Performance Of Magnetic Resonance Elastography Research Articles

Magnetic resonance elastography (MRE) outperforms acoustic force radiation impulse (ARFI) in predicting oesophageal varices in obese NAFLD cirrhosis.

Liver stiffness measurement (LSM) by transient elastography has been shown to underperform in high-risk varices (HRVs) prediction in obese non-alcoholic fatty liver disease (NAFLD) compensated cirrhosis (CC). LSM by magnetic resonance elastography (MRE) and acoustic force radiation impulse (ARFI) has been shown to be useful in prediction of oesophageal varices (EVs), but has limited evidence in obese NAFLD-CC. Obese patients with NAFLD-CC who underwent MRE and ARFI for LSM and endoscopy for screening of varices were enrolled. Performance of MRE and ARFI for predicting EVs or HRVs was evaluated using area under receiver operating characteristics (AUROC) curves and regression analyses were performed for predictor variables. One hundred eight patients [mean age 54.7 ± 9.6years, median BMI, 28.5 (26.4-30.0) kg/m2. 72.2% diabetics, 45.4% hypertensive] were enrolled. Fifty-two (48.1%) had no varices, while 29 (26.8%) and 27 (25%) had low-risk varices (LRVs) and HRVs, respectively. MRE-LSM was higher in patients with LRVs (p = 0.01) or HRVs (p = 0.001) against those without varices. ARFI-LSM did not differ significantly between those without and with LRVs or HRVs (p > 0.05 for all). There was a low correlation between ARFI-LSM and MRE-LSM in the overall cohort (r = 0.19). Only platelet count (PC) [0.98 (0.97-0.99)] and MRE-LSM [1.8 (1.26-2.79)] were predictors of HRVs. At a cut-off of 4.75, MRE showed a sensitivity of 96.3%. Model combining MRE-LSM with PC had a diagnostic AUROC of 0.77 and 0.76 for EVs and HRVs. In obese NAFLD-CC, MRE-LSM is significantly higher in patients with varices. MRE combined with PC predicts EVs and HRVs with better accuracy than ARFI.

A combination of non-invasive tests for the detection of significant fibrosis in patients with metabolic dysfunction-associated steatotic liver disease is not superior to magnetic resonance elastography alone.

The aims of the present study were to investigate a combination of magnetic resonance elastography (MRE) and vibration-controlled transient elastography (VCTE) or MRE and fibrosis score 4 (FIB-4) in the detection of significant fibrosis in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Between November 5, 2021, and March 4, 2022, a total of 119 consecutive patients with MASLD were included. Liver stiffness was measured using liver biopsy, MRE, VCTE, and FIB-4. Data were collected from outpatient visit charts. Significant fibrosis was defined as ≥ stage 2 fibrosis. All 119 MASLD patients were Caucasian, and their median age was 55 years. MRE, VCTE, and FIB-4 demonstrated significant accuracy in the detection of significant fibrosis with an area under the ROC curve (AUC) of 0.848 ± 0.036 (p < 0.001), 0.632 ± 0.052 (p = 0.012), and 0.664 ± 0.051 (p = 0.001), respectively. However, the diagnostic performance of MRE was superior compared to that of VCTE (AUC difference: 0.216 ± 0.053, p < 0.001) and FIB-4 (AUC difference: 0.184 ± 0.058, p = 0.001). With logistic regression analysis, it was determined that when compared to MRE alone, a combination of MRE and TE (p = 0.880) or MRE and FIB-4 (p = 0.455) were not superior for detecting significant fibrosis. MRE alone is an accurate and non-invasive method for the identification of MASLD patients with significant fibrosis. Magnetic resonance elastography alone accurately detects significant fibrosis in patients with metabolic dysfunction-associated steatotic liver disease. • In routine clinical practice, several non-invasive biochemical-based biomarkers and imaging methods are widely used to assess liver fibrosis in patients with metabolic dysfunction-associated steatotic liver disease. • Magnetic resonance elastography (MRE) is more accuratethanvibration-controlled transient elastography (VCTE) or fibrosis score 4 (FIB-4) for assessing liver fibrosis and identifying significant fibrosis in patients with metabolic dysfunction-associated steatotic liver disease. • The combination of MRE andVCTE or MRE and FIB-4 was not superior to MRE alone.

Magnetic resonance elastography-derived stiffness: potential imaging biomarker for differentiation of benign and malignant pancreatic masses.

This study sought to determine the diagnostic performance of magnetic resonance elastography (MRE) for pancreatic solid masses, compared with diffusion-weighted imaging (DWI) and serum CA19-9, to establish a threshold for differentiating between pancreatic ductal adenocarcinoma (PDAC) and benign tumors in pancreas. Between July 2021 to January 2023, 75 adult patients confirmed with pancreatic solid tumors were enrolled in this prospective and consecutive study. All patients underwent MRE and DWI examinations that were both performed with a spin echo-EPI sequence. Stiffness maps and apparent diffusion coefficient (ADC) maps were generated, with MRE-derived mass stiffness and stiffness ratio (computing as the ratio of mass stiffness to the parenchyma stiffness) and DWI-derived ADC values obtained by placing regions of interest over the focal tumors on stiffness and ADC maps. Further analysis of comparing diagnostic performances was assessed by calculating the area under ROC curves. PDAC had significantly higher tumor stiffness [3.795 (2.879-4.438)kPa vs. 2.359 (2.01-3.507)kPa, P = 0.0003], stiffness ratio [1.939 (1.562-2.511) vs. 1.187 (1.031-1.453), P < 0.0001] and serum CA19-9 level [276 (31.73-1055) vs. 10.45 (7.825-14.15), P < 0.0001] than other pancreatic masses. Mass stiffness, stiffness ratio and serum CA19-9 showed good diagnostic performance for differentiation with AUC of 0.7895, 0.8392 and 0.9136 respectively. The sensitivity/specificity/positive predictive value/negative predictive value for differentiating malignant from benign pancreatic tumors with mass stiffness (cutoff, > 2.8211kPa) and stiffness ratio (cutoff, > 1.5117) were 78.4/66.7/82.9/60% and 77.8/83.3/90.3/65.2% respectively. The combined performance of Mass stiffness, stiffness ratio and serum CA19-9 got an AUC of 0.9758. MRE holds excellent clinical potential in discriminating pancreatic ductal adenocarcinoma from other pancreatic solid masses according to their mechanical properties.

FRI095 - Confounding factors in diagnostic performance of magnetic resonance elastography for staging liver fibrosis in patients with non-alcoholic fatty liver disease: an individual patient data meta-analysis

FRI095 - Confounding factors in diagnostic performance of magnetic resonance elastography for staging liver fibrosis in patients with non-alcoholic fatty liver disease: an individual patient data meta-analysis

Liver stiffness accuracy by magnetic resonance elastography in histologically proven non-alcoholic fatty liver disease patients: a Spanish cohort.

to evaluate the performance of magnetic resonance elastography (MRE) to stage liver fibrosis in patients with histologically confirmed nonalcoholic fatty liver disease (NAFLD) and to assess the impact of potential confounding factors in MRE diagnostic accuracy. The secondary objective was to compare MRE with other non-invasive methods for staging fibrosis such as transient elastography (TE) and non-invasive scores (APRI and FIB-4). sixty-five histologically confirmed NAFLD patients were prospectively enrolled at the Hospital Universitario Virgen del Rocío (Seville, Spain). Liver stiffness was measured by MRE, TE and non-invasive scores (APRI and FIB-4). Fibrosis was assessed by liver biopsy using the steatosis, activity and fibrosis (SAF) score. Patients were classified into three groups according to the consistency between MRE and histopathological findings: underestimation, concordance and overestimation groups. Areas under the ROC curve (AUROC) and diagnostic performance were evaluated. the area under the ROC curve (AUROC) of MRE in advanced fibrosis (≥ F3) was 0.90 (0.82-0.97), while TE AUROC was 0.82 (0.72-0.93) (p = 0.22) and lower for the non-invasive test (FIB-4 0.67 and APRI 0.62). Inflammatory activity, steatosis grade and higher levels of liver biochemistry appeared to overestimate MRE results in the univariate analysis, but only gamma-glutamyl transferase (GGT) was statistically significant in the multivariate analysis (p < 0.01). Age, sex, body mass index (BMI), weight, diabetes mellitus (DM), high blood pressure (HBP), platelets or lipidic profile did not affect MRE accuracy. MRE is an effective and non-invasive method for detecting and staging liver fibrosis in NAFLD patients. MRE is more accurate than TE and allows the study of liver anatomy. Histological inflammation and surrogate biomarkers of inflammation can overestimate liver stiffness, but only GGT was statistically significant in the multivariate analysis. Important features of NAFLD patients such as obesity, DM, or lipidic profile did not affect MRE accuracy.

Magnetic resonance elastography for prediction of long-term progression and outcome in chronic liver disease: A retrospective study.

Although magnetic resonance elastography (MRE) has been well-established for detecting and staging liver fibrosis, its prognostic role in determining outcomes of chronic liver disease (CLD) is mostly unknown. This retrospective study consisted of 1269subjects who underwent MRE between 2007 and 2009 and followed up until death or last known clinical encounter or end of study period. Charts were reviewed for cirrhosis development, decompensation, and transplant or death. The cohort was split into baseline noncirrhosis (group 1), compensated cirrhosis (group 2), and decompensated cirrhosis (group 3). Cox-regression analysis with age, sex, splenomegaly, CLD etiology, Child-Pugh Score (CPS), Fibrosis-4 Index(FIB-4) score, and Model for End-Stage Liver Disease (MELD)-adjusted HR for every 1-kPa increase in liver stiffness measurement (LSM) were used to assess the predictive performance of MRE on outcomes. Group 1(n=821) had baseline median LSM of 2.8kPa, and cirrhosis developed in 72 (8.8%) subjects with an overall rate of about 1% cirrhosis/year. Baseline LSM predicted the future cirrhosis with multivariable adjusted HR of 2.38 (p<0.0001) (concordance, 0.84). Ingroup 2(n=277) with baseline median LSM of 5.7kPa, 83 (30%) subjects developed decompensation. Baseline LSM predicted the future decompensation in cirrhosis with FIB-4 and MELD-adjusted HR of 1.22 (p<0.0001) (concordance, 0.75). Ingroup 3(n=171) with median baseline LSM of 6.8kPa (5.2, 8.4), 113 (66%) subjects had either death or transplant. Baseline LSM predicted the future transplant or death with HR of 1.11 (p=0.013) (concordance 0.53) but not in CPS and MELD-adjusted models (p=0.08). MRE-based LSM is independently predictive of development of future cirrhosis and decompensation, and has predictive value in future transplant/death in patients with CLD.

Added Value of Tomoelastography for Characterization of Pancreatic Neuroendocrine Tumor Aggressiveness Based on Stiffness.

Simple SummaryThe prediction of pancreatic neuroendocrine tumor (PNET) aggressiveness is important for treatment planning. The aim of this study was to evaluate the diagnostic performance of magnetic resonance elastography (MRE) with tomoelastography postprocessing (tomoelastography) in differentiating PNET from healthy pancreatic tissue and to correlate PNET stiffness with aggressiveness using asphericity derived from positron emission tomography (PET) as reference. In this prospective study we showed in a group of 13 patients with PNET that tomoelastography detected PNET by increased stiffness (p < 0.01) with a high diagnostic performance (AUC = 0.96). PNET was positively correlated with PET derived asphericity (r = 0.81). Tomoelastography provides quantitative imaging markers for the detection of PNET and the prediction of greater tumor aggressiveness by increased stiffness.Purpose: To evaluate the diagnostic performance of tomoelastography in differentiating pancreatic neuroendocrine tumors (PNETs) from healthy pancreatic tissue and to assess the prediction of tumor aggressiveness by correlating PNET stiffness with PET derived asphericity. Methods: 13 patients with PNET were prospectively compared to 13 age-/sex-matched heathy volunteers (CTR). Multifrequency MR elastography was combined with tomoelastography-postprocessing to provide high-resolution maps of shear wave speed (SWS in m/s). SWS of pancreatic neuroendocrine tumor (PNET-T) were compared with nontumorous pancreatic tissue in patients with PNET (PNET-NT) and heathy pancreatic tissue (CTR). The diagnostic performance of tomoelastography was evaluated by ROC-AUC analysis. PNET-SWS correlations were calculated with Pearson’s r. Results: SWS was higher in PNET-T (2.02 ± 0.61 m/s) compared to PNET-NT (1.31 ± 0.18 m/s, p < 0.01) and CTR (1.26 ± 0.09 m/s, p < 0.01). An SWS-cutoff of 1.46 m/s distinguished PNET-T from PNET-NT (AUC = 0.89; sensitivity = 0.85; specificity = 0.92) and a cutoff of 1.49 m/s differentiated pancreatic tissue of CTR from PNET-T (AUC = 0.96; sensitivity = 0.92; specificity = 1.00). The SWS of PNET-T was positively correlated with PET derived asphericity (r = 0.81; p = 0.01). Conclusions: Tomoelastography provides quantitative imaging markers for the detection of PNET and the prediction of greater tumor aggressiveness by increased stiffness.

Comparison of magnetic resonance elastography and transient elastography in the diagnosis of hepatic fibrosis: a systematic review and meta-analysis.

Few studies comprehensively compared the performance of magnetic resonance elastography (MRE) and transient elastography (TE) in the diagnosis of liver fibrosis. Therefore, we conducted a meta-analysis to evaluate and compare the diagnostic efficacy of these 2 techniques in patients with hepatic fibrosis in order to gain a better understanding of their overall diagnostic performance and aid in maximizing their clinical utility. Systematic literature searches of the PubMed, EmBase, Cocharane Library, and China National Knowledge Infrastructure databases were carried out to identify studies that applied MRE and TE in the diagnosis of liver fibrosis. The combined sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (ORs) were estimated using a bivariate random effects model. Review Manager 5.2 was used to analyze the selected articles, and forest plot, sensitivity, and bias analyses were performed for the included literature. To determine the diagnostic efficacy of MRE and TE for liver fibrosis, pooled sensitivity and specificity analyses were conducted. Eight studies met the inclusion criteria. In the diagnosis of stage F0-F1 liver fibrosis, MRE showed higher sensitivity than TE (OR =0.62, 95% CI: 0.41-0.95, P=0.03). MRE also showed higher specificity than TE for diagnosing stage F2-F4 liver fibrosis (OR =0.41, 95% CI: 0.27-0.62, P<0.0001). There was no difference in the sensitivity of MRE and Te to F2-F4 hepatic fibrosis and the specificity of MRE and Te to F0-F1 hepatic fibrosis. In terms of sensitivity and specificity, MRE is superior to TE in diagnosing different stages of liver fibrosis to a certain extent. MRE may be a useful, noninvasive method for the assessment of liver fibrosis in patients with chronic liver disease.

MRI quantification techniques in fatty liver: the diagnostic performance of hepatic T1, T2, and stiffness measurements in relation to the proton density fat fraction.

Nonalcoholic fatty liver disease (NAFLD) can progress to liver cirrhosis and is predicted to become the most frequent indication for liver transplantation in the near future. Noninvasive assessment of NAFLD is important for diagnosis and patient management. This study aims to prospectively determine the liver stiffness and T1 and T2 values in patients with NAFLD and to compare the diagnostic performance of magnetic resonance elastography (MRE) and mapping techniques in relation to the proton density fat fraction (PDFF). Eighty-three patients with NAFLD and 26 participants with normal livers were imaged with a 1.5 T scanner. PDFF measurements obtained from the multiecho Dixon technique were used to quantify the liver fat. MRE, native T1 mapping (modified Look-Locker inversion recovery [MOLLI] schemes 5(3)3, 3(3)3(3)5, and 3(2)3(2)5 and the B1-corrected variable flip angle [VFA] method), and T2 mapping values were correlated with PDFF. The diagnostic performance of MRE and the mapping techniques were analyzed and compared. T1 values measured with the MOLLI schemes and the B1-corrected VFA (P < 0.001), and the stiffness values from MRE (P = 0.047) were significantly higher in the NAFLD group. No significant difference was found between the groups in terms of T2 values (P = 0.127). In differentiation of the NAFLD and control groups, the B1-corrected VFA technique had slightly higher accuracy and area under the curve (AUC) than the MOLLI schemes. In the NAFLD group, there was a good correlation between the PDFF, MOLLI 3(3)3(3)5 and 3(2)3(2)5, and VFA T1 measurements (r=0.732; r=0.735; r=0.716, P < 0.001, respectively). Liver T1 mapping techniques have the potential to distinguish steatotic from nonsteatotic livers, and T1 values seem to have a strong correlation with the liver fat content.

Comparison of the diagnostic performance of magnetic resonance elastography and Wisteria foribunda agglutinin-positive Mac-2-binding protein in the determination of advanced liver fibrosis stages in patients with chronic liver disease.

The present study aimed to compare the accuracy of Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+-M2BP) and magnetic resonance elastography (MRE) in determining the liver fibrosis stage in patients with chronic liver disease. A retrospective review of a prospectively maintained database was performed. The eligible patients had hepatic tumors and chronic liver disease, including hepatitis B (HBV) and HCV. All patients underwent blood sampling, MRE and hepatectomy at Changhua Christian Hospital (Changhua, Taiwan). Surgical specimens were used to determine definitive histopathological diagnoses and liver fibrosis stages. Measurement of liver stiffness was performed via MRI. The value of WFA+-M2BP in each patient was also assessed. The area under the receiver operating characteristic (ROC) curve (AUC) was measured to compare the diagnostic accuracy of the two examinations. The results indicated that the serum WFA+-M2BP levels were able to detect severe liver fibrosis (≥F3) in patients with chronic liver disease and performed as well as MRE in patients with HCV. Of the 238 patients enrolled in the present study, 135 had chronic HBV 75 had chronic HCV, 92 had early liver fibrosis (F1-F2) and 139 patients had advanced liver fibrosis (F3-F4). In predicting fibrosis stages ≥F3, MRE had an AUC of 0.89 with a cutoff value of 3.76 and serum WFA+-M2BP had an AUC of 0.65 with a cutoff value of 1.32. MRE had higher AUCs than serum WFA+-M2BP for predicting the severity based on the fibrosis stage in the total cohort and the HBV subgroup. In patients with HCV, no significant differences in diagnostic performance were identified between MRE and serum WFA+-M2BP. In conclusion, determination of WFA+-M2BP as a biomarker for predicting severe liver fibrosis (≥F3) is a reliable and non-invasive method and performs as well as MRE in patients with chronic liver disease, particularly those with HCV.

Magnetic Resonance Elastography of Rodent Brain.

Magnetic resonance elastography (MRE) is a non-invasive imaging technique, using the propagation of mechanical waves as a probe to palpate biological tissues. It consists in three main steps: production of shear waves within the tissue; encoding subsequent tissue displacement in magnetic resonance images; and extraction of mechanical parameters based on dedicated reconstruction methods. These three steps require an acoustic-frequency mechanical actuator, magnetic resonance imaging acquisition, and a post-processing tool for which no turnkey technology is available. The aim of the present review is to outline the state of the art of reported set-ups to investigate rodent brain mechanical properties. The impact of experimental conditions in dimensioning the set-up (wavelength and amplitude of the propagated wave, spatial resolution, and signal-to-noise ratio of the acquisition) on the accuracy and precision of the extracted parameters is discussed, as well as the influence of different imaging sequences, scanners, electromagnetic coils, and reconstruction algorithms. Finally, the performance of MRE in demonstrating viscoelastic differences between structures constituting the physiological rodent brain, and the changes in brain parameters under pathological conditions, are summarized. The recently established link between biomechanical properties of the brain as obtained on MRE and structural factors assessed by histology is also studied. This review intends to give an accessible outline on how to conduct an elastography experiment, and on the potential of the technique in providing valuable information for neuroscientists.

Clinical application of magnetic resonance elastography in chronic liver disease.

Recent evidence highlighted that the accurate assessment of liver fibrosis is important for evaluating the progression of chronic liver disease. During the past decade, many non-invasive methods have been developed to reduce the need for core-needle biopsy in fibrosis staging and to overcome its limitations, such as invasiveness, high cost, low reproducibility, and poor patient consent. The diagnostic performance of magnetic resonance elastography (MRE) is promising for use in clinical practice to evaluate not only liver fibrosis, but also survival and major clinical end-points such as liver decompensation, portal hypertension, development of hepatocellular carcinoma, and surgical outcomes. Together with other clinical markers, MRE can be used to better categorize patients with advanced fibrosis and cirrhosis, and assign them to different classes of risk for significant clinical outcomes. This review discusses clinical applications of MRE in the management strategy of patients with chronic liver disease.

Magnetic Resonance vs Transient Elastography Analysis of Patients With Nonalcoholic Fatty Liver Disease: A Systematic Review and Pooled Analysis of Individual Participants

Magnetic resonance elastography (MRE) and transient elastography (TE) are noninvasive techniques for detection of liver fibrosis. Single-center studies have compared the diagnostic performance of MRE vs TE in patients with nonalcoholic fatty liver disease (NAFLD). We conducted a pooled analysis of individual participant data from published studies to compare the diagnostic performance of MRE vs TE for staging of liver fibrosis in patients with NAFLD, using liver biopsy as reference. We performed a systematic search of publication databases, from 2005 through 2017. We identified 3 studies of adults with NAFLD who were assessed by MRE, TE, and liver biopsy. In a pooled analysis, we calculated the cluster-adjusted area under the curve (AUROC) of MRE and TE for the detection of each stage of fibrosis. AUROC comparisons between MRE and TE were performed using the Delong test. Our pooled analysis included 230 participants with biopsy-proven NAFLD with mean age of 52.2±13.9 years and a body mass index of 31.9±7.5 kg/m2. The proportions of patients with fibrosis of stages 0, 1, 2, 3, and 4 were: 31.7%, 27.8%, 15.7%, 13.9%, and 10.9%, respectively. The AUROC of TE vs MRE for detection of fibrosis stages ≥1 was 0.82 (95% CI, 0.76-0.88) vs 0.87 (95% CI, 0.82-0.91) (P=.04); for stage≥ 2 was 0.87 (95% CI, 0.82-0.91) vs 0.92 (95% CI, 0.88-0.96) (P=.03); for stage ≥3 was 0.84 (95% CI, 0.78-0.90) vs 0.93 (95% CI, 0.89-0.96) (P=.001); for stage ≥ 4 was 0.84 (95% CI, 0.73-0.94) vs 0.94 (95% CI, 0.89-0.99) (P=.005). In a pooled analysis of data from individual participants with biopsy-proven NAFLD, we found MRE to have a statistically significantly higher diagnostic accuracy than TE in detection of each stage of fibrosis. MRE and TE each have roles in detection of fibrosis in patients with NAFLD, depending upon the level of accuracy desired.

Utility of magnetic resonance elastography for predicting ascites in patients with chronic liver disease.

This study aimed to evaluate the utility of magnetic resonance elastography (MRE) as a non-invasive method for predicting ascites in patients with chronic liver disease (CLD). A total of 208 CLD patients underwent MRE to measure liver stiffness (LS) at our institution from March 2013 to June 2015. We evaluated the diagnostic performance of MRE for predicting the presence of ascites using receiver-operating characteristic (ROC) curve analysis and compared the performance with that of serum fibrosis markers. Multivariate logistic regression analysis was performed to identify factors associated with the presence of ascites. The cumulative incidence of ascites was examined in patients without ascites at baseline. The pathological stage of liver fibrosis was evaluated in 81 CLD patients using histopathologic diagnosis. Of the 208 patients, 41 had ascites. The optimal cut-off LS value for the presence of ascites was 6.0kPa (area under the ROC curve=0.87). The area under the ROC curve for the presence of ascites was significantly higher for MRE than that for fibrosis markers. Multivariate analysis revealed that LS >6.0kPa is an independent risk factor for the presence of ascites. The cumulative incidence of ascites was significantly higher among those with LS values >6.0kPa. There was significantly greater diagnostic accuracy for liver fibrosis stage ≥4 with MRE than that with fibrosis markers. Compared with serum fibrosis markers, MRE has higher diagnostic performance in predicting the presence of ascites. MRE-based LS has the potential to predict the presence of ascites in CLD patients.

MR elastography is effective for the non-invasive evaluation of fibrosis and necroinflammatory activity in patients with nonalcoholic fatty liver disease

ObjectivesTo evaluate the performance of magnetic resonance elastography (MRE) in diagnosing and staging hepatic fibrosis in patients with histologically confirmed nonalcoholic fatty liver disease (NAFLD) and in distinguishing simple steatosis from nonalcoholic steatohepatitis (NASH). MethodsNinety subjects (49 NAFLD patients and 41 healthy volunteers) were prospectively enrolled. Liver stiffness measured by MRE was correlated with the grade of fibrosis and/or inflammation determined by liver biopsy. Correlations, ROC (receiver operator characteristic) curves and diagnostic performance were evaluated. The study was approved by the local ethics committee. ResultsThe area under the ROC curve (AUROC) of MRE in discriminating healthy from NAFLD individuals was 0.964 (P<0.0001), and that for distinguishing advanced (F3-F4) from absent/mild fibrosis (F0-F2) was 0.928 (P<0.0001). The use of a threshold >4.39 kPa resulted in a sensitivity of 90.9% and a specificity of 97.3% for diagnosing advanced fibrosis. For discriminating NASH from simple steatosis, the AUROC was 0.783 (P<0.0001), and the threshold, 3.22 kPa. ConclusionsMRE is an effective, non-invasive method for detecting/staging hepatic fibrosis in NAFLD. This method has good performance in discriminating normal from NAFLD subjects and between the extreme grades of fibrosis. NAFLD patients with inflammation and without fibrosis have higher liver stiffness than those with simple steatosis.

Prospective Comparison of the Diagnostic Performance of Magnetic Resonance Elastography with Acoustic Radiation Force Impulse Elastography for Pre-operative Staging of Hepatic Fibrosis in Patients with Hepatocellular Carcinoma

The purpose of this study was to compare the diagnostic accuracy of magnetic resonance (MR) elastography with that of acoustic radiation force impulse (ARFI) elastography for pre-operative staging of hepatic fibrosis in patients with hepatocellular carcinoma. We prospectively enrolled 77 patients who were scheduled to undergo hepatectomy for hepatocellular carcinoma. Pre-operative MRE and ARFI elastography examinations were performed on the same day, and liver stiffness/velocity values were determined. Fibrosis stage and necro-inflammatory activity of resected specimens were determined histopathologically using the METAVIR scoring system. Correlations between MRE and ARFI elastography findings and histologic findings were determined by receiver operating characteristic (ROC) analysis. Correlation of MRE was excellent and correlation of ARFI elastography was good with fibrosis stage. MRE had better diagnostic performance than ARFI elastography in estimating substantial fibrosis (F2), severe fibrosis (F3) and cirrhosis (F4). The optimal cutoff value and the area under the ROC curve (AUROC) were determined using ROC curve analysis. The highest Youden index was used as a criterion for selecting the optimal cutoff value. ROC analysis revealed that MRE discriminated advanced stages of fibrosis (F ≥ 2) well in patients with hepatocellular carcinoma at a cutoff value of 3.0 kPa with an AUROC value of 0.93, and ARFI elastography did so at a cutoff value of 1.77 m/s with an AUROC value of 0.81 for predicting advanced stages of fibrosis (F ≥ 2). In conclusion, MRE is a more accurate imaging modality than ARFI elastography in estimating advanced stages of fibrosis and cirrhosis.

Magnetic resonance elastography in the assessment of hepatic fibrosis: a study comparing transient elastography and histological data in the same patients.

To evaluate the quantitative measurement of liver stiffness (LS), compare the diagnostic performance of magnetic resonance elastography (MRE) and ultrasound-based transient elastography (TE), and evaluate two different MRE-based LS measurement methods. Between October 2013 and January 2015, 116 consecutive patients with chronic liver disease underwent MRE to measure LS (kilopascals; kPa). Of the 116 patients, 51 patients underwent both TE and liver biopsy, and the interval between the liver biopsy and both the MRE and TE was less than 90days. MRE-derived LS values were measured on the anterior segment of the right lobe (single small round regions of interest per slice; srROIs) and whole right lobe of the liver (free hand region of interest; fhROI), and these values were correlated with pathological fibrosis grades and diagnostic performance. Pathological fibrosis stage was significantly correlated with srROIs (r=0.87, p<0.001), fhROI (r=0.80, p<0.001), and TE (r=0.73, p<0.001). For detection of significant fibrosis (≥F2), advanced fibrosis (≥F3), and cirrhosis, the area under the curve (AUC) associated with the srROIs was largest, and there was a significant difference between srROIs and TE (0.93 vs. 0.82, p=0.006), srROIs and fhROI (0.93 vs. 0.89, p=0.04) for detection of ≥F2. For advanced fibrosis and cirrhosis detection, AUCs were not significant (0.92-0.96). MRE and TE detected liver fibrosis with comparable accuracy. In particular, the srROIs method was effective for detecting of significant fibrosis.

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Magnetic resonance elastography is accurate in detecting advanced fibrosis in autoimmune hepatitis.

AIMTo assess the value of magnetic resonance elastography (MRE) in detecting advanced fibrosis/cirrhosis in autoimmune hepatitis (AIH).METHODSIn this retrospective study, 36 patients (19 treated and 17 untreated) with histologically confirmed AIH and liver biopsy performed within 3 mo of MRE were identified at a tertiary care referral center. Liver stiffness (LS) with MRE was calculated by a radiologist, and inflammation grade and fibrosis stage in liver biopsy was assessed by a pathologist in a blinded fashion. Two radiologists evaluated morphological features of cirrhosis on conventional magnetic resonance imaging (MRI). Accuracy of MRE was compared to laboratory markers and MRI for detection of advanced fibrosis/cirrhosis.RESULTSLiver fibrosis stages of 0, 1, 2, 3 and 4 were present in 4, 6, 7, 6 and 13 patients respectively. There were no significant differences in distribution of fibrosis stage and inflammation grade between treated and untreated patient groups. LS with MRE demonstrated stronger correlation with liver fibrosis stage in comparison to laboratory markers for chronic liver disease (r = 0.88 vs -0.48-0.70). A trend of decreased mean LS in treated patients compared to untreated patients was observed (3.7 kPa vs 3.84 kPa) but was not statistically significant. MRE had an accuracy/sensitivity/specificity/positive predictive value/negative predictive value of 0.97/90%/100%/100%/90% and 0.98/92.3%/96%/92.3%/96% for detection of advanced fibrosis and cirrhosis, respectively. The performance of MRE was significantly better than laboratory tests for detection of advanced fibrosis (0.97 vs 0.53-0.80, P < 0.01), and cirrhosis (0.98 vs 0.58-0.80, P < 0.01) and better than conventional MRI for diagnosis of cirrhosis (0.98 vs 0.78, P = 0.002).CONCLUSIONMRE is a promising modality for detection of advanced fibrosis and cirrhosis in patients with AIH with superior diagnostic accuracy compared to laboratory assessment and MRI.

Magnetic Resonance Elastography vs Transient Elastography in Detection of Fibrosis and Noninvasive Measurement of Steatosis in Patients With Biopsy-Proven Nonalcoholic Fatty Liver Disease

Magnetic resonance imaging (MRI) techniques and ultrasound-based transient elastography (TE) can be used in noninvasive diagnosis of fibrosis and steatosis in patients with nonalcoholic fatty liver disease (NAFLD). We performed a prospective study to compare the performance of magnetic resonance elastography (MRE) vs TE for diagnosis of fibrosis, and MRI-based proton density fat fraction (MRI-PDFF) analysis vs TE-based controlled attenuation parameter (CAP) for diagnosis of steatosis in patients undergoing biopsy to assess NAFLD. We performed a cross-sectional study of 104 consecutive adults (56.7% female) who underwent MRE, TE, and liver biopsy analysis (using the histologic scoring system for NAFLD from the Nonalcoholic Steatohepatitis Clinical Research Network Scoring System) from October 2011 through May 2016 at a tertiary medical center. All patients received a standard clinical evaluation, including collection of history, anthropometric examination, and biochemical tests. The primary outcomes were fibrosis and steatosis. Secondary outcomes included dichotomized stages of fibrosis and nonalcoholic steatohepatitis vs no nonalcoholic steatohepatitis. Receiver operating characteristic curve analyses were used to compare performances of MRE vs TE in diagnosis of fibrosis (stages 1-4 vs 0) and MRI-PDFF vs CAP for diagnosis of steatosis (grades 1-3 vs 0) with respect to findings from biopsy analysis. MRE detected any fibrosis (stage 1 or more) with an area under the receiver operating characteristic curve (AUROC) of 0.82 (95% confidence interval [CI], 0.74-0.91), which was significantly higher than that of TE (AUROC, 0.67; 95% CI, 0.56-0.78). MRI-PDFF detected any steatosis with an AUROC of 0.99 (95% CI, 0.98-1.00), which was significantly higher than that of CAP (AUROC, 0.85; 95% CI, 0.75-0.96). MRE detected fibrosis of stages 2, 3, or 4 with AUROC values of 0.89 (95% CI, 0.83-0.96), 0.87 (95% CI, 0.78-0.96), and 0.87 (95% CI, 0.71-1.00); TE detected fibrosis of stages 2, 3, or 4 with AUROC values of 0.86 (95% CI, 0.77-0.95), 0.80 (95% CI, 0.67-0.93), and 0.69 (95% CI, 0.45-0.94). MRI-PDFF identified steatosis of grades 2 or 3 with AUROC values of 0.90 (95% CI, 0.82-0.97) and 0.92 (95% CI, 0.84-0.99); CAP identified steatosis of grades 2 or 3 with AUROC values of 0.70 (95% CI, 0.58-0.82) and 0.73 (95% CI, 0.58-0.89). In a prospective, cross-sectional study of more than 100 patients, we found MRE to be more accurate than TE in identification of liver fibrosis (stage 1 or more), using biopsy analysis as the standard. MRI-PDFF is more accurate than CAP in detecting all grades of steatosis in patients with NAFLD.