Palm-Sized Wireless Transient Elastography System with Real-Time B-Mode Ultrasound Imaging Guidance: Toward Point-of-Care Liver Fibrosis Assessment

Transient elastography (TE), recommended by the WHO, is an established method for characterizing liver fibrosis via liver stiffness measurement (LSM). However, technical barriers remain towards point-of-care application, as conventional TE requires wired connections, possesses a bulky size, and lacks adequate imaging guidance for precise liver localization. In this work, we report the design, phantom validation, and clinical evaluation of a palm-sized TE system that enables simultaneous B-mode imaging and LSM. The performance of this system was validated experimentally using tissue-equivalent reference phantoms (1.45-75 kPa). Comparative studies against other liver elastography techniques, including conventional TE and two-dimensional shear wave elastography (2D-SWE), were performed to evaluate its reliability and validity in adults with various chronic liver diseases. Intra- and inter-operator reliability of LSM were established by an elastography expert and a novice. A good agreement was observed between the Young's modulus reported by the phantom manufacturer and this system (bias: 1.1-8.6%). Among 121 patients, liver stiffness measured by this system and conventional TE were highly correlated (r = 0.975) and strongly agreed with each other (mean difference: -0.77 kPa). Inter-correlation of this system with conventional TE and 2D-SWE was observed. Excellent-to-good operator reliability was demonstrated in 60 patients (ICCs: 0.824-0.913). We demonstrated the feasibility of employing a fully integrated phased array probe for reliable and valid LSM, guided by real-time B-mode imaging of liver anatomy. This system represents the first technical advancement toward point-of-care liver fibrosis assessment. Its small footprint, along with B-mode guidance capability, improves examination efficiency and scales up screening for liver fibrosis.

Liver T1/T2 values with cardiac MRI during respiration

BACKGROUND

Assessing the hepatic status of children with CHD is very important in the post-operative period. This study aimed to assess the usefulness of paediatric liver T1/T2 values and to evaluate the impact of respiration on liver T1/T2 values.

METHODS

Liver T1/T2 values were evaluated in 69 individuals who underwent cardiac MRI. The mean age of the participants was 16.2 ± 9.8 years. Two types of imaging with different breathing methods were possible in 34 participants for liver T1 values and 10 participants for liver T2 values.

RESULTS

The normal range was set at 620-830 msec for liver T1 and 25-40 ms for liver T2 based on the data obtained from 17 healthy individuals. The liver T1/T2 values were not significantly different between breath-hold and free-breath imaging (T1: 769.4 ± 102.8 ms versus 763.2 ± 93.9 ms; p = 0.148, T2: 34.9 ± 4.0 ms versus 33.6 ± 2.4 ms; p = 0.169). Higher liver T1 values were observed in patients who had undergone Fontan operation, tetralogy of Fallot operation, or those with chronic viral hepatitis. There was a trend toward correlation between liver T1 values and liver stiffness (R = 0.65, p = 0.0004); and the liver T1 values showed a positive correlation with the shear wave velocity (R = 0.62, p = 0.0006).

CONCLUSIONS

Liver T1/T2 values were not affected by breathing patterns. Because liver T1 values tend to increase with right heart overload, evaluation of liver T1 values during routine cardiac MRI may enable early detection of future complications.

Correlation of Liver Elastography as a Predictor of Esophageal Varices and Its Comparison With Ultrasound Abdomen and Liver Function Tests in Patients With Chronic Liver Disease

INTRODUCTION

Variceal haemorrhage is a life-threatening complication that occurs in up to 40% of patients with chronic liver disease including cirrhosis. It is associated with a mortality rate of 20% with each episode of variceal bleeding. Esophagogastroduodenoscopy is the gold standard for the detection of esophageal varices but is an invasive procedure and not very cost-effective. Our study was designed to correlate the presence of esophageal varices on endoscopy with the liver stiffness measurement using liver elastography in patients with chronic liver disease. We also compared various non-invasive predictors like laboratory parameters and ultrasound features and correlated them with the presence of varices in patients with chronic liver disease.

METHODOLOGY

This prospective observational study was conducted in a tertiary-care hospital in South India from November 2017 to April 2019. All patients with chronic liver disease were subjected to endoscopy, and the presence of esophageal varices and their grading was noted. The predictive efficacy of ultrasound elastography using Toshiba Aplio 500 ultrasound two-dimensional shear wave elastography (2D-SWE) in predicting esophageal varices was calculated and compared with the efficacy of predicting esophageal varices by other non-invasive parameters like laboratory investigations, abdominal ultrasound, and liver scores like Child-Turcotte-Pugh (CTP) score, model for end-stage liver disease (MELD) score, fibrosis 4 (FIB-4) score, aspartate aminotransferase-to-platelet ratio index (APRI) score, and aspartate aminotransferase/alanine aminotransferase ratio (AAR).

RESULTS

The study included a total of 168 patients out of which 57% (96 patients) had no varices. About 52 patients (72.2%) had F1/Grade I varices, 9 (12.5%) had F2/Grade II varices, and 11 (15.3%) had F3/Grade III varices. The greatest predictive value for esophageal varices was liver stiffness with a diagnostic accuracy of 81.7%. Ultrasound features like coarse echotexture of the liver (66.7%), splenomegaly (67%), dilated portal vein (78.6%), and presence of moderate ascites (66.7%) had a significant statistical association with the presence of esophageal varices. Laboratory parameters like thrombocytopenia of less than 1.5 lakhs/cu.mm (52.8%), albumin <3 g/dL (60.4%), and reversal of albumin/globulin ratio (52.4%) were significant predictors of esophageal varices. The odds ratio for significant scores in predicting oesophageal varices using binary logistic regression was significant in patients whose liver elastography grade was more than F4, CTP score was B, MELD score was >11, and FIB-4 scores was >3.25 and between 1.46 and 3.25.

CONCLUSION

Liver elastography is a non-invasive procedure that can be a useful tool in predicting esophageal varices in chronic liver disease. Other non-invasive predictors like ultrasound abdomen and laboratory parameters can also be considered a replacement for repeated invasive endoscopy, thus facilitating early intervention and avoiding unfavourable outcomes in patients with chronic liver disease.

Phase-regularized and displacement-regularized compressed sensing for fast magnetic resonance elastography

Liver magnetic resonance elastography (MRE) is a noninvasive stiffness measurement technique that captures the tissue displacement in the phase of the signal. To limit the scanning time to a single breath-hold, liver MRE usually involves advanced readout techniques such as simultaneous multislice (SMS) or multishot methods. Furthermore, all these readout techniques require additional in-plane acceleration using either parallel imaging capabilities, such as sensitivity encoding (SENSE), or k -space undersampling, such as compressed sensing (CS). However, these methods apply a single regularization function on the complex image. This study aims to design and evaluate methods that use separate regularization on the magnitude and phase of MRE to exploit their distinct spatiotemporal characteristics. Specifically, we introduce two compressed sensing methods. The first method, termed phase-regularized compressed sensing (PRCS), applies a two-dimensional total variation (TV) prior to the magnitude and two-dimensional wavelet regularization to the phase. The second method, termed displacement-regularized compressed sensing (DRCS), exploits the spatiotemporal redundancy using 3D total variation on the magnitude. Additionally, DRCS includes a displacement fitting function to apply wavelet regularization to the displacement phasor. Both DRCS and PRCS were evaluated with different levels of compression factors in three datasets: an in silico abdomen dataset, an in vitro tissue-mimicking phantom, and an in vivo liver dataset. The reconstructed images were compared with the full sampled reconstruction, zero-filling reconstruction, wavelet-regularized compressed sensing, and a low rank plus sparse reconstruction. The metrics used for quantitative evaluation were the structural similarity index (SSIM) of magnitude (M-SSIM), displacement (D-SSIM), and shear modulus (S-SSIM), and mean shear modulus. Results from highly undersampled in silico and in vitro datasets demonstrate that the DRCS method provides higher reconstruction quality than the conventional compressed sensing method for a wide range of stiffness values. Notably, DRCS provides 24% and 22% increase in D-SSIM compared with CS for the in silico and in vitro datasets, respectively. Comparison with liver stiffness measured from full sampled data and highly undersampled data (CR=4) demonstrates that the DRCS method provided the strongest correlation ( R 2 =0.95), second-lowest mean bias (-0.18 kPa, lowest for CS with -0.16 kPa), and lowest coefficient of variation (CV=3.6%). Our results demonstrate the potential of using DRCS to improve the reconstruction quality of accelerated MRE.

Significant Association between Subclinical Left Cardiac Dysfunction and Liver Stiffness in Metabolic Syndrome Patients with Diabetes Mellitus and Non-Alcoholic Fatty Liver Disease

Background and Objectives: Diabetes mellitus (DM) is connected to both cardiovascular disease and non-alcoholic fatty liver disease (NAFLD), and is an important component of metabolic syndrome (MetS). NAFLD can be detected and quantified using the vibration controlled transient elastography (VCTE) and the controlled attenuation parameter (CAP), whereas traditional and two-dimensional speckle tracking echocardiography (2D-STE) can reveal subclinical abnormalities in heart function. We sought to see if there was a link between left cardiac dysfunction and different levels of hepatic fibrosis in MetS patients with DM and NAFLD. Patients and Methods: We recruited successive adult subjects with MetS and a normal left ventricular ejection fraction, who were divided into two groups according to the presence or absence of DM. The presence of NAFLD was established by CAP and VCTE, while conventional and 2D-STE were used to assess left heart's systolic and diastolic function. The mean age of the MetS subjects was 62 ± 10 years, 82 (55%) were men. The distribution of liver steatosis severity was similar among diabetics and non-diabetics, while liver fibrosis grade 2 and 3 was significantly more frequent in diabetics (p = 0.02, respectively p = 0.001). LV diastolic dysfunction was found in 52% of diabetic and in 36% of non-diabetic MetS patients (p = 0.04). 2D-STE identified in the diabetic subjects increased LA stiffness (40% versus 24%, p = 0.03) and reduced global left ventricular longitudinal strain (47% versus 16%, p < 0.0001). Liver fibrosis grade ≥ 2 was identified as an independent predictor of both subclinical LV systolic dysfunction and of LA dysfunction in MetS patients with DM (p < 0.0001). Conclusions: The current investigation confirms the link between liver stiffness and subclinical cardiac dysfunction as detected by 2D-STE in MetS patients with DM. The novel parameters derived from LA and LV 2D-STE have demonstrated greater sensitivity compared to the older measurements, and a substantial connection with hepatic fibrosis.

Comparison of point-shear wave elastography (ElastPQ) and transient elastography (FibroScan) for liver fibrosis staging in patients with non-alcoholic fatty liver disease

BACKGROUND AND AIMS

ElastPQ is a point shear wave elastography technique used to non-invasively assess liver fibrosis. We compared liver stiffness measurements (LSM) by ElastPQ and fibroscan transient elastography (F-TE) in a cohort of patients with non-alcoholic fatty liver disease (NAFLD). We further evaluated the performance of ElastPQ in a subgroup of patients with available liver histology.

MATERIALS AND METHODS

We included patients with NAFLD who presented in a dedicated multidisciplinary clinic. Anthropometric parameters, blood tests and elastography measurements were obtained using F-TE and ElastPQ as part of routine clinical care.

RESULTS

We enrolled 671 patients with NAFLD, mean age 55.8 ± 13 years, body mass index (BMI) 31.5 ± 5.7 kg/m² , 56.6% males, 41% diabetes, 53.7% hypertension, 68% dyslipidaemia. ElastPQ showed an excellent correlation with F-TE (Spearman's r = 0.80, p < .001), which was better for mild/moderate stages of fibrosis. Independent predictors of a >2 kPa discrepancy between the two techniques were a larger waist circumference and F-TE ≥10 kPa. In the subgroup of 159 patients with available histology, ElastPQ showed similar diagnostic accuracy with F-TE in staging liver fibrosis (ElastPQ area under the curves 0.84, 0.83, 0.86 and 0.95, for F ≥ 1, F ≥ 2, F ≥ 3 and F = 4 respectively). Optimal cut-off values of ElastPQ for individual fibrosis stages were lower than those of F-TE.

CONCLUSIONS

ElastPQ shows an excellent correlation with F-TE in patients with NAFLD, which was better for lower LSM. The optimal cut-off values of ElastPQ are lower than those of F-TE for individual stages of fibrosis. ElastPQ has similar diagnostic accuracy to F-TE for all stages of fibrosis.

Fibrosis Predictive Score in Caucasian Patients with Metabolic Syndrome

INTRODUCTION

Many of the patients presenting with metabolic syndrome (MetS) also have liver steatosis (NAFLD) and some of them could develop liver fibrosis.

PURPOSE

To develop a simple score that could rule out fibrosis, especially significant fibrosis (F≥2) and could be used in daily practice in patients with MetS, in order to identify patients at risk.

PATIENTS AND METHODS

A total of 204 patients with MetS were prospectively enrolled. Evaluation of liver fibrosis was made using Vibration Controlled Transient Elastography while evaluation of steatosis was achieved using ultrasound (US).

RESULTS

Out of 204 patients with MetS, 179 patients (87.7%) had reliable liver stiffness measurements and 22.9% (41/179) had F ≥2. To formulate the fibrosis predicting score, all clinical variables associated with F ≥2 in the univariate analysis were considered in a multivariate regression model. According to the power of correlation, by consensus, we attributed 1 point for BMI >31.4 kg/m², 1 point for female gender, 1 point for HDLc <47mg/dL, 1 point for mild steatosis at US, 1.5 point for moderate and 2 points for severe steatosis.

CONCLUSION

At an optimal cut-off value of <3.5, our score could be used to rule-out the risk for developing at least significant fibrosis with a high negative predictive value (NPV 89.2%) in patients with MetS.

Liver Elastography as a Predictor of Esophageal Varices in Patients With Cirrhosis

Introduction

Liver cirrhosis is an advanced consequence of a long-standing liver disease that can lead to portal hypertension which subsequently can manifest as life-threatening variceal bleeding. The present study aimed to determine liver stiffness by shear wave elastography (SWE) to predict esophageal varices (EV) in patients with chronic liver diseases.

Methodology

A prospective observational study was performed at the Department of Hepatogastroenterology, Sindh Institute of Urology and Transplantation, Karachi between November 2020 and July 2021. Individuals aged between 18 and 50 years, irrespective of gender, with diagnosed chronic liver disease >6 months were eligible to partake in the study. Patients with concomitant renal failure, severe ascites, severe life-threatening co-morbidities including congestive heart failure NYHA-III and IV, acute asthmatic attack, and recent myocardial infarction (MI) were excluded from the study. SWE was determined in all patients to measure liver stiffness. Esophagogastroduodenoscopy (EGD) was performed to visualize the esophageal varices. All findings were recorded. A 2 × 2 table was applied to determine the sensitivity, specificity, positive, and diagnostic accuracy for SWE by taking endoscopy as the definitive test.

Results

A total of 204 patients were included in the study. Mean age of 40.37 ± 15.20 years was observed. The mean liver size of patients was 12.38 ± 2.06 cm and the mean liver stiffness of patients was 19.97 ± 8.6. The sensitivity and specificity of liver elastography were 44.90% and 51.90%, respectively. Furthermore, the positive and negative predictive values were 53.00% and 99.39%, respectively. The diagnostic accuracy of the test was 51.86%.

Conclusion

Even though the diagnostic gold standard for the detection of varices is EGD, liver elastography provides a less invasive procedure to assess for varices in patients with cirrhotic liver disease. The present study concluded that liver elastography is a non-invasive and indirect valuable tool to predict the presence of esophageal varices with sensitivity and specificity of 44.90% and 51.90%, respectively.

Acoustic radiation force impulse elastography and liver fibrosis risk scores in severe obesity

Objective

Identifying significant fibrosis is crucial to evaluate the prognosis and therapeutic interventions in patients with nonalcoholic fatty liver disease (NAFLD). We assessed the performance of acoustic radiation force impulse (ARFI) elastography, APRI, FIB-4, Forns, NFS and BARD scores in determining liver fibrosis in severe obesity.

Methods

A prospective study included 108 patients undergoing bariatric surgery. Liver biopsy specimens were obtained intraoperatively and classified according to the NAFLD Activity Score. Patients were assessed with serological markers and shear wave velocity of the liver was measured with the Siemens S2000 ultrasound system preoperatively. Optimal cut-off values were determined using the area under the receiver operating characteristic curves (AUROC).

Results

In the entire cohort prevalence of NAFLD was 80.6%, steatohepatitis 25.9% and significant fibrosis 19.4%. The best tests for predicting significant fibrosis were FIB-4 and Forns scores (both AUROC 0.78), followed by APRI (AUROC 0.74), NFS (AUROC 0.68), BARD (AUROC 0.64) and ARFI (AUROC 0.62). ARFI elastography was successful in 73% of the patients. Higher body mass index (BMI) correlated with invalid ARFI measurements. In patients with BMI < 42 kg/m², ARFI showed 92.3% sensitivity and 82,6% specificity for the presence of significant fibrosis, with AUROC 0.86 and cut-off 1.32 m/s.

Conclusion

FIB-4 and Forns scores were the most accurate for the prediction of significant fibrosis in bariatric patients. Applicability and accuracy of ARFI was limited in individuals with severe obesity. In patients with BMI < 42 kg/m², ARFI elastography was capable for predicting significant fibrosis with relevant accuracy.

A Multidisciplinary Approach to Evaluate the Presence of Hepatic and Cardiac Abnormalities in Patients with Post-Acute COVID-19 Syndrome-A Pilot Study

(1) Background: Patients suffering from the novel coronavirus 2019 (COVID-19) disease could experience several extra-pulmonary involvements, including cardiovascular complications and liver injury. This study aims to evaluate the presence of cardiac and liver alterations in patients with post-acute COVID-19 syndrome using transthoracic echocardiography (TTE) and liver elastography (LE). (2) Methods: A total of 97 subjects recovering from COVID-19, attending the hospital's specialized outpatient clinic for persisting symptoms at 3 to 11 weeks after the acute illness, were included in this study. They all had a basal COVID-19 assessment, and subsequently, a clinical evaluation, laboratory tests, TTE, and LE. (3) Results: considering the presence of pulmonary injury during COVID-19, patients were divided into two groups. Although none of them had altered systolic function, we evidenced pulmonary hypertension, diastolic dysfunction, increased liver stiffness, viscosity, and steatosis in around one-third of the patients, with significantly higher values in subjects with pulmonary injury compared to those without. (4) Conclusion: persisting symptoms characterizing the post-acute COVID-19 syndrome could be explained by residual cardiac and hepatic lesions, which were worse in more severe COVID-19 forms. These patients may be at risk of developing liver fibrosis and cardiac alterations and should be investigated in the first 12 weeks after the onset of the infection.

Significant Association Between Left Ventricular Diastolic Dysfunction, Left Atrial Performance and Liver Stiffness in Patients with Metabolic Syndrome and Non-Alcoholic Fatty Liver Disease

PURPOSE

The constitutive elements of the metabolic syndrome (MetS) are linked with both non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease. Controlled attenuation parameter (CAP), and vibration controlled transient elastography (VCTE), are able to detect and quantify NAFLD, while conventional and two-dimensional speckle tracking echocardiography (2D-STE) is capable to identify subclinical changes in cardiac function. We wanted to evaluate whether there is any correspondence between left ventricular (LV) diastolic dysfunction and different degrees of liver steatosis and fibrosis in MetS subjects with NAFLD.

PATIENTS AND METHODS

A total of 150 adult subjects having MetS and a normal left ventricular (LV) systolic function were recorded in the study, while 150 age- and sex- matched adults without MetS were enrolled as controls. NAFLD was established by VCTE and CAP. The left heart systolic and diastolic function was evaluated by conventional and 2D-ST echocardiography. Left atrial (LA) stiffness was calculated as the ratio between the E/A ratio and the LA reservoir-strain.

RESULTS

In univariate regression analysis, the variables associated with LV diastolic dysfunction in MetS patients were: liver steatosis grade ≥2, liver fibrosis grade ≥2, the longitudinal LA peak strain during the reservoir phase, the LA strain rate during ventricular contraction and the LA stiffness. In multivariate logistic regression, two variables were selected as independent predictors of LV diastolic dysfunction, namely the liver stiffness (P=0.0003) and the LA stiffness (P<0.0001). LA stiffness predicted subclinical LV diastolic dysfunction in MetS patients with a sensitivity of 45% and a specificity of 96% when using a cut-off value >0.38, and was significantly correlated with liver steatosis stage ≥2 and liver fibrosis stage ≥2.

CONCLUSION

The present study confirms the association between liver stiffness, LA stiffness and LV diastolic dysfunction in MetS patients. Our study suggests that liver elastography and 2D-STE should become habitual assessments in MetS patients.

Chronic Viral Hepatitis in a Cohort of Inflammatory Bowel Disease Patients from Southern Italy: A Case-Control Study

We performed an epidemiologic study to assess the prevalence of chronic viral hepatitis in inflammatory bowel disease (IBD) and to detect their possible relationships. Methods: It was a single centre cohort cross-sectional study, during October 2016 and October 2017. Consecutive IBD adult patients and a control group of non-IBD subjects were recruited. All patients underwent laboratory investigations to detect chronic hepatitis B (HBV) and C (HCV) infection. Parameters of liver function, elastography and IBD features were collected. Univariate analysis was performed by Student's t or chi-square test. Multivariate analysis was performed by binomial logistic regression and odds ratios (ORs) were calculated. We enrolled 807 IBD patients and 189 controls. Thirty-five (4.3%) had chronic viral hepatitis: 28 HCV (3.4%, versus 5.3% in controls, p = 0.24) and 7 HBV (0.9% versus 0.5% in controls, p = 0.64). More men were observed in the IBD-hepatitis group (71.2% versus 58.2%, p < 0.001). Patients with IBD and chronic viral hepatitis had a higher mean age and showed a higher frequency of diabetes, hypertension and wider waist circumference. They suffered more frequently from ulcerative colitis. Liver stiffness was greater in subjects with IBD and chronic viral hepatitis (7.0 ± 4.4 versus 5.0 ± 1.2 KPa; p < 0.001). At multivariate analysis, only old age directly correlated with viral hepatitis risk (OR = 1.05, 95%CI 1.02-1.08, p < 0.001). In conclusion, the prevalence of HBV/HCV in IBD is low in our region. Age may be the only independent factor of viral hepatitis-IBD association. Finally, this study firstly measured liver stiffness in a large scale, showing higher values in subjects with both diseases.

Optimization of Point-Shear Wave Elastography by Skin-to-Liver Distance to Assess Liver Fibrosis in Patients Undergoing Bariatric Surgery

Background: Obesity is a primary limiting factor in liver stiffness measurement (LSM). The impact of obesity has always been evaluated in terms of body mass index (BMI), without studying the effects of skin-to-liver distance (SLD) on LSM. We studied the impact of SLD on LSM in a cohort of obese patients undergoing bariatric surgery and intra-operatory liver biopsy. Materials and Methods: 299 patients underwent LSM by point-shear wave elastography (ElastPQ protocol), with two different ultrasound machines. SLD was measured as the distance between the skin and the liver capsule, perpendicular to where the region of interest (ROI) was positioned. We used the following arbitrary cut-offs: <5.7 kPa, F0–1; 5.7–7.99 kPa, F2; ≥8 kPa, F3–4. Results: We developed two logistic regression models using elastography–histology agreement (EHA) as the dependent variable and SLD as the independent variable. The model based on the second machine showed strongly more performant discriminative and calibration metrics (AIC 38.5, BIC 44.2, Nagelkerke Pseudo-R2 0.894, AUROC 0.90). The SLD cut-off value of 34.5 mm allowed a correct EHA with a sensitivity of 100%, a specificity of 93%, negative predictive value of 100%, positive predictive value of 87%, an accuracy of 96%, and positive likelihood ratio of 3.56. Conclusion: The impact of SLD is machine-dependent and should be taken into consideration when interpreting LSM. We believe that our findings may serve as a reference point for appropriate fibrosis stratification by liver elastography in obese patients.

The Importance of Transaminases Flare in Liver Elastography: Characterization of the Probability of Liver Fibrosis Overestimation by Hepatitis C Virus-Induced Cytolysis

BACKGROUND

Liver stiffness measurement (LSM) is crucial for appropriate fibrosis staging in patients with ongoing hepatitis C virus (HCV) infection. However, there is still an ongoing debate on the impact of serum transaminases (aspartate-aminotransferase, AST; alanine-aminotransferase, ALT) on LSM.

METHODS

We selected 110 patients undergoing HCV eradication therapy with LSM compatible with significant liver fibrosis. LSM was evaluated prior to therapy and one year after HCV eradication.

RESULTS

LSM showed a median decrease of 35% from baseline values, and 67 (61%) patients showed posttreatment values compatible with lower fibrosis stages. We developed two logistic regression models to determine the probability of liver fibrosis overestimation according to serum transaminase. The probability of overestimation of two or more fibrosis grade is equal to (1) 50% for AST of 99 IU/L (2.2 ULN) and ALT of 90.5 IU/L (2 ULN), (2) 80% for AST of 123.5 IU/L (2.74 ULN) and ALT of 101.5 IU/L (2.25 ULN), and (3) reaches 100% for AST of 211 IU/L (4.7 ULN) and ALT of 140 IU/L (3.1 ULN).

CONCLUSIONS

This study highlights the impact of serum transaminases on LSM. We believe that our findings may serve as a reference point for appropriate fibrosis stratification by liver elastography in patients with HCV infection.

Randomized Clinical Trial: Bergamot Citrus and Wild Cardoon Reduce Liver Steatosis and Body Weight in Non-diabetic Individuals Aged Over 50 Years

Background: Non-alcoholic fatty liver disease is the most common cause of liver-related morbidity and mortality in the world. However, no effective pharmacological treatment for this condition has been found. Purpose: This study evaluated the effect of a nutraceutical containing bioactive components from Bergamot citrus and wild cardoon as a treatment for individuals with fatty liver disease. The primary outcome measure was the change in liver fat content. Methods: A total of 102 patients with liver steatosis were enrolled in a double-blind placebo controlled clinical trial. The intervention group received a nutraceutical containing a Bergamot polyphenol fraction and Cynara Cardunculus extract, 300 mg/day for 12 weeks. The control group received a placebo daily. Liver fat content, by transient elastography, serum transaminases, lipids and glucose were measured at the baseline and the end of the study. Results: We found a greater liver fat content reduction in the participants taking the nutraceutical rather than placebo (-48.2 ± 39 vs. -26.9 ± 43 dB/m, p = 0.02); The percentage CAP score reduction was statistically significant in those with android obesity, overweight/obesity as well as in women. However, after adjustment for weight change, the percentage CAP score reduction was statistically significant only in those over 50 years (44 vs. 78% in placebo and nutraceutical, respectively, p = 0.007). Conclusions: This specific nutraceutical containing bioactive components from Bergamot and wild cardoon reduced the liver fat content during 12 weeks in individuals with liver steatosis over 50 years. If confirmed, this nutraceutical could become the cornerstone treatment of patients affected by liver steatosis. Clinical Trial Registration: www.isrctn.com, identifier ISRCTN12833814.

Association Between Subclinical Left Ventricular Myocardial Systolic Dysfunction Detected by Strain and Strain‑Rate Imaging and Liver Steatosis and Fibrosis Detected by Elastography and Controlled Attenuation Parameter in Patients with Metabolic Syndrome

PURPOSE

The components of metabolic syndrome (MS) are risk factors for developing both cardiovascular disease (CVD) and non-alcoholic fatty liver disease (NAFLD). Strain (SI) and strain‑rate imaging (SRI) are able to recognize early changes in cardiac function. Vibration-controlled transient elastography (VCTE) and controlled attenuation parameter (CAP) detect and quantify liver fibrosis and steatosis. We aimed to assess whether there is any correlation between liver fibrosis and steatosis and left ventricular (LV) dysfunction in MS patients.

PATIENTS AND METHODS

A total of 150 adults with MS were registered in the study. They were compared with a control group of 150 age- and sex-matched adults without MS. After the classic echocardiographic assessment of LV function, two-dimensional speckle echocardiography (2D-STE) was used to evaluate LV peak systolic strain (S) and peak systolic strain rate (SR), while liver steatosis and fibrosis were evaluated by VCTE and CAP.

RESULTS

LV diastolic dysfunction was significantly more frequent among the patients with MS. We found significant differences between the two groups regarding the presence of subtle LV systolic dysfunction, detected by reduced values of S and SR. The risk for LV diastolic dysfunction was 3.6 times higher in MS with severe steatosis and 8 times higher in patients with severe fibrosis, P<0.0001. The risk for LV systolic dysfunction was double in MS with severe steatosis and 1.7 times higher in MS with severe fibrosis, P<0.0001.

CONCLUSION

In MS patients with normal LV ejection fraction, conventional echocardiography parameters identified diastolic LV dysfunction, while SI and SRI identified subtle impairment of systolic LV dysfunction. The presence of hepatic steatosis and fibrosis increases significantly the risk for cardiac dysfunction in MS patients (P<0.0001).

Magnetic resonance imaging of obesity and metabolic disorders: Summary from the 2019 ISMRM Workshop

More than 100 attendees from Australia, Austria, Belgium, Canada, China, Germany, Hong Kong, Indonesia, Japan, Malaysia, the Netherlands, the Philippines, Republic of Korea, Singapore, Sweden, Switzerland, the United Kingdom, and the United States convened in Singapore for the 2019 ISMRM-sponsored workshop on MRI of Obesity and Metabolic Disorders. The scientific program brought together a multidisciplinary group of researchers, trainees, and clinicians and included sessions in diabetes and insulin resistance; an update on recent advances in water-fat MRI acquisition and reconstruction methods; with applications in skeletal muscle, bone marrow, and adipose tissue quantification; a summary of recent findings in brown adipose tissue; new developments in imaging fat in the fetus, placenta, and neonates; the utility of liver elastography in obesity studies; and the emerging role of radiomics in population-based "big data" studies. The workshop featured keynote presentations on nutrition, epidemiology, genetics, and exercise physiology. Forty-four proffered scientific abstracts were also presented, covering the topics of brown adipose tissue, quantitative liver analysis from multiparametric data, disease prevalence and population health, technical and methodological developments in data acquisition and reconstruction, newfound applications of machine learning and neural networks, standardization of proton density fat fraction measurements, and X-nuclei applications. The purpose of this article is to summarize the scientific highlights from the workshop and identify future directions of work.

Long-term changes in liver elasticity in hepatitis C virus-infected patients with sustained virologic response after treatment with direct-acting antivirals

Background

The use of interferon-free direct-acting antiviral agents (DAAs) is associated with a rapid short-term decrease in liver stiffness in chronic hepatitis C-infected patients with sustained virologic response (SVR).

Objective

The objective of this article is to evaluate long-term changes in liver elasticity in hepatitis C patients with SVR using transient elastography (TE), FIB-4 and APRI.

Methods

A total of 143 patients were treated with DAAs and reached SVR. Patients received TE measurement (median (range)) at treatment start (baseline), follow-up week 24 (FU24) and follow-up week 96 (FU96). Laboratory data were examined at each date and FIB-4 and APRI were calculated.

Results

Liver elasticity showed a significant decrease from baseline to FU24 (13.1 (3.1-75) kPa to 9.3 (2.9-69.1) kPa; p < 0.0001) and declined further until FU96 (7.9 (2.4-59.3) kPa; p < 0.0001). Liver inflammation and liver function parameters normalised during long-term follow-up. Progression of liver stiffness between FU24 to FU96 despite viral clearance was observed in 24 patients (17%). Long-term liver stiffness progression was associated with aspartate aminotransferase levels and TE change from baseline to FU24.

Conclusion

During long-term follow-up, the majority of patients with SVR had further improved liver stiffness values. Still, a significant proportion of patients may show long-term liver stiffness progression and thus continued TE follow-up is recommended.

Probe Oscillation Shear Wave Elastography: Initial In Vivo Results in Liver

Shear wave elastography methods are able to accurately measure tissue stiffness, allowing these techniques to monitor the progression of hepatic fibrosis. While many methods rely on acoustic radiation force to generate shear waves for 2-D imaging, probe oscillation shear wave elastography (PROSE) provides an alternative approach by generating shear waves through continuous vibration of the ultrasound probe while simultaneously detecting the resulting motion. The generated shear wave field in in vivo liver is complicated, and the amplitude and quality of these shear waves can be influenced by the placement of the vibrating probe. To address these challenges, a real-time shear wave visualization tool was implemented to provide instantaneous visual feedback to optimize probe placement. Even with the real-time display, it was not possible to fully suppress residual motion with established filtering methods. To solve this problem, the shear wave signal in each frame was decoupled from motion and other sources through the use of a parameter-free empirical mode decomposition before calculating shear wave speeds. This method was evaluated in a phantom as well as in in vivo livers from five volunteers. PROSE results in the phantom as well as in vivo liver correlated well with independent measurements using the commercial General Electric Logiq E9 scanner.

Acoustic radiation force impulse (ARFI) elastography in a cohort of alpha-1 antitrypsin-deficient individuals and healthy volunteers

Background

Acoustic radiation force impulse (ARFI) elastography has been used to assess liver stiffness non-invasively. However, its usefulness in alpha-1 antitripsin-deficient (AATD) individuals is unknown.

Purpose

To assess if liver fibrosis is present in a cohort of AATD individuals using ARFI elastography.

Material and Methods

Eighty-three participants aged 38–39 years, except for two who were aged 40 years, underwent ultrasound elastography of the liver with ARFI technique. Twenty-nine were homozygote ZZ genotype, PiZZ (14 men, 15 women); 12 were SZ genotype, Pi SZ (8 men, 4 women), and 42 were healthy volunteers, PiMM (16 men, 26 women). Three specific liver anatomical regions were examined: segments 2/3 (left lobe) in the subcostal plane, and 5/6 and 7/8 (right lobe) in the intercostal space. In each region, three measurements were registered.

Results

There was no statistically significant difference between ARFI-median in the AATD group and the control group (P value = 0.877) and neither between AATD groups (PiZZ and PiSZ) with a P value = 0.259. The ARFI-median was lower in the right liver lobe than in the left lobe in all groups and the difference between both lobes was statistically significant (P = 0.001). No statistically significant difference was found in ARFI-median of the right liver lobe between the AATD group and the control group (P = 0.759), nor between the AATD group (P = 0.384). No gender difference was found in ARFI-median.

Conclusions

ARFI values in AATD individuals aged 38–39 years showed no difference compare to healthy participants.

Intestinal microbiota in patients with chronic hepatitis C with and without cirrhosis compared with healthy controls

BACKGROUND & AIMS

The importance of the intestinal microbiota for the onset and clinical course of many diseases, including liver diseases like non-alcoholic steatohepatitis and cirrhosis, is increasingly recognized. However, the role of intestinal microbiota in chronic hepatitis C virus (HCV) infection remains unclear.

METHODS

In a cross-sectional approach, the intestinal microbiota of 95 patients chronically infected with HCV (n=57 without cirrhosis [NO-CIR]; n=38 with cirrhosis [CIR]) and 50 healthy controls (HC) without documented liver diseases was analysed.

RESULTS

Alpha diversity, measured by number of phylotypes (S) and Shannon diversity index (H'), decreased significantly from HC to NO-CIR to CIR. S and H' correlated negatively with liver elastography. Analysis of similarities revealed highly statistically significant differences in the microbial communities between HC, NO-CIR and CIR (R=.090; P<1.0×10^-6 ). Stratifying for HCV genotypes even increased the differences. In addition, we observed distinct patterns in the relative abundance of genera being either positive or negative correlated with diseases status.

CONCLUSIONS

This study shows that not only the stage of liver disease but also HCV infection is associated with a reduced alpha diversity and different microbial community patterns. These differences might be caused by direct interactions between HCV and the microbiota or indirect interactions facilitated by the immune system.

Gas6 as a putative noninvasive biomarker of hepatic fibrosis

AIM

To evaluate serum growth arrest-specific gene 6 (Gas6) concentration as a biomarker of liver fibrosis progression.

MATERIALS & METHODS

One hundred and thirteen consecutive patients affected by chronic liver disease underwent transient elastography, Gas6 measurement and, if clinically indicated, liver biopsy.

RESULTS

Gas6 concentration was directly correlated to liver stiffness (r = 0.67; p < 0.0001) and was significantly higher in patients with advanced fibrosis (Ishak 4-5; p < 0.001). A plasma concentration <30 ng/ml Gas6 ruled out fibrosis with 84% sensitivity and 56% specificity, while values >42 ng/ml identified severe fibrosis with a sensitivity of 64% and a specificity of 95%; the diagnostic accuracy was comparable to that of transient elastography.

CONCLUSION

Gas6 is a novel biomarker of liver fibrosis, with a potential clinical and pathophysiological relevance.

Prevalence and prognostic value of hepatic histological alterations in patients with Crohn's disease

Variable degrees of liver histological changes in patients with Crohn's disease (CD) have been reported.

OBJECTIVE

To evaluate the liver histological alterations and their prognostic significance in patients affected by CD without abnormalities of liver biochemical parameters and ultrasound features.

MATERIAL AND METHODS

A prospective, single-blind study, including 35 consecutive patients with CD that underwent bowel resection with a contemporary performance of liver biopsy from 1992 to 2003.

EXCLUSION CRITERIA

the presence of standard causes of liver disease, such as alcohol consumption exceeding 20 g/day, primary sclerosing cholangitis, viral infections, celiac disease, metabolic syndrome and alterations of the metabolism. Patients were followed up with regular evaluation of hepatic cytolysis, cholestasis, synthesis and ultrasound performance. After a mean interval of 14 years (from May to December 2013), liver fibrosis was assessed by Fibroscan®.

RESULTS

Histological alterations were shown in 60% of patients, without serious liver injuries (no case of inflammation or significant fibrosis). Fibroscan® was performed in 33 subjects and no significant changes were observed (mean value of liver stiffness: 5.2 ± 1.2 kPa). The minimal microscopic damage did not evolve either in patients with a normal histology or in those with an altered histology at baseline (p = 0.9). Only patients who took azathioprine had a statistically significant increase of liver stiffness values (5.7 ± 1.5 kPa vs 4.7 ± 1.3 kPa, p = 0.017).

CONCLUSIONS

Patients with CD do not need additional examinations compared to the general population, unless clinical or biochemical abnormalities are found.

Liver stiffness measurements and short-term survival after left ventricular assist device implantation: A pilot study

BACKGROUND

Hepatic dysfunction can contribute to the clinical outcome of patients with end-stage chronic heart failure (HF). This pilot study evaluated the importance of liver stiffness (LS) measurements by acoustic radiation force impulse (ARFI) imaging elastography in patients with end-stage chronic HF who underwent left ventricular assist device (LVAD) implantation.

METHODS

The study enrolled 28 patients (23 men), mean age of 54 ± 11 years, with end-stage chronic HF selected for LVAD implantation. At baseline, all patients received LS measurements using ARFI elastography. Hepatic venous pressure gradient measurements and transjugular liver biopsies were performed in 16 patients. Liver stiffness was measured 21 days (Follow-up 1, n = 23) and 485 ± 136 days (Follow-up 2, n = 13) after LVAD implantation. Patients were classified according to their baseline LS into Group I (low baseline LS [no significant fibrosis = Metavir F < 2]) or Group II (high baseline LS [significant fibrosis = Metavir F ≥ 2]).

RESULTS

LS at baseline was higher in Group II than in Group I (p < 0.001) and decreased significantly after LVAD implantation (Follow-up 1, p = 0.002; Follow-up 2, p = 0.002). Baseline LS correlated with liver fibrosis (p = 0.049) and central venous pressure (p = 0.001). Non-survivors showed higher LS (p = 0.019), bilirubin (p = 0.018), Model for End-Stage Liver Disease score (p = 0.001), and liver fibrosis (p = 0.004) compared with the survivors. In the univariate analysis, LS was a significant factor (p = 0.017) in predicting survival after LVAD implantation.

CONCLUSIONS

ARFI elastography shows that LS is influenced by central venous congestion and histologic changes of the liver in patients with end-stage chronic HF. LS may predict the outcome in patients after LVAD implantation.