Diagnostic Accuracy of Two-Dimensional Shear Wave Elastography for Liver Fibrosis: A Multicenter Prospective Study

Assessing liver fibrosis in chronic liver disease: Comparison of diffusion-weighted MR elastography and two-dimensional shear-wave elastography using histopathologic assessment as the reference standard

INTRODUCTION AND OBJECTIVES

Liver stiffness measurement (LSM) by two-dimensional shear-wave elastography (2D SWE) is a well-established method for assessing hepatic fibrosis. Diffusion-weighted imaging (DWI) can be converted into virtual shear modulus (µDiff) to estimate liver elasticity. The purpose of this study was to correlate and compare the diagnostic performance of DWI-based virtual elastography and 2D SWE for staging hepatic fibrosis in patients with chronic liver disease, using histopathologic assessment as the reference standard.

PATIENTS AND METHODS

This retrospective study included 111 patients who underwent preoperative multiple b-value DWI and 2D SWE. The µDiff was calculated using DWI acquisition with b-values of 200 and 1,500 /mm2, and LSM was obtained by 2D SWE. Correlation between µDiff and LSM was assessed, as well as the correlation between these noninvasive methods and histologic fibrosis stages. The diagnostic efficacy of µDiff and LSM for staging liver fibrosis was compared with receiver operating characteristic (ROC) curve analysis.

RESULTS

There was a significant positive correlation between µDiff and LSM (rho= 0.48, P < 0.001). µDiff (rho= 0.54, P < 0.001) and LSM (rho= 0.76, P < 0.001) were positively correlated with liver fibrosis stages. Areas under the curves (AUCs) of µDiff and LSM, respectively, were 0.81 and 0.90 for significant fibrosis, 0.89 and 0.98 for advanced fibrosis, and 0.77 and 0.91 for cirrhosis. The AUCs of 2D SWE for diagnosing advanced fibrosis and cirrhosis were significantly higher than those of µDiff (P < 0.05 for both).

CONCLUSIONS

LSM by 2D SWE yields larger AUCs compared to µDiff obtained from DWI-based virtual elastography for various stages of liver fibrosis. LSM is superior to µDiff in predicting advanced fibrosis and cirrhosis.

Diagnostic performance of shear wave measurement in the detection of hepatic fibrosis: A multicenter prospective study

AIM

This study aimed to establish the shear wave measurement (SWM) cut-off value for each fibrosis stage using magnetic resonance (MR) elastography values as a reference standard.

METHODS

We prospectively analyzed 594 patients with chronic liver disease who underwent SWM and MR elastography. Correlation coefficients (were analyzed, and the diagnostic value was evaluated by the area under the receiver operating characteristic curve. Liver stiffness was categorized by MR elastography as F0 (<2.61 kPa), F1 (≥2.61 kPa, <2.97 kPa, any fibrosis), F2 (≥2.97 kPa, <3.62 kPa, significant fibrosis), F3 (≥3.62 kPa, <4.62 kPa, advanced fibrosis), or F4 (≥4.62 kPa, cirrhosis).

RESULTS

The median SWM values increased significantly with increasing fibrosis stage (p < 0.001). The correlation coefficient between SWM and MR elastography values was 0.793 (95% confidence interval 0.761-0.821). The correlation coefficients between SWM and MR elastography values significantly decreased with increasing body mass index and skin-capsular distance; skin-capsular distance values were associated with significant differences in sensitivity, specificity, accuracy, or positive predictive value, whereas body mass index values were not. The best cut-off values for any fibrosis, significant fibrosis, advanced fibrosis, and cirrhosis were 6.18, 7.09, 8.05, and 10.89 kPa, respectively.

CONCLUSIONS

This multicenter study in a large number of patients established SWM cut-off values for different degrees of fibrosis in chronic liver diseases using MR elastography as a reference standard. It is expected that these cut-off values will be applied to liver diseases in the future.

WFUMB Guideline/Guidance on Liver Multiparametric Ultrasound: Part 1. Update to 2018 Guidelines on Liver Ultrasound Elastography

The World Federation for Ultrasound in Medicine and Biology (WFUMB) endorsed the development of this document on multiparametric ultrasound. Part 1 is an update to the WFUMB Liver Elastography Guidelines Update released in 2018 and provides new evidence on the role of ultrasound elastography in chronic liver disease. The recommendations in this update were made and graded using the Oxford classification, including level of evidence (LoE), grade of recommendation (GoR) and proportion of agreement (Oxford Centre for Evidence-Based Medicine [OCEBM] 2009). The guidelines are clinically oriented, and the role of shear wave elastography in both fibrosis staging and prognostication in different etiologies of liver disease is discussed, highlighting advantages and limitations. A comprehensive section is devoted to the assessment of portal hypertension, with specific recommendations for the interpretation of liver and spleen stiffness measurements in this setting.

Bowel Stiffness Assessed by Shear-Wave Ultrasound Elastography Predicts Disease Behavior Progression in Patients With Crohn's Disease

INTRODUCTION

There is a lack of reliable predictors of disease behavior progression in patients with Crohn's disease (CD). Real-time shear-wave elastography (SWE) is a novel method for evaluating tissue stiffness. However, its value for assessing CD has not yet been investigated. We aimed to explore the value of SWE and other ultrasound parameters at diagnosis in predicting CD behavior progression.

METHODS

We retrospectively collected data from patients with CD with the nonstenotic nonpenetrating disease (B1 phenotype based on the Montreal classification). All patients underwent intestinal ultrasound at baseline and were followed up. The end point was defined as disease behavior progression to stricturing (B2) or penetrating (B3) disease. Cox regression analysis was performed for the association between baseline characteristics and subsequent end points. In addition, a multivariate nomogram was established to predict the risk of disease behavior progression quantitatively.

RESULTS

A total of 130 patients with CD with B1 phenotype were enrolled. Twenty-seven patients (20.8%) developed B2 or B3 disease, with a median follow-up of 33 months. Multivariate analysis identified that SWE was the only independent predictor of disease behavior progression (hazard ratio 1.08, 95% confidence interval 1.03-1.12, P = 0.001). A reverse of the HR appeared at the cutoff 12.75 kPa. The nomogram incorporating SWE and other clinical characteristics showed a good prediction performance (area under the curve = 0.792).

DISCUSSION

Intestinal stiffness assessed using SWE is an independent predictor of disease behavior progression in patients with CD. Patients with CD with SWE >12.75 kPa at diagnosis are prone to progress toward stricturing or penetrating diseases.

Advanced fibrosis leads to overestimation of steatosis with quantitative ultrasound in individuals without hepatic steatosis

PURPOSE

The effect of hepatic fibrosis stage on quantitative ultrasound based on the attenuation coefficient (AC) for liver lipid quantification is controversial. The objective of this study was to determine how the degree of fibrosis assessed by magnetic resonance (MR) elastography affects AC based on the ultrasound-guided attenuation parameter according to the grade of hepatic steatosis, using magnetic resonance imaging (MRI)-derived proton density fat fraction (MRIderived PDFF) as the reference standard.

METHODS

Between February 2020 and April 2021, 982 patients with chronic liver disease who underwent AC and MRI-derived PDFF measurement as well as MR elastography were enrolled. Multiple regression was used to investigate whether AC was affected by the degree of liver stiffness.

RESULTS

AC increased as liver stiffness progressed in 344 patients without hepatic steatosis (P=0.009). In multivariable analysis, AC was positively correlated with skin-capsule distance (P<0.001), MR elastography value (P=0.037), and MRI-derived PDFF (P<0.001) in patients without hepatic steatosis. In 52 of 982 patients (5%), the correlation between AC and MRIderived PDFF fell outside the 95% confidence interval for the regression line slope. Patients with MRI-derived PDFF lower than their AC (n=36) had higher fibrosis-4 scores, albumin-bilirubin scores, and MR elastography values than patients with MRI-derived PDFF greater than their AC (n=16; P=0.018, P=0.001, and P=0.011, respectively).

CONCLUSION

AC is affected by liver fibrosis (MR elastography value ≥6.7 kPa) only in patients without hepatic steatosis (MRI-derived PDFF <5.2%). These values should be interpreted with caution in patients with advanced liver fibrosis.

Noninvasive Tests Used in Risk Stratification of Patients with Nonalcoholic Fatty Liver Disease

As the prevalence of obesity and type 2 diabetes increases around the world, the prevalence of nonalcoholic fatty liver disease (NAFLD) has grown proportionately. Although most patients with NAFLD do not experience progressive liver disease, about 15% to 20% of those with nonalcoholic steatohepatitis can and do progress. Because liver biopsy's role in NAFLD has become increasingly limited, efforts have been undertaken to develop non-invasive tests (NITs) to help identify patients at high risk of progression. The following article discusses the NITs that are available to determine the presence of NAFLD as well as high-risk NAFLD.

Shear wave elastography as a quantitative biomarker of diabetic peripheral neuropathy: A systematic review and meta-analysis

Background

Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes and the strongest initiating risk factor for diabetic foot ulceration. Early diagnosis of DPN through screening measures is, therefore, of great importance for diabetic patients. Recently, shear wave elastography (SWE) has been used as a method that is complementary to neuroelectrophysiological examination in the diagnosis of DPN. We aimed to conduct a meta-analysis based on currently available data to evaluate the performance of tibial nerve stiffness on SWE for diagnosing DPN.

Methods

Both PubMed, EMBASE, the Cochrane Library, and Web of Science were searched for studies that investigated the diagnostic performance of SWE for DPN up to March 1th, 2022. Three measures of diagnostic test performance, including the summary area under receiver operating characteristics curve (AUROC), the summary sensitivity and specificity, and the summary diagnostic odds ratios were used to assess the diagnostic accuracy of SWE. All included studies were published between 2017 and 2021.

Results

Six eligible studies (with 170 DPN patients, 28 clinically defined DPN patients, 168 non-DPN patients, and 154 control participants) that evaluated tibial nerve stiffness were included for meta-analysis. The summary sensitivity and specificity of SWE for tibial nerve stiffness were 75% (95% confidence interval [CI]: 68–80%) and 86% (95% CI: 80–90%), respectively, and the summary AUROC was 0.84 (95% CI: 0.81–0.87), for diagnosing DPN. A subgroup analysis of five two-dimensional SWE studies revealed similar diagnostic performance, showing the summary sensitivity and specificity of 77% (95% CI: 69–83%) and 86% (95% CI: 79–91%), respectively, and a summary AUROC value of 0.86 (95% CI: 0.83–0.89).

Conclusions

SWE is found to have good diagnostic accuracy for detecting DPN and has considerable potential as an important and noninvasive adjunctive tool in the management of patients with DPN.

Diagnosis of significant liver fibrosis in patients with chronic hepatitis B using a deep learning-based data integration network

BACKGROUND AND AIMS

Chronic hepatitis B virus (CHB) infection remains a major global health burden and the non-invasive and accurate diagnosis of significant liver fibrosis (≥ F2) in CHB patients is clinically very important. This study aimed to assess the potential of the joint use of ultrasound images of liver parenchyma, liver stiffness values, and patients' clinical parameters in a deep learning model to improve the diagnosis of ≥ F2 in CHB patients.

METHODS

Of 527 CHB patients who underwent US examination, liver elastography and biopsy, 284 eligible patients were included. We developed a deep learning-based data integration network (DI-Net) to fuse the information of ultrasound images of liver parenchyma, liver stiffness values and patients' clinical parameters for diagnosing ≥ F2 in CHB patients. The performance of DI-Net was cross-validated in a main cohort (n = 155) of the included patients and externally validated in an independent cohort (n = 129), with comparisons against single-source data-based models and other non-invasive methods in terms of the area under the receiver-operating-characteristic curve (AUC).

RESULTS

DI-Net achieved an AUC of 0.943 (95% confidence interval [CI] 0.893-0.973) in the cross-validation, and an AUC of 0.901 (95% CI 0.834-0.945) in the external validation, which were significantly greater than those of the comparative methods (AUC ranges: 0.774-0.877 and 0.741-0.848 for cross- and external validations, respectively, ps < 0.01).

CONCLUSION

The joint use of ultrasound images of liver parenchyma, liver stiffness values, and patients' clinical parameters in a deep learning model could significantly improve the diagnosis of ≥ F2 in CHB patients.

Noninvasive assessment of liver fibrosis and its clinical significance in nonalcoholic fatty liver disease

Liver fibrosis is the most important prognostic factor in patients with nonalcoholic fatty liver disease (NAFLD). Several noninvasive markers for fibrosis, including blood-based markers and imaging based-markers have been developed. Indirect fibrosis markers (e.g., fibrosis-4 index and NAFLD fibrosis score) consist of standard laboratory data and clinical parameters. Given its availability and high negative predictive value for advanced fibrosis, these markers are suitable for screening at primary care. Blood-based fibrogenesis markers (enhanced liver fibrosis and N-terminal propeptide of type 3 collagen), ultrasound-based modalities (vibration-controlled transient elastography, point shear wave elastography [SWE], and two-dimensional SWE), and magnetic resonance elastography have high diagnostic accuracy for liver fibrosis and are suitable for diagnosing liver fibrosis at secondary care centers. Sequential use of these markers can increase diagnostic accuracy and reduce health care costs. Furthermore, combining noninvasive makers may assist in identifying candidates for pharmacological trials and reducing screening failure. Emerging data suggest that these noninvasive markers are associated with liver-related events (hepatocellular carcinoma and decompensation) and mortality. Furthermore, delta change in noninvasive markers over time is also associated with time-course change in fibrosis, liver-related event risk, and mortality risk. However, the association between liver fibrosis and cardiovascular disease (CVD) risk is still controversial. CVD risk may decrease in patients with decompensated liver disease and noninvasive markers may be useful for assessing CVD risk in these patients. Therefore, noninvasive markers may be utilized as measures of fibrosis as well as real-time prognostic tools, in place of liver biopsy.

Longitudinal association of magnetic resonance elastography-associated liver stiffness with complications and mortality

BACKGROUND

Magnetic resonance elastography (MRE) has the highest diagnostic accuracy for liver fibrosis; however, the association between MRE-associated liver stiffness and the development of hepatic and extrahepatic complications as well as mortality remains unclear.

AIM

In this study, we investigated the longitudinal association between MRE-associated liver stiffness and complications and mortality.

METHODS

This retrospective study included 2373 consecutive patients with chronic liver disease. All patients received standard of care and the development of complications was assessed every 1-6 months.

RESULTS

Newly diagnosed hepatocellular carcinoma (HCC), decompensation, major adverse cardiovascular events (MACE), extrahepatic cancer and death were observed in 99, 117, 73, 77 and 170 patients respectively. In multivariable analysis, the adjusted hazard ratios (aHR) (95% confidence interval [CI]) for HCC, decompensation, MACE, extrahepatic cancer and mortality were 1.28 (1.2-1.4), 1.34 (1.3-1.4), 0.96 (0.9-1.1), 1.00 (0.9-1.1) and 1.17 (1.1-1.2), respectively, with each 1-kPa increase in liver stiffness. Similarly, the aHR (95% CI) for HCC, decompensation, MACE, extrahepatic cancer and mortality were 4.20 (2.2-8.2), 67.5 (9.2-492), 0.83 (0.4-1.7), 0.90 (0.5-1.7) and 2.90 (1.6-5.4), respectively, in patients with cirrhosis (>4.7 kPa) compared to those with minimal fibrosis (<3 kPa).

CONCLUSIONS

Increased MRE-associated liver stiffness was associated with increased risk for HCC, decompensation and mortality in a dose-dependent fashion but not with MACE or extrahepatic cancer, implicating a significant role for MRE in liver-related events and mortality; however, further studies are warranted to explore its role in MACE and extrahepatic cancer.