Evaluation of the Relationship between Extremity Motor Function Impairment and Cortical Spinal Tract Involvement in Cerebral Ischemic Stroke with Diffusion Tensor Imaging (DTI)

Objective:To evaluate the relationship between the impairment severity of cortical spinal tract (CST) and muscle strength in acute ischemic stroke patients.Methods:DTI was respectively performed in 9 patients with acute cerebral ischemic stroke and a control group of 9 volunteers using a GE Signa Excite MR scanner.dTV.Ⅱ software was used for fiber tracking.Fractional anisotropy (FA) maps and 3D tractography of bilateral CST of all patients and volunteers were created.Brunstorm criteria were used to evaluate the hand motor function.Results:The FA values of the white matter in infarction area were significant lower than those of their counterparts in the normal hemisphere (paired test,t=4.570,P0.001).Correlation between the changes of FA values in the infarction area and the impairment of relative muscle strength of the hand (spearmen correlation,r=0.888,P0.05) was noted,and DTI showed that the corresponding CST was compressed,shifted and partly torn.Conclution:In acute cerebral ischemic stroke,the impairment severity of CST of the hand was corre-latively related to its changes in muscle strength,therefore,DTI was indicated to serve as a predictive means for the effect of rehabilitation treatment and disease prognosis.Moreover,3D fiber tractographic maps displayed 'real' and more stereo images of the pyramidal tracts.