Magnetic Resonance Elastography In Patients Research Articles

The Relationship Between Conventionally Obtained Serum-Based Liver Function Indices and Intravoxel Incoherent Motion Diffusion-Weighted Imaging and Magnetic Resonance Elastography in Patients With Hepatocellular Carcinoma.

To investigate the relationship between conventionally obtained serum-based biochemical indices and intravoxel incoherent motion imaging (IVIM) parameters compared with magnetic resonance elastography (MRE). Patients with hepatocellular carcinoma who underwent ≥2 liver magnetic resonance imaging (MRI) scan, including IVIM and MRE, between 2017 and 2020 and biochemical testing within 1 week before or after MRI were included in this study. Biochemical tests were performed to determine the albumin-bilirubin (ALBI) score and modified ALBI (mALBI) grade, aspartate aminotransferase to platelet ratio index (APRI), and fibrosis-4 index (FIB-4). The diffusion coefficient ( D ), pseudo-diffusion coefficient ( D *), fractional volume occupied by flowing spins ( f ), and apparent diffusion coefficient were calculated for IVIM. The correlations between (1) the imaging parameters and biochemical indices and (2) the changes in mALBI grades and imaging parameters were evaluated. This study included 98 scans of 40 patients (31 men; mean age, 67.7 years). The correlation analysis between the biochemical and IVIM parameters showed that ALBI score and D* had the best correlation ( r = -0.3731, P < 0.001), and the correlation was higher than that with MRE ( r = 0.3289, P < 0.001). However, among FIB-4, APRI, and MRI parameters, MRE outperformed IVIM parameters (MRE and FIB-4, r = 0.3775, P < 0.001; MRE and APRI, r = 0.4687, P < 0.001). There were significant differences in the changes in MRE among the 3 groups (improved, deteriorated, and unchanged mALBI groups) in the analysis of covariance ( P = 0.0434). There were no significant changes in IVIM. Intravoxel incoherent motion imaging has the potential to develop into a more readily obtainable method of liver function assessment.

Technical Success and Reliability of Magnetic Resonance Elastography in Patients with Hepatic Iron Overload

This study aimed to evaluate the technical success rate and stiffness measurement reliability of two specific hepatic magnetic resonance elastography (MRE) sequences dedicated to solving susceptibility artifacts in patients with various degrees of hepatic iron overload. Thirty-seven patients with iron-overloaded liver confirmed by R2* value measurement who underwent two-dimensional (2D) spin-echo (SE) MRE and 2D SE-echo-planar-imaging (EPI) MRE were reviewed retrospectively. According to four categories based on R2* value (mild, moderate, severe elevation, and extremely severe iron overload), we compared the success rate, quality score, and liver stiffness of the two sequences. In addition, Spearman's correlation was performed to evaluate the relationship between the R2* value and liver stiffness. The overall success rates of SE MRE and SE-EPI MRE in patients with hepatic iron overload were 91.89% and 78.38%, respectively, and 100% and 78.57%, respectively, for severe elevation iron overload. In all patients, the MRE quality scores were 54 and 48 for SE MRE and SE-EPI MRE, respectively (P=0.107). There were no significant differences in liver stiffness measurements between the two MRE methods in patients with mild, moderate, and severe elevation iron-overloaded livers (P>0.6 for all), respectively. For both MRE methods, R2* value had no significant effect on the liver stiffness measurements (correlation coefficient <0.1, P >0.6 for both). In the mild and moderate elevation iron-overloaded liver, both SE MRE and fast SE-EPI MRE can provide successful and reliable liver stiffness measurement. In severe elevation iron-overloaded livers, SE MRE may be a better choice than SE-EPI MRE.

Noninvasive Assessment of Liver Fibrosis by Magnetic Resonance Elastography in Patients with Rheumatic Disease on Long-Term Methotrexate Treatment

Background: Long-term methotrexate (MTX) use is associated with hepatic fibrosis in patients with rheumatic diseases. Liver biopsy (invasive conventional diagnostic procedure for hepatic fibrosis) is associated with sampling errors and procedural risks. Magnetic resonance elastography (MRE) is a novel, reliable, and noninvasive imaging technique with excellent diagnostic accuracy for staging hepatic fibrosis and cirrhosis. Till date, studies are scarce on its use in staging MTX-induced liver fibrosis and cirrhosis. The aim of this study is to assess the usefulness of MRE in detecting and quantifying liver fibrosis and to compare these with biochemical parameters in patients with rheumatic diseases on long-term MTX therapy. Methods: Patients with different rheumatic diseases, aged ≥18 years and on MTX treatment for >5 years were included in the study. Their medical records were reviewed, and data regarding demographics, diagnosis, disease duration, MTX dosage and duration were collected. On the day of MRE examination, series of biochemical parameters were conducted in patients. Predefined cutoff MRE values were used for staging liver fibrosis. Results: A total of 48 subjects diagnosed with different rheumatic diseases on long-term MTX were recruited in the study, and majority of them were female (n = 41). The mean age and body mass index of the patients were 53.56 ± 8.36 years and 28.08 ± 4.43, respectively. Around 37.5% (n = 18) of the patients had abnormal aspartate transaminase (AST)-to-platelet count ratio index (APRI) score. The mean MRE value of the study group was 2.83 ± 0.90 kPa. Around 45.83% (n = 22) of the patients had normal liver stiffness values (<2.5) whereas stages F0 (2.5–2.9 kPa), F1 (2.9–3.5 kPa), F2 (3.5–4.0 kPa), F3 (4.0–5.0 kPa), and F4 (>5.0 kPa) were observed in 12.5% (n = 6), 18.75% (n = 9), 10.42% (n = 5), 10.42% (n = 5), and 2.08% (n = 1) of the patients, respectively. MRE values did not correlate with disease duration and cumulative dose of MTX. However, a positive correlation was observed between MRE and liver biochemical parameters (AST: Alanine transaminase [ALT] ratio, ALT, platelet count, APRI, albumin, and mean liver size; P > 0.05). Conclusion: Considering the risk for complications with liver biopsy, MRE provides a reliable, highly accurate, noninvasive assessment of hepatic fibrosis in patients with rheumatic diseases receiving long-term MTX therapy.

Magnetic Resonance Elastography in Intracranial Neoplasms: A Scoping Review.

Magnetic resonance elastography (MRE) allows noninvasive assessment of intracranial tumor mechanics and may thus be predictive of intraoperative conditions. Variations in the use of technical terms complicate reading of current literature, and there is need of a review using consolidated nomenclature. We present an overview of current literature on MRE relating to human intracranial neoplasms using standardized nomenclature suggested by the MRE guidelines committee. We then discuss the implications of the findings, and suggest approaches for future research. We performed a systematic literature search in PubMed, Embase, and Web of Science; the articles were screened for relevance and then subjected to full text review. Technical terms were consolidated. We identified 12 studies on MRE in patients with intracranial tumors, including meningiomas, glial tumors including glioblastomas, vestibular schwannomas, hemangiopericytoma, central nervous system lymphoma, pituitary macroadenomas, and brain metastases. The studies had varying objectives that included prediction of intraoperative consistency, histological separation, prediction of adhesiveness, and exploration of the mechanobiology of tumor invasiveness and malignancy. The technical terms were translated using standardized nomenclature. The literature was highly heterogeneous in terms of image acquisition techniques, post-processing, and study design and was generally limited by small and variable cohorts. MRE shows potential in predicting tumor consistency, adhesion, and mechanical homogeneity. Furthermore, MRE provides insight into malignant tumor behavior and its relation to tissue mechanics. MRE is still at a preclinical stage, but technical advances, improved understanding of soft tissue rheological impact, and larger samples are likely to enable future clinical introduction.

Tissue stiffness in BPH patients from magnetic resonance elastography

BackgroundBPH is commonly found in older men which can lead to lower urinary tract symptoms. Magnetic resonance elastography (MRE) is an innovative, noninvasive imaging technique used to evaluate tissue stiffness. There has not been any study, however, that assessed the tissue stiffness in patients with BPH. A prospective descriptive study was performed to demonstrated MRI and MRE techniques of the prostate gland in ten patients with BPH to assess tissue stiffness, features of BPH on MRI and components of BPH in the area of increased stiffness.ResultsMRI and MRE examinations in all patients were successful without any complications. The mean tissue stiffness of the whole prostate gland was 4.40 ± 0.71 kPa with good reproducibility (ICC 0.82). Stromal components and mixed glandular-stromal components tended to be associated with the areas of increased stiffness on stiffness images, 50.6% for stromal components and 37.9% for mixed glandular-stromal components. Some MRI findings were seen on the patients with high mean stiffness values such as prostatic calcification, type-5 BPH pattern and large prostate volumes.ConclusionsProstate MRE is a useful noninvasive reproducible diagnostic tool for evaluating prostate tissue stiffness by both qualitative and quantitative assessments. The mean prostate tissue stiffness from MRE in patients with BPH in this study was 4.40 ± 0.71 kPa. Some MRI features might be associated with increased tissue stiffness.Trial registration: PID 229. Registered 4 October 2019. http://md.redcap.kku.ac.th

Clinical utility of 3D magnetic resonance elastography in patients with biliary obstruction.

Three-dimensional magnetic resonance elastography (3D-MRE) allows for multiparametric modeling of both elastic and viscous tissue characteristics. Our aim was to compare 3D-MRE with conventional liver shear stiffness assessment in gauging obstructive jaundice (OJ), predicting the adequacy of biliary decompression after drainage, and discriminating OJ from liver fibrosis. Patients with no histories of liver disease (n = 201) were studied in retrospect, grouped by bilirubin levels as no jaundice (NJ ≤ 2 mg/dL; n = 75), mild OJ (>2 mg/dL and ≤ 4 mg/dL; n = 56), and severe OJ (> 4 mg/dL; n = 70). For comparison, another 75 patients with chronic hepatitis B and C infections and histologically proven liver fibrosis were similarly analyzed. Each patient underwent spin-echo echo-planar-imaging MRE at 60Hz with 3D wave postprocessing. Logistic regression and ordinary regression models were used to compare the 3D-MRE model with liver shear stiffness. Liver shear stiffness, loss modulus, and damping ratio were incorporated into a 3D-MRE model, which significantly outperformed shear stiffness in predicting OJ severity (accuracy: 0.801 vs 0.672; p < 0.001). Both the 3D-MRE model and liver shear stiffness performed equally well in predicting the outcome of biliary drainage procedure (C-statistics: 0.852 vs 0.847; p = 0.48). The 3D-MRE model also demonstrated significantly better C-statistics than that of liver shear stiffness in discriminating mild OJ from F1-F2 liver fibrosis (0.765 vs 0.641; p = 0.005) and severe OJ from F3-F4 liver fibrosis (0.750 vs 0.635; p = 0.031). 3D-MRE is an innovative imaging method for gauging OJ severity, predicting the outcome of biliary drainage procedure, and discriminating OJ from liver fibrosis. • 3D-MR elastography achieved promising results for predicting the severity of obstructive jaundice. • Advanced parameters of 3D-MR elastography demonstrated significantly better performance than that of shear stiffness of 2D-MR elastography in discriminating obstructive jaundice from liver fibrosis caused by chronic hepatitis B/C. • Both 3D-MR elastography and 2D-MR elastography were equivalent in predicting the outcome of biliary drainage procedure.

Liver stiffness by magnetic resonance elastography is associated with increased risk of cardiovascular disease in patients with non-alcoholic fatty liver disease.

Magnetic resonance elastography (MRE) is a reliable non-invasive alternative to liver biopsy for assessing liver fibrosis. There are limited data regarding an association between liver fibrosis by MRE and risk of cardiovascular disease (CVD). To investigate the association of high-risk CVD phenotype determined by coronary artery calcification (CAC) with liver fibrosis by MRE in patients with non-alcoholic fatty liver disease (NAFLD). This was a cross-sectional analysis of well-characterised, prospective cohorts including 105 patients with NAFLD (MR imaging-derived proton density fat fraction ≥ 5%) with contemporaneous cardiac computed tomography (CT) and MRE. Patients were assessed using MRE for liver stiffness, and cardiac CT for the presence of CAC (defined as coronary artery calcium score > 0). Odds of presence of CAC were analysed using logistic regression analysis. The average age and body mass index were 54.9years and 32.9kg/m2 respectively. In this cohort, 49.5% of patients had CAC and 35.2% had significant liver fibrosis (defined as MRE ≥2.97kPa). Compared to patients without CAC, those with CAC were older (50.0 [39.0-59.0] vs 63.0 [55.5-67.5], P<0.001) and had higher Framingham risk score (FRS, 1.0 [0.5-3.5] vs 6.0 [2.0-12.0], P<0.001). In multivariable-adjusted analysis, liver stiffness as a continuous trait on MRE was independently associated with the presence of CAC in a sex and age-adjusted model (adjusted odd ratios [aOR]=2.23, 95% confidence interval [CI]=1.31-4.34, P=0.007) as well as in a FRS-adjusted model (aOR=2.16, 95% CI=1.29-4.09, P=0.008). When analysed as a dichotomous trait, significant fibrosis (MRE-stiffness ≥2.97kPa) remained independently associated with the presence of CAC in both FRS-adjusted model and sex and age-adjusted model (aOR=3.21-3.53, P=0.013-0.017). In addition, CAC was more prevalent in patients with significant fibrosis than those without as determined by MRE (67.6% vs 39.7%, P=0.012). Liver stiffness determined by MRE is an independent predictor for the presence of CAC in patients with NAFLD. Patients with NAFLD and significant fibrosis by MRE should be considered for further cardiovascular risk assessment, regardless of their FRS.

Evaluating the Short-Term Clinical Efficacy of Magnetic Resonance Elastography in Patients with Budd-Chiari Syndrome

To investigate the clinical relevance of liver stiffness (LS) in evaluating liver function properties in patients with Budd-Chiari syndrome (BCS) with different severities and LS variation before and after endovascular intervention. Between December 2016 and March 2019, patients with a diagnosis of BCS were considered for enrollment consecutively in our study. Liver function of these patients was classified according to Child-Pugh grading standard before treatment. Liver function parameters were recorded, including albumin, alanine aminotransferase, aspartate aminotransferase, prothrombin time, and total bilirubin. LS was measured with MR elastography (MRE) before and after treatment. Pearson correlation analysis was performed to measure the correlation between LS and liver function-related parameters. Univariate analysis of variance test was used to compare LS and clinical quantitative variables of patients in three different Child-Pugh categories. Paired t test with a significant threshold of p = 0.05 was used to compare LS and pressure gradient of these patients before and after treatment. Correlation analysis between changes in LS and that in pressure gradient was performed by linear regression. A total of 43 patients (23 males and 20 females) were finally enrolled in this study. The mean LS in the three groups was 5.67 ± 1.15 kPa (Child-Pugh A), 6.31 ± 1.13 kPa (Child-Pugh B), and 8.27 ± 2.22 kPa (Child-Pugh C), respectively. LS showed significant difference for patients with different Child-Pugh grades (F = 9.536, p < 0.001). Prothrombin time and total bilirubin were positively correlated with LS (p < 0.05). After treatment, mean LS in three groups was 4.83 ± 1.06 kPa, 5.12 ± 0.93, and 7.37 ± 1.96, respectively. LS decreased significantly in all three Child-Pugh grades (p < 0.001 from Child-Pugh A, p < 0.001 from Child-Pugh B, p = 0.009 from Child-Pugh C). The mean pressure gradient before intervention was 17.6 ± 4.9 mm Hg, and 8.7 ± 7.2 mm Hg after the treatment (p < 0.001). The changes in LS were correlated to that in pressure gradients (r = 0.439; r2 = 0.193; p = 0.015). MR elastography for LS measurement has been demonstrated to act as an effective tool to evaluate liver function, and to monitor the BCS patients in follow-up treatments.

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.

SAT-264-Prediction of hepatocellular carcinoma development using liver stiffness after sustained virological responses by magnetic resonance elastography in patients with chronic hepatitis C

SAT-264-Prediction of hepatocellular carcinoma development using liver stiffness after sustained virological responses by magnetic resonance elastography in patients with chronic hepatitis C

Prediction of major complications after hepatectomy using liver stiffness values determined by magnetic resonance elastography.

Liver fibrosis is a risk factor for hepatectomy but cannot be determined accurately before hepatectomy because diagnostic procedures are too invasive. Magnetic resonance elastography (MRE) can determine liver stiffness (LS), a surrogate marker for assessing liver fibrosis, non-invasively. The aim of this study was to investigate whether the LS value determined by MRE is predictive of major complications after hepatectomy. This prospective study enrolled consecutive patients who underwent hepatic resection between April 2013 and August 2016. LS values were measured by imaging shear waves by MRE in the liver before hepatectomy. The primary endpoint was major complications, defined as Clavien-Dindo grade IIIa or above. Logistic regression analysis identified independent predictive factors, from which a logistic model to estimate the probability of major complications was constructed. A total of 96 patients were included in the study. Major complications were observed in 15 patients (16 per cent). Multivariable logistic analysis confirmed that higher LS value (P = 0·021) and serum albumin level (P = 0·009) were independent predictive factors for major complications after hepatectomy. Receiver operating characteristic (ROC) analysis showed that the best LS cut-off value was 4·3 kPa for detecting major complications, comparable to liver fibrosis grade F4, with a sensitivity of 80 per cent and specificity of 82 per cent. A logistic model using the LS value and serum albumin level to estimate the probability of major complications was constructed; the area under the ROC curve for predicting major complications was 0·84. The LS value determined by MRE in patients undergoing hepatectomy was an independent predictive factor for major complications.

Prognostic Role of Liver Stiffness Measurements Using Magnetic Resonance Elastography in Patients with Compensated Chronic Liver Disease.

To retrospectively evaluate the prognostic role of liver stiffness (LS) measurement using magnetic resonance elastography (MRE) in patients with compensated chronic liver disease (cCLD). We enrolled 217 patients with cCLD who underwent MRE. After mean follow-up of 45.0 ± 17.6 months, cumulative incidence (CI) of hepatocellular carcinoma (HCC) occurrence, development of decompensation and overall survival (OS) were estimated using the Kaplan-Meier method. Prognostic factors were evaluated using the Cox proportional hazard regression model. During the follow-up period, HCC occurred in 33 patients, and 1-, 3- and 5-year CIs of HCC occurrence were 3.8%, 14.8% and 18.9%, respectively. The LS value was a significant predictive factor for HCC occurrence [p < 0.001, hazard ratio (HR) = 1.59 per unit (1.25-2.03)]. Eighteen patients experienced hepatic decompensation, and 1-, 3- and 5-year CIs of decompensation were 2.8%, 7.3% and 11.3%, respectively. The LS value was also significantly associated with decompensation development [p < 0.001, HR = 2.02 per unit (1.37-2.98)]. Fourteen patients died, and 1-, 3- and 5-year OSs were 99.1%, 98.0% and 89.8%, respectively. The LS value was demonstrated to be a significant affecting factor for OS [p = 0.008, HR = 1.39 per unit (1.10-1.78)]. LS obtained from MRE was a significant predictive factor for the development of decompensation, HCC occurrence and OS in cCLD patients. • Liver stiffness (LS) values obtained from MRE can provide prognostic information. • The LS value was a significant predictive factor for occurrence of hepatocellular carcinoma. • The LS value was significantly associated with development of hepatic decompensation. • Survival of compensated chronic liver disease patients was affected by the LS value.

Non-invasive assessment of liver fibrosis by magnetic resonance elastography in patients with congenital heart disease undergoing the Fontan procedure and intracardiac repair

BackgroundThe incidence of late liver complications such as fibrosis or cirrhosis has increased among patients who have undergone the Fontan procedure. Magnetic resonance elastography (MRE) recently emerged as a technique to clinically evaluate liver fibrosis. However, few reports have described its use in evaluating liver fibrosis in children with congenital heart disease (CHD). Methods and resultsFifty-seven children were examined and divided into four groups: 27 with CHD who underwent intracardiac repair (ICR); 16 with CHD who underwent the Fontan procedure (Fontan); 14 in a control group (control); and two with cirrhosis (cirrhosis). Liver stiffness (LS) was measured using MRE. Other assessments included central venous pressure (CVP) as determined by cardiac catheterization. Circulating biomarker levels were also determined. There were no significant differences in biomarker levels among the groups. However, the LS degree was significantly higher in the Fontan group than in the control group. On stepwise multivariate analysis, only the CVP level was a statistically significant independent predictor of LS. There was also a strong correlation between LS and CVP and between LS and time interval since Fontan surgery. ConclusionsThis study clearly demonstrated that LS was significantly increased after the Fontan procedure and that CVP was a predictor of LS. MRE is a highly sensitive tool that can evaluate liver fibrosis in children who undergo the Fontan procedure and enable earlier detection of LS than biomarkers.

Evaluation of liver stiffness with magnetic resonance elastography in patients with constrictive pericarditis: Preliminary findings.

To evaluate with magnetic resonance elastography (MRE) whether patients with constrictive pericarditis (CP) have increased hepatic stiffness. CP results in reduced pericardial compliance, ventricular interdependence, and right heart failure. Patients with untreated CP may develop liver fibrosis and ultimately cirrhosis due to chronic venous congestion. Chronic venous congestion ± fibrosis may lead to increased liver stiffness. Prospectively, patients with suspected CP underwent 2D transthoracic echocardiography, cardiac MRI, and liver MRE. An automated method was used to draw regions of interest (ROIs) on the stiffness maps to calculate the mean liver stiffness in kilopascals (kPa). A t-test with α = 0.05 was performed between stiffness values of patients with positive and negative CP findings based on previously published echocardiography criteria. Nineteen patients met inclusion criteria with a mean ± standard deviation (SD) age of 51 ± 16 years. Nine patients (47%) had CP. Mean liver stiffness trended higher in patients with CP compared to those without CP (4.04 kPa vs. 2.46; P = 0.045). Liver stiffness correlated with MRI septal bounce (P = 0.04), inferior vena cava size (P = 0.003), echo abnormal septal motion (P = 0.04), and echo mitral inflow variation >25% (P = 0.02). Only MRI septal bounce predicted CP by echocardiography (P < 0.001). CP was associated with increased liver stiffness. The increased stiffness is most likely secondary to chronic hepatic venous congestion and/or fibrosis. MRE may be useful for noninvasive liver stiffness assessment in CP. J. Magn. Reson. Imaging 2016;44:81-88.

Non-Invasive Evaluation of Hepatic Fibrosis: The Diagnostic Performance of Magnetic Resonance Elastography in Patients with Viral Hepatitis B or C

PurposeTo compare the accuracy of magnetic resonance elastography (MRE) with that of aspartate aminotransferase-to-platelet ratio index (APRI) for estimating the stage of hepatic fibrosis in patients with chronic hepatitis B virus (HBV) or chronic hepatitis C virus (HCV) infection.Materials and MethodsWe retrospectively enrolled 160 patients with chronic hepatitis and 25 healthy living liver donors. Fibrosis stage (METAVIR, F0 to F4) was determined histopathologically for all patients. APRI was recorded at the time of histopathologic examination and liver stiffness values were measured on MRE quantitative stiffness maps. The cutoff values, sensitivity, and specificity of MRE and APRI for each fibrosis stage were determined using receiver operating characteristic (ROC) analysis.ResultsMRE had a significantly greater area under the ROC curve than APRI score for discriminating among METAVIR stages F2-F4. Using a cutoff value of 2.80 kPa, MRE had a sensitivity of 94.4% and a specificity of 97.8% for detecting significant fibrosis (≥F2). There were no significant differences in fibrosis stage between patients with HBV and those with HCV infection. For ≥F2, the cutoffs were 2.47 kPa (100% sensitivity), 2.80 kP (maximum sum of sensitivity and specificity), and 3.70 kPa (100% specificity).ConclusionsMRE is a more accurate modality than APRI for detecting significant fibrosis in patients with chronic HBV or HCV infection. Antiviral treatment should be considered in patients with liver stiffness values ≥ 2.8 kPa.

Diagnostic value of magnetic resonance elastography for detecting and staging of hepatic fibrosis: A meta-analysis

A meta-analysis was performed to evaluate the diagnostic value of magnetic resonance elastography (MRE) in detecting and staging hepatic fibrosis. A systematic search of PubMed, EMBASE, Web of Science, and Cochrane Library Database up to October 2013 was undertaken to find studies on the evaluation of MRE in patients suspected of hepatic fibrosis. Data from the articles were analysed using Meta-disc 1.4 and Stata 12.0 software. The sensitivity, specificity, and area under the summary receiver operating characteristic (ROC) curve (AUROC) were pooled for all stages of hepatic fibrosis (F ≥ 1, F ≥ 2, F ≥ 3, and F = 4). Publication bias was assessed through the Deeks' funnel plot asymmetry tests. Thirteen studies comprising 989 patients met the inclusion criteria. The pooled sensitivity and specificity for F ≥ 1, F ≥ 2, F ≥ 3, and F = 4 were 0.87 (95% CI = 0.84-0.89) and 0.92 (95% CI = 0.87-0.96), 0.87 (95% CI = 0.84-0.90) and 0.92 (95% CI = 0.89-0.95), 0.88 (95% CI = 0.85-0.91) and 0.91 (95% CI = 0.88-0.93), 0.91 (95% CI = 0.87-0.94) and 0.92 (95% CI = 0.89-0.94), respectively. The pooled AUROC for F ≥ 1, F ≥ 2, F ≥ 3, and F = 4 were 0.9502, 0.9663, 0.9644, and 0.9768, respectively. The non-significant slope of Deeks' funnel plot asymmetry tests indicated that no significant bias was found. MRE has a high diagnostic accuracy for the quantitative detection and staging of hepatic fibrosis.

The feasibility of endorectal MR elastography for prostate cancer localization

The objectives of this study were to evaluate the feasibility of using a rigid radio-frequency receiver endorectal coil for intracavitary prostate magnetic resonance elastography (MRE) and to demonstrate the capability of this technique for generating stiffness maps over a typical prostate volume. An endorectal coil is currently used to help improve the signal-to-noise ratio of images acquired with multiparametric magnetic resonance imaging. We propose that this same coil could also serve to generate shear waves in the prostate gland during imaging, opening up the possibility of incorporating prostate stiffness characterization into multiparametric magnetic resonance imaging. Prostate cancer has been shown to change the elasticity of tissue, suggesting that stiffness imaging (elastography) may provide supplementary diagnostic information. A rigid endorectal coil was mechanically coupled to a piezoceramic actuator and used to investigate full volume (27 slices, 2-mm thick) endorectal MRE in a prostate mimicking phantom. The low-amplitude vibrations (± 8-38 μm displacements) necessary to perform endorectal MRE did not affect the signal-to noise ratio of the coil and endorectal MRE was capable of resolving 0.1 cc (0.6 cm diameter) spherical inclusion volumes. Therefore, the results of this study, in combination with current clinical practice, motivate clinical evaluation of endorectal MRE in patients.

Assessment of Hepatic Fibrosis by Magnetic Resonance Elastography in Patients With Sclerosing Cholangitis

Background and aims: PSC-IBD is reported to represent a distinct phenotype of IBD characterized by colitis, rectal sparing and backwash ileitis, but this has so far not been confirmed in large well-phenotyped cohorts. The aim of this study was to assess the IBD phenotype associated with PSC in a large Dutch PSC cohort using endoscopic and histopathological criteria. Methods: PSC cases were identified and ascertained, fulfilling well-established serological, histological and radiological criteria in 30 hospitals in The Netherlands. IBD location was recorded according to the Montreal classification. To assess the occurrence of backwash ileitis a subgroup analysis was performed in 40 cases and 80 ageand sex-matched IBD controls with at least one complete ileocolonoscopy including terminal ileum histology, reviewing 370 endoscopy and pathology reports written between 2001 and 2010. Results: 324 (64%) of a total of 506 PSC patients had coexistent IBD, mainly ulcerative colitis (UC, 72%). 147 (80%) of the PSC-UC patients had a pancolitis, 28 (15%) a left sided colitis and eight (4%) a proctitis. Sixty (95%) PSC-Crohn's disease (CD) patients had an (ileo)colitis and three ileitis only (5%). In the subgroup analysis of 40 PSC-IBD patients twenty-seven (68%) PSC-UC patients were identified, as well as twelve (30%) PSC-CD patients and one (2%) PSC-undetermined IBD patient. Twenty-five (93%) PSC-UC patients had a pancolitis, compared to thirty-three (61%) matched UC patients (p = 0.034). Left sided colitis was seen in seventeen (32%) UC controls and in none of the PSC-UC patients (p = 0.001). Backwash ileitis was seen in only one (4%) PSC-UC patient and in none of the UC controls. Conclusion: PSC-IBD represents a distinct IBD phenotype. The majority of Dutch PSC-UC patients have a pancolitis. In case of PSC-CD, colonic inflammation is involved in 95% of patients. Backwash ileitis is not a prominent finding in Dutch PSC-UC cases.