Objective To investigate the diagnostic value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters for cognitive dysfunction in first-episode stroke,thereby providing reference for the early clinical assessment of the risk of cognitive dysfunction in stroke and formulation of intervention programs.Methods A total of 122 patients with first-episode stroke were enrolled and divided into occurrence group(n=53)and non-occurrence group(n=69)according to whether they had cognitive dysfunction.Additionally,53 patients with non-cerebrovascular cognitive dysfunction were selected as control group.All patients underwent DCE-MRI examination after admission.The 3 groups and patients with different degrees of cognitive dysfunction were compared for DCE-MRI parameters,including interstitium-to-plasma rate constant(Kep),volume transfer constant(Ktrans),volume fraction of extravascular extracellular space(Ve),and volume fraction of plasma(Vp).The correlations of DCE-MRI parameters with the degree of cognitive dysfunction were analyzed,along with their diagnostic value for cognitive dysfunction and evaluation value for the risk of cognitive dysfunction after first-episode stroke.Results Both occurrence group and non-occurrence group had higher levels of Ktrans,Ve and Vp than control group,and these parameters were higher in occurrence group than non-occurrence group(P<0.05).Ktrans,Ve and Vp of patients with different degrees of cognitive dysfunction differed significantly(P<0.05),and they were increased significantly with the aggravation of cognitive dysfunction.Ktrans,Ve and Vp were all positively correlated with the degree of cognitive dysfunction (P<0.05). The AUC for the combined diagnosis using Ktrans, Ve and Vp was 0.921, significantly higher than single index (P<0.05). The risks of cognitive dysfunction in first-episode stroke patients with higher levels of Ktrans, Ve and Vp were 3.077, 1.944 and 2.313 times of the low-level, respectively. Conclusion DCE-MRI can be used to diagnose cognitive dysfunction in first-episode stroke, providing reference for early clinical prediction of cognitive dysfunction after stroke.