A Preliminary Study On The Value Of MRI IVIM-DWI In The Diagnosis Of Renal Tumors

Objective:To study and analyze the clinical value of intravoxel incoherent motion?IVIM?in the differential diagnosis and classification of renal tumors.Methods:According to the postoperative pathological results,26 patients with renal tumor were divided into three groups:smooth muscle lipoma group?n=5?,clear cell carcinoma group?n=16?and clear cell carcinoma group?n=16?.Routine double renal MRI plain scan,enhanced examination and IVIM examination were used to examine 26 patients with renal tumor.Non-clear cell carcinoma group?n=5?.The healthy kidneys were used in the control group?n=26?.The corresponding IVIM parameters were drawn in two different ways,and the difference between the lesion value and the control value was obtained by subtracting the lesion value from the control value.The parameters obtained by the two methods and their differences,the parameters between the four groups and their differences were compared.The diagnostic efficacy and optimal threshold of the parameters and differences for renal angiomyolipoma and clear cell carcinoma were calculated by using the working characteristic curve of the subjects.Results:There is a significant correlation between the values obtained by the two ROI mapping methods.There was no significant difference in mean value and integral ADC value,mean value f difference and integral slow-ADC value among different groups.There was significant difference in slow-ADC value between smooth muscle lipoma group and ccRCC group?p<0.005?,and there was significant difference between smooth muscle lipoma group and fast-ADC group?p<0.05?.There was significant difference between control group and ccRCC group?p<0.005?.There were significant differences in mean value,integral ADC difference and mean slow-ADC difference between smooth muscle lipoma group and ccRCC group,ccRCC group and non-ccRCC group?p<0.005?.There was no significant difference between lipoma group and non-ccRCC group?p>0.005?,but there was significant difference in mean fast-ADC between lipoma group and non-ccRCC group?p<0.005?.There was significant difference in the difference of fast-ADC between control group and ccRCC group?p<0.005?.There was significant difference between control group and ccRCC group,smooth muscle lipoma group and ccRCC group,ccRCC group and non-ccRCC carcinoma group?p<0.005?.The area under the curve of slow-ADC value of renal smooth muscle lipoma was the largest?AUC=0.943?and had significant significance?p<0.005?.The best diagnostic threshold was 0.925×10^-3mm²/s,the sensitivity was 100%,and the specificity was 90.5%.The area under the curve of ADC difference was the largest?AUC=0.900?by calculating the time mean value of renal clear cell carcinoma,and it was significant?p<0.005?.The best diagnostic threshold was-0.05×10^-3mm²/s,the sensitivity was 81.3%,and the specificity was 100%.Conclusion:The parameter values and parameter differences of IVIM-DWI technique have different research and application value in the differential diagnosis and classification of renal tumors,and some of the parameters have good diagnostic performance in this respect.The results of ROI sketched by mean method are more reliable and have research significance than the whole method.It is basically feasible to use the difference of each parameter for research and even clinical application.