Significance of liver stiffness measurement by acoustic radiation force impulse (ARFI) among hepatitis C patients

Comparison of 2-D Shear Wave Elastography and Point Shear Wave Elastography for Assessing Liver Fibrosis

Progressive liver fibrosis may result in cirrhosis, portal hypertension and increased risk of hepatocellular carcinoma. We performed a meta-analysis to compare liver fibrosis staging in chronic liver disease patients using 2-D shear wave elastography (2-D SWE) and point shear wave elastography (pSWE). The PubMed, Web of Science and Cochrane Library databases were searched until May 31, 2020 for studies evaluating the diagnostic performance of 2-D SWE and pSWE in assessing liver fibrosis. Pooled sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratios and area under receiver operating characteristic curve were estimated using the bivariate random effects model. As a result, 71 studies with 11,345 patients were included in the analysis. The pooled sensitivities of 2-D SWE and pSWE significantly differed for the detection of significant fibrosis (F ≥ 2; 0.84 vs. 0.76, p < 0.001) and advanced fibrosis (F ≥ 3; 0.90 vs. 0.83, p = 0.003), but not for detection of cirrhosis (F = 4; 0.89 vs. 0.85, p = 0.090). The pooled specificities of 2-D SWE and pSWE did not significantly differ for detection of F ≥ 2 (0.81 vs. 0.79, p = 0.753), F ≥ 3 (0.87 vs. 0.83, p = 0.163) or F = 4 (0.87 vs. 0.84, p = 0.294). Both 2-D SWE and pSWE have high sensitivity and specificity for detecting each stage of liver fibrosis. Two-dimensional SWE has higher sensitivity than pSWE for detection of significant fibrosis and advanced fibrosis.

Quantitative Elastography Methods in Liver Disease: Current Evidence and Future Directions

Chronic liver diseases often result in the development of liver fibrosis and ultimately, cirrhosis. Treatment strategies and prognosis differ greatly depending on the severity of liver fibrosis, thus liver fibrosis staging is clinically relevant. Traditionally, liver biopsy has been the method of choice for fibrosis evaluation. Because of liver biopsy limitations, noninvasive methods have become a key research interest in the field. Elastography enables the noninvasive measurement of tissue mechanical properties through observation of shear-wave propagation in the tissue of interest. Increasing fibrosis stage is associated with increased liver stiffness, providing a discriminatory feature that can be exploited by elastographic methods. Ultrasonographic (US) and magnetic resonance (MR) imaging elastographic methods are commercially available, each with their respective strengths and limitations. Here, the authors review the technical basis, acquisition techniques, and results and limitations of US- and MR-based elastography techniques. Diagnostic performance in the most common etiologies of chronic liver disease will be presented. Reliability, reproducibility, failure rate, and emerging advances will be discussed. ^© RSNA, 2018 Online supplemental material is available for this article.

Clinical usefulness and performance of acoustic radiation force impulse in patients with chronic hepatitis B

AIM

The aim of this study was to evaluate the performance of acoustic radiation force impulse (ARFI) compared with liver biopsy in quantifying fibrosis levels in patients with chronic hepatitis B (CHB).

PATIENTS AND METHODS

The study was approved by the institutional review board at our hospital. One hundred CHB patients and 30 healthy controls (130 individuals) were included in the study. ARFI measurements were performed on all of these cases. CHB was diagnosed when serum hepatitis surface antigen was positive for more than 6 months and when persistent or intermittent elevations in alanine aminotransferase and aspartate aminotransferase levels and histopathological changes in liver biopsy were present. Liver biopsies were taken as a reference standard for 100 CHB patients. Liver biopsy samples were examined using the Ishak scoring system and compared with ARFI velocity values.

RESULTS

Of the 130 participants, 107 (82.3%) were men and 23 (17.7%) were women. Thirty of these participants were healthy controls and their fibrotic score was evaluated as an Ishak fibrosis score of 0. A gradual increase in the mean velocity value was obtained for fibrosis scores F0-F6 (Ishak fibrosis score) in our study. A strong positive correlation was found between the mean velocity values and fibrosis scores of liver biopsy that were performed on liver segment 8. The area under the receiver operating characteristic curve was used to detect the best cutoff velocity values, and no or mild fibrosis (F≤2), significant fibrosis (F≥3), and severe fibrosis (F≥5) were calculated to be 0.95, 1.75, and 2.55 m/s, respectively. When a cutoff value of 1.75 m/s was used, ARFI had a sensitivity of 83% and a specificity of 98% in differentiating patients with fibrosis score F≤2 versus F≥3.

CONCLUSION

ARFI elastography in patients with CHB can be considered an easy-to-use and accurate noninvasive tool to evaluate the severity of liver fibrosis.

Virtual Touch™ Quantification to Diagnose and Monitor Liver Fibrosis in Hepatitis B and Hepatitis C: A NICE Medical Technology Guidance

Virtual Touch™ Quantification (VTq) is a software application used with Siemens Acuson ultrasound scanners to assess the stiffness of liver tissue. The National Institute for Health and Care Excellence (NICE) Medical Technologies Advisory Committee (MTAC) selected VTq for evaluation and invited the company to submit clinical and economic evidence. King's Technology Evaluation Centre, an External Assessment Centre (EAC) commissioned by NICE, independently assessed the evidence submitted. The EAC conducted its own systematic review, meta-analysis and economic analysis to supplement the company's submitted evidence. The meta-analyses comparing VTq and transient elastography (TE) with liver biopsy (LB) provided pooled estimates of liver stiffness and stage of fibrosis for the study populations (hepatitis B, hepatitis C or combined populations). When comparing significant fibrosis (Metavir score F ≥ 2) for both hepatitis B and C, VTq had slightly higher values for both sensitivity and specificity (77 and 81 %) than TE (76 and 71 %). The overall prevalence of cirrhosis (F4, combined populations) was similar with VTq and TE (23 vs. 23 %), and significant fibrosis (F ≥ 2) was lower for VTq than for TE (55 vs. 62 %). The EAC revised the company's de novo cost model, which resulted in a cost saving of £53 (against TE) and £434 (against LB). Following public consultation, taking into account submitted comments, NICE Medical Technology Guidance MTG27 was published in September 2015. This recommended the adoption of the VTq software to diagnose and monitor liver fibrosis in patients with hepatitis B or hepatitis C.

Low Pretreatment Acoustic Radiation Force Impulse Imaging (ARFI) Values Predict Sustained Virological Response in Antiviral Hepatitis C Virus (HCV) Therapy

Background

Non-invasive procedures such as acoustic radiation force impulse imaging (ARFI) shear-wave elastography are currently used for the assessment of liver fibrosis. In the course of chronic hepatitis C, significant liver fibrosis or cirrhosis develops in approximately 25% of patients, which is a negative predictor of antiviral treatment response. Cirrhosis can be prevented by successful virus elimination.

In this prospective study, a pretreatment ARFI cutoff value of 1.5 m/s was evaluated in relation to sustained virological response to anti-HCV therapy.

Material/Methods

In 23 patients with chronic hepatitis C, liver stiffness was examined with ARFI at defined times before and under antiviral triple therapy (peginterferon, ribavirin in combination with a first-generation protease inhibitor, and telaprevir or boceprevir). Patients were stratified into 2 groups based on pretreatment ARFI values (<1.5 m/s and ≥1.5 m/s) for the assessment of virological response.

Results

The liver stiffness at baseline for all patients was 1.57±0.79 m/s (ARFI median ± standard deviation; margin: 0.81 m/s to 3.45 m/s). At week 4 of triple therapy, patients with low pretreatment ARFI values had higher rates of HCV-RNA negativity (69% vs. 43%), reflecting an early rapid virological response (eRVR). Sustained virological response (SVR) was found in 75% (12/16) of patients with an ARFI value <1.5 m/s and only 57% (4/7) of patients with ARFI value ≥1.5 m/s.

Conclusions

Patients with chronic hepatitis C and pretreatment ARFI <1.5 m/s showed earlier virus elimination and better response to treatment.

Changes of shear-wave velocity by interferon-based therapy in chronic hepatitis C

AIM

To evaluate the changes of shear-wave velocity (Vs) by acoustic radiation force impulse after treatment in chronic hepatitis C.

METHODS

Eighty-seven patients with chronic hepatitis C were consecutively treated with combinations of interferon (IFN) plus ribavirin (RBV). Vs value (m/s) was measured with acoustic radiation force impulse before treatment, at end of treatment (EOT), 1 year after EOT, and 2 years after EOT.

RESULTS

In patients with a sustained virological response (SVR) (n = 41), Vs significantly decreased at EOT [1.19 (1.07-1.37), P = 0.0004], 1 year after EOT [1.10 (1.00-1.22), P = 0.0001], and 2 years after EOT [1.05 (0.95-1.16), P < 0.0001] compared with baseline [1.27 (1.11-1.49)]. In patients with a relapse (n = 26), Vs did not significantly decrease at EOT [1.23 (1.12-1.55)], 1 year after EOT [1.20 (1.12-1.80)], and 2 years after EOT [1.41 (1.08-2.01)] compared with baseline [1.39 (1.15-1.57)]. In patients with a nonvirological response (n = 20), Vs did not significantly decrease at EOT [1.64 (1.43-2.06)], 1 year after EOT [1.66 (1.30-1.95)], and 2 years after EOT [1.61 (1.36-2.37)] compared with baseline [1.80 (1.54-2.01)]. Among genotype 1 patients, baseline Vs was significantly lower in SVR patients [1.28 (1.04-1.40)] than in non-SVR patients [1.56 (1.20-1.83)] (P = 0.0142).

CONCLUSION

Reduction of Vs values was shown in SVR patients after IFN-plus-RBV therapy by acoustic radiation force impulse.

Acoustic radiation force impulse elastography for non-invasive assessment of disease stage in patients with primary biliary cirrhosis: A preliminary study

AIM

To investigate the diagnostic performance of the acoustic radiation force impulse (ARFI) elastography for the assessment of primary biliary cirrhosis (PBC) stage.

MATERIALS AND METHODS

Sixty-one patients with PBC in which liver biopsy and ARFI elastography measurements were performed in the same session were included in the study. The diagnostic performance of ARFI elastography for predicting the PBC stage was determined from the area under receiver operating characteristics (AUROC) curve analysis.

RESULTS

ARFI elastography correlated significantly with histological stage (r = 0.74, p < 0.001) in patients with PBC. The AUROC of ARFI elastography for predicting histological stage equal to or higher than II, III, and equal to IV were 0.83, 0.93, and 0.91, respectively. The optimal cut-off values of ARFI elastography were 1.51 m/s, 1.79 m/s, and 2.01 m/s for PBC stage equal to or higher than II, III, and equal to IV, respectively.

CONCLUSION

ARFI elastography is an acceptable and powerful technique for quantitative assessment of PBC stage.