Application Of Of Dynamic Contrast Enhanced-magnetic Resonance Imaging (DCE-NRI) In Gliomas

Objective:To explore the value of dynamic contrast enhanced-MRI(DCE-MRI)combined with histogram analysis based on the whole tumor in the grading of brain gliomas.Materials and methods:To retrospectively analyze 50 patients with gliomas undergoing DCE-MRI before surgery.Of the 50 patients,13 were low grade gliomas(LGGs)and 37 were high grade gliomas(HGGs).The pharmacokinetic parameters including the.volume transfer constant between the plasma and extravascular extracellular space(Ktrans),the flux rate constant(Kep),the extravascular extracellular space per unit volume of tissue(Ve)and the blood plasma volume per unit volume of tissue(Vp)of every patient were calculated using pharmacokinetic model.The whole solid portion of the lesion were drawn as VOI.And the histogram parameters,including mean,standard deviation(SD),kurtosis and skewness,were calculated.Comparisons of the histogram parameters of Ktrans,Kep.Ve and Vp between the high and low grade,and between WHO grade ? and ?,? and IV were conducted using an independent student's t test.Comparison of the Ki-67 index between the HGGs and LGGs was conducted using Mann-Whitney U test.Receiver operating characteristic(ROC)curve was constructed to determine the diagnostic efficacy of every histogram parameter in differentiating HGGs from LGGs,Comparison of Ktrans,Kep,Ve,Vp values and the Ki-67 index were analyzed using the Pearson correlation coefficient analysis.Results:All the four histogram parameters of Ktrans and Ve,SD and skewness values of Kep,mean and SD values of Vp were significantly different between HGGs and LGGs(P<0.05).With ROC analysis,all the parameters show high diagnostic efficiency in the differentiation between HGGs and LGGs,of which the SD of Ktrans has the highest accuracy.In addition,SD,kurtosis and skewness of Ktrans,kurtosis and skewness of Kep,and mean of Ve were significantly different between WHO grade II and ? gliomas(P<0.05).All the four histogram parameters of Ktrans and Ve and SD of Kep were significantly different between WHO grade ? and IV gliomas(P<0.05).Ki-67 index of HGGs are higher than that of LGGs(P<0.05).Significant positive correlations were observed between Ktrans,Ve,VP values and the Ki-67 index(r=0.346,P=0.014;r=0.335,P=0.017;r=0.323,P=0.022,respectively).Conclusion:DCE-MRI combined with histogram analysis based on the whole tumor have an important clinical value in the grading of gliomas.