging (MRI), there were multiple microhemorrhages in the left parietal and occipital subcortical regions. To explain the occurrence of right hemiplegia after brain damage which dominantly on the right side of brain, we used diffusion tensor imaging (DTI) to reconstruct the corticospinal tract (CST), which showed nearly complete injury on the left CST. We also performed motor-evoked potentials, and stimulation of left motor cortex evoked no response on both sides of upper extremity. We report a case of patient with hemiplegia after TBI and elucidation of the case by DTI rather than CT and MRI.
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To compare diffusion tensor tractography (DTT) and motor evoked potentials (MEPs) for estimation of clinical status in patients in the subacute stage of stroke.
Patients with hemiplegia due to stroke who were evaluated using both DTT and MEPs between May 2012 and April 2015 were recruited. Clinical assessments investigated upper extremity motor and functional status. Motor status was evaluated using Medical Research Council grading and the Fugl-Meyer Assessment of upper limb and hand (FMA-U and FMA-H). Functional status was measured using the Modified Barthel Index (MBI). Patients were classified into subgroups according to DTT findings, MEP presence, fractional anisotropy (FA) value, FA ratio (rFA), and central motor conduction time (CMCT). Correlations of clinical assessments with DTT parameters and MEPs were estimated.
Fifty-five patients with hemiplegia were recruited. In motor assessments (FMA-U), MEPs had the highest sensitivity and negative predictive value (NPV) as well as the second highest specificity and positive predictive value (PPV). CMCT showed the highest specificity and PPV. Regarding functional status (MBI), FA showed the highest sensitivity and NPV, whereas CMCT had the highest specificity and PPV. Correlation analysis showed that the resting motor threshold (RMT) ratio was strongly associated with motor status of the upper limb, and MEP parameters were not associated with MBI.
DTT and MEPs could be suitable complementary modalities for analyzing the motor and functional status of patients in the subacute stage of stroke. The RMT ratio was strongly correlated with motor status.
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To investigate whether early stage diffusion tensor tractography (DTT) values predict motor function at 3 months after onset in supratentorial stroke patients with severe motor involvement.
A retrospective study design was used to analyze medical records and neuroimaging data of 49 supratentorial stroke patients with severe motor involvement. Diffusion tensor imaging was assessed within 3 weeks after stroke in all patients. Three-dimensional tractography of the ipsilateral corticospinal tract (CST) was performed using the fiber assignment of the continuous tracking algorithm. The two-step DTT analysis was used. The first step was classification according to ipsilateral CST visualization. The second step was a quantitative analysis of the visible-CST group parameters. Motor function was assessed at 2 weeks and at 3 months after stroke. Comparative and correlation analyses were performed between DTT-derived measures and motor assessment scores.
Motor function of the upper extremity at 3 months after stroke was significantly higher in the visible-CST group than that in the nonvisible-CST group (p<0.05). Early stage fractional anisotropy was of DTT correlated significantly with upper extremity motor function at 3 months after stroke in the visible-CST group (p<0.05).
These results demonstrate that early DTT-derived measures predict motor recovery in the upper extremity at 3 months after onset in supratentorial stroke patients with severe motor involvement.
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