Study Of MR Diffusion-weighted Imaging In Hepatofibrosis

First part Study of liver fibrosis and its correlation with liverand spleen DWI-ADC valuesPurposeTo explore liver and spleen DWI (diffusion-weighted imaging, DWI) imaging ADC values(apparent diffusion coefficient, ADC) in hepatic fibrosis, and its law and reason. To discusses therelationship between the ADC values in liver and spleen and the degree of liver fibrosis.Methods and MaterialsA total of 15 volunteers,39 patients who had liver fibrosis in this study. They were scannedusing GE 1.5 Tesla unit in 8 channel body of the phased front circle with b values of 200、400、600、800、1000 s/mm2, all with b = 0 s/mm2as reference, the computer processing getcorresponding ADC images. They measured in the right hepatic lobe and spleen and obtain acorresponding ADC values. The case group and control group all use of liver fibrosis fiberdegree S classification method. Under the installment S ADC values between groups ofcompares the single factor analysis of variance, two comparison between two groups such asvariance together with LSD-t test, not neat using Tamhane ’T2 test. The correlation analysisbetween hepatic fibrosis and the right liver lobe and spleen ADC values used Spearmancorrelation testing.Result15 cases of normal control group were S0 period. Cases group in S1 were 5 cases, 7 casesof S2, 9 cases of S3 period, 18 cases in S4 period. They were statistically significant differencesbetween liver fibrosis S staging and liver and spleen ADC values (p < 0.05). The correlationanalysis study show that, with the increase of fibrosis staging, hepatic fibrosis and liver ADCvalues were negative correlation, hepatic fibrosis and spleen ADC values with the S2 periodonly above fibrosis has significant correlation.Conclusion①With the increase of b values, whether the normal group or fibrosis group ADC valuesare gradually decreases. Under the same b value, ADCs which in liver fibrosis group of liveralways lower than normal liver. And the change of the spleen ADC values is, with the increase of value b, normal group and the spleen ADC values is a mild decline. And for fibrosis group, isdown significantly faster than normal group. In the same b value, the spleen’s ADCs, which thefibrosis group was lower than normal group.②Under the same b value, they were statisticallysignificant difference between the liver ADCs, spleen ADCs and liver fibrosis stage in each twogroups.③The correlation between liver fibrosis S stage and the liver ADCs were negativelycorrelated.④The correlation between above the liver fibrosis stage S2 and the spleen ADCswere negatively correlated. spleen ADCsPurposeTo explore the relationship between the ratio of liver and spleen ADC values (LiverADCs/Spleen ADCs) and liver fibrosis in magnetic resonance imaging DWI, and analyzes thereasons. To discusses this method of assessment the severity of ability in hepatic fibrosis.Methods and MaterialsUsing the same operation method and b values (choose b values in200,400,600,800,1000s/mm2) scan the same research object to get DWI, and measured on theimages to get the right hepatic lobe and spleen ADC values after the computer processing, tocalculate the ratio of liver and spleen ADC values(Liver ADCs/Spleen ADCs). Using spearmancorrelation testing to check out the correlation between liver fibrosis stage and liverADCs/spleen ADCs. And using the ROC curves to evaluate ability about liver ADCs/spleenADCs to assess of liver fibrosis stages, and calculated its sensitivity and specificity.ResultIt was no significant correlation between the ratio of liver and spleen ADCs and liverfibrosis in S0 and S1 period (r were: 0.536, 0.491, p > 0.05), and negative correlation with theS2-S4 period (r, were:-0.681, 0.828, and 0.385, p < 0.05). It was the strongest correlation in b =800s/mm2, and the evaluation was better than other group (S2 or greater AUC was 0.842，sensitivity was 0.819，specificity was 0.947；S3 or greater AUC was 0.995，sensitivity was 0.857，specificity was 0.991).Conclusion①It was negatively correlated between the ratio of liver and spleen and liver fibrosis ofabove S2 period.②The spleen as the reference organs for the evaluation of liver fibrosis, inb=800s/mm2, was highest efficiency to evaluation of liver fibrosis.