Real-time shear-wave elastography: applicability, reliability and accuracy for clinically significant portal hypertension

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.

Validation of Baveno VII criteria for clinically significant portal hypertension by two-dimensional shear wave elastography

BACKGROUND

The Baveno VII consensus proposed criteria for the non-invasively diagnosis of clinically significant portal hypertension (CSPH) in patients with compensated advanced chronic liver disease (cACLD). The performance of Baveno VII criteria for assessing CSPH by two-dimensional shear wave elastography (2D-SWE) had not been well validated. We aimed to validate the performance of Baveno VII criteria for rule-in and rule-out CSPH by 2D-SWE.

METHOD

This is an international multicenter study including cACLD patients from China and Croatia with paired liver stiffness measurement (LSM), spleen stiffness measurement (SSM) by 2D-SWE, and hepatic venous pressure gradient (HVPG) were included. CSPH was defined as HVPG ≥ 10 mmHg.

RESULT

A total of 146 patients with cACLD were enrolled, and finally 118 patients were included in the analysis. Among them, CSPH was documented in 79 (66.9%) patients. Applying the Baveno VII criteria for rule-out CSPH by 2D-SWE, [LSM ≤ 15 kPa and platelet count ≥ 150 × 109/L] OR SSM < 21 kPa, could exclude CSPH with sensitivity > 90% (93.5 or 98.7%) but negative predictive value < 90% (74.1 or 85.7%). Using the Baveno VII criteria for rule-in CSPH by 2D-SWE, LSM ≥ 25 kPa OR SSM ≥ 50 kPa, could diagnose CSPH with 100% specificity and 100% positive predictive values.

CONCLUSION

Baveno VII criteria by 2D-SWE showed a good diagnostic performance for ruling in but not for ruling out CSPH, which might become an emerging non-invasive elastography tool to select the patients who needed non-selective beta blocker therapy.

Non-Invasive Assessment of Liver Fibrosis in Hepatitis B Patients

The aim of this review is to provide updated information on the clinical use of non-invasive serum and imaging-based tests for fibrosis assessment in chronic hepatitis B (CHB) virus infection. In recent years, non-invasive tests (NIT) have been increasingly used to determine eligibility for treatment. Liver biopsy is still considered the gold standard for assessing inflammatory activity and fibrosis staging, but it is an invasive procedure with inherent limitations. Simple serum markers such as APRI and FIB-4 are limited by indeterminate results but remain useful initial tests for fibrosis severity if imaging elastography is not available. Point-of-care US-based elastography techniques, such as vibration-controlled transient elastography or 2D shear wave elastography, are increasingly available and have better accuracy than simple serum tests for advanced fibrosis or cirrhosis, although stiffness cut-offs are variable based on E-antigen status and inflammatory activity. Current NITs have poor diagnostic performance for following changes in fibrosis with antiviral therapy. However, NITs may have greater clinical utility for determining prognosis in patients with CHB that have advanced disease, especially for the development of hepatocellular carcinoma and/or liver decompensation. Algorithms combining serum and imaging NITs appear promising for advanced fibrosis and prognostic risk stratification.

Possible use of 2D shear wave liver elastography in new-onset ascites evaluation

BACKGROUND

No data on the use of 2D shear wave elastography exists regarding the evaluation of the new-onset ascites causality.

AIMS

To determine whether 2D shear wave elastography can help in the non-invasive assessment of the new-onset ascites cause. To assess the applicability of liver stiffness measured by 2D shear wave elastography using Esaote MyLab Nine apparatus in patients with ascites.

METHODS

In 52 consecutive patients with new-onset ascites (January 2020 to October 2021), liver stiffness using 2D shear wave elastography was prospectively measured. The reliable measurements were used for further analysis. Relevant clinical and laboratory data was collected.

RESULTS

The calculated liver stiffness measurement cut-off value of 14.4 kPa held 94% accuracy, 100% sensitivity, and 83% specificity when determining ascites with serum ascites albumin gradient ≥11 g/L. Reliable 2D shear wave elastography success rate was 84%.

CONCLUSIONS

2D shear wave elastography may potentially be used to differentiate transudative from exudative ascites, especially in patients with portal hypertension and peritoneal carcinomatosis.

A prospective comparison of three ultrasound-based techniques in quantitative diagnosis of hepatic steatosis in NAFLD

PURPOSE

To investigate the correlation between different ultrasound attenuation-based techniques and to compare their diagnostic performances using proton magnetic resonance spectroscopy (1H-MRS) as a reference standard.

METHODS

Participants who had clinical suspicion of nonalcoholic fatty liver disease (NAFLD) were prospectively recruited. Each subject had ultrasound with attenuation imaging (ATI) or quantitative ultrasound including tissue attenuation imaging (TAI) and tissue scatter-distribution imaging (TSI), and controlled-attenuation parameter (CAP) and 1H-MRS if available. The technical success rates, intra-observer repeatabilities of attenuation and backscattering coefficient were evaluated. ATI, TAI and CAP were three attenuation-based techniques. Spearman coefficient was used to test correlations among them and 1H-MRS. In addition, the diagnostic performances of these parameters for detecting ≥ 5% or 10% hepatic steatosis were evaluated.

RESULTS

130 participants had ultrasound scanning. Among them, 67 had CAP and 48 had 1H-MRS. The technical success rates were all 100%. The intra-observer repeatabilities of them were also excellent (ICCs > 0.90) and AC-ATI correlated well with AC-TAI (r = 0.752). AC-ATI, AC-TAI showed moderate correlation with CAP, (rATI = 0.623, 95% CI 0.446-0.752, P < 0.001; rTAI = 0.573, 95% CI 0.377-0.720, P < 0.001). For correlation with 1H-MRS, ATI and TAI performed better than CAP(rATI = 0.587; rTAI = 0.712; r CAP = 0.485). The AUCs of ATI, TAI, TSI and CAP for detecting ≥ 5% hepatic steatosis were 0.883, 0.862, 0.870 and 0.868, respectively. The AUC improved to 0.907 when TAI and TSI were combined (P < 0.05). When detecting ≥ 10% hepatic steatosis, the AUCs were 0.855, 0.702, 0.822 and 0.838, respectively.

CONCLUSION

Different ultrasound attenuation-based techniques were well correlated and exhibited good diagnostic performances in quantitative diagnosis of hepatic steatosis, however, the threshold values were different. Combinations of multiple parameters may improve the diagnostic performance in detecting hepatic steatosis.

TRIAL REGISTRATION

The study has been registered online ( https://www.chictr.org.cn ; unique identifier: ChiCTR2300069459).

EASL-ERN position paper on liver involvement in patients with Fontan-type circulation

Fontan-type surgery is the final step in the sequential palliative surgical treatment of infants born with a univentricular heart. The resulting long-term haemodynamic changes promote liver damage, leading to Fontan-associated liver disease (FALD), in virtually all patients with Fontan circulation. Owing to the lack of a uniform definition of FALD and the competitive risk of other complications developed by Fontan patients, the impact of FALD on the prognosis of these patients is currently debatable. However, based on the increasing number of adult Fontan patients and recent research interest, the European Association for The Study of the Liver and the European Reference Network on Rare Liver Diseases thought a position paper timely. The aims of the current paper are: (1) to provide a clear definition and description of FALD, including clinical, analytical, radiological, haemodynamic, and histological features; (2) to facilitate guidance for staging the liver disease; and (3) to provide evidence- and experience-based recommendations for the management of different clinical scenarios.

Non-invasive Measurement of the Viscoelasticity of the Optic Nerve and Sclera for Assessing Papilledema: A Pilot Clinical Study

OBJECTIVE

The purpose of this study was to evaluate our novel ultrasound vibro-elastography (UVE) technique for assessing patients with papilledema by non-invasively measuring shear wave speed (SWS), elasticity and viscosity properties of the optic nerve and sclera.

METHODS

Shear wave speeds were measured at three frequencies-100, 150 and 200 Hz-on the optic nerve and sclera tissues for assessing patients with papilledema resulting from idiopathic intracranial hypertension (IIH). The method was evaluated in six papilledema patients and six controls on two separate locations for each participant (i.e., optic nerve and posterior sclera). SWSs of the optic nerve and sclera were analyzed by using a 2-D speed map technique within a circular region of interest (ROI) (i.e., the diameter of the ROI was 1.5 mm × 3.0 mm at the optic nerve and sclera, respectively). Elasticity and viscosity were then analyzed using the wave speed dispersion over the three frequencies.

RESULTS

We measured values of SWS at both locations, optic nerve and sclera, of the right eye and left eye at three different frequencies in IIH patients and controls. The SWS (mean ± standard deviation [m/s]) of the right eye was significantly higher at the sclera in IIH patients compared with controls (i.e., patients vs. controls: 5.91 ± 0.54 vs. 3.86 ± 0.56, p < 0.0001 at 100 Hz), but there was no significant difference at the optic nerve (i.e., patients vs. controls: 3.62 ± 0.39 vs. 3.36 ± 0.35, p = 0.1100 at 100Hz). We observed increased elasticity (kPa) in IIH patients, indicating there are significant differences in elasticity between patients and controls at the optic nerve and sclera (i.e., right eye [patients vs. controls]: 14.42 ± 6.59 vs. 6.5 ± 5.71, p = 0.0065 [optic nerve]; 33.04 ± 10.62 vs. 9.16 ± 7.15, p < 0.0001 [sclera]). Viscosity was also (Pa·s) higher in the sclera and optic nerve of the left eye (i.e., left eye [patient vs. control]: 8.89 ± 4.37 vs. 7.27 ± 5.01, p = 0.3790 (optic nerve); 16.05 ± 10.79 vs. 8.49 ± 6.09, p < 0.0194 [sclera]).

CONCLUSION

This research illustrates the feasibility of using our UVE system to evaluate stiffness of different tissues in the eye non-invasively. It suggests that the viscoelasticity of the posterior sclera is higher than that of the optic nerve. We found that the posterior sclera is stiffer than the optic nerve in patients with papilledema resulting from IIH, making UVE a potential non-invasive technique for assessing papilledema.

Accuracy of spleen stiffness measurement for the diagnosis of clinically significant portal hypertension in patients with compensated advanced chronic liver disease: a systematic review and individual patient data meta-analysis

BACKGROUND

The diagnosis of clinically significant portal hypertension is crucial for prognosis and treatment guidance in patients with compensated advanced chronic liver disease (ACLD). Spleen stiffness measurement (SSM) might improve the non-invasive diagnosis of clinically significant portal hypertension, but previous studies have reported heterogeneous SSM cutoffs. We aimed to evaluate the accuracy of SSM and SSM-based algorithms in this setting.

METHODS

In this systematic review and individual patient data meta-analysis, we searched PubMed, Embase, Scopus, Web of Science, and the Cochrane Library from database inception to Dec 31, 2022, for articles, abstracts, and letters, with no restrictions on language. Cross-sectional studies reporting hepatic venous pressure gradient and SSM by different techniques (transient elastography; two-dimensional shear-wave elastography [2D-SWE]; point shear-wave elastography [p-SWE]) in adults (≥18 years) with compensated ACLD were eligible for inclusion. The main outcome was the diagnostic performance of two SSM-based algorithms, with the Baveno VII model as a reference, evaluating sensitivity and specificity, as well as summary negative predictive values (NPVs) and positive predictive values (PPVs). In the Baveno VII model, clinically significant portal hypertension was ruled out if patients had a liver stiffness measurement (LSM) of 15 kPa or less and a platelet count of 150 × 109 platelets per L or higher and ruled in if they had an LSM of greater than 25 kPa. The two SSM-based models combined these same cutoffs with additional criteria. In the Baveno VII-SSM single cutoff model, clinically significant portal hypertension was ruled out if at least two of the following were present: LSM of 15 kPa or less, platelet count of 150 × 109 platelets per L or higher, and SSM of 40 kPa or less; and ruled in if at least two were present: LSM of greater than 25 kPa, platelet count of less than 150 × 109 platelets per L, and SSM of greater than 40 kPa. The Baveno VII-SSM dual cutoff model used the same criteria, but with a cutoff of SSM of less than 21 kPa to rule out, and greater than 50 kPa to rule in, clinically significant portal hypertension. This study is registered with PROSPERO, CRD42019127164.

FINDINGS

Of the 44 records assessed for eligibility, 17 studies (with 1245 patients) were included in the meta-analysis. In the transient elastography cohort (n=600), the Baveno VII algorithm was validated for both ruling out (NPV 100%, 95% CI 64-100; sensitivity 100%, 95% CI 70-100) and ruling in (PPV 95%, 85-98; specificity 94%, 95% CI 87-97) clinically significant portal hypertension, but the proportion of patients with indeterminate results (grey zone) was 48% (95% CI 44-52); 57% (95% CI 52-62) of patients with clinically significant portal hypertension were included in the rule-in zone. The Baveno VII-SSM dual cutoff model had adequate NPV (98%, 95% CI 58-100; sensitivity 100%, 95% CI 91-100) and PPV (93%, 95% CI 84-97; specificity 89%, 95% CI 84-93), with 32% (95% CI 28-36) of patients in the grey zone; 76% (95% CI 72-80) of the patients with clinically significant portal hypertension were in the rule-in zone. The Baveno VII-SSM single cutoff model had a sensitivity of 93% (95% CI 85-97) and a NPV of 85% (95% CI 60-96) for ruling out, and a specificity of 86% (95% CI 80-91) and a PPV of 92% (95% CI 83-95) for ruling in, clinically significant portal hypertension. 88% (95% CI 84-91) of patients with clinically significant portal hypertension were included in the rule-in zone and 9% (95% CI 7-12) of patients were in the grey zone. In the 2D-SWE cohort (n=225), all three algorithms could safely rule in clinically significant portal hypertension with adequate PPV (≥90%), but NPV was inadequate for ruling out clinically significant portal hypertension. Insufficient data were available to evaluate the performance of SSM assessed by p-SWE. Heterogeneity was low (I2<25%) for most estimates.

INTERPRETATION

Algorithms combining Baveno VII criteria with SSM showed good performance and reduced the diagnostic grey zone for clinically significant portal hypertension compared with Baveno VII criteria alone. Future studies should evaluate whether SSM-based diagnosis allows for the identification of patients who would benefit from non-selective β-blocker treatment.

FUNDING

None.

Use of Sound Touch Elastography and Sound Touch Quantification for the Noninvasive Evaluation of Portal Hypertension in a Rat Model

OBJECTIVES

In this study, we used the recently developed ultrasound elastography techniques sound touch elastography (STE) and sound touch quantification (STQ) to quantify portal hypertension (PHT) severity in a rat model of carbon tetrachloride (CCl₄ )-induced cirrhotic PHT.

METHODS

In total, 60 rats were used. Various degrees of PHT were established. Liver and spleen stiffness were measured by STE (L-STE and S-STE, respectively) and STQ (L-STQ and S-STQ, respectively). We measured portal pressure (PP) after ultrasonographic examination. The performance of the STE and STQ parameters in the identification of PHT was evaluated using receiver operating characteristic (ROC) analyses.

RESULTS

Liver and spleen stiffness measurements obtained with STE and STQ correlated positively with the PP (r = 0.566-0.882, all P < .001). The areas under ROC curves for L-STE, S-STE, L-STQ, and S-STQ values were 0.931 (95% confidence interval [CI], 0.847-1.000), 0.982 (95% CI, 0.956-1.000), 0.796 (95% CI, 0.680-0.912), and 0.925 (95% CI, 0.858-0.993), respectively, for PP ≥5 mmHg; 0.937 (95% CI, 0.865-1.000), 0.938 (95% CI, 0.864-1.000), 0.967 (95% CI, 0.923-1.000), and 0.960 (95% CI, 0.897-1.000), respectively, for PP ≥10 mmHg; and 0.954 (95% CI, 0.897-1.000), 0.790 (95% CI, 0.652-0.928), 0.808 (95% CI, 0.680-0.935), and 0.740 (95% CI, 0.595-0.885), respectively, for PP ≥12 mmHg.

CONCLUSIONS

STE and STQ are reliable noninvasive tools for the assessment of PHT severity, especially for PP ≥10 mmHg, in a rat model of CCl₄ -induced cirrhotic PHT.

Validation of the Baveno VI criteria to rule out high-risk varices using hepatic shear-wave elastography

INTRODUCTION AND OBJECTIVES

Liver stiffness measurement (LSM) by transient elastography has been validated to predict high-risk varices (HRV). We aimed to evaluate the accuracy of shear-wave elastography (SWE) and platelet count (Baveno VI criteria) to rule out HRV in patients with compensated advanced chronic liver disease (c-ACLD).

METHODS

This retrospective study analyzed data of patients with c-ACLD (transient elastography ≥ 10 kPa) submitted to two-dimensional SWE (2D-SWE) (GE-LOGIQ-S8) and/or point SWE (p-SWE) (ElastPQ) who had a gastrointestinal endoscopy within 24 months. HRV definition was a large size and presence of red wale marks or sequelae from previous treatment. Optimal thresholds of SWE systems for HRV were identified. The proportion of spared gastrointestinal endoscopies and missing HRV considering a favorable SWE Baveno VI criteria were assessed.

RESULTS

Eighty patients [36% male, median age = 63 (interquartile range, 57-69) years] were included. The prevalence of HRV was 34% ( n  = 27/80). The optimal thresholds to predict HRV were 10 kPa and 12 kPa for 2D-SWE and p-SWE, respectively. A favorable 2D-SWE Baveno VI criteria (LSM < 10 kPa and platelets count > 150 × 10 9 /mm 3 ) avoided 19% of gastrointestinal endoscopies without missing HRVs. A favorable p-SWE Baveno VI criteria (LSM < 12 kPa and platelets count > 150 × 10 9 /mm 3 ) spared 20% of gastrointestinal endoscopy without missing HRVs. Using a lower threshold of platelet count (<110 × 10 9 /mm 3 , expanded Baveno VI), 2D-SWE (<10 kPa) avoided 33% of gastrointestinal endoscopy with 8% of missing HRVs, while p-SWE (<12 kPa) avoided 36% of gastrointestinal endoscopy with 5% of missing HRVs.

CONCLUSION

LSM by p-SWE or 2D-SWE combined with platelet count (Baveno VI criteria) can spare a considerable number of gastrointestinal endoscopies missing a negligible proportion of HRV.

How to Identify Advanced Fibrosis in Adult Patients with Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH) Using Ultrasound Elastography-A Review of the Literature and Proposed Multistep Approach

Non-alcoholic fatty liver disease (NAFLD), and its progressive form, non-alcoholic steatohepatitis (NASH), represent, nowadays, real challenges for the healthcare system. Liver fibrosis is the most important prognostic factor for NAFLD, and advanced fibrosis is associated with higher liver-related mortality rates. Therefore, the key issues in NAFLD are the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis. We critically reviewed the ultrasound (US) elastography techniques for the quantitative characterization of fibrosis, steatosis, and inflammation in NAFLD and NASH, with a specific focus on how to differentiate advanced fibrosis in adult patients. Vibration-controlled transient elastography (VCTE) is still the most utilized and validated elastography method for liver fibrosis assessment. The recently developed point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) techniques that use multiparametric approaches could bring essential improvements to diagnosis and risk stratification.

Spleen stiffness can predict liver decompensation and survival in patients with cirrhosis

BACKGROUND AND AIM

Liver stiffness measurement (LSM) has been predicting liver decompensation and survival in cirrhotics. The aim of our study was to investigate if spleen stiffness measurement (SSM) by 2D shear-wave elastography could predict better the probability of decompensation and mortality, compared with LSM and other parameters.

METHODS

Consecutive cirrhotic patients were recruited between 1/2017 and 12/2021. LSM and SSM were performed at baseline and epidemiological, clinical, and laboratory data were collected. Clinical events were recorded every 3 months.

RESULTS

Totally, 177 patients were followed for a mean period of 31 ± 18 months. In Cox regression analysis, only SSM was independently associated with the probability of decompensation (HR: 1.063, 95% CI: 1.009-1.120; P = 0.021), offering an AUROC of 0.710 (P = 0.003) for predicting 1-year liver decompensation (NPV: 81.1% for the cut-off point of 37 kPa). The occurrence of death/liver transplantation was independently associated only with higher SSM (HR: 1.043; 95% CI:1.003-1.084; P = 0.034). The AUROC of SSM for predicting 1-year death/liver transplantation was 0.72 (P = 0.006) (NPV: 95% for the cut-off of 38.8 kPa). The performance of SSM to predict the 1-year death/liver transplantation increased in high-risk patients (CTP: B/C plus MELD >10 plus LSM > 20 kPa), giving an AUROC of 0.80 (P < 0.001). Only 1/26 high-risk patients with SSM < 38.8 kPa died during the first year of follow-up (NPV: 96.4%).

CONCLUSIONS

SSM was the only factor independently associated with the probability of decompensation and occurrence of death, showing better diagnostic accuracy for the prediction of 1-year decompensation or death compared with LSM and MELD score.

Diagnostic accuracy of liver stiffness on two-dimensional shear wave elastography for detecting clinically significant portal hypertension: a meta-analysis

PURPOSE

Two-dimensional shear wave elastography (2D-SWE) has recently been proposed to detect clinically significant portal hypertension (CSPH), we aimed to perform a meta-analysis based on the published data to assess the diagnostic accuracy of 2D-SWE for detecting CSPH.

METHOD

Literature databases were searched up until 1 August 2021. The summary area under receiver operating characteristics curve (AUROC), the summary diagnostic odds ratio (DOR), and the summary sensitivity and specificity were used to examine the accuracy of 2D-SWE for evaluating CSPH. Heterogeneity was explored using meta-regression.

RESULTS

Finally 9 studies with 956 patients were included in this study for evaluation and meta-analysis. 2D-SWE showed good diagnostic performance for detecting CSPH with a summary sensitivity of 83% (95% confidence interval [CI]: 76%-88%) and summary specificity of 78% (95% CI: 65%-87%); the summary AUROC was 0.88 (95% CI: 0.84-0.90). Summary positive likelihood ratio (LR), negative LR, and DOR of 2D-SWE for detecting CSPH were 3.7 (95% CI: 2.4-5.9), 0.22 (95% CI: 0.16-0.30), and 17 (95% CI: 10-29), respectively.

CONCLUSIONS

2D-SWE showed good performance in diagnosing CSPH and can be considered as an important and noninvasive adjunctive approach in the management of patients with CSPH.

Spleen stiffness: a predictive factor of dismal prognosis in liver cirrhosis

Portal hypertension (PH) is a major complication of liver cirrhosis, as it predisposes to the development of serious clinical manifestations such as ascites, hepatic encephalopathy and variceal bleeding, aggravating the prognosis of patients. Hepatic vein pressure gradient (HVPG) is considered the reference method for the estimation of the presence and severity of PH, but this procedure is available only in specialized centers. Alternatively, many non-invasive methods have been proposed in order to substitute HVPG. Among them, liver stiffness measurement (LSM) has been widely used, as it has been shown to correlate well with HVPG, though this relationship seems to weaken in values of HVPG higher than 12 mmHg, the threshold of serious complications development. Several studies supported the use of spleen stiffness measurement (SSM) instead of LSM, anticipating to a more adequate assessment of this advanced stage of PH. The aim of this paper is to critically appraise and summarize the literature about the role of SSM as a predictive tool of liver decompensation and prognosis, highlighting the strengths and the potential limitations of the studies published so far. EXPERT'S OPINION: The utility of SSM in ruling out high risk for bleeding varices in cirrhotic patients has been demonstrated, driving the Baveno VII consensus to encompass SSM in its last recommendations, though its use in patients with non-viral cirrhosis remains to be validated. We believe that in the near future, SSM alone or combined with other tests, will being used not only for sparing upper endoscopies, but also for predicting decompensation and prognosis in advanced compensated cirrhotic patients, regardless of liver disease's etiology. Herein, we present the data that support this consideration, pointing out these issues that should further be investigated in order to elucidate and intensify the value of SSM in the management of patients with liver cirrhosis.

Evaluation of Spleen Stiffness Using Point Shear Wave Elastography in Healthy Individuals

Aim: Sonoelastography is a non-invasive imaging method used to evaluate the mechanical properties of any tissue. The clinical value of method, the usage of which is increasingly prevailing, is gradually increasing and on account of having newly entered the application field, it is becoming a potential in the research area. Shear wave (SW) propagates faster in stiffer and lower elastic tissues. Studies on liver fibrosis musculoskeletal, breast, prostate, testis, and thyroid nodules accept this principle. In this study, aimed to determine the average values using the point shear wave elastography (pSWE) technique in normal healthy individuals and to determine the relationship of these values with age, gender, body mass index (BMI), and the spleen dimensions.Method: In 2019, patients who had visited the internal medicine service and those who have been directed to this clinics for grayscale ultrasound (US) for various reasons are voluntarily included in the study. The research was carried out consecutively on the same day by two specialist doctors who had 10 and 15 years of experience in ultrasonography and 3-year experience in elastography.Results: 39 (39%) of the 100 patients who participated in the study were men, and 61 (61%) were women. And the ages varied between 32-75 years (y) (54,5±9,5). The average spleen stiffness was found to be 89,2±43,3 kilopascal (kPa) (14,2-152,3) by the first observer and 89,4±41,1 kPa (14,4-151,1) by the second observer.Conclusion: To facilitate the common clinical usage and to evaluate the change in the stiffness of the spleen in different patients, first of all, it is required to determine the normal values of the stiffness of the spleen in healthy individuals using sonoelastography. In this study, the average spleen parenchyma stiffness was detected as higher than in previous studies. The values obtained in this study can be used to function as a comparison to determine the spleen stiffness. They can be used as referential to examine the different spleen pathologies in the clinical environments that use Esaote myLab device and pSWE method.

Liver Elastography in Healthy Children Using Three Different Systems - How Many Measurements Are Necessary?

PURPOSE

 Liver elastography is increasingly being applied in screening for and follow-up of pediatric liver disease, and has been shown to correlate well with fibrosis staging through liver biopsy. Because time is of the essence when examining children, we wanted to evaluate if a reliable result can be achieved with fewer acquisitions.

MATERIALS AND METHODS

 243 healthy children aged 4-17 years were examined after three hours of fasting. Participants were divided into four age groups: 4-7 years; 8-11 years; 12-14 years and 15-17 years. Both two-dimensional shear wave elastography (2D-SWE; GE Logiq E9) and point shear wave elastography (pSWE; Samsung RS80A with Prestige) were performed in all participants, while transient elastography (TE, Fibroscan) was performed in a subset of 87 children aged 8-17 years. Median liver stiffness measurement (LSM) values of 3, 4, 5, 6, 7, and 8 acquisitions were compared with the median value of 10 acquisitions (reference standard). Comparison was performed for all participants together as well as within every specific age group. We investigated both the intraclass correlation coefficient (ICC) with absolute agreement and all outliers more than 10 %, 20 % or ≥ 0.5 or 1.0 kPa from the median of 10 acquisitions.

RESULTS

 For all three systems there was no significant difference between three and ten acquisitions, with ICCs ≥ 0.97. All systems needed 4 acquisitions to achieve no LSM deviating ≥ 1.0 kPa of a median of ten. To achieve no LSM deviating ≥ 20 % of a median of ten acquisitions, pSWE and TE needed 4 acquisitions, while 2D-SWE required 6 acquisitions.

CONCLUSION

 Our results contradict recommendations of 10 acquisitions for pSWE and TE and only 3 for 2D-SWE.

Non-invasive diagnosis and follow-up of portal hypertension

Compensated advanced chronic liver disease (cACLD) describes the spectrum of advanced fibrosis/cirrhosis in asymptomatic patients at risk of developing clinically significant portal hypertension (CSPH, defined by a hepatic venous pressure gradient (HVPG) ≥10 mmHg). Patients with cACLD are at high risk of liver-related morbidity and mortality. In patients at risk of chronic liver disease, cACLD is strongly suggested by a liver stiffness (LSM) value >15 kPa or clinical/biological/radiological signs of portal hypertension, and ruled out by LSM <10 kPa, or Fibrotest® ≤0.58, or Fibrometer® ≤0.786. Patients with chronic liver disease (excluding vascular diseases) with a LSM <10 kPa are at low risk of developing portal hypertension complications. The presence of CSPH can be strongly suspected when LSM is ≥20 kPa. In a patient without clinical, endoscopic or radiological features of portal hypertension, measurement of the HVPG is recommended before major liver or intra-abdominal surgery, before extra-hepatic transplantation and in patients with unexplained ascites. Endoscopic screening for oesophageal varices can be avoided in patients with LSM <20 kPa and a platelet count >150 G/L (favourable Baveno VI criteria) at the time of diagnosis. There is no non-invasive method alternative for oeso-gastroduodenal endoscopy in patients with unfavourable Baveno criteria (liver stiffness ≥20 kPa or platelet count ≤50 G/l). Platelet count and liver stiffness measurements must be performed once a year in patients with cACLD with favourable Baveno VI criteria at the time of diagnosis. A screening oeso-gastroduodenal endoscopy is recommended if Baveno VI criteria become unfavourable.

Spleen and Liver Stiffness Evaluation by ARFI Imaging: A Reliable Tool for a Short-Term Monitoring of Portal Hypertension?

BACKGROUND

Assessment of hepatic venous pressure gradient (HVPG) is the most reliable, though invasive method for evaluation of portal hypertension. Non-invasive, elastography-based techniques are well established in diagnosis, but not in monitoring of portal hypertension. The aim of our prospective study was to determine the value of acoustic radiation force impulse (ARFI) elastography technique of the liver and spleen in diagnosis and monitoring of portal hypertension.

METHODS

We prospectively assessed portal hypertension by HVPG and corresponding elastography of the liver and spleen in 31 patients with liver cirrhosis and an indication for primary prophylaxis by non-cardio selective beta-blockers. Investigations were performed at baseline and a follow-up visit after 6-8 weeks. To address the known large variability of values for spleen elastography, well-defined corresponding areas in the spleen were used for baseline and follow-up elastography. Sensitivity, specificity, and AUC-ROC values for both spleen and liver elastography monitoring of portal hypertension were calculated.

RESULTS

Liver but not spleen elastography significantly correlated with HVPG results and was suitable for initial evaluation of portal hypertension. However, changes in HVPG results did not show any correlation with alterations of ARFI values from baseline to follow-up visits both for liver and spleen elastography. Spleen stiffness results were not homogeneous across the whole organ differing significantly between the upper, hilar, and bottom placed investigation areas.

CONCLUSIONS

In this prospective study ARFI-based assessment of liver elastography showed itself suitable for initial assessment but not for monitoring of portal hypertension. Spleen elastography was not appropriate for both, evaluation and monitoring of portal hypertension. A possible explanation for this new data that are in some contrast to previously published results is the degree of portal hypertension in our study, a comparatively short follow-up period, and well-defined investigation areas for spleen elastography in repetitive ARFI investigations. This trial is registered with NCT03315767.

Mastering Core Recommendations during HEPAtology ROUNDS in Patients with Advanced Chronic Liver Disease

Efficient and thorough care of hospitalized patients with advanced chronic liver disease is of utter importance to improve outcomes and optimize quality of life. This requires understanding current evidence and best practices. To facilitate focus on up-to-date knowledge and a practical approach, we have created the HEPA-ROUNDS mnemonic while outlining a practical review of the literature with critical appraisal for the busy clinician. The HEPA-ROUNDS mnemonic provides a structured approach that incorporates critical concepts in terms of prevention, management, and prognostication of the most common complications frequently encountered in patients with advanced chronic liver disease. In addition, implementing the HEPA-ROUNDS mnemonic can facilitate education for trainees and staff caring for patients with advanced chronic liver disease.

Network Meta-Analysis: Noninvasive Imaging Modalities for Identifying Clinically Significant Portal Hypertension

BACKGROUND

Although measurement of the hepatic venous pressure gradient (HVPG) is the current reference standard for obtaining portal venous pressures, several noninvasive imaging-based modalities have been proposed as alternatives.

AIMS

We performed a systematic review and meta-analysis to compare the diagnostic accuracy of noninvasive imaging approaches for identifying clinically significant portal hypertension (CSPH).

METHODS

Two independent reviewers conducted a literature search of PubMed, SCOPUS, and the Cochrane Library from inception until January 5, 2021. The following imaging modalities were compared to HVPG: computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance elastography, ultrasound, transient elastography (TE), shear wave elastography (SWE), acoustic radiation force impulse (ARFI) imaging, contrast-enhanced ultrasound (CEUS), and subharmonic-aided pressure estimation (SHAPE). Sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) for summary receiver operating characteristic were calculated using both frequentist random effects and Bayesian network meta-analytic approaches.

RESULTS

We analyzed 45 studies of 5678 patients. A broad overlapping confidence interval (CI) of DOR was observed among different imaging modalities: ARFI (30.5; 95% CI 12.7-73.3), CEUS and SHAPE (21.1; 95% CI 6.4-69.8), TE of liver stiffness (21.1; 95% CI 13.3-33.5), CT and MRI (13.7; 95% CI 7.40-25.4), SWE of liver stiffness (10.5; 95% CI 5.2-21.1), and ultrasound (9.5; 95% CI 4.9-18.4). The AUC of all imaging methods exceeded 0.8, indicating very good performance. At a cutoff of 80% specificity, TE, CEUS, and SHAPE exceeded 80% sensitivity.

CONCLUSION

Overall, noninvasive imaging modalities perform well for identifying CSPH. Clinicians should consider these noninvasive and cost-efficient tests when diagnosing CSPH.

MR elastography outperforms shear wave elastography for the diagnosis of clinically significant portal hypertension

OBJECTIVES

Portal hypertension (PH) is associated with complications such as ascites and esophageal varices and is typically diagnosed through invasive hepatic venous pressure gradient (HVPG) measurement, which is not widely available. In this study, we aim to assess the diagnostic performance of 2D/3D MR elastography (MRE) and shear wave elastography (SWE) measures of liver and spleen stiffness (LS and SS) and spleen volume, to noninvasively diagnose clinically significant portal hypertension (CSPH) using HVPG measurement as the reference.

METHODS

In this prospective study, patients with liver disease underwent 2D/3D MRE and SWE of the liver and spleen, as well as HVPG measurement. The correlation between MRE/SWE measures of LS/SS and spleen volume with HVPG was assessed. ROC analysis was used to determine the utility of MRE, SWE, and spleen volume for diagnosing CSPH.

RESULTS

Thirty-six patients (M/F 22/14, mean age 55 ± 14 years) were included. Of the evaluated parameters, 3D MRE SS had the strongest correlation with HVPG (r = 0.686, p < 0.001), followed by 2D MRE SS (r = 0.476, p = 0.004). 3D MRE SS displayed the best performance for diagnosis of CSPH (AUC = 0.911) followed by 2D MRE SS (AUC = 0.845) and 3D MRE LS (AUC = 0.804). SWE SS showed poor performance for diagnosis of CSPH (AUC = 0.583) while spleen volume was a fair predictor (AUC = 0.738). 3D MRE SS was significantly superior to SWE LS/SS (p ≤ 0.021) for the diagnosis of CSPH.

CONCLUSION

SS measured with 3D MRE outperforms SWE for the diagnosis of CSPH. SS appears to be a useful biomarker for assessing PH severity. These results need further validation.

KEY POINTS

• Spleen stiffness measured with 2D and 3D MR elastography correlates significantly with hepatic venous pressure gradient measurement. • Spleen stiffness measured with 3D MR elastography demonstrates excellent performance for the diagnosis of clinically significant portal hypertension (AUC 0.911). • Spleen stiffness measured with 3D MR elastography outperforms liver and spleen stiffness measured with shear wave elastography for diagnosis of clinically significant portal hypertension.

Assessment of clinically significant portal hypertension by two-dimensional shear wave elastography

BACKGROUND AND AIMS

To evaluate two-dimensional shear wave elastography (2DSWE) in parallel with transient elastography (TE) for diagnosing clinically significant portal hypertension (CSPH) and high-risk varices (HRV) in patients with chronic liver disease.

PATIENTS AND METHODS

Consecutive patients with suspicion of compensated advanced chronic liver disease (cACLD) [liver stiffness measurement (LSM) ≥ 10 kPa by TE, or morphological signs suggestive of cACLD on imaging], with no history of liver decompensation, underwent hepatic venous pressure gradient (HVPG) measurement, transjugular liver biopsy and esophagogastroduodenoscopy, which served as the reference methods for diagnosing CSPH, cACLD and HRV. All patients underwent LSM and spleen stiffness measurements (SSM) by 2DSWE and TE.

RESULTS

Seventy-six (76) patients were included (78% men, mean age 62 years, body mass index 28.3 kg/m² , 36.8% alcoholic, 30.3% non-alcoholic fatty liver disease, 14.5% viral hepatitis). Of them, 80.3%, 69.7%, 52.6% and 22.4% had cACLD, cirrhosis, CSPH and HRV respectively. LSM performed better than SSM in diagnosing CSPH and HRV. For CSPH, AUROCs (0.926 vs. 0.866), optimal cut-offs (20.1 vs. 20.2 kPa) and sensitivity/specificity (80.5%/94.3% vs. 77.5% /86.1%) were comparable for 2DSWE and TE. Ruling-out of CSPH by 2DSWE (LSM at cut-off with ≥90% sensitivity (13.5 kPa) and platelets ≥ 150 x 10⁹ /L) performed comparably to TE, with 1/24 cases falsely classified as negative. For HRV, AUROCs were similar (0.875 2DSWE, 0.851 TE) with similar optimal LSM cut-offs enabling 100% sensitivity and ruling-out HRV.

CONCLUSION

Liver stiffness measurement by 2DSWE appears to perform equally well as TE for diagnosing CSPH and ruling-out HRV in compensated chronic liver disease.

Can Location of Stiffness Measurement Impact Spleen 2-Dimensional Shear Wave Elastography Measurement?

ABSTRACT

Ultrasound-based spleen elastography is a promising surrogate to predict portal hypertension noninvasively. In contrast to defined standards for liver stiffness measurement, the standardized examination procedures for 2-dimensional (2D) shear wave elastography spleen elastography have not been established yet. The aim was to investigate the impact of location of stiffness measurement on 2D shear wave elastography spleen stiffness measurement (SSM). Patients with splenomegaly were enrolled. Both B-mode ultrasound and elastography of spleen were performed. For SSM, 3 regions were chosen for spleen measurement: lower pole region, central region, and the region between lower pole and center. Mean SSM value, success rate, and reliability predicators (standard deviation, standard deviation/mean, size of region of interest) were assessed. A total of 124 patients were included. For mean SSM value, there were no significant differences among 3 regions. Spleen stiffness measurement success rate in lower pole region, central region, and the region between them was 63.7% (79), 91.1% (113), and 78.2% (97), respectively. The success rate in the central region was significantly higher than that in the other 2 regions (P < 0.05). Reliability in the central region was also highest among the 3 regions. Location of stiffness measurement has a limited effect on SSM. Changing location of measurement will not influence mean stiffness value in spleen.

The Value of Liver and Spleen Stiffness for Evaluation of Portal Hypertension in Compensated Cirrhosis

Patients with compensated advanced chronic liver disease who develop clinically significant portal hypertension (CSPH) are at high risk for hepatic decompensation and mortality if left untreated. Liver biopsy and hepatic venous pressure gradient (HVPG) measurements are the current gold standard procedures for determining fibrosis severity and diagnosing CSPH, respectively; however, both are invasive, limiting their use in clinical practice and larger trials of novel agents. As such, there is an unmet clinical need for reliable, validated, noninvasive measures to detect CSPH and to further assess portal hypertension (PH) severity. Alterations in the biomechanical properties of the liver or spleen in patients with cirrhosis can be quantified by tissue elastography, which examines the elastic behavior of tissue after a force has been applied. A variety of methods are available, including magnetic resonance elastography, shear-wave elastography, and the most thoroughly investigated measure, vibration-controlled transient elastography. Liver stiffness (LS) and spleen stiffness (SS) measurements offer valuable alternatives to detect and monitor CSPH. Both LS and SS correlate well with HVPG, with thresholds of LS >20-25 kPa and SS >40-45 kPa indicating a high likelihood of CSPH. Because SS is a direct and dynamic surrogate of portal pressure, it has the potential to monitor PH severity and assess PH improvement as a surrogate marker for clinical outcomes. Importantly, SS seems to be superior to LS for monitoring treatment response in clinical trials focusing on reducing PH.

Noninvasive assessment oesophageal varices: impact of the Baveno VI criteria

PURPOSE OF REVIEW

In 2015, as a consequence of the high development in noninvasive tests, Baveno VI consensus recommended for the first time the use of a prediction rule (liver stiffness <20kPa and platelet count > 150000) to identify patients at low risk of having varices and that could circumvent endoscopy. These became known as the Baveno VI criteria. We review here the data validating Baveno VI criteria and we discuss the attempts of expanding these criteria.

RECENT FINDINGS

We report 28 studies assessing the performance of Baveno VI criteria showing a pooled 99% negative predictive value for ruling out high-risk varices. Performance is not affected by the cause of cirrhosis. Different attempts at expanding these criteria show suboptimal performance. Nonelastography-based criteria require further validation.

SUMMARY

Baveno VI criteria can be safely used to avoid endoscopy in a substantial proportion of patients with compensated cirrhosis. The progressive change in approach to the management of compensated cirrhosis, progressively focusing on treating portal hypertension with beta-blockers independently of the presence of varices, might render these criteria less relevant.

Detection of liver and spleen stiffness in rats with portal hypertension by two-dimensional shear wave elastography

BACKGROUND

The measurement of liver stiffness (LS) and spleen stiffness (SS) based on ultrasound elastography can be used for non-invasive assessment of portal hypertension (PH). However, there are few studies on the corresponding mechanism of increased spleen stiffness. Our aim was to use two-dimensional shear wave elastrography (2D-SWE) to evaluate the relationship between LS and SS and the severity of PH in rats. And explore the mechanism of the increase of LS and SS in PH.

METHODS

Sixty male Sprague-Dawley rats were randomly divided into portal hypertension (PH group, n = 45) and normal control (NC group, n = 15). At 12 weeks, LS and SS was detected by 2D-SWE in vivo. Related hemodynamic parameters and portal vein pressure (PVP) was measured. Spleen and liver 2D-SWE detection was performed again after sacrifice. Pathological changes were observed.

RESULTS

The SS and LS were increased in PH group (P < 0.05). The SS decreased after sacrifice, and what's more the magnitude of SS decline significantly higher in PH group than in NC group (P < 0.05). The correlation between SS and PVP is stronger than LS (r = 0.624, P < 0.001). SS has positive correlation with indexes of hyperdynamic circulation, but LS was weakly. The correlation between SS and the pathological grade (r = 0.633, P < 0.001) was lower than that in LS (r = 0.905, P < 0.001). Multiple linear regression analysis revealed that SS, portal vein inner diameter (PVD) and splenic vein blood flow velocity (SVV) were significantly associated with PH.

CONCLUSIONS

Spleen and liver measurement by 2D-SWE may be helpful in evaluating PVP. The correlation between SS and PVP is stronger than LS in rats measured by 2D-SWE. Hemodynamic circulation are important in the elevation of SS with portal hypertension. Pathological changes also have a degree of influence, but have more significance for the elevation of LS. SS may be a more effective noninvasive predictor of PH than LS.

Doppler hemodynamic liver index and hepatic elastic modulus: Advanced ultrasonographic techniques for non-invasive prediction of esophageal varices in cirrhosis

PURPOSE

Currently esophagoscopy is the gold standard for assessment of esophageal varices in cirrhosis. Predicting the presence of esophageal varices, varices needing treatment (VNT) and variceal grade by advanced ultrasonographic techniques using a combination of Doppler hemodynamic liver index (HDLI) (quantifying portal hypertension) and hepatic elastic modulus (quantifying hepatic fibrosis) would be a cost-effective and non-invasive alternative to routine endoscopy.

METHODS

Our cross-sectional study consisted of cirrhotic patients diagnosed using clinical features and laboratory parameters. Portal venous Doppler and liver sonoelastography were performed in selected subjects for obtaining measurements of HDLI (portal vein diameter/mean velocity) and hepatic elastic modulus respectively. Within 3 days of ultrasound, the subjects underwent upper GI endoscopy for assessment of presence, VNT and grade (F1, F2, F3) of varices. Subjects were divided into two groups (without and with varices) and data analyzed using XLSTAT.

RESULTS

A total of 60 subjects (26 without and 34 with varices) were evaluated. Mean Doppler HDLI of subjects with varices was significantly higher (0.72 vs. 0.59, p < 0.0001) with progressive increase in values with variceal grade, being highest in grade-F3 (mean 0.77). Likewise, mean hepatic elastic modulus was also higher in subjects with varices (28.9 vs. 12.6 kPa, p < 0.0001) and showed progressive increase with grade (51.1 kPa for F3). For predicting presence of varices, maximum accuracy of elastic modulus was at cut-off of 14.5 kPa (sensitivity, specificity 83% and 84.6%) and Doppler HDLI was at 0.66 (66% and 92.3%). Good inter-rater agreement was present (κ 0.66).

CONCLUSION

Combination of Doppler HDLI and hepatic elastic modulus is an excellent non-invasive method for predicting the presence, VNT, and variceal grade and may obviate need for routine endoscopic screening in cirrhosis.

Liver stiffness assessed by real-time two-dimensional shear wave elastography predicts hypersplenism in patients with Wilson's disease: a prospective study

Background

The current study aimed to explore the value of liver stiffness assessed by two-dimensional real-time shear wave elastography (2D-SWE) to predict hypersplenism occurrence in Wilson’s disease (WD) patients.

Methods

Ninety WD patients were enrolled in this prospective study between May 2018 and December 2018. Baseline clinical data and ultrasound imaging including 2D-SWE liver stiffness of WD patients were collected. After enrollment, patients had follow-ups for 24 months or until they developed hypersplenism. The hypersplenism risk factors were determined using Cox regressions and receiver operating characteristic curves (ROC).

Results

Twenty-nine (32.2%) patients developed hypersplenism. Age, portal vein diameter, and liver stiffness were independent hypersplenism risk factors in WD patients. The cutoff value of liver stiffness to predict hypersplenism was 10.45 kPa, with sensitivity and specificity of 75.9% and 73.8%, respectively. Patients were divided into two groups according to liver stiffness: ≥ 10.45 kPa (57.9% with hypersplenism) or < 10.45 kPa (13.5% with hypersplenism). The median time between enrollment and hypersplenism development was 15 months vs. 22 months (p < 0.001) for the two groups, respectively.

Conclusion

The measurement of liver stiffness by 2D-SWE can be a reliable hypersplenism predictor in WD patients. Therefore, dynamic monitoring of WD patients using 2D-SWE is crucial for the early diagnosis of hypersplenism.

Two-dimensional shear wave elastography predicts survival in advanced chronic liver disease

OBJECTIVE

Liver stiffness measurement (LSM) is a tool used to screen for significant fibrosis and portal hypertension. The aim of this retrospective multicentre study was to develop an easy tool using LSM for clinical outcomes in advanced chronic liver disease (ACLD) patients.

DESIGN

This international multicentre cohort study included a derivation ACLD patient cohort with valid two-dimensional shear wave elastography (2D-SWE) results. Clinical and laboratory parameters at baseline and during follow-up were recorded. LSM by transient elastography (TE) was also recorded if available. The primary outcome was overall mortality. The secondary outcome was the development of first/further decompensation.

RESULTS

After screening 2148 patients (16 centres), 1827 patients (55 years, 62.4% men) were included in the 2D-SWE cohort, with median liver SWE (L-SWE) 11.8 kPa and a model for end stage liver disease (MELD) score of 8. Combination of MELD score and L-SWE predict independently of mortality (AUC 0.8). L-SWE cut-off at ≥20 kPa combined with MELD ≥10 could stratify the risk of mortality and first/further decompensation in ACLD patients. The 2-year mortality and decompensation rates were 36.9% and 61.8%, respectively, in the 305 (18.3%) high-risk patients (with L-SWE ≥20 kPa and MELD ≥10), while in the 944 (56.6%) low-risk patients, these were 1.1% and 3.5%, respectively. Importantly, this M10LS20 algorithm was validated by TE-based LSM and in an additional cohort of 119 patients with valid point shear SWE-LSM.

CONCLUSION

The M10LS20 algorithm allows risk stratification of patients with ACLD. Patients with L-SWE ≥20 kPa and MELD ≥10 should be followed closely and receive intensified care, while patients with low risk may be managed at longer intervals.

Quality criteria for the measurement of liver stiffness

Liver elastography offers the possibility of a quick, non-invasive, and painless evaluation of the liver with immediate results at bedside. Transient elastography is the most validated technology, and many others such as point shear wave elastography, 2D-shear wave elastography, or magnetic resonance elastography have been developed. To ensure the best evaluation, several conditions of examination must be respected for liver stiffness measurement. Indeed, patient, operator and examination characteristics have all been shown to influence the result of liver stiffness measurement. Food intake increases liver stiffness, whereas withdrawal in alcoholics is associated with a decrease in elastography results. Inter-observer reproducibility of the measurement seems suboptimal, and the influence of the operator experience is still being debated. The measurement site and the FibroScan® probe must be correctly chosen. Finally, the intrinsic characteristics and quality criteria of the measurement, especially the interquartile range/median ratio, must be carefully checked to avoid overestimation of liver stiffness. Most of the results come from studies which have evaluated transient elastography, with less data available for the other technologies. Liver stiffness measurement could appear as a simple way to explore the liver, but several conditions must be met before deciding the patient management according to its result.

Ultrasound elastography

Physicians have used palpation as a diagnostic examination to understand the elastic properties of pathology for a long time since they realized that tissue stiffness is closely related to its biological characteristics. US elastography provided new diagnostic information about elasticity comparing with the morphological feathers of traditional US, and thus expanded the scope of the application in clinic. US elastography is now widely used in the field of diagnosis and differential diagnosis of abnormality, evaluating the degree of fibrosis and assessment of treatment response for a range of diseases. The World Federation of Ultrasound Medicine and Biology divided elastographic techniques into strain elastography (SE), transient elastography and acoustic radiation force impulse (ARFI). The ARFI techniques can be further classified into point shear wave elastography (SWE), 2D SWE, and 3D SWE techniques. The SE measures the strain, while the shear wave-based techniques (including TE and ARFI techniques) measure the speed of shear waves in tissues. In this review, we discuss the various techniques separately based on their basic principles, clinical applications in various organs, and advantages and limitations and which might be most appropriate given that the majority of doctors have access to only one kind of machine.

Diagnostic value of conventional ultrasound and shear wave elastography in detecting transjugular intrahepatic portosystemic shunt dysfunction

BACKGROUND

Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction can cause recurrent portal hypertension (PH)-related complications such as ascites and gastroesophageal variceal bleeding. Portography is invasive and costly limits its use as a screening modality.

PURPOSE

To assess the clinical value of conventional ultrasound in combination with point shear wave elastography (pSWE) to predict TIPS dysfunction.

MATERIAL AND METHODS

A total of 184 patients with cirrhosis scheduled for TIPS implantation were enrolled in this study and evaluated retrospectively. The splenoportal venous blood flow parameter, liver stiffness (LS), and spleen stiffness (SPS) were measured. Outcome measures included differences in portal vein velocity (PVV), splenic vein velocity (SPVV), LS, and SPS. The accuracy of change in PVV (ΔPVV), SPVV (ΔSPVV), and SPS (ΔSPS) to diagnose TIPS dysfunction was investigated.

RESULTS

TIPS dysfunction occurred in 28 of 184 patients (15.2%). Eighteen (64.3%) patients had shunt stenoses and 10 (35.7%) had shunt occlusion. Portal vein diameter (PVD), PVV, splenic vein diameter (SPVD), SPVV, LS, and SPS were not significantly different between the TIPS normal and TIPS dysfunction groups. Compared with the TIPS normal group, PVV and SPVV of the TIPS dysfunction group decreased significantly, whereas SPS increased significantly (P < 0.001). The values of areas under the receiver operating characteristic curves of ΔPVV, ΔSPVV, and ΔSPS for the diagnosis of TIPS dysfunction were 0.97, 0.96, and 0.87, respectively.

CONCLUSION

pSWE showed a diagnostic efficacy comparable to conventional ultrasound for diagnosing TIPS dysfunction and can be used routinely after TIPS procedures.

Artificial intelligence in the diagnosis of cirrhosis and portal hypertension

Clinically significant portal hypertension is associated with an increased risk of developing gastroesophageal varices and hepatic decompensation. Hepatic venous pressure gradient measurement and esophagogastroduodenoscopy are the gold-standard methods for assessing clinically significant portal hypertension and gastroesophageal varices, respectively. However, invasiveness, cost, and feasibility limit their widespread use, especially if repeated and serial evaluations are required to assess the efficacy of pharmacotherapy. Artificial intelligence describes a range of techniques that allow machines to perform tasks typically thought to require human reasoning and problem-solving skills. Artificial intelligence has made great strides in the field of medicine, and is also involved in portal hypertension diagnosis. Artificial intelligence tools will potentially transform our practice by leveraging massive amounts of data to personalize care to the right patient, in the right amount, at the right time. This review focuses on the recent advances in artificial intelligence for the noninvasive diagnosis of portal hypertension and gastroesophageal varices and monitoring of risk assessment of its complications in clinical practice.

Effect of Q-Box size on liver stiffness measurement by two-dimensional shear wave elastography

PURPOSE

To investigate the effect of the Q-Box size on liver stiffness (LS) measurement by two-dimensional shear wave elastography (2D SWE).

METHODS

Ninety-eight patients with chronic liver disease were enrolled. Each patient was continuously measured five times. The Q-Box diameter was adjusted to 10, 20, and 30 mm each time. The liver stiffness values (LSVs) at different diameters were compared in the following groups: LSVs ≤6.2 kPa, 6.2 kPa < LSVs ≤11 kPa, LSVs >11 kPa. The reliability and repeatability of LS measurement at different diameters were evaluated.

RESULTS

The differences in LSVs at different Q-Box diameters were statistically significant only when LSV ≤6.2 kPa (p = 0.004). There were no statistically significant differences in standard deviation (SD), SD/median, coefficient of variation (CV), and interquartile range (IQR)/median at different Q-Box diameters (p > 0.05). There were statistical differences in minimum LSVs and percentage of minimum LSVs ≤0.2 kPa as well as in stability index (SI) and percentage of SI <90% at different Q-Box diameters (p < 0.05). The intraclass correlation coefficients (ICCs) were up to 0.98 at Q-Box diameters of 10, 20, and 30 mm.

CONCLUSIONS

Our study showed that Q-Box size may lead to significant differences in LSVs, especially when LSVs ≤6.2 kPa. The Q-Box size had a large effect on the reliability of a single LS measurement but did not affect the repeatability of multiple measurements.

Portal hypertension is the main driver of liver stiffness in advanced liver cirrhosis

Liver stiffness (LS) is a novel non-invasive parameter widely used in clinical hepatology. LS correlates with liver fibrosis stage in non-cirrhotic patients. In cirrhotic patients it also shows good correlation with Hepatic Venous Pressure Gradient (HVPG). Our aim was to assess the contribution of liver fibrosis and portal hypertension to LS in patients with advanced liver cirrhosis. Eighty-one liver transplant candidates with liver cirrhosis of various aetiologies underwent direct HVPG and LS measurement by 2D shear-wave elastography (Aixplorer Multiwave, Supersonic Imagine, France). Liver collagen content was assessed in the explanted liver as collagen proportionate area (CPA) and hydroxyproline content (HP). The studied cohort included predominantly patients with Child-Pugh class B and C (63/81, 77.8%), minority of patients were Child-Pugh A (18/81, 22.2%). LS showed the best correlation with HVPG (r=0.719, p< 0.001), correlation of LS with CPA (r=0.441, p< 0.001) and HP/Amino Acids (r=0.414, p< 0.001) was weaker. Both variables expressing liver collagen content showed good correlation with each other (r=0.574, p<0.001). Multiple linear regression identified the strongest association between LS and HVPG (p < 0.0001) and weaker association of LS with CPA (p = 0.01883). Stepwise modelling showed minimal increase in r2 after addition of CPA to HVPG (0.5073 vs. 0.5513). The derived formula expressing LS value formation is: LS = 2.48 + (1.29 x HVPG) + (0.26 x CPA). We conclude that LS is determined predominantly by HVPG in patients with advanced liver cirrhosis whereas contribution of liver collagen content is relatively low.

Comparison of shear wave elastography (supersonic) with liver biopsy in a cohort of patients from a medium-income country: an observational study

INTRODUCTION

shear-wave elastography is a non-invasive diagnostic test that calculates the degree of liver fibrosis by measuring liver elasticity. This technique was recently introduced in Colombia. Thus, cutoff points delineating the change between fibrosis stages (using the Metavir scale) have not been previously defined in our patient population.

PATIENTS AND METHODS

a retrospective study was performed of patients who had undergone two-dimensional shear-wave elastography (2D-SWE) and liver biopsy (LB) between June 2010 and June 2018 at a private outpatient hepatology center in Bogota, Colombia. We used a training dataset (subjects with time between biopsy and 2D-SWE of ≤ 6 months) to establish diagnostic cutoff values and a test dataset (subjects with time between biopsy and 2D-SWE of > 6 months) to validate our results.

RESULTS

a total of 453 subjects (training dataset, n = 153; test dataset, n = 300) were included. In the training dataset, the cutoff points were 7.6, 8.4, 9.5 and 10.9 kPa, and the areas under the curve were 0.75, 0.83, 0.89 and 0.94 for mild fibrosis, significant fibrosis, advanced fibrosis and cirrhosis, respectively. In the test dataset, the areas under the curve were 0.77, 0.78, 0.83 and 0.89 for mild fibrosis, significant fibrosis, advanced fibrosis, and cirrhosis, respectively.

CONCLUSION

two-dimensional shear-wave elastography was reliable and useful for the non-invasive evaluation of liver fibrosis, particularly in patients with advanced fibrosis and cirrhosis. Cutoff points for fibrosis in a Hispanic population were described.

Ultrasound-Based Quantification of Fibrosis and Steatosis with a New Software Considering Transient Elastography as Reference in Patients with Chronic Liver Diseases

The goal of this study was to evaluate the performance of two new ultrasound-based techniques (ShearWave PLUS elastography [2-D-SWE PLUS], SSp PLUS Imaging [SSp PLUS]) implemented on the Aixplorer Mach 30 ultrasound system (Supersonic Imagine, Aix-en-Provence, France) for the non-invasive assessment of liver steatosis and fibrosis, using transient elastography (TE) with the controlled attenuation parameter (CAP) as reference. This monocentric cross-sectional study included 133 consecutive adult patients with chronic hepatopathies. Liver stiffness and steatosis were evaluated in the same session using the techniques mentioned above. An excellent correlation was observed between liver stiffness measurements obtained with 2-D-SWE PLUS and TE (r = 0.92, p < 0.0001). The best cutoff value of 2-D-SWE PLUS for predicting F≥2 was 6.8 kPa; for F≥3, 8.4 kPa; and for F4, 11 kPa. With respect to steatosis evaluation, a strong negative correlation between CAP and SSp PLUS values (r = -0.70, p < 0.0001) was obtained. The best SSp PLUS cutoff value for predicting steatosis was 1537 m/s.

Noninvasive Assessment of Hepatitis C Virus Infected Patients Using Vibration-Controlled Transient Elastography

Chronic infection with hepatitis C virus (HCV) is one of the leading causes of cirrhosis and hepatocellular carcinoma (HCC). Surveillance of these patients is an essential strategy in the prevention chain, including in the pre/post-antiviral treatment states. Ultrasound elastography techniques are emerging as key methods in the assessment of liver diseases, with a number of advantages such as their rapid, noninvasive, and cost-effective characters. The present paper critically reviews the performance of vibration-controlled transient elastography (VCTE) in the assessment of HCV patients. VCTE measures liver stiffness (LS) and the ultrasonic attenuation through the embedded controlled attenuation parameter (CAP), providing the clinician with a tool for assessing fibrosis, cirrhosis, and steatosis in a noninvasive manner. Moreover, standardized LS values enable proper staging of the underlying fibrosis, leading to an accurate identification of a subset of HCV patients that present a high risk for complications. In addition, VCTE is a valuable technique in evaluating liver fibrosis prior to HCV therapy. However, its applicability in monitoring fibrosis regression after HCV eradication is currently limited and further studies should focus on extending the boundaries of VCTE in this context. From a different perspective, VCTE may be effective in identifying clinically significant portal hypertension (CSPH). An emerging prospect of clinical significance that warrants further study is the identification of esophageal varices. Our opinion is that the advantages of VCTE currently outweigh those of other surveillance methods.

Assessment of liver fibrosis with liver and spleen stiffness measured by sound touch elastography, serum fibrosis markers in patients with chronic hepatitis B

OBJECTIVES

To evaluate the performance of liver stiffness (LS) and spleen stiffness (SS) by using the sound touch elastography (STE) technique and compare with those of the splenic index, aspartate transaminase-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) index, King's score and combined models for diagnosing and staging fibrosis in chronic hepatitis B (CHB).

METHODS

One hundred patients with CHB underwent STE and serological tests. LS and SS values were measured with STE technique, and splenic index was calculated. Staging of fibrosis was determined with liver biopsy. Correlations between the individual parameters and the stage of fibrosis were evaluated with the Spearman correlation analysis. The area under the receiver operating characteristic curve (AUROC) was calculated to analyze the performance of all methods.

RESULTS

Among all individual parameters, LS showed the highest AUROC for diagnosing fibrosis of ≥S2, ≥S3, and S4 stages (AUROC: 0.70, 0.86, and 0.96, respectively; all P < 0.05). The AUROC of combined model 1 (LS and SS) and 2 (LS, SS, APRI, FIB-4 index, King's score) for diagnosing ≥S2, ≥S3, and S4 fibrosis were 0.70, 0.86, 0.97, and 0.70, 0.86, 0.96, respectively, which were higher than those of APRI, FIB-4 index and the King's score (P < 0.05). No significant differences were found between two combined models and LS for staging fibrosis (P > 0.05).

CONCLUSIONS

LS measurement is reliable for diagnosing and staging fibrosis in CHB, with a better performance than SS, splenic index and serum biomarkers. It is also comparable with the performance of combined models.

Comparison of point and two-dimensional shear wave elastography of the spleen in healthy subjects

BACKGROUND

Few systematic comparative studies of the different methods of physical elastography of the spleen are currently available.

AIM

To compare point shear wave and two-dimensional elastography of the spleen considering the anatomical location (upper, hilar, and lower pole).

METHODS

As part of a prospective clinical study, healthy volunteers were examined for splenic elasticity using four different ultrasound devices between May 2015 and April 2017. The devices used for point shear wave elastography were from Siemens (S 3000) and Philips (Epiq 7), and those used for two-dimensional shear wave elastography were from GE (Logiq E9) and Toshiba (Aplio 500). In addition, two different software versions (5.0 and 6.0) were evaluated for the Toshiba ultrasound device (Aplio 500). The study consisted of three arms: A, B, and C.

RESULTS

In study arm A, 200 subjects were evaluated (78 males and 122 females, mean age 27.9 ± 8.1 years). In study arm B, 113 subjects were evaluated (38 men and 75 women, mean age 26.0 ± 6.3 years). In study arm C, 44 subjects were enrolled. A significant correlation of the shear wave velocities at the upper third of the spleen (r = 0.33088, P < 0.0001) was demonstrated only for the Philips Epiq 7 device compared to the Siemens Acuson S 3000. In comparisons of the other ultrasound devices (GE, Siemens, Toshiba), no comparable results could be obtained for any anatomical position of the spleen. The influencing factors age, gender, and body mass index did not show a clear correlation with the measured shear wave velocities.

CONCLUSION

The absolute values of the shear wave elastography measurements of the spleen and the two different elastography methods are not comparable between different manufacturers or models.

Noninvasive Detection of Clinically Significant Portal Hypertension in Compensated Advanced Chronic Liver Disease

Patients with compensated advanced chronic liver disease have different prognoses depending on the presence of portal hypertension. Current non-invasive diagnostic methods allow identification of clinically significant portal hypertension. Portosystemic collaterals on imaging or liver stiffness of more than 20 to 25 kPa by using transient elastography identifies patients with clinically significant portal hypertension. Patients with liver stiffness of less than 20 kPa and platelet count of greater than 150 g/L can avoid endoscopy. This rule could be expanded using spleen stiffness. Methods to risk stratify for portal hypertension in compensated advanced chronic liver disease and successfully treated chronic hepatitis C and B are subject of research.

Assessing Baveno VI Criteria Using Liver Stiffness Measured with a 2D-Shear Wave Elastography Technique

The present study evaluates the performance of Baveno VI criteria, using liver stiffness (LS) assessed with a 2D-SWE elastography technique, for predicting high-risk varices (HRV) in patients with compensated advanced chronic liver disease (cACLD). A secondary aim was to determine whether the use of spleen stiffness measurements (SSMs), as additional criteria, increases the performance of the 2D-SWE Baveno VI criteria. Data were collected from 208 subjects with cACLD, who underwent abdominal ultrasound, liver and spleen stiffness measurements, and upper digestive endoscopy. HRV were defined as grade 1 esophageal varices (EV) with red wale marks, grade 2/3 EV, and gastric varices. A total of 35.6% (74/208) of the included subjects had HRV. The optimal LS cut-off value for predicting HRV was 12 kPa (AUROC-0.80). Using both LS cut-off value < 12 kPa and a platelet cut-off value > 150 × 109 cells/L as criteria to exclude HRV, 52/208 (25%) subjects were selected, 88.5% (46/52) were without EV, 9.6% (5/52) had grade 1 EV, and 1.9% (1/52) had HRV. Thus 98% of the subjects were correctly classified as having or not having HRV and 25% of the surveillance endoscopies could have been avoided. Using SS < 13.2 kPa and a platelet cut-off value > 150 × 109 cells/L as additional criteria for the patients that were outside the initial ones, 32.7% of the surveillance endoscopies could have been avoided.

The Combination of Shear Wave Elastography and Platelet Counts Can Effectively Predict High-Risk Varices in Patients with Hepatitis B-Related Cirrhosis

Background

Baveno VI criteria, based on liver stiffness (LS) measured by transient elastography and platelet counts (PLT), have been proposed to avoid unnecessary endoscopy screening for high-risk varices (HRVs). However, the cut-off value of LS measured by 2D-SWE and PLT to predict HRVs in compensated hepatitis B-related cirrhotic patients remains unknown.

Aims

To prospectively analyze the cut-off of the combination of LS measured by 2D-SWE and PLT in predicting HRVs and the influence of antiviral therapies in its efficacy.

Methods

Serum parameters, LS, and endoscopy results were obtained from 160 compensated hepatitis B-related cirrhotic patients. The accuracy of the combined algorithm was assessed in the whole cohort and subgroups with or without consecutive antiviral therapies in the past 6 months.

Results

In the whole cohort, the optimal cut-off value of LS for HRVs was 14.5 kPa. Patients with a LS value < 14.5 kPa with a PLT value > 110 × 10⁹/L can be excluded from HRVs (NPV = 0.99, endoscopy saved rates = 0.68). Conversely, a LS value of ≥14.5 kPa and a PLT value of ≤110 × 10⁹/L indicated HRVs, with accurate rates of 82.35%, and 10.63% of patients can avoid additional endoscopy screening. Moreover, antiviral therapy had no significant effect on the accuracy and rates saved from further endoscopy screening, when comparing patients with or without antiviral therapies (all p values > 0.05).

Conclusions

The combination of LS (14.5 kPa) measured by 2D-SWE and PLT (110 × 10⁹/L) can predict HRVs accurately in compensated hepatitis B-related cirrhotic patients without significant interference of antiviral therapy histories.

Approaches to the Diagnosis of Portal Hypertension: Non-Invasive or Invasive Tests?

Portal hypertension is the main driver of complications in patients with advanced chronic liver disease (ACLD) and is defined by values of hepatic venous pressure gradient measurement (HVPG) >5 mmHg. Values of HVPG ≥10 mmHg determine the presence of clinically significant portal hypertension (CSPH), the main predictor of the risk of variceal bleeding, hepatic decompensation, and mortality. However, its measurement is invasive and requires high expertise, so its routine use outside third level centers or clinical trials is limited. In the last decades, several non-invasive tests (NITs) have been developed and validated for the diagnosis of portal hypertension. Among these, liver (LSM) and spleen stiffness measurement (SSM) are the most promising tools available, as they have been proven accurate to predict CSPH, high-risk esophageal varices, decompensation, and mortality in patients with ACLD. In the last Baveno VI Consensus proceedings, LSM evaluation was recommended for the first time for diagnosis of CSPH (LSM >20-25 kPa) and the screening of patients with a low probability of having high-risk varices (LSM <20 kPa and platelet count >150.000/mm³). In this review, we aimed to summarize the growing evidence supporting the use of non-invasive tests for the evaluation of portal hypertension in patients with chronic liver disease.

Spleen Stiffness for Predicting Varices Needing Treatment: Comparison between Two Different Elastography Techniques (Point vs. 2D-SWE)

The study aimed to establish the benefits of using spleen stiffness values measured by two elastography techniques as noninvasive markers for predicting varices needing treatment and comparing their performances. A prospective study was performed, including 107 subjects with compensated liver cirrhosis, who underwent upper digestive endoscopy, as well as spleen stiffness measurements by means of two elastography techniques: pSWE (point shear wave elastography using Virtual Touch Quantification-Siemens Acuson S2000) and 2D-SWE (2D-shear wave elastography-LOGIQ E9, General Electric). Reliable spleen stiffness measurements were obtained in 96.2% (103/107) patients by means of 2D-SWE and in 94.4% (101/107) subjects with pSWE; therefore, 98 subjects were included in the final analysis, of which 40.8% (40/98) had varices needing treatment. The optimal spleen stiffness cut-off value by 2D-SWE for predicting varices needing treatment was 13.2 kPa (AUROC 0.84), while for pSWE, it was 2.91 m/s (AUROC 0.90). Based on AUROC comparison, no difference between the performance of the two techniques for predicting varices needing treatment was found (p=0.1606). In conclusion, spleen stiffness measured by either 2D-SWE or pSWE is a reliable surrogate marker, with good feasibility, applicability, and predictive accuracy for varices needing treatment, with no significant difference between techniques.

Measurement of liver and spleen stiffness as complementary methods for assessment of liver fibrosis in autoimmune hepatitis

BACKGROUND AND AIMS

Liver stiffness measurements (LSM), commonly performed by transient elastography (TE) or two-dimensional shear wave elastography (2D-SWE), are used to quantify liver fibrosis. Active hepatitis, a hallmark of autoimmune hepatitis (AIH), could bias LSM. This bias might be overcome by measurement spleen 2D-SWE. Here, we compare liver and spleen 2D-SWE to TE and liver biopsy (LB) in prospectively recruited patients with AIH.

METHODS

We analysed liver and spleen 2D-SWE in relation to liver TE in 90 patients treated ≥ 6 months for AIH. Liver and spleen 2D-SWE were also compared to LB in 63 individuals with AIH. Finally, we evaluated these tools in 220 patients with AIH and during 18 months follow-up.

RESULTS

Liver 2D-SWE correlated with surrogate markers of active hepatitis (ALT and IgG, both P < .001) but there was no link between spleen 2D-SWE and ALT. Liver 2D-SWE, but not spleen 2D-SWE, was associated with histopathological inflammatory score (P < .01). When compared to LB, the optimal cut-offs for detecting cirrhosis by liver and spleen 2D-SWE were 16.1 kPa (AUROC 0.93) and 29.8 kPa (AUROC 0.95), respectively. In patients with active hepatitis the combined diagnostic approach including liver and spleen 2D-SWE had significantly better AUROC for detecting cirrhosis than liver 2D-SWE alone.

CONCLUSIONS

Liver and spleen 2D-SWE are reliable complementary methods for the diagnosis of advanced fibrosis in AIH. Spleen 2D-SWE seems to be less biased by inflammation and could facilitate fibrosis assessment in therapy-naïve patients or in the presence of active hepatitis.

Liver stiffness measured by two-dimensional shear-wave elastography predicts hepatic vein pressure gradient at high values in liver transplant candidates with advanced liver cirrhosis

Liver stiffness is a reliable non-invasive predictor of Hepatic Venous Pressure Gradient (HVPG) above 10 mm Hg. However, it failed to predict higher thresholds of HVPG. Our aim was to investigate whether liver stiffness and selected previously published non-invasive blood biomarkers could predict higher HVPG thresholds in liver transplant candidates without ongoing alcohol use. One hundred and nine liver transplant candidates with liver cirrhosis of various aetiologies underwent direct HVPG measurement, liver stiffness measurement by 2D shear-wave elastography (Aixplorer Multiwave, Supersonic Imagine, France) and assessment of blood HVPG biomarkers (osteopontin, VCAM-1, IL-6, TNF-α, IL-1ra/IL-1F3 and ELF score). The correlation between liver stiffness and HVPG was linear up to 30 mm Hg of HVPG (r = 0.765, p < 0.0001). The regression lines had similar slopes for HVPG values below and above 16 mm Hg (p > 0.05) and the correlation in patients with HVPG <16 mm Hg (r = 0.456, p = 0.01) was similar to patients with HVPG ≥ 16 mm Hg (r = 0.499, p < 0.0001). The correlation was similar in the subgroup patients with alcoholic (r = 0.718, p < 0.0001), NASH (r = 0.740, p = 0.008), cryptogenic (r = 0.648, p = 0,0377), cholestatic and autoimmune (r = 0.706, p < 0.0001) and viral cirrhosis (r = 0.756, p < 0.0001). Liver stiffness distinguished patients with HVPG above 16, and 20 mm Hg with AUROCs 0.90243, and 0.86824, sensitivity 0.7656, and 0.7027, and specificity 0.9333, and 0.8750. All studied blood biomarkers correlated better with liver stiffness than with HVPG and their AUROCs did not exceed 0.8 at both HVPG thresholds. Therefore, a composite predictor superior to liver stiffness could not be established. We conclude that liver stiffness is a clinically reliable predictor of higher HVPG thresholds in non-drinking subjects with advanced liver cirrhosis.

Performance and cutoffs for liver fibrosis staging of a two-dimensional shear wave elastography technique

OBJECTIVES

To assess performance and cutoffs of the 2-dimensional shear wave elastography technique available on the Aplio i800 ultrasound system (Canon Medical Systems, Japan), using transient elastography as reference standard, and to assess the correlation of shear-wave-speed dispersion with liver fibrosis or steatosis.

METHODS

This was a single-center cross-sectional study. The correlations between values obtained with transient elastography and 2-dimensional-shear wave elastography, and between shear-wave-speed dispersion and fibrosis or steatosis, were assessed with Pearson's r. The diagnostic performance of the 2-dimensional-shear wave elastography for staging significant fibrosis and severe fibrosis compared to transient elastography was assessed using the area under the receiver operating characteristic curve analysis.

RESULTS

Three hundred sixty-seven patients (198 males and 169 females) were studied. There was a high correlation between 2-dimensional-shear wave elastography and transient elastography (r = 0.87, P < 0.0001). The area under the receiver operating characteristics of 2-dimensional-shear wave elastography for staging significant fibrosis (F2) and severe fibrosis (F3-F4), respectively, were 0.97 (95% confidence interval, 0.91-0.98) and 0.97 (95% confidence interval, 0.95-0.99). The best cutoffs for significant fibrosis and severe fibrosis, respectively, were > 7 and > 9 kPa. Shear-wave-speed dispersion showed a high correlation with fibrosis (r = 0.85, P < 0.0001), whereas there was a very weak correlation with steatosis.

CONCLUSIONS

The results of this study show that this 2-dimensional-shear wave elastography technique is accurate for staging liver fibrosis. Shear-wave-speed dispersion is highly correlated with liver fibrosis but not with steatosis.