AIM:To investigate perfusion change in contrastenhanced ultrasonography(CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model.METHODS:New Zealand white rabbits(3-4 kg) underwent bile duct...AIM:To investigate perfusion change in contrastenhanced ultrasonography(CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model.METHODS:New Zealand white rabbits(3-4 kg) underwent bile duct ligation to form a biliary obstruction model.We performed liver CEUS and laboratory tests on the day before the operation(day 0) and every 7 postoperative days until the rabbits were sacrificed.After CEUS,signal intensity of liver parenchyma with a time-intensity curve was analyzed.Perfusion parameters were automatically calculated from regionof-interests,including peak signal intensity,mean transit time,area under the curve and time to peak.Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice.Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis.The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated.RESULTS:From the nine rabbits,histological grades of liver fibrosis were grade 1 in one rabbit,grade 2 and 3 in three rabbits each,and grade 4 in two rabbits.Among the four CEUS parameters,only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades(OR =1.392,95%CI:1.114-1.741,P =0.004).The difference in peak signal intensity between day 0 and the last dayalso demonstrated an association with liver fibrosis(OR =1.191,95%CI:0.999-1.419,P =0.051).The other parameters tested,including mean transit time,area under the curve,and time to peak,showed no significant correlation with liver fibrosis grades.CONCLUSION:This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.展开更多
AIM: To evaluate the possibility of treatment effect monitoring using hepatic fat quantification magnetic resonance(MR) in pediatric nonalcoholic steatohepatitis(NASH).METHODS: We retrospectively reviewed the medical ...AIM: To evaluate the possibility of treatment effect monitoring using hepatic fat quantification magnetic resonance(MR) in pediatric nonalcoholic steatohepatitis(NASH).METHODS: We retrospectively reviewed the medical records of patients who received educational recommendations and vitamin E for NASH and underwent hepatic fat quantification MR from 2011 to 2013.Hepatic fat fraction(%) was measured using dual- and triple-echo gradient-recalled-echo sequences at 3T.The compliant and non-compliant groups were compared clinically,biochemically,and radiologically.RESULTS: Twenty seven patients(M:F = 24:3; mean age: 12 ± 2.3 years) were included(compliant group = 22,non-compliant = 5).None of the baseline findings differed between the 2 groups,except for triglyceride level(compliant vs non-compliant,167.7 mg/d L vs 74.2 mg/d L,P = 0.001).In the compliant group,high-density lipoprotein increased and all other parameters decreased after 1-year follow-up.However,there were various changes in the non-compliant group.Dualecho fat fraction(-19.2% vs 4.6,P < 0.001),tripleecho fat fraction(-13.4% vs 3.5,P < 0.001),alanine aminotransferase(-110.7 IU/L vs-10.6 IU/L,P = 0.047),total cholesterol(-18.1 mg/d L vs 3.8 mg/d L,P = 0.016),and triglyceride levels(-61.3 mg/d L vs 11.2 mg/d L,P = 0.013) were significantly decreased only in the compliant group.The change in body mass index and dual-echo fat fraction showed a positive correlation(ρ = 0.418,P = 0.030).CONCLUSION: Hepatic fat quantification MR can be a non-invasive,quantitative and useful tool for monitoring treatment effects in pediatric NASH.展开更多
Background and Aims:Visceral obesity is a risk factor for nonalcoholic fatty liver disease(NAFLD).We investigated sex-specific optimal cutoff values for visceral fat area(VFA)associated with lean and overweight/obese ...Background and Aims:Visceral obesity is a risk factor for nonalcoholic fatty liver disease(NAFLD).We investigated sex-specific optimal cutoff values for visceral fat area(VFA)associated with lean and overweight/obese NAFLD in an Asian population.Methods:This retrospective study includ-ed 678 potential living liver donors(mean age,30.8±9.4 years;434 men and 244 women)who had undergone ab-dominal computed tomography(CT)imaging and liver bi-opsy between November 2016 and October 2017.VFA was measured using single-slice abdominal CT.NAFLD was eval-uated by liver biopsy(≥5%hepatic steatosis).Receiver op-erating characteristic curve analysis was used to determine cutoff values for VFA associated with lean(body mass index[BMI]<23 kg/m2)and overweight/obese(BMI≥23 kg/m2)NAFLD.Results:Area under the curve(AUC)values with 95%confidence intervals(CI)for VFA were 0.82(95%CI,0.75-0.88)for lean and 0.74(95%CI,0.69-0.79)for over-weight/obese men with NAFLD.The AUC values were 0.67(95%CI,0.58-0.75)for lean and 0.71(95%CI,0.62-0.80)for overweight/obese women with NAFLD.The cutoff values for VFA associated with lean NAFLD were 50.2 cm2 in men and 40.5 cm2 in women.The optimal cutoff values for VFA associated with overweight/obese NAFLD were 100.6 cm2 in men and 68.0 cm2 in women.Conclusions:Sex-specific cutoff values for VFA may be useful for identifying subjects at risk of lean and overweight/obese NAFLD.展开更多
基金Supported by Faculty Research Grant of Yonsei University College of Medicine for 2013,No.6-2013-0040
文摘AIM:To investigate perfusion change in contrastenhanced ultrasonography(CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model.METHODS:New Zealand white rabbits(3-4 kg) underwent bile duct ligation to form a biliary obstruction model.We performed liver CEUS and laboratory tests on the day before the operation(day 0) and every 7 postoperative days until the rabbits were sacrificed.After CEUS,signal intensity of liver parenchyma with a time-intensity curve was analyzed.Perfusion parameters were automatically calculated from regionof-interests,including peak signal intensity,mean transit time,area under the curve and time to peak.Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice.Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis.The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated.RESULTS:From the nine rabbits,histological grades of liver fibrosis were grade 1 in one rabbit,grade 2 and 3 in three rabbits each,and grade 4 in two rabbits.Among the four CEUS parameters,only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades(OR =1.392,95%CI:1.114-1.741,P =0.004).The difference in peak signal intensity between day 0 and the last dayalso demonstrated an association with liver fibrosis(OR =1.191,95%CI:0.999-1.419,P =0.051).The other parameters tested,including mean transit time,area under the curve,and time to peak,showed no significant correlation with liver fibrosis grades.CONCLUSION:This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.
基金Supported by A new faculty research seed money grant of Yonsei University College of Medicine for 2013(8-2013-0028)
文摘AIM: To evaluate the possibility of treatment effect monitoring using hepatic fat quantification magnetic resonance(MR) in pediatric nonalcoholic steatohepatitis(NASH).METHODS: We retrospectively reviewed the medical records of patients who received educational recommendations and vitamin E for NASH and underwent hepatic fat quantification MR from 2011 to 2013.Hepatic fat fraction(%) was measured using dual- and triple-echo gradient-recalled-echo sequences at 3T.The compliant and non-compliant groups were compared clinically,biochemically,and radiologically.RESULTS: Twenty seven patients(M:F = 24:3; mean age: 12 ± 2.3 years) were included(compliant group = 22,non-compliant = 5).None of the baseline findings differed between the 2 groups,except for triglyceride level(compliant vs non-compliant,167.7 mg/d L vs 74.2 mg/d L,P = 0.001).In the compliant group,high-density lipoprotein increased and all other parameters decreased after 1-year follow-up.However,there were various changes in the non-compliant group.Dualecho fat fraction(-19.2% vs 4.6,P < 0.001),tripleecho fat fraction(-13.4% vs 3.5,P < 0.001),alanine aminotransferase(-110.7 IU/L vs-10.6 IU/L,P = 0.047),total cholesterol(-18.1 mg/d L vs 3.8 mg/d L,P = 0.016),and triglyceride levels(-61.3 mg/d L vs 11.2 mg/d L,P = 0.013) were significantly decreased only in the compliant group.The change in body mass index and dual-echo fat fraction showed a positive correlation(ρ = 0.418,P = 0.030).CONCLUSION: Hepatic fat quantification MR can be a non-invasive,quantitative and useful tool for monitoring treatment effects in pediatric NASH.
文摘Background and Aims:Visceral obesity is a risk factor for nonalcoholic fatty liver disease(NAFLD).We investigated sex-specific optimal cutoff values for visceral fat area(VFA)associated with lean and overweight/obese NAFLD in an Asian population.Methods:This retrospective study includ-ed 678 potential living liver donors(mean age,30.8±9.4 years;434 men and 244 women)who had undergone ab-dominal computed tomography(CT)imaging and liver bi-opsy between November 2016 and October 2017.VFA was measured using single-slice abdominal CT.NAFLD was eval-uated by liver biopsy(≥5%hepatic steatosis).Receiver op-erating characteristic curve analysis was used to determine cutoff values for VFA associated with lean(body mass index[BMI]<23 kg/m2)and overweight/obese(BMI≥23 kg/m2)NAFLD.Results:Area under the curve(AUC)values with 95%confidence intervals(CI)for VFA were 0.82(95%CI,0.75-0.88)for lean and 0.74(95%CI,0.69-0.79)for over-weight/obese men with NAFLD.The AUC values were 0.67(95%CI,0.58-0.75)for lean and 0.71(95%CI,0.62-0.80)for overweight/obese women with NAFLD.The cutoff values for VFA associated with lean NAFLD were 50.2 cm2 in men and 40.5 cm2 in women.The optimal cutoff values for VFA associated with overweight/obese NAFLD were 100.6 cm2 in men and 68.0 cm2 in women.Conclusions:Sex-specific cutoff values for VFA may be useful for identifying subjects at risk of lean and overweight/obese NAFLD.