Diffusion-weighted MRI versus transient elastography in quantification of liver fibrosis in patients with chronic cholestatic liver diseases

Primary sclerosing cholangitis: Is qualitative and quantitative 3 T MR imaging useful for the evaluation of disease severity?

Purpose

To analyze the role of qualitative and quantitative 3 T MR imaging assessment as a non-invasive method for the evaluation of disease severity in patients with primary sclerosing cholangitis (PSC).

Methods

A series of 26 patients, with histological diagnosis of PSC undergoing 3 T MRI and hepatological evaluation, was retrospectively enrolled. All MR examinations included diffusion-weighted imaging (DWI), T2-weighted (T2w) and T1-weighted (T1w) sequences, before and after administration of Gd-EOB-DTPA with the acquisition of both dynamic and hepato-biliary phase (HBP). Qualitative analysis was performed by assessment of liver parenchyma and biliary tract changes, also including biliary excretion of gadoxetic acid on HBP. Quantitative evaluation was conducted on liver parenchyma by measurement of apparent diffusion coefficient (ADC) and relative enhancement (RE) on 3-minute delayed phase and on HBP. Results of blood tests (ALT, ALP, GGT, total and direct bilirubin, albumin, and platelets) and transient elastography-derived liver stiffness measurements (TE-LSM) were collected and correlated with qualitative and quantitative MRI findings.

Results

Among qualitative and quantitative findings, fibrosis visual assessment and RE had the best performance in estimating disease severity, showing a statistically significant correlation with both biomarkers of cholestasis and TE-LSM. Statistical analysis also revealed a significant correlation of gadoxetic acid biliary excretion with ALT and direct bilirubin, as well as of ADC with total bilirubin.

Conclusion

Qualitative and quantitative 3 T MR evaluation is a promising non-invasive method for the assessment of disease severity in patients with PSC.

Impact of velocity- and acceleration-compensated encodings on signal dropout and black-blood state in diffusion-weighted magnetic resonance liver imaging at clinical TEs

PURPOSE

The study aims to develop easy-to-implement concomitant field-compensated gradient waveforms with varying velocity-weighting (M1) and acceleration-weighting (M2) levels and to evaluate their efficacy in correcting signal dropouts and preserving the black-blood state in liver diffusion-weighted imaging. Additionally, we seek to determine an optimal degree of compensation that minimizes signal dropouts while maintaining blood signal suppression.

METHODS

Numerically optimized gradient waveforms were adapted using a novel method that allows for the simultaneous tuning of M1- and M2-weighting by changing only one timing variable. Seven healthy volunteers underwent diffusion-weighted magnetic resonance imaging (DWI) with five diffusion encoding schemes (monopolar, velocity-compensated (M1 = 0), acceleration-compensated (M1 = M2 = 0), 84%-M1-M2-compensated, 67%-M1-M2-compensated) at b-values of 50 and 800 s/mm2 at a constant echo time of 70 ms. Signal dropout correction and apparent diffusion coefficients (ADCs) were quantified using regions of interest in the left and right liver lobe. The blood appearance was evaluated using two five-point Likert scales.

RESULTS

Signal dropout was more pronounced in the left lobe (19%-42% less signal than in the right lobe with monopolar scheme) and best corrected by acceleration-compensation (8%-10% less signal than in the right lobe). The black-blood state was best with monopolar encodings and decreased significantly (p < 0.001) with velocity- and/or acceleration-compensation. The partially M1-M2-compensated encoding schemes could restore the black-blood state again. Strongest ADC bias occurred for monopolar encodings (difference between left/right lobe of 0.41 μm2/ms for monopolar vs. < 0.12 μm2/ms for the other encodings).

CONCLUSION

All of the diffusion encodings used in this study demonstrated suitability for routine DWI application. The results indicate that a perfect value for the level of M1-M2-compensation does not exist. However, among the examined encodings, the 84%-M1-M2-compensated encodings provided a suitable tradeoff.

Diagnostic accuracy of apparent diffusion coefficient values combined with γ-glutamyl transpeptidase-to-platelet ratio parameters for predicting hepatitis B-related fibrosis

OBJECTIVES

The accuracy of non-invasive liver fibrosis diagnosis based on the apparent diffusion coefficient (ADC) value combined with the γ-glutamyl transpeptidase-to-platelet ratio (GPR) model to predict the stage of hepatitis B-related fibrosis has not been reported. This study aimed to evaluate the diagnostic efficacy of ADC value combined with GPR for liver fibrosis grading.

METHODS

The data of 180 patients with chronic hepatitis B (CHB) diagnosed by liver biopsy were analyzed. The ADC value, GPR, and their combination were assessed in different cirrhosis stages using receiver operating characteristic curve analysis to evaluate their value in diagnosing liver fibrosis.

RESULTS

We observed that liver fibrosis stages were inversely associated with ADC values (r=-0.691, P<0.001), and positively associated with GPR (r=0.502, P<0.001). The area under the curve for diagnostic efficacy of ADC values, GPR, and their combination for F≥2 liver fibrosis was 0.831, 0.749, and 0.858, respectively, and for F≥3 was 0.872, 0.771, and 0.903, respectively. The diagnostic cutoffs of the combination for each stage were -7.07, -12.21 and -37.75, respectively.

CONCLUSIONS

The combined diagnostic tool of ADC and GPR may improve the accuracy of hepatitis B-related liver fibrosis diagnosis, especially for F≥3.

The diagnostic value of normalized ADC using spleen as reference organ in assessment liver fibrosis

Background

To investigate the value of liver ADC normalization using spleen as a reference organ in liver fibrosis assessment compared to Fibroscan.

A total of 60 participants were included, 30 HCV positive patients and 30 in control group. We calculated mean spleen apparent diffusion coefficient (ADC), liver mean ADC, and normalized liver ADC (defined as the ratio of liver ADC to spleen ADC) which were compared between cirrhotic patients and the control group. Data was analyzed, and ROC was used to evaluate the performance of nADC.

Results

No significant difference between spleen ADC values of patient and control groups or in-between different fibrosis stages. A negative correlation between liver ADC and nADC values with increasing fibrosis stages. We also found that the mean liver ADC and nADC value in patients with hepatic fibrosis were significantly lower than that of control group (1.53 × 10−3 mm2/s vs 1.65 × 10−3 mm2/s). After analysis with ROC, nADC shows higher diagnostic performance compared to liver ADC. nADC area under the curve (AUC) was 0.878 for detection of stage ≥ F2 with sensitivity and specificity of 87% and 80% respectively while ADC AUC was 0.548 with sensitivity and specificity of 62% and 72% respectively (p = 0.021); ≥ F3 AUC of nADC was 0.891 with sensitivity and specificity of 88.7% and 80% respectively while ADC AUC is 0.603 with sensitivity and specificity of 72% and 72% respectively (p = 0.023), and F4 stage nADC AUC was 0.879 for with sensitivity and specificity of 90% and 80% respectively, while ADC AUC was 0.648 with sensitivity and specificity of 80% and 72% respectively (p = 0.054).

Conclusion

Normalized liver ADC using the spleen as reference organs increases the diagnostic performance of MR in evaluation liver fibrosis compared to ADC alone.

Quantification of liver function using gadoxetic acid-enhanced MRI

The introduction of hepatobiliary contrast agents, most notably gadoxetic acid (GA), has expanded the role of MRI, allowing not only a morphologic but also a functional evaluation of the hepatobiliary system. The mechanism of uptake and excretion of gadoxetic acid via transporters, such as organic anion transporting polypeptides (OATP1,3), multidrug resistance-associated protein 2 (MRP2) and MRP3, has been elucidated in the literature. Furthermore, GA uptake can be estimated on either static images or on dynamic imaging, for example, the hepatic extraction fraction (HEF) and liver perfusion. GA-enhanced MRI has achieved an important role in evaluating morphology and function in chronic liver diseases (CLD), allowing to distinguish between the two subgroups of nonalcoholic fatty liver diseases (NAFLD), simple steatosis and nonalcoholic steatohepatitis (NASH), and help to stage fibrosis and cirrhosis, predict liver transplant graft survival, and preoperatively evaluate the risk of liver failure if major resection is planned. Finally, because of its noninvasive nature, GA-enhanced MRI can be used for long-term follow-up and post-treatment monitoring. This review article aims to describe the current role of GA-enhanced MRI in quantifying liver function in a variety of hepatobiliary disorders.

Magnetic Resonance imaging analysis of liver fibrosis and inflammation: overwhelming gray zones restrict clinical use

Magnetic resonance (MR) identification and grading of subjects with liver fibrosis and inflammation represents a clinical challenge. MR elastography plays a well-defined role in fibrosis estimation, but its use is not widely available in clinical settings. Given that liver MR is becoming the reference standard for fat and iron quantitation, there is a need to clarify whether there is any role for MR imaging in the concomitant evaluation of fibrosis and inflammation in this setting. This review summarizes the diagnostic estimations of different MR imaging parameters obtained from conventional non-contrast-enhanced multiple b values diffusion-weighted acquisitions, variable flip angles T1 relaxation maps and STIR images. Although some derived parameters have shown a significant correlation to histological scores, a small magnitude of effect with wide overlap across severity grades is the rule. Contrary to fat and iron quantification, the low precision and reproducibility of MR imaging metrics limits its clinical relevance in fibrosis and inflammation assessment. In a sequential clinical approach combining different methodologies, MR imaging has no applicability for ruling-out and low accuracy for ruling-in advanced fibrosis. Thereby, MR elastography remains as the only image method with high diagnostic accuracy for the detection of advanced fibrosis. Until date, inflammation remains in a gray zone where biopsy cannot be replaced, and further investigations are needed. The present review offers an in-depth discuss of the MR imaging diagnostic performance for the evaluation of liver fibrosis and inflammation, highlighting the need for scientific improvements.

Evolving role of magnetic resonance techniques in primary sclerosing cholangitis

Development of non-invasive methods to risk-stratify patients and predict clinical endpoints have been identified as one of the key research priorities in primary sclerosing cholangitis (PSC). In addition to serum and histological biomarkers, there has been much recent interest in developing imaging biomarkers that can predict disease course and clinical outcomes in PSC. Magnetic resonance imaging/magnetic resonance cholangiopancreatography (MRI/MRCP) continue to play a central role in the diagnosis and follow-up of PSC patients. Magnetic resonance (MR) techniques have undergone significant advancement over the last three decades both in MR data acquisition and interpretation. The progression from a qualitative to quantitative approach in MR acquisition techniques and data interpretation, offers the opportunity for the development of objective and reproducible imaging biomarkers that can potentially be incorporated as an additional endpoint in clinical trials. This review article will discuss how the role of MR techniques have evolved over the last three decades from emerging as an alternative diagnostic tool to endoscopic retrograde cholangiopancreatography, to being instrumental in the ongoing search for imaging biomarker of disease stage, progression and prognosis in PSC.

Transient elastography correlated with diffusion-weighted magnetic resonance imaging and cholestatic complications

BACKGROUND/PURPOSE

The study aim to investigate the correlation between diffusion-weighted magnetic resonance imaging (DW-MRI) and transient elastography (TE) liver fibrosis findings in children with cholestatic liver diseases, and the utility of TE findings to predict cholestatic complications in children.

METHODS

This cross-sectional study enrolled 36 cholestatic children (21 boys and 15 girls). All study subjects underwent TE and DW-MRI studies to assess liver stiffness. All study subjects were followed prospectively, and their cholestatic complications were analyzed. The optimum cut-off TE value for the prediction of cholestatic complications was determined by receiver operating characteristic (ROC) analysis.

RESULTS

A significant negative correlation between liver stiffness measurements (LSMs) and right-liver-to-psoas apparent diffusion coefficient ratios (LTPARs) was found in the study cohort (correlation coefficient = -0.52, p = 0.001). An LSM cut-off > 8.6 kPa was optimal for predicting complications of cholestasis in 6 months of this cohort (p < 0.001). Survival analysis revealed that an LSM of >8.6 kPa was significantly predictive of cholestatic complications in 6 months (hazard ratio = 4.89; 95% CI = 1.41-16.97; p = 0.01).

CONCLUSION

TE and DW-MRI findings showed a similar ability to predict liver fibrosis in cholestatic children. The LSMs measured by TE are predictive of the occurrence of cholestatic complications in 6 months in children with cholestatic liver diseases.

Prospective comparison of diffusion-weighted MRI and dynamic Gd-EOB-DTPA-enhanced MRI for detection and staging of hepatic fibrosis in primary sclerosing cholangitis

PURPOSE

To assess the diagnostic value of multiparametric magnetic resonance imaging (MRI) including dynamic Gd-EOB-DTPA-enhanced (DCE) and diffusion-weighted (DW) imaging for diagnosis and staging of hepatic fibrosis in primary sclerosing cholangitis (PSC) using transient elastography as a standard reference.

MATERIAL AND METHODS

Multiparametric MRI was prospectively performed on a 3.0-Tesla scanner in 47 patients (age 43.9±14.3 years). Transient elastography derived liver stiffness measurements (LSM), DCE-MRI derived parameters (hepatocellular uptake rate (Ki), arterial (Fa), portal venous (Fv) and total (Ft) blood flow, mean transit time (MTT), and extracellular volume (Ve)) and the apparent diffusion coefficient (ADC) were calculated. Correlation and univariate analysis of variance with post hoc pairwise comparison were applied to test for differences between LSM derived fibrosis stages (F0/F1, F2/3, F4). ROC curve analysis was used as a performance measure.

RESULTS

Both ADC and Ki correlated significantly with LSM (r= -0.614; p<0.001 and r= -0.368; p=0.01). The ADC significantly discriminated fibrosis stages F0/1 from F2/3 and F4 (p<0.001). Discrimination of F0/1 from F2/3 and F4 reached a sensitivity/specificity of 0.917/0.821 and 0.8/0.929, respectively. Despite significant inter-subject effect for classification of fibrosis stages, post hoc pairwise comparison was not significant for Ki (p>0.096 for F0/1 from F2/3 and F4). LSM, ADC and Ki were significantly associated with serum-based liver functional tests, disease duration and spleen volume.

CONCLUSION

DW-MRI provides a higher diagnostic performance for detection of hepatic fibrosis and cirrhosis in PSC patients in comparison to Gd-EOB-DTPA-enhanced DCE-MRI.

KEY POINTS

• Both ADC and hepatocellular uptake rate (Ki) correlate significantly with liver stiffness (r= -0.614; p<0.001 and r= -0.368; p=0.01). • The DCE-imaging derived quantitative parameter hepatocellular uptake rate (Ki) fails to discriminate pairwise intergroup differences of hepatic fibrosis (p>0.09). • DWI is preferable to DCE-imaging for discrimination of fibrosis stages F0/1 to F2/3 (p<0.001) and F4 (p<0.001).

Recommendations on the use of magnetic resonance imaging in PSC-A position statement from the International PSC Study Group

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disorder characterized by inflammation and fibrosis of the intra- and/or extrahepatic bile ducts. Magnetic resonance imaging (MRI) is a noninvasive imaging modality that can be used to diagnose PSC and detect disease related complications. Quantitative MRI technologies also have the potential to provide valuable prognostic information. Despite the potential of this imaging technology, the clinical application of MRI in the care of PSC patients and imaging standards vary across institutions. Moreover, a unified position statement about the role of MRI in the care of PSC patients, quality imaging standards, and its potential as a research tool is lacking.

CONCLUSION

Members of the International PSC Study Group and radiologists from North America and Europe have compiled the following position statement to provide guidance regarding the application of MRI in the care of PSC patients, minimum imaging standards, and future areas of research. (Hepatology 2017;66:1675-1688).

Liver fibrosis staging with diffusion-weighted imaging: a systematic review and meta-analysis

PURPOSE

A meta-analysis was performed to assess the diagnostic performance of diffusion-weighted imaging (DWI) in liver fibrosis (LF) staging.

METHODS

We conducted a comprehensive literature search to identify relevant articles. Diagnostic data were extracted for each METAVIR fibrosis stage (F0-F4). A bivariate binomial model was used to combine sensitivities and specificities. Summary receiver operating characteristics (SROC) curves were performed and areas under SROC curve (AUC) were calculated to indicate diagnostic accuracies. Subgroup analyses were performed between different study characteristics.

RESULTS

Twelve studies met the inclusion criteria for LF ≥F1, 16 for ≥F2, 18 for ≥F3, and 12 for F4. AUCs of DWI were 0.8554, 0.8770, 0.8836, and 0.8596 for ≥F1, ≥F2, ≥F3, and F4, respectively. Subgroup analyses showed that for LF ≥F2 and ≥F3, maximal b values (b max) ≥ 800 s/mm2 performed significantly better than b max < 800 s/mm2. The diagnostic accuracies of 3.0 T and intravoxel incoherent motion (IVIM)-DWI were significantly higher than those of 1.5 T and conventional DWI for diagnosing liver cirrhosis (F4).

CONCLUSIONS

DWI is a reliable noninvasive technique with good diagnostic accuracy for LF staging. Using b max ≥ 800 s/mm2, high-field strength (3.0 T) and IVIM-DWI can optimize the diagnostic performance of DWI.

Technical advancements and protocol optimization of diffusion-weighted imaging (DWI) in liver

An area of rapid advancement in abdominal MRI is diffusion-weighted imaging (DWI). By measuring diffusion properties of water molecules, DWI is capable of non-invasively probing tissue properties and physiology at cellular and macromolecular level. The integration of DWI as part of abdominal MRI exam allows better lesion characterization and therefore more accurate initial diagnosis and treatment monitoring. One of the most technical challenging, but also most useful abdominal DWI applications is in liver and therefore requires special attention and careful optimization. In this article, the latest technical developments of DWI and its liver applications are reviewed with the explanations of the technical principles, recommendations of the imaging parameters, and examples of clinical applications. More advanced DWI techniques, including Intra-Voxel Incoherent Motion (IVIM) diffusion imaging, anomalous diffusion imaging, and Diffusion Kurtosis Imaging (DKI) are discussed.

Assessing hepatic fibrosis: comparing the intravoxel incoherent motion in MRI with acoustic radiation force impulse imaging in US

OBJECTIVES

This study compared the diagnostic performance of intravoxel incoherent motion (IVIM) in magnetic resonance imaging (MRI) and acoustic radiation force impulse imaging (ARFI) in ultrasound (US) for liver fibrosis (LF) evaluation.

METHODS

A total of 49 patients scheduled for liver surgery were recruited. LF in the non-tumorous liver parenchyma at the right lobe was estimated using a slow diffusion coefficient, fast diffusion coefficient (D fast), perfusion fraction (f) of the IVIM parameters, the total apparent diffusion coefficient of conventional diffusion-weighted imaging and the shear wave velocity (Vs) of ARFI. LF was graded using the Metavir scoring system on histological examination. The Spearman rank correlation coefficient for correlation and analysis of variance was used for determining difference. The diagnostic performance was compared using receiver operating characteristic curve analysis.

RESULTS

LF exhibited significant correlation with the three parameters D fast, f, and Vs (r = -0.528, -0.337, and 0.481, respectively, P < 0.05). The D fast values in the F4 group were significantly lower than those in the F0, F1 and F2 groups. D fast exhibited a non-inferior performance for diagnosing all fibrosis grades compared with that of Vs.

CONCLUSIONS

Both IVIM and ARFI provide reliable estimations for the noninvasive assessment of LF.

KEY POINTS

• Liver fibrosis can be diagnosed and graded using noninvasive imaging modalities. • ARFI and IVIM can be incorporated into routine examinations. • IVIM can differentiate liver cirrhosis from none to moderate liver fibrosis. • The diagnostic performances of IVIM and ARFI are equal.

Functional MR imaging of the abdomen

In this article, functional magnetic resonance (MR) imaging techniques in the abdomen are discussed. Diffusion-weighted imaging (DWI) increases the confidence in detecting and characterizing focal hepatic lesions. The potential uses of DWI in kidneys, adrenal glands, bowel, and pancreas are outlined. Studies have shown potential use of quantitative dynamic contrast-enhanced MR imaging parameters, such as K(trans), in predicting outcomes in cancer therapy. MR elastography is considered to be a useful tool in staging liver fibrosis. A major issue with all functional MR imaging techniques is the lack of standardization of the protocol.

Apparent diffusion coefficient value of hepatic fibrosis and inflammation in children with chronic hepatitis

PURPOSE

This study was done to prospectively evaluate the usefulness of apparent diffusion coefficient (ADC) in the diagnosis and grading of hepatic fibrosis and inflammation in children with chronic hepatitis.

MATERIALS AND METHODS

Institutional Review Board approval was obtained. This prospective study was carried out on 50 children with chronic hepatitis (mean age 8.3 ± 3.2 years; 33 boys and 17 girls) and 20 age- and sex-matched healthy control children. The children underwent diffusion-weighted magnetic resonance imaging of the liver. The ADC value of the liver was calculated. The hepatic fibrosis stages (F1-F6) and necroinflammatory activity grades (A1-A4) were calculated. The ADC values of different stages of hepatic fibrosis and grades of necroinflammatory activity were calculated.

RESULTS

The mean ADC value of the liver parenchyma was 1.53 ± 0.17 × 10(-3) mm(2)/s in children with chronic hepatitis and 1.74 ± 0.16 × 10(-3) mm(2)/s in controls. The ADC value was significantly lower in children with hepatic fibrosis compared to controls (p = 0.001). There was a significant difference (p = 0.001) in ADC between mild (F1-F3) and advanced (F4-F6) stages of fibrosis. There was a significant difference (p = 0.004) in ADC between mild (A1-A2) and advanced (A3-A4) grades of necroinflammation. The cut-off ADC values used to differentiate mild from advanced fibrosis and necroinflammation were 1.62 and 1.64 mm(2)/s with an area under the curve of 0.898 and 0.807, respectively. The ADC value negatively correlated with stages of hepatic fibrosis (r = -0.799, p = 0.001) and necroinflammatory activity grade (r = -0.468, p = 0.001).

CONCLUSIONS

We conclude that ADC value is an effective noninvasive parameter for the diagnosis and grading of hepatic fibrosis and inflammation in children with chronic hepatitis.

Spatial characterization of corneal biomechanical properties with optical coherence elastography after UV cross-linking

Corneal collagen cross-linking (CXL) is a clinical treatment for keratoconus that structurally reinforces degenerating ocular tissue, thereby limiting disease progression. Clinical outcomes would benefit from noninvasive methods to assess tissue material properties in affected individuals. Regional variations in tissue properties were quantified before and after CXL in rabbit eyes using optical coherence elastography (OCE) imaging. Low-amplitude (<1µm) elastic waves were generated using micro air-pulse stimulation and the resulting wave amplitude and speed were measured using phase-stabilized swept-source OCE. OCE imaging following CXL treatment demonstrates increased corneal stiffness through faster elastic wave propagation speeds and lower wave amplitudes.

Diffusion-weighted imaging of the liver: an update

Diffusion-weighted magnetic resonance imaging (DW-MRI) is now widely used as a standard imaging sequence for evaluation of the liver. The technique is easy to implement across different MRI platforms, and results in enhanced disease detection and characterization. With careful implementation, the quantitative apparent diffusion coefficient derived shows good measurement reproducibility, which can be applied for tissue characterization, the assessment of tumour response and disease prognostication. There is now a body of evidence that highlights the relative strengths and limitations of the technique for the assessment of liver diseases. The potential for more sophisticated analysis of DW-MRI data is currently being widely investigated.

Doppler ultrasound of hepatic blood flow for noninvasive evaluation of liver fibrosis compared with liver biopsy and transient elastography

BACKGROUND

Accurate quantification of liver fibrosis is essential for therapeutic decision-making and follow-up of chronic liver diseases.

AIMS

To optimize the quality of non-invasive assessment of liver fibrosis in patients with chronic hepatopathy we compared Doppler ultrasound with liver histology and transient elastography (TE).

METHODS

In this prospective observational study, we performed Doppler ultrasound of hepatic blood vessels as well as TE in 125 patients who underwent liver biopsy for diagnostic work-up of hepatopathy. Hepatic venous flow was evaluated by determining resistance index (HVRI) of the right hepatic vein. Doppler and TE results were compared with histological staging, grading and degree of steatosis obtained by liver biopsy.

RESULTS

HVRI showed a high reliability in predicting fibrosis stage FII or higher (AUROC 93.7 %, HVRI < 1.185; sensitivity 89.66 % and specificity 86.32 %) and was superior to TE. Neither steatosis nor inflammation had significant influence on HVRI-based estimation of fibrosis (1.45 ± 0.2; 1.26 ± 0.05; 1.06 ± 0.06; 0.87 ± 0.08; 0.46 ± 0.11 for F0-FIV, respectively). HVRI differed significantly in different stages of fibrosis. In contrast, portal vein and hepatic artery only showed significant changes in higher stages of fibrosis. Hepatic artery resistance index was elevated (0.67-0.74; p < 0.05); portal vein flow maximum and undulation were significantly reduced in higher fibrosis (p < 0.05 and p < 0.01, respectively).

CONCLUSIONS

Hepatic blood flow analysis, especially HVRI, provides useful information during assessment of hepatopathy and is a reliable predictor of liver fibrosis stage FII or higher as part of the non-invasive diagnostic work-up and follow-up in chronic liver disease.