The Application Research Of Functional Magnetic Resonance Imaging IVIM And DKI In The Grading Diagnosis Of Renal Carcinoma

Objective:To evaluate the diagnostic value of intravoxel incoherent motion（IVIM）and diffusion kurtosis imaging（DKI）techniques in the grade of clear cell renal cell carcinoma（CCRCC）.Methods:To retrospectively analyze the imaging data of 35 patients with CCRCC confirmed by postoperative pathology.According to Fuhrman’s pathological grade,A total of 21 patients with pathological grades I and II were classified as low-grade group,and a total of 14 patients with pathological grades III and IV were classified as high-grade group.Before the operation,patients undergo routine MRI,IVIM,and DKI examinations.To import the images of the patient’s IVIM and DKI into the post-processing software provided by Philips to calculate the corresponding pseudo-color image,and then obtain the relevant values of parameters（D,D*,f,MK,MD values）by sketching the area of interest.The parameters that conform to the normal distribution were compared with the independent sample t-test to compare the differences between the two groups,and the parameters of the non-normal distribution were compared with the Mann Whitney U test.Spearman correlation analysis was used to analyze the correlation between IVIM and DKI and pathological grade of CCRCC.The ROC curve was used to evaluate the diagnostic efficacy of IVIM and DKI related values of parameters in distinguishing the grades of high and low CCRCC.Results:1.The difference of IVIM and DKI parameter values between the high and low-grade CCRCC group:The D and MD values of the group of high-grade CCRCC were significantly lower than that of the low-grade group（P<0.01）;the MK values of the group of the high-grade CCRCC was significantly higher than the low-grade group（P<0.01）.However,the D*and f values were not significantly different between the high and low-level groups（P>0.05）.2.The related analysis between related parameter values of IVIM and DKI and CCRCC pathological grade:The D and MD values were significantly negatively correlated with the pathological grade of CCRCC（rs=-0.676,-0.699,P=0.000）;The MK values were significantly positively correlated with pathological grade（rs=0.768,P=0.000）.3.The diagnostic efficiency of IVIM and DKI related parameters to distinguish high and low-grade CCRCC:The AUC of D,MD,and MK values that diagnose low and high CCRCC grades were 0.898,0.912,0.952;the optimal diagnostic thresholds were 1.02×10^-3mm²/s,2.39×10^-3mm²/s,0.73;sensitivity were 85.7%,76.2%,85.7%;specificity were 78.6%,92.9%,100%（all P=0.000）.Conclusion:1.Diffusion related parameters（D,MD,MK）can be used to accurately distinguish high and low-grade CCRCC,which can provide important value for clinical diagnosis and treatment;2.D and MD values are significantly negatively correlated with CCRCC pathological grading,and MK values are significantly positively correlated with pathological grading;3.Compared with IVIM,DKI is better to diagnose the grade of CCRCC,and MK value is the most promising parameter to distinguish the grade of high and low-grade CCRCC.