Algorithm to rule out clinically significant portal hypertension combining Shear-wave elastography of liver and spleen: a prospective multicentre study

Evaluation of Noninvasive Tools for Predicting Esophageal Varices in Patients With Cirrhosis at Tygerberg Hospital, Cape Town

Background: In patients with cirrhosis, esophageal variceal hemorrhage (EVH) is a devastating consequence of portal hypertension (PH). Upper endoscopy is considered the gold standard for the detection and diagnosis of esophageal varices (EVs), despite being invasive and costly. This study was aimed at identifying and evaluating the diagnostic accuracy of noninvasive tools in predicting EVs in patients with compensated cirrhosis. Methods: This cross-sectional study included 50 patients with compensated cirrhosis at the Tygerberg Hospital Gastroenterology Clinic in Cape Town between November 2022 and May 2023. We collected clinical, anthropometric, and laboratory data from patients' physical and electronic charts. All patients underwent an abdominal ultrasound, vibration-controlled transient elastography (VCTE) to assess liver and splenic stiffness, and upper endoscopy. In this comparative study, we evaluated the diagnostic accuracy of different noninvasive tools in detecting EVs in patients with compensated cirrhosis. Results: Of the 50 patients included in the study, 30 (60%) were female and 20 (40%) were male. The patients' age ranged from 18 to 83, with a mean age of 46.6 years. Cirrhosis was mainly due to alcohol use (n = 11, 22%), hepatitis B virus (HBV) infection (n = 11, 22%), and autoimmune hepatitis (n = 10, 20%). The patients included in the study were divided into two subgroups: with (n = 34, 68%) or without (n = 16, 32%) EVs. Statistically significant differences were detected between groups in platelet count (PC), liver stiffness measurement (LSM), spleen stiffness measurement (SSM), portal vein diameter (PVD), bipolar spleen diameter (SBD), aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis-4 index (FIB-4), platelet/bipolar spleen diameter ratio (PSR), liver stiffness-spleen size-platelet ratio (LSPS), liver stiffness-spleen stiffness-platelet ratio score (LS3PS), and spleen stiffness-spleen size-platelet ratio score (SSPS) (p < 0.001). The highest diagnostic precision was observed with SSM (96%), SSPS (96%), LS3PS (94%), LSPS (94%), PSR (94%), and PC (92%). SBD (88%), LSM (86%), APRI (82%), and FIB-4 (82%) had the lowest diagnostic accuracy. Conclusion: SSM and SSPS have the highest diagnostic accuracy for predicting the presence of EVs in patients with compensated cirrhosis. LSPS, LS3PS, and PSR come second at 94%. We recommend SSM and SSPS in institutions with transient elastography equipped with the software necessary to measure splenic stiffness. We introduce and propose LS3PS as a novel composite score for predicting the presence of EVs in patients with compensated cirrhosis. Large-sample-size studies are needed to validate these prediction scores and to allow direct comparison with Baveno VII. These prediction tools can help clinicians avoid unnecessary endoscopic procedures in patients with compensated cirrhosis, especially in developing countries with limited resources such as South Africa.

THE ROLE OF ELASTOGRAPHY IN CLINICALLY SIGNIFICANT PORTAL HYPERTENSION

• In compensated cirrhosis, using non-invasive methods would exempt the patient from the need of an endoscopy. • The Baveno VII presented the "rule of 5" for Vibration-Controlled Transient Elastography; liver stiffness measurement ≤15 kPa and platelets >150.000/mm3 exclude clinically significant portal hypertension (CSPH), while when ≥25 kPa is highly suggestive of CSPH. • Spleen stiffness measurement has been proposed as a more specific technique to predict the presence of CSPH. • Elastography has gained prestige in the non-invasive evaluation of patients with advanced chronic liver disease by allowing prophylactic measures to be taken when suggesting the presence of CSPH. This is a narrative review that aims to discuss the importance of elastographic methods in the evaluation of clinically significant portal hypertension (CSPH) in cirrhotic patients, where the authors propose an algorithm for evaluating these patients. In compensated advanced chronic liver disease, the goal is to prevent the development of CSPH and, in those already with CSPH, prevent the appearance of gastroesophageal varices (GEV) and other complications of portal hypertension. In compensated cirrhosis, the prevalence of GEV is 30-40%, of which 10-20% are at risk of bleeding. Therefore, using non-invasive methods would exempt the patient from the need of an endoscopy. Hepatic Elastography is a non-invasive, safe, reproducible method, available through many techniques: Vibration-Controlled Transient Elastography (VCTE), Shear Wave Elastography (SWE) and Magnetic Resonance Elastography (MRE). The Baveno VII presented the "rule of 5" for VCTE: liver stiffness measurement (LSM) ≤15 kPa and platelets >150.000/mm3 exclude CSPH, while an LSM ≥25 kPa is highly suggestive of CSPH. Also, the "rule of 4" for SWE has been proposed: patients with ≥17 kPa could be considered as having CSPH. At last, spleen stiffness measurement (SSM) has been proposed as a more specific technique to predict the presence of CSPH. In conclusion, elastography has gained prestige in the non-invasive evaluation of patients with advanced chronic liver disease by allowing prophylactic measures to be taken when suggesting the presence of CSPH.

CT Rule-in and Rule-out Criteria for Clinically Significant Portal Hypertension in Chronic Liver Disease

Background The value of CT in assessment of clinically significant portal hypertension (CSPH) has not been well determined. Purpose To evaluate the performance of CT features that have been associated with portal hypertension for diagnosing CSPH in patients with chronic liver disease (CLD). Materials and Methods This retrospective study included patients with CLD who underwent contrast-enhanced CT and subsequent hepatic venous pressure gradient (HVPG) measurement within 3 months at two tertiary institutions from January 2001 to December 2019. Two readers independently evaluated the presence of gastroesophageal varix, spontaneous portosystemic shunt (SPSS), and ascites on CT images. Splenomegaly at CT was determined using three methods, as follows: personalized or fixed volume criteria, based on spleen volume as measured by a deep learning algorithm, or manually measured spleen diameter. The diagnostic performance of these findings alone or in combination for detecting CSPH (HVPG ≥10 mm Hg) was evaluated. Results A total of 235 patients (mean age, 53.2 years ± 13.0 [SD]; 155 male patients), including 110 (46.8%) with CSPH, were included. Detection of CSPH according to the presence of both splenomegaly and at least one other CT feature (ie, gastroesophageal varix, SPSS, and ascites) achieved specificities of 94.4%-97.6%, whereas detection of CSPH according to the presence of any feature (ie, splenomegaly, gastroesophageal varix, SPSS, or ascites) achieved sensitivities of 94.5%-98.2%. When employing the former as rule-in criteria with the absence of splenomegaly, gastroesophageal varix, SPSS, and ascites as rule-out criteria for CSPH, 171-185 (range, 72.8%-78.7%) of 235 patients were correctly classified as either having CSPH or not, seven to 13 (range, 3%-5.5%) of 235 patients were incorrectly classified, and 42-54 (range, 17.9%-23%) of 235 patients were unclassified. Conclusion The presence or absence of splenomegaly, gastroesophageal varix, SPSS, and/or ascites on CT images may be useful for ruling in and ruling out CSPH in patients with CLD. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Fraum in this issue.

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.

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.

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.

Assessment of chronic liver disease by multiparametric ultrasound: results from a private practice outpatient facility

PURPOSE

To assess chronic liver disease (CLD) using multiparametric US in a private practice setting in a cohort of patients with increased skin-to-liver distance.

METHODS

110 consecutive patients with increased skin-to-liver distance scheduled for US assessment of CLD were reviewed for study completion time, liver stiffness values (LS), attenuation imaging, and shear wave dispersion slope. The ROI was placed 2 cm below the liver capsule. The study included patients with NAFLD/NASH (68), hepatitis C (30), prior Fontan surgery (1), elevated liver function tests (5), alcohol abuse (3), hepatitis B (2), and primary biliary cirrhosis (1). IQR/M values were obtained. Comparison of less experienced sonographers (LES) and more experienced sonographers (MES) were evaluated through Student's t test for independent data. Pearson coefficient r of correlation among quantitative variables was calculated.

RESULTS

The mean time to perform the exam was 129.7 ± 62.1 s. There was a statistically significant difference between LES and MES. The mean IQR/M for LS was 12.3 ± 5.5% m/s. Overall, in a cohort of difficult patients, 4.5% of LS values were not reliable. Fat quantification using attenuation imaging had a mean value of 0.60 ± 0.15 dB/cm/MHz (range 0.35-0.98 cm/dB/MHz) with an IQR/M of 14.7 ± 9.2%. Less reliable measurements of steatosis were obtained in 4.5% of patients. The mean shear wave dispersion slope was 12.74 ± 4.05 (m/s)/kHz (range 7.7-27.5 (m/s)/kHz) with an IQR/M of 38.7 ± 20.2% (range 3-131%). 20.9% of patients had values suggestive of compensated advanced chronic liver disease (cACLD).

CONCLUSION

Multiparametric US can provide assessment of CLD in less than 3 min in most patients and identify patients at risk for cACLD.

EASL Clinical Practice Guidelines on non-invasive tests for evaluation of liver disease severity and prognosis - 2021 update

Non-invasive tests are increasingly being used to improve the diagnosis and prognostication of chronic liver diseases across aetiologies. Herein, we provide the latest update to the EASL Clinical Practice Guidelines on the use of non-invasive tests for the evaluation of liver disease severity and prognosis, focusing on the topics for which relevant evidence has been published in the last 5 years.

Portal hypertension in cirrhosis: Pathophysiological mechanisms and therapy

Portal hypertension, defined as increased pressure in the portal vein, develops as a consequence of increased intrahepatic vascular resistance due to the dysregulation of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cells (HSCs), frequently arising from chronic liver diseases. Extrahepatic haemodynamic changes contribute to the aggravation of portal hypertension. The pathogenic complexity of portal hypertension and the unsuccessful translation of preclinical studies have impeded the development of effective therapeutics for patients with cirrhosis, while counteracting hepatic and extrahepatic mechanisms also pose a major obstacle to effective treatment. In this review article, we will discuss the following topics: i) cellular and molecular mechanisms of portal hypertension, focusing on dysregulation of LSECs, HSCs and hepatic microvascular thrombosis, as well as changes in the extrahepatic vasculature, since these are the major contributors to portal hypertension; ii) translational/clinical advances in our knowledge of portal hypertension; and iii) future directions.

Liver Stiffness Is a Predictor of Rebleeding in Patients With Hepatitis B-Related Cirrhosis: A Real-World Cohort Study

Background: Esophageal vein rebleeding is a life-threatening complication of liver cirrhosis. However, the role of non-invasive methods that were developed to evaluate the severity of chronic liver disease, especially in rebleeding, remains unclear. Aims: To evaluate the performance of liver stiffness and non-invasive fibrosis scores in predicting esophageal vein rebleeding in hepatitis B virus (HBV) cirrhotic patients. Methods: A prospective analysis of 194 HBV patients between 2017 and 2021 was performed. Receiver operating characteristic (ROC) curves and time-dependent ROC curves were used to assess the power for predicting rebleeding with non-invasive fibrosis score and liver stiffness. Results: During the median follow-up time of 68.28 weeks, 55 patients experienced rebleeding. In the entire cohort, the area under the ROC curve for liver stiffness measurement (LSM) predicting for rebleeding was 0.837, with a cut-off value of 17.79 kPa, and the time-dependent ROC curve also showed stable prediction performance of LSM. The predictive ability of the non-invasive fibrosis score was less than that of LSM, and there were statistical differences. Moreover, patients using non-selective beta-blockers and HBV DNA-negative patients experienced significantly reduced rebleeding. Conclusions: Compared with non-invasive fibrosis scores, LSM can more simply and accurately predict rebleeding events of hepatitis B liver cirrhosis.

New model predicting gastroesophageal varices and variceal hemorrhage in patients with chronic liver disease

INTRODUCTION AND OBJECTIVES

The predictors for gastroesophageal varices (GOV) and hemorrhage development have not been well studied in different liver diseases or different population. This study aimed to evaluate whether a new algorithm focusing on chronic hepatitis B (CHB) patients is also applicable to other chronic liver diseases (CLDs) in Chinese population.

PATIENTS OR MATERIALS AND METHODS

We retrospectively analyzed 659 CHB patients and 386 patients with other CLDs. A total of 439 CHB patients were included in training set, the other 220 CHB patients and other patients with CLDs were included in validation set. A new algorithm for diagnosing GOV was established and its sensitivity and specificity for predicting the varices was verified.

RESULTS

Multivariable logistic regression revealed that the rough surface of the liver (p<0.001), splenic thickness (p<0.001), and liver stiffness (p=0.006) were independent predictors of GOV. The new algorithm was considered to be a reliable diagnostic model to evaluate the presence of varices. The AUROC was 0.94 (p<0.001) in CHB validation set and 0.90 (<0.001) in non-CHB validation set. When the cut-off value was chosen as -1.048, the sensitivity and specificity in diagnosing GOV in CHB population were 89.1% and 82.5%, respectively. Importantly, the new algorithm accurately predicted the variceal hemorrhage not only in CHB patients, but also in patients with other CLDs.

CONCLUSION

The new algorithm is regarded as a reliable model to prognosticate varices and variceal hemorrhage, and stratified not only the high-risk CHB patients, but also in patients with other CLDs for developing GOV and variceal bleeding.

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.

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.

CT-based liver surface nodularity for the detection of clinically significant portal hypertension: defining measurement quality criteria

PURPOSE

To establish measurement quality criteria for the noninvasive assessment of clinically significant portal hypertension (CSPH) in patients with cirrhosis using CT-based liver surface nodularity (LSN) measurements.

METHODS

Seventy-four consecutive patients with cirrhosis (mean 62 ± 13 years), including 30 with CSPH (41%), underwent CT and hepatic venous pressure gradient measurements. Three independent readers performed 15 LSN measurements/patient using dedicated software. LSN was computed based on the median and means of one to 15 measurements. Accuracy for diagnosing CSPH was assessed using receiver operating characteristic (ROC) curve analysis. Variability was assessed by the intra-class correlation coefficient (ICC) and the Bland-Altman plot (BA). Quality criteria were identified to maximize the accuracy of LSN and minimize variability.

RESULTS

The area under the (AU) ROCs of mean and median LSN measurements based on one to 15 measurements ranged from 0.79 ± 0.05 to 0.91 ± 0.04 and 0.86 ± 0.04 to 0.91 ± 0.03, respectively, with no difference on pair-wise comparisons (all p > 0.05). AUROCs of LSN increased from one to eight and leveled off between eight and 15 measurements. Inter- and intra-reader variability decreased from one to 15 measurements, with only slight improvement after more than eight measurements. Intra- and inter-observer agreements were excellent with eight measurements (ICC = 0.90 [95%CI 0.84-0.94], and ICC = 0.93 [95%CI 0.89-0.95], respectively), and variability for intra-observer and inter-observer agreement was low (BA bias 4.2% (95% limits of agreement [LoA] [- 15.3; + 23.7%]) and 4.8% LoA [ - 17.5; + 27.1%], respectively).

CONCLUSIONS

CT-based LSN measurement is highly reproducible and accurate. We suggest using at least 8 valid measurements to determine the mean LSN value for the detection of CSPH.

Update to the Society of Radiologists in Ultrasound Liver Elastography Consensus Statement

This multidisciplinary update of the Society of Radiologists in Ultrasound consensus statement on liver elastography incorporates the large volume of new information available in the literature since the initial publication. The recommended procedure for acquiring stiffness measurements is reviewed. There has been substantial improvement in the acoustic radiation force impulse (ARFI) technology-most notably the addition of a quality assessment of the shear wave propagation. Due to the efforts of the Quantitative Imaging Biomarkers Alliance, or QIBA, the variability of liver stiffness measurements between systems had decreased. There are now effective treatments for hepatitis B and hepatitis C, and follow-up after effective treatment should be based on the use of the delta change of the value obtained at viral eradication or suppression. Because the detection of compensated advanced chronic liver disease (cACLD) is very important, the new guidelines are made based on the probability of cACLD for given stiffness values. The panel recommends a vendor-neutral rule of four for interpretation for ARFI techniques. This new method simplifies interpretation of liver stiffness results and is more clinically relevant.

2D shear wave liver elastography by Aixplorer to detect portal hypertension in cirrhosis: An individual patient data meta-analysis

BACKGROUND & AIMS

Liver stiffness measured with 2-dimensional shear wave elastography by Supersonic Imagine (2DSWE-SSI) is well-established for fibrosis diagnostics, but non-conclusive for portal hypertension.

METHODS

We performed an individual patient data meta-analysis of 2DSWE-SSI to identify clinically significant portal hypertension (CSPH), severe portal hypertension and large varices in cirrhosis patients, using hepatic venous pressure gradient and upper endoscopy as reference. We used meta-analytical integration of diagnostic accuracies with optimized rule-out (sensitivity-90%) and rule-in (specificity-90%) cut-offs.

RESULTS

Five studies from seven centres shared data on 519 patients. After exclusion, we included 328 patients. Eighty-nine (27%) were compensated and 286 (87%) had CSPH. 2DSWE-SSI < 14 kPa ruled out CSPH with a summary AUROC (sROC), sensitivity and specificity of 0.88, 91% and 37%, and correctly classified 85% of patients, with minimal between-study heterogeneity. The false negative rate was 60%, of which decompensated patients accounted for 78%. 2DSWE-SSI ≥ 32 kPa ruled in CSPH with sROC, sensitivity, specificity and correct classifications of 0.83, 47%, 89% and 55%. In a subgroup analysis, the 14 kPa cut-off showed consistent sensitivity and higher specificity for patients with compensated cirrhosis, without ascites, viral aetiology or BMI < 25 kg/m² . 2DSWE-SSI ruled out severe portal hypertension and large varices with fewer correctly classified and lower sROC, and with minimal benefit for ruling in.

CONCLUSION

Liver stiffness using 2-dimensional shear wave elastography below 14 kPa may be used to rule out clinically significant portal hypertension in cirrhosis patients, but this would need validation in populations of compensated liver disease. 2DSWE-SSI cannot predict varices needing treatment.

Spleen Stiffness Differentiates Between Acute and Chronic Liver Damage and Predicts Hepatic Decompensation

OBJECTIVES

Spleen stiffness (SS) correlates with liver stiffness (LS) and hepatic venous pressure gradient. The latter is currently the most accurate predictor of hepatic decompensation. Our study aims to check whether SS has a similar predictive capability, while being an easy-to-perform noninvasive test in a real-life patient cohort.

METHODS

Concomitantly, 210 successive patients were examined and received liver and SS measurements and a standard laboratory. Patients were observed for 1 year in terms of clinical signs of decompensation.

RESULTS

One hundred fifty-nine of the initial 210 patients had a valid LS and SS measurement and were evaluable for clinical follow-up. Twelve patients developed a hepatic decompensation; with a SS >39 kPa (P=0.0005). Especially in a group with elevated LS, patients with a high risk of decompensation could be identified using SS. Patients with comparable LS who suffered from acute liver damage had significantly lower SS than respective patients with chronic liver damage (30.97 vs. 46.03 kPa; P=0.04). Acute liver failure was associated with elevated LS (16.47 kPa) but not with elevated SS (30.97 kPa).

CONCLUSIONS

The risk of a hepatic decompensation can easily be assessed using SS measurement. Therefore SS measurement might be a powerful screening tool identifying patients who need closer monitoring. Moreover, SS is able to differentiate between acute and chronic or acute on chronic liver damage.

Portal hypertension in hepatitis B-related cirrhosis: Diagnostic accuracy of liver and spleen stiffness by 2-D shear-wave elastography

AIM

To assess the diagnostic accuracy of liver and spleen stiffness measured by 2-D shear-wave elastography (SWE) in evaluation of clinically significant and severe portal hypertension (CSPH and SPH, respectively).

METHODS

Clinical data of 155 hepatitis B-related cirrhosis patients and their liver and spleen stiffness (L-SWE and S-SWE, respectively) were collected. The diagnostic performances of L-SWE, S-SWE, the liver stiffness-spleen diameter to platelet ratio score (LSPS) and portal hypertension risk score were evaluated.

RESULTS

One hundred and four patients were eligible for analysis. Clinically significant and severe PH were detected in 84 and 74 patients, respectively. Liver and spleen stiffness were significantly correlated with hepatic venous pressure gradient in overall, CSPH, and SPH groups (r_L  = 0.607, 0.554, and 0.412; r_S  = 0.665, 0.566, and 0.467, respectively; all P < 0.05). The area under the receiver operating characteristic curves of L-SWE, S-SWE, LSPS, and PH risk score were 0.72 (95% confidence interval [CI], 0.49-0.95), 0.81 (95% CI, 0.55-0.97), 0.76 (95% CI, 0.51-0.96), and 0.73 (95% CI, 0.55-0.88) for CSPH, and 0.77 (95% CI, 0.51-0.93), 0.85 (95% CI, 0.59-0.96), 0.80 (95% CI, 0.58-0.98), and 0.80 (95% CI, 0.59-0.93) for SPH. The best cut-off of L-SWE for determining CSPH and SPH were 16.1 kPa (sensitivity, 78%; specificity, 72%) and 23.5 kPa (sensitivity, 81%; specificity, 79%). For S-SWE, the best cut-offs were 25.3 kPa (sensitivity, 85%; specificity, 79%) and 33.4 kPa (sensitivity, 74%; specificity, 70%). A cut-off of L-SWE <13.2 kPa or S-SWE <23.2 kPa was able to rule out CSPH, whereas a cut-off of L-SWE >24.9 kPa or S-SWE >34.2 kPa was able to rule in CSPH.

CONCLUSIONS

Liver and spleen stiffness measured by 2-D SWE are reliable and promising non-invasive parameters to assess CSPH and SPH.

Liver Ultrasound Elastography: An Update to the World Federation for Ultrasound in Medicine and Biology Guidelines and Recommendations

The World Federation for Ultrasound in Medicine and Biology has produced these guidelines for the use of elastography techniques in liver diseases. For each available technique, the reproducibility, results and limitations are analyzed, and recommendations are given. This set of guidelines updates the first version, published in 2015. Since the prior guidelines, there have been several advances in technology. The recommendations are based on the international published literature, and the strength of each recommendation is judged according to the Oxford Centre for Evidence-Based Medicine. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of liver diseases.

Quantification of Liver Surface Nodularity at CT: Utility for Detection of Portal Hypertension

Purpose To determine whether quantification of liver surface nodularity (LSN) provides an estimate of the presence of clinically significant portal hypertension (CSPH) in patients with cirrhosis. Materials and Methods This retrospective study included a training cohort (n = 189) and separate external validation cohort (n = 78), both composed of patients with cirrhosis who underwent abdominal CT and hepatic venous pressure gradient (HVPG) measurement between 2010 and 2016. The LSN score, liver and spleen volumes, liver-to-spleen volume ratio, platelet count to spleen diameter ratio, Iranmanesh score, aspartate amino transferase-to-platelet ratio index, and Fibrosis-4 index were derived from CT images and serum laboratories. The accuracy of the various tests for predicting CSPH was evaluated with area under the receiver operating characteristic curve (AUROC) and compared by using the DeLong test. Student t test and Pearson correlation coefficient were used. Results One hundred eighty-nine patients were analyzed (119 men [mean age ± standard deviation, 57 years ± 11; range, 29-81 years] and 70 women [mean age, 61 years ± 10; range, 34-83 years]; overall mean age, 58 years ± 10; range, 29-83 years). A total of 102 patients (54%) had CSPH. LSN score correlated with HVPG (r = 0.75; P < .001). Patients with CSPH had a higher LSN score than did those without CSPH (3.2 ± 0.6 vs 2.4 ± 0.3; P < .001). A cutoff value of 2.8 had a positive predictive value of 88% for CSPH; the AUROC of LSN was 0.88 ± 0.03. This was higher than that of other available noninvasive tests (DeLong, all P < .001). In the validation cohort, LSN score of 2.8 had a positive predictive value of 86% for CSPH; the AUROC was 0.87 ± 0.04. Conclusion The CT-based liver surface nodularity score demonstrated high diagnostic performance for detecting clinically significant portal hypertension and outperformed multiple other noninvasive tests. © RSNA, 2018 Online supplemental material is available for this article.

Noninvasive Assessment of Portal Hypertension in Advanced Chronic Liver Disease: An Update

The assessment of portal hypertension is a relevant step in the evaluation of newly diagnosed advanced chronic liver disease (ACLD). The current gold standard includes the invasive evaluation of hepatic venous pressure gradient (HVPG) and endoscopy. However, noninvasive or minimally invasive techniques to assess portal hypertension have been proposed and well established. In the present manuscript, we review clinical studies on the use of noninvasive or minimally invasive techniques to assess portal hypertension in ACLD patients.

Managing portal hypertension in patients with liver cirrhosis

Portal hypertension is one cause and a part of a dynamic process triggered by chronic liver disease, mostly induced by alcohol or incorrect nutrition and less often by viral infections and autoimmune or genetic disease. Adequate staging - continuously modified by current knowledge - should guide the prevention and treatment of portal hypertension with defined endpoints. The main goals are interruption of etiology and prevention of complications followed, if necessary, by treatment of these. For the past few decades, shunts, mostly as intrahepatic stent bypass between portal and hepatic vein branches, have played an important role in the prevention of recurrent bleeding and ascites formation, although their impact on survival remains ambiguous. Systemic drugs, such as non-selective beta-blockers, statins, or antibiotics, reduce portal hypertension by decreasing intrahepatic resistance or portal tributary blood flow or by blunting inflammatory stimuli inside and outside the liver. Here, the interactions among the gut, liver, and brain are increasingly examined for new therapeutic options. There is no general panacea. The interruption of initiating factors is key. If not possible or if not possible in a timely manner, combined approaches should receive more attention before considering liver transplantation.

Quantitative and noninvasive assessment of chronic liver diseases using two-dimensional shear wave elastography

Two-dimensional shear wave elastography (2D-SWE) is a rapid, simple and novel noninvasive method that has been proposed for assessing hepatic fibrosis in patients with chronic liver diseases (CLDs) based on measurements of liver stiffness. 2D-SWE can be performed easily at the bedside or in an outpatient clinic and yields immediate results with good reproducibility. Furthermore, 2D-SWE was an efficient method for evaluating liver fibrosis in small to moderately sized clinical trials. However, the quality criteria for the staging of liver fibrosis are not yet well defined. Liver fibrosis is the main pathological basis of liver stiffness and a key step in the progression from CLD to cirrhosis; thus, the management of CLD largely depends on the extent and progression of liver fibrosis. 2D-SWE appears to be an excellent tool for the early detection of cirrhosis and may have prognostic value in this context. Because 2D-SWE has high patient acceptance, it could be useful for monitoring fibrosis progression and regression in individual cases. However, multicenter data are needed to support its use. This study reviews the current status and future perspectives of 2D-SWE for assessments of liver fibrosis and discusses the technical advantages and limitations that impact its effective and rational clinical use.

Non-invasive evaluation of portal hypertension using shear-wave elastography: analysis of two algorithms combining liver and spleen stiffness in 191 patients with cirrhosis

BACKGROUND

Two algorithms based on sequential measurements of liver and spleen stiffness using two-dimensional shearwave elastography (2D-SWE) have been recently proposed to estimate clinically significant portal hypertension (hepatic venous pressure gradient [HVPG] ≥10 mm Hg) in patients with cirrhosis, with excellent diagnostic accuracy.

AIM

To validate externally these algorithms in a large cohort of patients with cirrhosis.

METHODS

One hundred and ninety-one patients with stable cirrhosis (Child-Pugh class A 39%, B 29% and C 31%) who underwent liver and spleen stiffness measurements using 2D-SWE at the time of HVPG measurement were included. Diagnostic accuracy of the 2 algorithms was assessed by calculating sensitivity, specificity, positive and negative predictive values.

RESULTS

The first algorithm, using liver stiffness <16.0 kilopascals (kPa) and then spleen stiffness <26.6 kPa, was used to rule-out HVPG ≥10 mm Hg. In our population, its sensitivity and negative predictive value were 95% and 63% respectively. The second algorithm, using liver stiffness >38.0 kPa, or liver stiffness ≤38.0 kPa but spleen stiffness >27.9 kPa, was used to rule-in HVPG ≥10 mm Hg. In our population, its specificity and positive predictive value were 52% and 83% respectively. Restricting the analyses to the 74 patients without any history of decompensation of cirrhosis or to the 65 patients with highly reliable liver stiffness measurement did not improve the results.

CONCLUSION

In our population, diagnostic accuracies of non-invasive algorithms based on sequential measurements of liver and spleen stiffness using 2D-SWE were acceptable, but not good enough to replace HVPG measurement or to base clinical decisions.

Elastography methods for the non-invasive assessment of portal hypertension

The gold standard to assess the presence and severity of portal hypertension remains the hepatic vein pressure gradient, however the recent development of non-invasive assessment using elastography techniques offers valuable alternatives. In this review, we discuss the diagnostic accuracy and utility of such techniques in patients with portal hypertension due to cirrhosis. Areas covered: A literature search focused on liver and spleen stiffness measurement with different elastographic techniques for the assessment of the presence and severity of portal hypertension and oesophageal varices in people with chronic liver disease. The combination of elastography with parameters such as platelet count and spleen size is also discussed. Expert commentary: Non-invasive assessment of liver fibrosis and portal hypertension is a validated tool for the diagnosis and follow-up of patients. Baveno VI recommended the combination of transient elastography and platelet count for ruling out varices needing treatment in patients with compensated advanced chronic liver disease. Assessment of aetiology specific cut-offs for ruling in and ruling out clinically significant portal hypertension is an unmet clinical need. The incorporation of spleen stiffness measurements in non-invasive algorithms using validated software and improved measuring scales might enhance the non-invasive diagnosis of portal hypertension in the next 5 years.

Noninvasive Evaluation of Portal Hypertension Using a Supervised Learning Technique

Portal hypertension (PHT) is a key event in the evolution of different chronic liver diseases and leads to the morbidity and mortality of patients. The traditional reliable PHT evaluation method is a hepatic venous pressure gradient (HVPG) measurement, which is invasive and not always available or acceptable to patients. The HVPG measurement is relatively expensive and depends on the experience of the physician. There are many potential noninvasive methods to predict PHT, of which liver transient elastography is determined to be the most accurate; however, even transient elastography lacks the accuracy to be a perfect noninvasive diagnostic method of PHT. In this research, we are focusing on noninvasive PHT assessment methods that rely on selected best-supervised learning algorithms which use a wide set of noninvasively obtained data, including demographical, clinical, laboratory, instrumental, and transient elastography measurements. In order to build the best performing classification meta-algorithm, a set of 21 classification algorithms have been tested. The problem was expanded by selecting the best performing clinical attributes using algorithm-specific filtering methods that give the lowest error rate to predict clinically significant PHT. The suggested meta-algorithm objectively outperforms other methods found in literature and can be a good substitute for invasive PHT evaluation methods.

Non-invasive evaluation of portal hypertension using ultrasound elastography

Portal hypertension (PH) leads to serious complications, such as bleeding from gastroesophageal varices, ascites and portosystemic encephalopathy in patients with chronic liver disease (CLD). Gold standard methods for assessing PH and its complications include the measurement of hepatic venous pressure gradient and endoscopy; however, these are invasive, expensive and not available at all centres. Therefore, non-invasive alternatives have been the subject of extensive investigation over the last 20years. The present review focuses on the role of ultrasound elastography - a novel group of non-invasive techniques used to measure stiffness in target organs. In the context of CLD these methods are used to identify the presence of PH, its severity, and the risk of PH-related complications. The rationale, accumulated evidence, advantages and limitations of liver and spleen stiffness measurements evaluated by different ultrasound elastography techniques in patients with advanced CLD is discussed. Recent data regarding the use of ultrasound elastography techniques in patients with non-cirrhotic forms of PH are also described.

High risk of misinterpreting liver and spleen stiffness using 2D shear-wave and transient elastography after a moderate or high calorie meal

Food intake increases liver stiffness, but it is believed that liver stiffness returns to baseline two hours after a meal. The aim of this study was to investigate the impact of different sized meals on liver stiffness. Liver and spleen stiffness was measured with transient elastography (TE) and real-time 2-dimensional shear wave elastography (2D-SWE). Patients ingested a 625 kcal and a 1250 kcal liquid meal on two consecutive days. We measured liver and spleen elasticity, Controlled attenuation parameter (CAP) and portal flow at baseline and after 20, 40, 60, 120 and 180 minutes. Sixty patients participated, 83% with alcoholic liver disease. Twenty-eight patients had METAVIR fibrosis score F0-3 and 32 patients had cirrhosis. Liver stiffness, spleen stiffness and CAP increased after both meals for all stages of fibrosis. False positive 2D-SWE liver stiffness measurements caused 36% and 52% of patients with F0-3 fibrosis to be misclassified with higher stages of fibrosis after the moderate and high caloric meal. Likewise, 10% and 13% of compensated cirrhosis patients were misclassified with clinically significant portal hypertension after the two meals. We observed similar misclassification rates with TE. After three hours, liver stiffness remained elevated more than 20% from baseline in up to 50% of patients.

IN CONCLUSION

Liver stiffness, spleen stiffness and CAP increase after a meal across all stages of fibrosis and across elastography techniques. Up to half of patients may be misclassified with higher stages of fibrosis, if they are assessed after less than three hours fasting period.

Shear-wave elastography of the liver and spleen identifies clinically significant portal hypertension: A prospective multicentre study

BACKGROUND & AIMS

Clinically significant portal hypertension (CSPH) is associated with severe complications and decompensation of cirrhosis. Liver stiffness measured either by transient elastography (TE) or Shear-wave elastography (SWE) and spleen stiffness by TE might be helpful in the diagnosis of CSPH. We recently showed the algorithm to rule-out CSPH using sequential liver- (L-SWE) and spleen-Shear-wave elastography (S-SWE). This study investigated the diagnostic value of S-SWE for diagnosis of CSPH.

METHODS

One hundred and fifty-eight cirrhotic patients with pressure gradient measurements were included into this prospective multicentre study. L-SWE was measured in 155 patients, S-SWE in 112 patients, and both in 109 patients.

RESULTS

Liver-shear-wave elastography and S-SWE correlated with clinical events and decompensation. SWE of liver and spleen revealed strong correlations with the pressure gradient and to differentiate between patients with and without CSPH. The best cut-off values were 24.6 kPa:L-SWE and 26.3 kPa:S-SWE. L-SWE ≤16.0 kPa and S-SWE ≤21.7 kPa were able to rule-out CSPH. Cut-off values of L-SWE >29.5 kPa and S-SWE >35.6 kPa were able to rule-in CSPH (specificity >92%). Patients with a L-SWE >38.0 kPa had likely CSPH. In patients with L-SWE ≤38.0 kPa, a S-SWE >27.9 kPa ruled in CSPH. This algorithm has a sensitivity of 89.2% and a specificity of 91.4% to rule-in CSPH. Patients not fulfilling these criteria may undergo HVPG measurement.

CONCLUSIONS

Liver and spleen SWE correlate with portal pressure and can both be used as a non-invasive method to investigate CSPH. Even though external validation is still missing, these algorithms to rule-out and rule-in CSPH using sequential SWE of liver and spleen might change the clinical practice.