3.0T MR IVIM-DWI Quantitative Index In Evaluating The Differentiation Of Hepatocellular Carcinoma

Objective: To explore the feasibility of Diffusion Weighted Imaging(DWI)and intravoxel incoherent motion diffusion-weighted imaging(IVIM-DWI)in grading of the hepatocellular carcinoma(HCC).Methods: 54 cases of hepatocellular cancer patients confirmed by pathology in our hospital in January 2016-2016 period December.For all patients with a 3.0T GE Signa HDx scanner for routine MR scan、mutiple b values DWI examination and dynamic enhancement scan.Measure these parameters by checking ADW 4.6 workstation,including the apparent diffusion coefficient(ADC values)、the true diffusion coefficient(D value),perfusion-related diffusion coefficient(D* value)and perfusion fraction(f value).According to the HCC phase enhancement signal characteristics in arterial phase and portal venous,which are divided into three types of reinforcement.All HCC were divided into low differentiation group and high differentiation group according to the Edmondson-Steiner grading.The ADC value、D value,D* value f value were separately calculated.Comparison between groups was conducted with nonparametric test(Mann-Whitney U).The ADC value and D value were correlated with the degree of HCC differentiation,and the ADC value was low correlated with the degree of differentiation of HCC(r=0.418,P<0.05).The D value was significantly correlated with the differentiation degree of HCC(r=0.616,P<0.05).The comparison of three types of reinforcement using X2 test.while receiver operating characteristic(ROC)analysis was used to make the comparison of the predictive values in preoperatively grading HCC among ADC value and D value.when P< 0.05 the difference was considered to be statistically significant.Result: There were 22 cases in the high differentiation group,the other 32 cases in the low differentiation group.44 cases were man;10 cases were women.There were 14 cases in the left lobe of the liver;There were 40 cases in the right lobe of the liver.There was no significant difference in maximal tumor diameter between the high and low differentiation group(P>0.05).The mean ADC、D、D* and f values of the high-differentiation group were(1.27±0.19)×10-3mm2/s、(1.19±0.14)×10-3mm2/s、(43.26±9.07)×10-3mm2/s、(29.36±7.19)×10-3mm2/s respectively;while those values of the low-differentiation group were(1.11±0.17)×10-3mm2/s、(0.96±0.16)×10-3mm2/s、(47.91±12.01)×10-3mm2/s、(31.81±11.33)×10-3mm2/s respectively.Compared with the low-differentiation group,the ADC value and D value of the high-differentiation group were increased,D* value and f value were decreased.The ADC value and D value have statistically significant differences between the two groups(P <0.05);The D* value and f value have no statistically significant difference existed between the two groups(P> 0.05).The areas under the ROC curve of ADC values and D values were 0.74 and 0.86 respectively.According to maximum Youden index,the optimal threshold value for diagnosis was 1.16×10-3mm2/s 、 1.09×10-3mm2/s respectively,the corresponding sensitivity and specificity were 77.3%、63.6% and 90.9%、79.1%.Of 54 HCC type Ⅰwas seen in 31,type Ⅱin 18 and type Ⅲ in 5.TypeⅠwas mainly seen in low-differentiation HCC group,TypeⅡwas mainly seen in high-differentiation HCC group.The enhancement pattern between the two groups were statistically significant(P<0.05).Conclusions : ADC value and D value have an important reference value for evaluating the differentiation of HCC.D value has higher test efficiency than ADC value in distinguish the differentiation of HCC.D value has higher sensitivity and specificity.ADC value and D value were correlated with the degree of HCC differentiation,and the D value was higher relativity than the ADC value.The dynamic enhancement type of HCC can reflect the differentiation and the blood supply of tumor in a certain degree.