Objective:To establish and verify a nomogram model based on MRI liver imaging reporting and data system (LI-RADS) features for predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC) following the Milan criteria.Methods:A retrospective analysis was conducted on data from 118 HCC patients (121 lesions) confirmed by pathology from June 2016 to June 2022 at the Third Affiliated Hospital of Soochow University. Forty-seven HCCs were diagnosed as MVI-positive and 74 HCCs as MVI-negative. The data was randomly divided into the training set (83 patients with 84 HCCs, including 31 MVI-positive and 53 MVI-negative HCCs) and the test set (35 patients with 37 HCCs, including 16 MVI-positive and 21 MVI-negative HCCs) using cross-validation method. HCC imaging features were evaluated based on LI-RADS (version 2018). In the training set, the χ 2 test was used to compare the differences in LI-RADS features between the MVI-positive group and the MVI-negative group. The logistic regression analysis was conducted to identify independent risk factors for predicting MVI-positive and to construct the nomogram model. The receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the performance and clinical benefits of the nomogram model in predicting MVI tumors. Results:There were statistically significant differences between the MVI-positive group and the MVI-negative group in terms of tumor size, tumor margin, mosaic architecture, and corona enhancement ( P<0.05). Multivariate logistic analysis results showed that HCC maximum diameter>3 cm (OR=1.427, 95%CI 1.314-12.227, P=0.009), nonsmooth tumor margin (OR=3.167, 95%CI 1.227-461.232, P=0.041), mosaic architecture (OR=1.769, 95%CI 1.812-61.434, P=0.022), and corona enhancement (OR=4.015, 95%CI 3.327-836.384, P=0.011) were independent risk factors for predicting MVI-positive tumors. Based on the independent predictors, the constructed nomogram model demonstrated an area under the ROC curve of 0.863 (95%CI 0.768-0.947) and 0.887 (95%CI 0.804-0.987) in the training and test sets for predicting MVI tumors, respectively. DCA showed that the curve of the nomogram model was consistently above the treat-all and treat-none strategies across all reasonable threshold probabilities in the training set, indicating that patients could obtain clinical benefits from the model. Conclusions:The preoperative nomogram model based on MRI LI-RADS features can effectively predict MVI in HCC following the Milan criteria, which could benefit the patients.

Objective:To explore the value of proton density fat fraction(PDFF) based on histogram analysis for quantification hepatic steatosis and fibrosis in rabbit model and the interference of hepatic fibrosis to the evaluation of hepatic steatosis with PDFF.Methods:From March to November 2020, 135 New Zealand white rabbits were randomly divided into control group ( n=30) and experimental group ( n=105) using a random number table. The volume ratio of CCl 4 and olive oil was 1∶1 to prepare 50% CCl 4 oil solution, and experimental rabbits were subcutaneously injected with the oil solution. An equal dose of normal saline was subcutaneously injected for control group rabbits. At the end of the 4 th, 8 th, and 12 th week, 35 in the experimental group and 10 rabbits in the control group were randomly selected to conduct the mDixon-Quant scanning, and histogram analysis of PDFF was analyzed including volume, mean, median, standard deviation, 25 th, 50 th, 75 th, 90 th quantile, skewness, kurtosis, entropy and inhomogeneity. After the examination, the rabbits were sacrificed and the liver percentage of steatosis (PSH) and fibrosis (POF) were recorded by semi-quantitative analysis. Spearman correlation analysis was used to correlate PDFF with PSH and POF. Multiple linear regression analysis was used to determine independent PDFF histogram parameters for evaluating PSH and POF. A receiver operator characteristic (ROC) curve was used to assess the diagnostic accuracy of PDFF for discriminating mild from moderate-severe hepatic steatosis and mild from moderate-severe hepatic fibrosis with median of PSH or POF for dichotomy, and DeLong test was used to compare the area under the curve (AUC). With the correction of hepatic fibrosis, correlation coefficient and AUC were compared of PDFF for discrimination mild from moderate-severe hepatic steatosis. Results:The PDFF mean, median, standard deviation, 75 th, 90 th showed correlation with PSH ( r=0.558, 0.522, 0.319, 0.723, 0.646, -0.589, all P<0.05). The entropy and 75 th were independent parameters for evaluating PSH (β=2.347, -5.960, P=0.018, 0.001). The PDFF 75 th was the optimal parameter for discriminating mild from moderate-severe hepatic steatosis with AUC=0.915 ( P=0.001). The PDFF volume, mean, median, standard deviation, 75 th, 90 th, entropy showed correlation with POF ( r=0.355, 0.393, 0.376, 0.298, 0.485, 0.426, -0.681, all P<0.05). The entropy, standard deviation and volume (β=-11.041, 1.356, 0.190, P=0.001, 0.026, 0.016) were independent parameters for evaluation of hepatic fibrosis, and the entropy was the optimal parameter for hepatic fibrosis (AUC=0.771, P=0.001). The correlation between PSH and PDFF 75 th was less pronounced when fibrosis was present ( r=0.512, P=0.001) than when fibrosis was absent ( r=0.751, P=0.002). The PDFF 75 th showed a significant difference in discriminating mild hepatic steatosis from moderate-severe hepatic steatosis after correction of POF (AUC=0.895, 0.950, Z=2.970, P=0.025). Conclusions:PDFF based on histogram analysis provided a noninvasive, accurate estimation of quantification for hepatic steatosis and fibrosis. Hepatic fibrosis reduced the correlation between hepatic steatosis and PDFF and the presence of hepatic fibrosis can confound the quantification of hepatic steatosis with PDFF.

Objective:To explore the value of MR elastography (MRE) and shear wave elastography (SWE) for staging liver fibrosis in a rabbit model.Methods:From March to November 2020, 200 healthy New Zealand white rabbits were randomly divided into control group ( n=40) and liver fibrosis group ( n=160) by random number table method. The volume ratio of CCl 4 and olive oil was 1∶1 to prepare 50% CCl 4 oil solution, and the experimental rabbits in the liver fibrosis group were subcutaneously injected with 50% CCl 4 olive oil solution. It was injected once a week at the dose of 0.1 ml/kg in the first to third weeks, once a week at the dose of 0.2 ml/kg in the 4th to 6th weeks. The dose of 0.1 ml/kg was injected twice a week from week 7 to 16. The control group were subcutaneously injected with an equal dose of normal saline. At the end of the 4th, 8th, 12th, and 16th week, 40 and 10 animals in the liver fibrosis group and the control group were randomly selected by random number table method for MRE and SWE, respectively, to obtain the liver elastic stiffness (LS), which were recorded as LS MRE and LS SWE. After the examination, the experimental rabbits were sacrificed and liver tissue of rabbits were taken for histopathological Scheuer staging, and they were divided into F0-F4 groups. One-way ANOVA was used to evaluate the differences of LS MRE and LS SWE in different stages of liver fibrosis. Spearman correlation was used to analyze the correlation between LS and pathological stages. The receiver operating characteristic curve was used to evaluate the efficacy of LS MRE and LS SWE in diagnosing liver fibrosis staging, and the area under the curve (AUC) was compared using the Z test. Results:Totally 162 rabbits were included, which covered F0 ( n=38), F1 ( n=33), F2 ( n=35), F3 ( n=31) and F4 ( n=25). Significant differences of LS MRE and LS SWE values were found among different stages of liver fibrosis ( F=295.29, 102.40, both P<0.001). LS MRE, LS SWE were both positively correlated with liver fibrosis stage ( r=0.93, 0.81, both P<0.001). The AUC of LS MRE for diagnosing liver fibrosis stages ≥F1, ≥F2, ≥F3, and ≥F4 were 0.955, 0.967, 0.996, and 0.980, respectively; the AUC of LS SWE were 0.856, 0.880, 0.974, and 0.953, respectively. The AUC of liver fibrosis stage ≥ F1, ≥ F2 for LS MRE value were greater than LS SWE value ( Z=2.93, 3.29, P=0.003, 0.001), and the AUC of ≥F3, ≥F4 had no significant differences ( Z=1.58, 1.68, P=0.115, 0.093). Conclusion:Both MRE and SWE can accurately predict the stage of liver fibrosis in experimental rabbits, and MRE is better than SWE in diagnosing early liver fibrosis.

Objective:To compare the diagnostic efficacy of MR elastography (MRE), Gd-EOB-DTPA dynamic contrast-enhanced MRI (DCE-MRI) in early quantitative evaluation of liver fibrosis (LF) staging of experimental rabbits.Methods:From April to December 2019, 200 healthy rabbits were randomly divided into LF group ( n=160) and control group ( n=40). LF group were injected subcutaneously with 50% CCl 4 oil solution, while control group were injected with normal saline solution. The LF group ( n=40) and control group ( n=10) were randomly selected at the end of the 4th, 8th, 12th and 16th weeks respectively to undergo axial MRI scan including MRE and Gd-EOB-DTPA DCE-MRI. The quantitative parameter values were obtained, including liver stiffness (LS), volume transfer constant (K trans), reflux rate constant (K ep), volume fraction of extravascular extracellular space (V e) and volume fraction of plasma (V p). Histopathological LF staging was based on Scheuer staging. One-way ANOVA analysis was used to evaluate the differences of LS, K trans, K ep, V e and V p among different LF stages. The Spearman correlation analysis was used to evaluate the correlations between pathological LF staging and quantitative parameter values. The ROC curve was used to compare the diagnositic performance of all quantitative parameter values. Results:Among the final qualified 150 rabbits, there were 32 in F0, 32 in F1, 35 in F2, 30 in F3, 21 in F4. Significant differences of LS, K trans, K ep, V e and V p were found among different LF stages. There was correlation between LS, K trans, K ep and LF stages ( r=0.832, 0.730, -0.617, all P<0.001), respectively. However, no statistically correlation was found between V e, V p and LF stages ( r=-0.074, P=0.367; r=-0.078, P=0.342). The area under the ROC curve (AUCs) of LS were the greatest (0.920 for F0 vs F1-F4, 0.900 for F0 vs F1-F2, 0.945 for F0 vs F3-F4, 0.926 for F1-F2 vs F3-F4), while the AUCs of K trans were 0.897, 0.863, 0.942, 0.809, respectively. Conclusion:The early quantitative diagnostic efficacy for LF staging by MRE was superior to Gd-EOB-DTPA DCE-MRI in rabbits.

Objective To assess diagnostic performance of multi?parametric MRI including MR elastography (MRE), susceptibility?weighted imaging (SWI) and T1ρ imaging in detecting the early stage of liver fibrosis (LF). Methods Eighty healthy rabbits were randomly divided into LF group (n=60) and control group (n=20). The LF group (n=12) and control group (n=5) were randomly selected at the end of the 4th, 5th, 6th, 15th week after injection of 50% CCl4 oil solution, respectively. All rabbits underwent 3.0 T MRI scans and histopathological Scheuer staging. Differences between groups were examined using one?way analysis of variance with Dunnett's T3 test. Spearman correlation was used to analyze the correlation between liver stiffness (LS), liver?to?muscle SI ratio (SIR), T1ρ value in different LF stages. ROC curve analysis was used to assess the diagnostic performance. Results Fifty?five rabbits were included in our study, which covered F0 (n=14), F1 (n=11), F2 (n=10), F3 (n=9) and F4 (n=11). Significant differences of all characteristic values were found among different LF stages (P<0.05).There were significant differences in LS values between F0 and F2, F3, F4, respectively; F1 and F3, F4, respectively; F2 and F4; F3 and F4 (P<0.05). There were significant differences in SIR between F0 and F2, F3, F4, respectively; F1 and F2, F3, F4, respectively; F2 and F4 (P<0.05). T1ρ value showed significant differences between F0, F1, F2, F3 and F4, respectively (P<0.05). LS, SIR, and T1ρ values were correlated with LF stage (r=0.910, -0.808, 0.512, respectively, P<0.01). The area under curve (AUC) for LS value were greater than those for the other two methods (0.953 for≥F1, 0.949 for≥F2, 0.986 for≥F3, 0.979 for F4). The AUCs of the combination of MRE and SWI for detecting≥F1 was 0.965, for≥F2 was 0.983, for≥F3 was 0.991, and for F4 was 0.950. Combining all three MR methods showed the highest diagnostic performance for staging LF with AUCs of 0.969, 0.985, 0.996 and 1.000.Conclusion MRE is the most prominent MRI method, and combination of MRE and SWI show higher diagnostic performance than the others for staging LF; however, combining all three MR methods exhibits the most excellent diagnostic efficacy.

Objective: To assess diagnostic performance of multi-parametric MRI including MR elastography (MRE), susceptibility-weighted imaging (SWI) and T₁ρ imaging in detecting the early stage of liver fibrosis (LF). Methods: Eighty healthy rabbits were randomly divided into LF group (n=60) and control group (n=20). The LF group (n=12) and control group (n=5) were randomly selected at the end of the 4^th, 5^th, 6^th, 15^th week after injection of 50% CCl₄ oil solution, respectively. All rabbits underwent 3.0 T MRI scans and histopathological Scheuer staging. Differences between groups were examined using one-way analysis of variance with Dunnett's T3 test. Spearman correlation was used to analyze the correlation between liver stiffness (LS), liver-to-muscle SI ratio (SIR), T₁ρ value in different LF stages. ROC curve analysis was used to assess the diagnostic performance. Results: Fifty-five rabbits were included in our study, which covered F0 (n=14), F1 (n=11), F2 (n=10), F3 (n=9) and F4 (n=11). Significant differences of all characteristic values were found among different LF stages (P<0.05).There were significant differences in LS values between F0 and F2, F3, F4, respectively; F1 and F3, F4, respectively; F2 and F4; F3 and F4 (P<0.05). There were significant differences in SIR between F0 and F2, F3, F4, respectively; F1 and F2, F3, F4, respectively; F2 and F4 (P<0.05). T₁ρ value showed significant differences between F0, F1, F2, F3 and F4, respectively (P<0.05). LS, SIR, and T₁ρ values were correlated with LF stage (r=0.910, -0.808, 0.512, respectively, P<0.01). The area under curve (AUC) for LS value were greater than those for the other two methods (0.953 for≥F1, 0.949 for≥F2, 0.986 for≥F3, 0.979 for F4). The AUCs of the combination of MRE and SWI for detecting≥F1 was 0.965, for≥F2 was 0.983, for≥F3 was 0.991, and for F4 was 0.950. Combining all three MR methods showed the highest diagnostic performance for staging LF with AUCs of 0.969, 0.985, 0.996 and 1.000. Conclusion MRE is the most prominent MRI method, and combination of MRE and SWI show higher diagnostic performance than the others for staging LF; however, combining all three MR methods exhibits the most excellent diagnostic efficacy.

Objective To investigate the value of susceptibility weighted imaging (SWI) with T1ρimaging in staging of hepatic fibrosis(HF) in rabbits. Methods Eighty selected white rabbits from New Zealand were randomly divided into the HF group (n=60) and the control group (n=20). Rabbits in the HF group were injected subcutaneously with 50％CCl4 oil solution to establish HF model,and the normal control rabbits were injected with saline solution subcutaneously.The HF group(n=15) and control group(n=5) were randomly selected at the 4th, 5th, 6th and 10th week after injection, to undergo liver MR scan. The liver signal intensity (SI liver), the muscle signal intensity (SI muscle),liver-to-muscle SI ratios (SIR) and liver T1ρvalues were measured. Scheuer was adopted to stage the rabbits in HF. One-way analysis of variance was used to compare the differences between SIR and T1ρ values in different stages of HF pathological. Spearman correlation was used to analyze the correlation between SIR and T1ρ values in the different stage of HF pathological.The ROC were used to compare the efficacy between SIR and T1ρvalues in the diagnosis of HF pathological stage. Results Among the final qualified 68 rabbits in the study, 17 in F0 phase, 11 in F1 phase, 16 in F2 phase, 11 in F3 phase, and 13 in F4 phase. The SIR were (0.977 ± 0.013), (0.960 ± 0.015), (0.802 ± 0.026), (0.786 ± 0.022), (0.541 ± 0.116); T1ρ values were (22.301 ± 1.849), (24.034 ± 0.867), (25.374 ± 1.309),(25.364±1.945),(30.948±2.925) ms.There were statistically significant in SIR between F0 and F2,F0 and F3, F0 and F4, F1 and F2, F1 and F3, F1 and F4, F2 and F4, F3 and F4 (P<0.01). There were statistically significant in T1ρvalues between F0 and F1,F0 and F2,F0 and F3,F0 and F4,F1 and F2,F1 and F4,F2 and F4, F3 and F4(P<0.05). SIR were negatively correlated with HF staging while T1ρ values were positively. ROC showed that the AUC of the T1ρvalues was slightly larger than SIR in the F4 group(0.992>0.966),and the AUC of the SIR was greater than T1ρvalues in the other groups. Conclusion SWI and T1ρvalues can provide an important objective basis in staging of HF. Both of them have great clinical application prospects but SIR diagnostic efficiency is slightly better than that of T1ρvalues.

Objective To compare the diagnostic values of magnetic resonance elastography (MRE) and T1ρ imaging in staging hepatic fibrosis (HF) in a rabbit model.Methods The institutional animal care and use committee approved all experiments.Sixty healthy rabbits were divided into HF group (n=44) and control group (n=16).Each eight rabbits in the HF group and 4 rabbits in the control group were randomly selected at the 4th,5th,6th week and the remaining rabbits at the 10th week after subcutaneous injection with 0.1 ml 50％ CCl4 oily solution per kilogram of body respectively,to undergo liver MR scan including axial liver MRE and T1ρ imaging.The values of liver stiffness (LS) and T1ρ were measured.Masson trichrome staining of liver tissue was used.According to the Scheuer scoring system,rabbits were classified into F0 to F4 group based on the percentage of hepatic fibrosis.The difference of LS values and Tip values among stage F0 to F4 were compared by the one-way ANOVA analysis.The correlations between pathological staging and LS,T1ρ values were performed by the Spearman correlation analysis.ROC curve analysis was performed to compare the value of MRE with T1ρ imaging.Results Forty three rabbits were included,there were 10,8,8,8,9 rabbits in F0,F1,F2,F3 and F4 stage,respectively.LS values were (1.051±0.155),(1.335±0.235),(1.401±0.163),(2.001±0.499) and (2.981±0.714) kPa in F0,F1,F2,F3 and F4,respectively,while T1 p values were (23.20±4.02),(24.28±2.93),(25.40± 1.82),(24.69± 1.85) and (31.54±3.39) ms (all P＜0.05).The correlation of LS values with hepatic fibrosis staging measured on MRE was stronger than T19 values (r values were 0.916 and 0.608,all P＜0.01).Area under ROC curve of LS value for differentiating hepatic fibrosis stage were 0.938 to 0.989,while the areas of T1ρ were 0.771 to 0.954.Conclusion MR elastography is an accurate technique for quantitatively staging hepatic fibrosis and superior to T1ρ imaging.

Objective To assess the value of susceptibility-weighted imaging (SWI) in staging hepatic fibrosis (HF) in rabbits. Methods Sixty healthy rabbits were randomly divided into HF group (n=44), control group (n=16). Rabbits in the HF group and supplementary group were injected subcutaneously with 50%CCl4 oily solution to establish hepatic fibrosis model. On the basis of preliminary test, 8 rabbits in the HF group and 4 rabbits in the control group were selected randomly at the 4th, 5th, 6th, 10th week after CCL4 injection ,respectively , to undergo liver MR scan,including conventional axial T1WI, T2WI and axial SWI, DWI scan. All rabbits were sacrificed after MR scan and the tissue of liver were sampled for pathological test and hepatic fibrosis staging. Rabbits were classified into group F0, F1-2 and F3-4 based on pathological results. Liver signal intensity (SI), and liver-to-muscle SI ratio were measured on SWI images and ADC values were measured on DWI images correspondently. One-way ANOVA analysis was performed to compare difference in liver SI, liver-to-muscle SI ratio and ADC values among group F0 (no fibrosis), F1-2 (mild-moderate fibrosis) and F3-4 (severe fibrosis) . Spearman correlation analysis was performed to correlate pathological staging and liver SI, liver-to-muscle SI ratio and ADC values. Receiver operating characteristic (ROC) curve analysis was performed to compare the diagnostic performance of SWI and DWI for staging HF. Results Two and 5 rabbits in the HF group died at the 5th and the 6th week after CCL4 injection , respectively due to acute hepatic necrosis, hepatorrhexis and systemic failure. Seven rabbits in supplementary group were used as supplement. Of the 16 rabbits in the control group, 1 was excluded from the study due to liver fibrosis. Fifteen rabbits in group F0, sixteen rabbits in group F1-2 and sixteen rabbits in group F3-4 underwent MRI and were included into this study. Liver-to-muscle SI ratio in group F0, F1-2 and F3-4 were 0.973 ± 0.020, 0.880 ± 0.090 and 0.649 ± 0.140, respectively. Liver SI were 378 ± 45, 374 ± 19 and 317 ± 34. ADC values were (1.473 ± 0.320) × 10-3, (1.311 ± 0.310) × 10-3 and (0.942 ± 0.180) × 10-3mm2/s. There were statistically significant differences in liver SI, liver-to-muscle SI ratio and ADC values among group F0, F1-2 and F3-4 (F=46.571,15.803 and 15.317, P< 0.01). Liver-to-muscle SI ratio was highly negatively correlated with HF staging (r=-0.818,P<0.01), while liver SI and ADC values were moderately correlated with HF staging (r=-0.565,-0.630;P<0.01). Area under ROC curve (AUC) of liver-to-muscle SI ratio, liver SI and ADC value for differentiating hepatic fibrosis stage F0 and stage F1-4 were 0.916, 0.695 and 0.768, while the AUC for differentiating hepatic fibrosis stage F0-2 and stage F3-4 were 0.951, 0.904 and 0.900. Conclusion Liver-to-muscle SI ratio on SWI provide added diagnostic value and could be an useful parameter for staging hepatic fibrosis.

Objective To investigate balanced steady-state free precession with flow-sensitive dephasing magnetization preparation (FSD-bSSFP) in the assessment of arteries of foot in diabetic patients.Methods The lower-extremity peripheral arteries of 43 diabetic patients were evaluated by FSD-bSSFP no contrast MRA and contrast-enhanced MRA (CE-MRA)in. Two experienced observers assessed the image quality, degree of venous contaminated and visibility of pedal artery branches by FSD-bSSFP and CE-MRA respectively in consensus. The signal intensity( SI), signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the source images of both groups were measured and Wilcoxon and t tests were performed. Results The image score of FSD-bSSFP group was 2.7 ± 1.1 and CE-MRA was 2.6 ± 0.8, there was no statistical difference ( Z = 0. 134, P ＞ 0. 05 ). The image score of demonstration of the pedal artery branches and degree of venous contamination on FSD-bSSFP were 3.2 ± 0. 9 and 1.8 ± 0. 4 respectively which were superior to that of CE-MRA (2.5 ± 0.9 and 2.1 ± 0.8 respectively). Significant statistical difference existed between the two groups in demonstration of pedal artery branches ( Z = 5.246, P ＜ 0.05 ) and degree of venous contamination (Z =2.541 ,P ＜0.05). SNR of FSD-bSSFP was 148.6 ±26.7, CNR was 88.3 ± 19.0. SNR of CE-MRA was 148.5 ± 45.6, CNR was 121.0 ± 41.0. No statistical difference existed between SNR between two methods (t = 0.013, P ＞ 0.05 ). But CNR of CE-MRA was superior to that of FSD-bSSFP and significant statistical difference existed between these two methods ( t = 5.113, P ＜ 0.01 ). Conclusion FSD-bSSFP without contrast could be used in the evaluation of foot arteries in patients of renal dysfunction and diabetes.