Diffusion Tensor Imaging Study Of Acute Cerebral Infarction In The Basal Ganglia And Corona Radiate At3.0T MRI

Objective:To explore the application value in prognosis evaluation of MR diffusion tensor imaging (DTI) and Diffusion tensor tractography(DTT) in acute ischemic cerebral infarction.Methods:Forty-one patients,including29males and12females, aged34-83years old, mean58±2.4years old, with the acute cerebral infarction from Affiliated Hospital of Zunyi Medical College participated in DTI studies and conducted on a3.0T MR imaging scanner, of which32cases reinspect DTI at3weeks after the initial inspection. All cases were followed-up office visit3months later, test muscle strength of ipsilateral, and then, divided41cases into three groups according to ipsilateral muscle recovery, Group A:fully restored (restored to5); Group B:partially restored (recovery but less than5); Group C:no recovery (had no change or reduce). Analysis the image differences between conventional MRI and DTI.ROIs were selected both lesion area and corresponding part of the contralateral area used for measure the average FA and ADC values no less than three times.Calculate the relative value of ADC and FA--rFA and rADC(relative value=lesion area values/contralateral values) and its reduce range--dFA and dADC,(reduce range=contralateral value-lesion area value). Reconstruct and classificate the corticospinal tract(CST):Grade1:CST completed; Grade2:CST partial disrupted, but not more than1/2of the contralateral; Grade3:CST interrupt greater than1/2of the contralateral; Grade4:CST completely disrupted.Results:(1) DWI and ADC maps of11patients showed the lesions range larger than conventional MRI.(2) The ADC and FA values were reduced in varying degrees, the difference was statistically significant(P<0.001). It showed a negative correlation between the ADC、FA, as well as their relative value(rADC and rFA),and the course of disease in different degree,.while as a positively correlation between dFA and illness course (P<0.05).(3) Initial MR scan of each group, ADC、rADC and rFA were compared and analyzed for statistically significant differences (P<0.05).(4) ADC values of all reinspection cases were increased in varying degrees; FA values of twenty-nine cases were decreased, the remaining three cases were increased. The change range of rFA analyzed for statistically significant differences in each group.(5) The CST grade of first scan showed a negative relationship with ipsilateral muscle recovery level(P<0.05). It showed a significant negative correlation between CST grade of reinspection and ipsilateral muscle recovery level(P<0.001).However, the CST variation trend (decrease or no significant change) was positively correlated with ipsilateral muscle recovery level (P<0.05).Conclusion:(1)DTI was able to show some lesions that can not be displayed by the conventional MRI.(2)There were correlations between ADC、rADC、rFA and ipsilateral muscle strength recovery.(3) It was a significant correlation between rFA decrease extent of3weeks after first scan and muscle strength recovery.(4)The integrity of corticospinal tract was closely related to the level of muscle strength recovery.