BACKGROUND Nonalcoholic fatty liver disease(NAFLD) is currently the outstanding cause of chronic liver disease in children and adolescents, especially in overweight and obese groups. Liver biopsy is the reference stan...BACKGROUND Nonalcoholic fatty liver disease(NAFLD) is currently the outstanding cause of chronic liver disease in children and adolescents, especially in overweight and obese groups. Liver biopsy is the reference standard to diagnose NAFLD but invasive, thus it is not the best choice in clinical diagnosis and follow-up.Magnetic resonance(MR) is widely used in clinical trials to noninvasively quantify liver fat content in adults and children in foreign countries. While currently, it is rarely used in Chinese children and adolescents. We postulated that quantifying hepatic steatosis by MR could be extended to children and adolescents in China.AIM To investigate the accuracy of MR imaging(MRI) in quantifying liver fat with MR spectroscopy(MRS) as a reference. A secondary goal was to assess the prevalence of NAFLD in overweight and obese Chinese children and adolescents.METHODSThere were 86 children and adolescents enrolled in this study, including 65 overweight and obese children and 21 healthy children. The participants underwent MRI and MRS. MRI and MRS were performed using multi-echo Dixon and HISTO sequences, respectively, to calculate hepatic proton density fat fraction(PDFF). Hepatic steatosis was diagnosed using MRS-PDFF > 5% as the threshold. Spearman's analysis was used to evaluate the correlation between MRI and MRS. The agreement between these two methods was assessed by BlandAltman analysis.RESULTS The MRI-PDFF in the MRS region of interest and the entire liver was 9.9% ±10.3% with a range of 0.3%-39.9%, and 10.6% ± 9.4% with a range of 1.9%-38.9%,respectively. The MRS-PDFF was 9.1% ± 10.0%, with a range of 0.5%-37.8%. The incidence of hepatic steatosis detected by MRS-PDFF was 46.5%(40/86) of all participants, all of whom belonged to the overweight and obese group.Spearman's analysis indicated an excellent correlation between multi-echo Dixon and MRS(r > 0.9, P < 0.01). Bland-Altman analysis also demonstrated a good agreement between these two methods.CONCLUSION Multi-echo Dixon shows an excellent correlation and agreement with MRS in quantifying liver fat content and could be a potential tool to detect hepatic steatosis in Chinese children and adolescents.展开更多
BACKGROUND Liver fat accumulation is associated with increased cholesterol synthesis and hypersecretion of biliary cholesterol,which may be related to the development of cholelithiasis.AIM To investigate whether liver...BACKGROUND Liver fat accumulation is associated with increased cholesterol synthesis and hypersecretion of biliary cholesterol,which may be related to the development of cholelithiasis.AIM To investigate whether liver fat accumulation measured by high-speed T2-corrected multi-echo magnetic resonance spectroscopy(MRS)is a risk factor for cholelithiasis.METHODS Forty patients with cholelithiasis and thirty-one healthy controls were retrospectively enrolled.The participants underwent high-speed T2-corrected multi-echo single-voxel MRS of the liver at a 3T MR scanner.The proton density fat fraction(PDFF)and R2 value were calculated.Serum parameters and waist circumference(WC)were recorded.Spearman’s correlation analysis was used to analyze the relationship between PDFF,R2,and WC values.Multivariate logistic regression analysis was carried out to determine the significant predictors of the risk of cholelithiasis.Receiver operating characteristic curve(ROC)analysis was used to evaluate the discriminative performance of significant predictors.RESULTS Patients with cholelithiasis had higher PDFF,R2,and WC values compared with healthy controls(5.8%±4.2%vs 3.3%±2.4%,P=0.001;50.4±24.8/s vs 38.3±8.8/s,P=0.034;85.3±9.0 cm vs 81.0±6.9 cm,P=0.030;respectively).Liver iron concentration extrapolated from R2 values was significantly higher in the cholelithiasis group(2.21±2.17 mg/g dry tissue vs 1.22±0.49 mg/g dry tissue,P=0.034)than in the healthy group.PDFF was positively correlated with WC(r=0.502,P<0.001)and R2(r=0.425,P<0.001).Multivariate logistic regression analysis showed that only PDFF was an independent risk factor for cholelithiasis(odds ratio=1.79,95%CI:1.22-2.62,P=0.003).ROC analysis showed that the area under the curve of PDFF was 0.723 for discriminating cholelithiasis from healthy controls,with a sensitivity of 55.0%and specificity of 83.9%when the cut-off value of PDFF was 4.4%.CONCLUSION PDFF derived from high speed T2-corrected multi-echo MRS can predict the risk of cholelithiasis.展开更多
基金Supported by Shenzhen Science Technology Research and Development Fund from Shenzhen Science Technology and Innovation Commission,Shenzhen,Guangdong,China,No.JCYJ20160429174706491 and No.CXZZ20150529144041624
文摘BACKGROUND Nonalcoholic fatty liver disease(NAFLD) is currently the outstanding cause of chronic liver disease in children and adolescents, especially in overweight and obese groups. Liver biopsy is the reference standard to diagnose NAFLD but invasive, thus it is not the best choice in clinical diagnosis and follow-up.Magnetic resonance(MR) is widely used in clinical trials to noninvasively quantify liver fat content in adults and children in foreign countries. While currently, it is rarely used in Chinese children and adolescents. We postulated that quantifying hepatic steatosis by MR could be extended to children and adolescents in China.AIM To investigate the accuracy of MR imaging(MRI) in quantifying liver fat with MR spectroscopy(MRS) as a reference. A secondary goal was to assess the prevalence of NAFLD in overweight and obese Chinese children and adolescents.METHODSThere were 86 children and adolescents enrolled in this study, including 65 overweight and obese children and 21 healthy children. The participants underwent MRI and MRS. MRI and MRS were performed using multi-echo Dixon and HISTO sequences, respectively, to calculate hepatic proton density fat fraction(PDFF). Hepatic steatosis was diagnosed using MRS-PDFF > 5% as the threshold. Spearman's analysis was used to evaluate the correlation between MRI and MRS. The agreement between these two methods was assessed by BlandAltman analysis.RESULTS The MRI-PDFF in the MRS region of interest and the entire liver was 9.9% ±10.3% with a range of 0.3%-39.9%, and 10.6% ± 9.4% with a range of 1.9%-38.9%,respectively. The MRS-PDFF was 9.1% ± 10.0%, with a range of 0.5%-37.8%. The incidence of hepatic steatosis detected by MRS-PDFF was 46.5%(40/86) of all participants, all of whom belonged to the overweight and obese group.Spearman's analysis indicated an excellent correlation between multi-echo Dixon and MRS(r > 0.9, P < 0.01). Bland-Altman analysis also demonstrated a good agreement between these two methods.CONCLUSION Multi-echo Dixon shows an excellent correlation and agreement with MRS in quantifying liver fat content and could be a potential tool to detect hepatic steatosis in Chinese children and adolescents.
文摘BACKGROUND Liver fat accumulation is associated with increased cholesterol synthesis and hypersecretion of biliary cholesterol,which may be related to the development of cholelithiasis.AIM To investigate whether liver fat accumulation measured by high-speed T2-corrected multi-echo magnetic resonance spectroscopy(MRS)is a risk factor for cholelithiasis.METHODS Forty patients with cholelithiasis and thirty-one healthy controls were retrospectively enrolled.The participants underwent high-speed T2-corrected multi-echo single-voxel MRS of the liver at a 3T MR scanner.The proton density fat fraction(PDFF)and R2 value were calculated.Serum parameters and waist circumference(WC)were recorded.Spearman’s correlation analysis was used to analyze the relationship between PDFF,R2,and WC values.Multivariate logistic regression analysis was carried out to determine the significant predictors of the risk of cholelithiasis.Receiver operating characteristic curve(ROC)analysis was used to evaluate the discriminative performance of significant predictors.RESULTS Patients with cholelithiasis had higher PDFF,R2,and WC values compared with healthy controls(5.8%±4.2%vs 3.3%±2.4%,P=0.001;50.4±24.8/s vs 38.3±8.8/s,P=0.034;85.3±9.0 cm vs 81.0±6.9 cm,P=0.030;respectively).Liver iron concentration extrapolated from R2 values was significantly higher in the cholelithiasis group(2.21±2.17 mg/g dry tissue vs 1.22±0.49 mg/g dry tissue,P=0.034)than in the healthy group.PDFF was positively correlated with WC(r=0.502,P<0.001)and R2(r=0.425,P<0.001).Multivariate logistic regression analysis showed that only PDFF was an independent risk factor for cholelithiasis(odds ratio=1.79,95%CI:1.22-2.62,P=0.003).ROC analysis showed that the area under the curve of PDFF was 0.723 for discriminating cholelithiasis from healthy controls,with a sensitivity of 55.0%and specificity of 83.9%when the cut-off value of PDFF was 4.4%.CONCLUSION PDFF derived from high speed T2-corrected multi-echo MRS can predict the risk of cholelithiasis.
