Study Of Corticospinal Tract Integrity And Motor Function Recovery After Acute Cerebral Infarction Using Diffusion Tensor Imaging And Diffusion Tensor Tractography

Objective:To evaluate the integrity of corticospinal tract in patients with acute cerebral infarction using magnetic diffusion tensor imaging and diffusion tensor tractography,and to analyze the correlation between CST injury indicators and the motor function prognosis.Methods:From December 2021 to October 2022,32 patients hospitalized in the Department of Neurology of our hospital and clinically diagnosed with acute cerebral infarction were selected as the case group.All patients were the first onset,within 7 days of onset,unilateral lesions and all had different degrees of limb motor dysfunction.And 18 outpatient patients with age and gender were selected as healthy control groups.All subjects underwent DTI scans and traced the corticospinal tract template of the healthy control group through DTT.The CST fractional anisotropy of patients with cerebral infarction was measured,including FAipsilesional and FAcontralesional,and the FA ratio(r FA)and FA asymmetry(FAasy)were further calculated.The lesion map was drawn to measure the lesion volume,and the lesion area was superimposed with the CST template of the healthy control group to calculate the “CST damage value”.Stroke patients received a “wrist+hand” and upper limb motor function Fugl-Meyer Assessment within 7 days of onset,and followed up for 3 months(90±15days).The correlation between the FAipsilesional,r FA,FAasy,and CST damage value of patients with cerebral infarction and the FMA-WH and FMA-UE within 7 days and3 months was analyzed.According to the FMA-UE after 3 months,the case groups were divided into good prognosis group and poor prognosis group,and the differences in FAipsilesional,r FA,FAasy,and CST damage value between the two groups were compared.The ROC curve of CST injury indexes with statistically significant differences was drawn,and the efficacy of each CST injury index in predicting the prognosis of motor dysfunction in patients was analyzed.Results:1.FA of the ipsilesional CST in patients with acute cerebral infarction decreased significantly compared with the contralesional CST(t=-6.679,P<0.001).Compared with the healthy control group,the r FA of the case group was significantly reduced(t=-5.330,P<0.001),while the FAasy was significantly increased(t=5.210,P<0.001).2.There was no significant correlation between age and lesion volume and FMA-WH and FMA-UE within 7 days and 3 months(P>0.05)in patients with acute cerebral infarction.FAipsilesional,r FA,FAasy,and CST damage value were significantly correlated with FMAWH and FMA-UE within 7 days and 3 months in patients with acute cerebral infarction(P<0.05),and the correlation with FMA-WH was stronger.Other than that,FAipsilesional was positively correlated with FMA-WH(0),FMA-WH(3),FMA-UE(0)and FMA-UE(3),(r=0.451,r=0.383,r=0.554,r=0.520,P<0.05),r FA was positively correlated with FMAWH(0),FMA-WH(3),FMA-UE(0)and FMA-UE(3),(r=0.543,r=0.470,r=0.620,r=0.560,P<0.05).FAasy was negatively correlated with FMA-WH(0),FMA-WH(3),FMA-UE(0),FMA-UE(3),(r=-0.541,r=-0.470,r=-0.621,r=-0.562,P<0.05),CST damage value was negatively correlated with FMA-WH(0),FMA-WH(3),FMA-UE(0),FMA-UE(3),(r=-0.581,r=-0.547,r=-0.701,r=-0.651,P<0.05).3.There were significant differences in FAipsilesional,r FA,FAasy,and CST damage value in the poor prognosis group and the good prognosis group.Compared with the group of poor prognosis,FAipsilesional and r FA of the good prognosis group were increased(t=2.906,t=3.207,P<0.05),and FAasy and CST injury value were reduced(t=-3.267,t=-3.125,P<0.05).4.The area under of ROC Curve of FAipsilesional,r FA,FAasy,and CST damage value in patients with acute cerebral infarction were 0.818,0.801,0.801 and 0.758(P<0.05),respectively.Conclusion:The CST microstructural integrity of patients after acute cerebral infarction could be evaluated by magnetic resonance DTI and DTT,and the CST injury indicators derived from CST template could be used as a good predictor of upper limb motor dysfunction,especially wrist and hand.In patients with acute cerebral infarction,the value of ipsilesional CST FA decreased significantly within 7 days of onset.Higher FAipsilesional and r FA value indicate a better prognosis,and higher FAasy and CST damage value indicate a worse prognosis.The CST damage value has the highest efficacy in evaluating the prognosis of upper limb motor function after three months in patients with acute cerebral infarction,which may become an important reference index for early prediction of motor prognosis in patients with acute cerebral infarction.