Application Of IVIM-DWI Imaging Techniques For Diagnosis Of Focal Liver Lesions And LI-RADS Classification At 3 Tesla Magnetic Resonance

Objective:1.To evaluate the diagnostic contribution of IVIM-DWI imaging techniques to focal liver lesions(FLLs)at 3 Tesla magnetic resonance.2.To evaluate the diagnostic contribution of IVIM-DWI imaging techniques to liver benign and malignant lesions at 3 Tesla magnetic resonance.3.To evaluate the diagnostic contribution of IVIM-DWI imaging techniques to LI-RADS classification at 3 Tesla magnetic resonance.Materials and Methods:199 focal liver lesions(13 liver cysts,21hemangiomas,28 Cirrhosis nodules,80 hepatocellular carcinomas,50 hepatic metastases(48 hepatic primaliry Colon or rectum tumors,2 hepatic primaliry pancreas tumors),7 cholangiocarcinomas)of 59 patients undergoing Surgical pathology or MR check or confirmed by clinical follow-up results.Classified the lesions to benign and malignant:Benign lesions including hemangiomas,liver cysts,cirrhosis nodules;Malignant lesions including hepatocellular carcinomas,metastases,cholangiocarcinomas.Classified the lesions according to LI-RADS(v2014),30 LR-1(13 cysts,17 hemangiomas),47 LR-3(3 hemangiomas,25 Cirrhosis nodules,19 hepatocellular carcinoms,27 LR-4(1 hemangioma,3Cirrhosis nodules,23 hepatocellular carcinomas),20 LR-5(20 hepatocellular carcinoms).All the patients underwent conventional MR examinations and IVIM-DWI,using 10 b values(0,5,10,20,50,100,200,400,800,1200s/mm2).By the post-processing,measuremented the Standard ADC、Slow ADC、Fast ADC、F values.Analysised data as the following:①Analysised the data of Standard ADC、Slow ADC、Fast ADC、F values of FLLs with single factor analysis of variance,pairwise comparison.②Analysised the data of Standard ADC、Slow ADC、Fast ADC、F values of liver benign and malignant lesions with T test.③Analysised the data of Standard ADC、Slow ADC、Fast ADC、F values of LR-1、3、4、5 with single factor analysis of variance,pairwise comparison.All reported P values were declared to indicate a significant difference if less than 0.05.Results:1.The Standard ADC values of Focal liver lesions from high to low as follows:cysts、hemangiomas、Cirrhosis nodules、metastases、hepatocellular carcinomas、cholangiocarcinomas.The Standard ADC values of liver cysts and hemangiomas was obviously higher than that of other lesions with statistically significant.However,that was similar between hepatic cysts and hemangiomas.It also similar between cirrhosis nodulars and hepatocellular carcinomas,metastases,cholangiocarcinomas with no statistical difference.The Slow ADC values of Focal liver lesions from high to low as follows:cysts、metastases、hemangiomas、cholangiocarcinomas、hepatocellular carcinomas、Cirrhosis nodules.It was no significant statistical difference between the Slow ADC values of Metastases and cysts.The Slow ADC values of cysts was:(1.08±0.27)×10-3mm2/s,it was higher than that of Cirrhosis nodules and hepatocellular carcinomas with statistically significant.It was similar between hemangiomas、cholangiocarcinomas、hepatocellular carcinomas and cirrhosis nodulars with no statistical difference.F values of liver hemangiomas were obviously higher than that of other lesions,with statistically significant.That of cholangiocarcinomas were lower than that of cirrhosis nodulars、hepatocellular carcinomas and metastatic tumors with statistically significant differences.It was similar between cirrhosis Nodulars、metastases and hepatocellular carcinomas with no statistical difference.Fast ADC values of Focal liver lesions has no statistical difference.2.Standard ADC values of Benign lesions((1.63 + 0.72)×10-3mm2/s)were significantly higher than those of malignant lesions((1.00+0.36)×10-3mm2/s)with significant statistical difference.The values of Standard ADC、Slow ADC、Fast ADC、F of liver benign and malignant lesions has no obvious difference.3.Standard ADC values of LR-1 were higher than those of LR-3、LR-4、LR-5 with significant statistical difference.Those of 4 cases of hemangiomas which were Classffied to LR-3,4 lesions conformed to those of LR-1.Slow ADC values of LR-1 were higher than those of LR-3、LR-4 with significant statistical difference,however,similar to that of LR-5.The values of Standard ADC、Slow ADC、Fast ADC、F of LR-3,LR-4,LR-5 has no obvious difference.Conclusion:Standard ADC values of liver cysts and hemangiomas was obviously higher than that of other focal liver lesions,it was difficult to identify other focal liver lesions.Slow ADC values of hepatic primaliry Colon or rectum tumors were higher than that of cirrhosis nodulars and hepatocellular carcinomas,it has differential effects between them.Fast ADC and F values reflect the microvascular density of lesions,it has differential effects between F values of hemangiomas and cholangiocarcinomas,but it was difficult to identify other focal liver lesions.Standard ADC values have role to identify benign and malignant liver lesions,those of benign lesions were(1.63±0.72)×10-3mm2/s,those of malignant lesions were(1.00±0.36)×10-3mm2/s.It has no identification of values of Standard ADC,Fast ADC,and F of liver benign and malignant lesions.From the values between Standard of ADC,slow ADC,Fast ADC and F that obtained by IVIM-DWI imaging,we can see that Standard ADC values of LR-1 level and other levels had identification sense,it was help for diagnosis atypical hemangiomas as LR-1 combining with Standard ADC values.