Abstract: Objective:To investigate the correlation of magnetic resonance diffusion tensor imaging(DTI) after diffuse axonal injury(DAI) with cognitive function at recovery stage.Methods:Eighteen patients with DAI(DAI group) were early examined using DTI,and the result of which was compared with that of 16 heathy volunteers(control group).DTI was processed using Track and MRIcron software,the fractional anisotropy(FA) and apparent diffusion coefficient(ADC) value were quantified from different regions of interest(ROI) area,and the FA and ADC value between DAI group and control group were compared.The DAI patients at recovery stagepost-injury (17.26±4.31) months were assessed using the cognition scale,the result of which was compared with that of control group with similar education.The contents of cognition scale included the digital back test of Wechsler adult intelligence scale(Hunan version),California speech learning scale,wired test and Stroop color-word test.The difference of the cognition function between two groups was compared.The correlation between DTI parameter and cognition scale score was analyzed using the Pearson linear correlation in DAI group.Results:At early stage of DAI,the FA value in all ROI areas in DAI group were significantly lower than that in control group(P<0.01),the ADC values of fasciculus uncinatus and fasciculi longitudinalis inferior in DAI group were higher than those in control group(P<0.05),and the difference of the ADC in other ROI area was not statistically significant(P>0.05).At recovery stage,the scores of the digital back test,California speech learning scale,short-term free and clue recall scales in DAI group decreased compared with control group(P<0.01),and the scores of the wired test,and Stroop color-word test 1,2 and 3 in DAI group increased compared with control group(P<0.05 to P<0.01).The FA value in uncinate fasciculus,anterior corona radiata,superior longitudinal fasciculus and inferior longitudinal fasciculus was significantly correlated with the total scores of working memory and executive function scale in DAI group(P<0.01 and P<0.05),but the ADC value in ROIs was not significantly correlated with the total scores of working memory and executive function scale in DAI group(P>0.05).Conclusions:Early magnetic resonance DTI detection in DAI patients is helpful to predict different types of cognitive dysfunction during the recovery,which can provide a theoretical basis for the early diagnosis and treatment of patients.