https://aasldpubs.onlinelibrary.wiley.com/doi/pdf/10.1002/hep.22759

Diagnosis, management, and treatment of hepatitis C: An update

Review of recent research on hepatitis C therapy for 54th annual meeting of the American association for the study of liver diseases

Global Prevalence of Helicobacter pylori Infection: Systematic Review and Meta-Analysis

https://www.journal-of-hepatology.eu/article/S0168-8278(15)00259-7/pdf

EASL-ALEH Clinical Practice Guidelines: Non-invasive tests for evaluation of liver disease severity and prognosis.

Elastography-based imaging techniques have received substantial attention in recent years for non-invasive assessment of tissue mechanical properties. These techniques take advantage of changed soft tissue elasticity in various pathologies to yield qualitative and quantitative information that can be used for diagnostic purposes. Measurements are acquired in specialized imaging modes that can detect tissue stiffness in response to an applied mechanical force (compression or shear wave). Ultrasound-based methods are of particular interest due to its many inherent advantages, such as wide availability including at the bedside and relatively low cost. Several ultrasound elastography techniques using different excitation methods have been developed. In general, these can be classified into strain imaging methods that use internal or external compression stimuli, and shear wave imaging that use ultrasound-generated traveling shear wave stimuli. While ultrasound elastography has shown promising results for non-invasive assessment of liver fibrosis, new applications in breast, thyroid, prostate, kidney and lymph node imaging are emerging. Here, we review the basic principles, foundation physics, and limitations of ultrasound elastography and summarize its current clinical use and ongoing developments in various clinical applications.

Ultrasound Elastography: Review of Techniques and Clinical Applications

Acoustic Radiation Force Impulse elastography for fibrosis evaluation in patients with chronic hepatitis C: an international multicenter study.

Purpose To compare two methods of noninvasive assessment: transient elastography (TE) and acoustic radiation force impulse elastography (ARFI) Patients and methods Our study included 114 subjects: 38 healthy volunteers, (considered to have no fibrosis - F 0) and 76 patients with chronic liver disease: 53 who had undergone liver biopsy (LB) (7 with F 1, 24 with F 2, 22 with F 3 Metavir) and 23 previously diagnosed with cirrhosis (F4 Metavir) In each patient we performed a liver stiffness measurement by means of TE and ARFI ARFI (shear wave velocity quantification) was performed at 3 points: at 0 - 1 cm, at 1 - 2 cm and at 2 - 3 cm under the capsule For each depth, 5 valid measurements were made, and a median value was calculated, measured in m/sec Results A direct, strong, linear correlation (Spearman rho = 0848) was found between TE and the stage of fibrosis (p 0), TE had the best predictive value: optimized cut-off 565 kPa (AUROC -0898) For ARFI, the cut-offs were: 14 m/sec, AUROC -0747 (1 - 2 cm), and 126 m/sec AUROC -0721 (2 - 3 cm) For predicting cirrhosis (F = 4 Metavir), the optimized cut-offs were: TE -129 kPa (AUROC -0994); ARFI - 178 m/sec for measurements made 2 - 3 cm below the capsule, AUROC - 0951 Conclusion At present, liver elasticity evaluation by means of ARFI is not superior to TE for the assessment of liver fibrosis For ARFI, the most reliable results are obtained if measurements are made 1 - 2 and 2 - 3 cm below the liver capsule ARFI is an accurate test for the diagnosis of cirrhosis

Acoustic radiation force impulse elastography as compared to transient elastography and liver biopsy in patients with chronic hepatopathies.

Our study assessed acoustic radiation force impulse (ARFI) reproducibility and the factors influencing it. The intra- and interoperator reproducibility were studied in 33 and 58 patients, respectively. Intraclass correlation coefficient (ICC) was used to assess ARFI reproducibility. The overall intraoperator agreement was better than the interoperator one: ICC 0.90 vs. ICC 0.81. The correlation of repeated ARFI measurements was higher, but not significantly so, in cases in which intraoperator reproducibility was assessed compared with the ones in which interoperator reproducibility was studied: r = 0.848 vs. r = 0.694 (p = 0.08). For both intra- and interoperator reproducibility, the ICCs were smaller in women vs. men (0.88 vs. 0.91 and 0.67 vs. 0.86, respectively), in patients with high body mass index (BMI) ≥25 kg/m² vs. <25 kg/m² (0.88 vs. 0.91 and 0.79 vs. 0.82, respectively), in patients with ascites vs. no ascites (0.80 vs. 0.93 and 0.78 vs. 0.84, respectively) and in noncirrhotic vs. cirrhotic patients (0.77 vs. 0.82 and 0.70 vs. 0.83, respectively).

Intra- and Interoperator Reproducibility of Acoustic Radiation Force Impulse (ARFI) Elastography–Preliminary Results

Chronic viral hepatitis is a common disease in the general population. During chronic hepatitis, the prognosis and clinical management are highly dependent on the extent of liver fibrosis. The fibrosis evaluation can be performed by FibroTest (using serological markers), by Elastography or FibroScan (a noninvasive percutaneous technique using the elastic properties of the hepatic tissue) and by liver biopsy (LB), considered to be the “gold standard”. Currently, there are three techniques for performing LB: percutaneous, transjugular and laparoscopic. The percutaneous LB can be performed blind, ultrasound (US) guided or US assisted. There are two main categories of specialists who perform LB: gastroenterologists (hepatologists) and radiologists, and the specialty of the individual who performs the LB determines if the LB is performed under ultrasound guidance or not. There are two types of biopsy needles used for LB: cutting needles (Tru-Cut, Vim-Silverman) and suction needles (Menghini, Klatzkin, Jamshidi). The rate of major complications after percutaneous LB ranges from 0.09% to 2.3%, but the echo-guided percutaneous liver biopsy is a safe method for the diagnosis of chronic diffuse hepatitis (cost-effective as compared to blind biopsy) and the rate of complications seems to be related to the experience of the physician and the type of the needle used (Menghini type needle seems to be safer). Maybe, in a few years we will use non-invasive markers of fibrosis, but at this time, most authorities in the field consider that the LB is useful and necessary for the evaluation of chronic hepatopathies, despite the fact that it is not a perfect test.

Why, who and how should perform liver biopsy in chronic liver diseases.

Aim: To establish the influence of different factors on the correlation between liver stiffness (LS) measurements by ARFI and liver fibrosis, evaluated by liver biopsy (LB). We assessed the following factors: the success rate (SR) and interquartile range (IQR) interval, the place where ARFI was performed, liver steatosis, the quality of the specimen obtained by LB. Methods: We studied 471 patients: 82 with LB, 82 healthy volunteers and 307 with cirrhosis. We performed 10 valid ARFI measurements, a median value was calculated, expressed in meters/second. Results: Valid measurements were not obtained in 11 patients. There was a direct, strong, correlation (r=0.694) between ARFI and fibrosis (p 30% and/or SR≤60%: r=0.268 (p=0.0001). The quality of the liver specimen (2-3 cm long vs. >3 cm) did not influence the correlation of ARFI with fibrosis. Conclusions: To obtain the best correlation between ARFI and fibrosis, IQR must be <30% and SR≥60%. These technical parameters must be introduced to improve the ARFI value for LS evaluation.

/pdf/factors-that-influence-the-correlation-of-acoustic-radiation-2jmjm6w5wh.pdf

Alina Popescu

Papers

Acoustic Radiation Force Impulse elastography for fibrosis evaluation in patients with chronic hepatitis C: an international multicenter study.

Acoustic radiation force impulse elastography as compared to transient elastography and liver biopsy in patients with chronic hepatopathies.

Intra- and Interoperator Reproducibility of Acoustic Radiation Force Impulse (ARFI) Elastography–Preliminary Results

Why, who and how should perform liver biopsy in chronic liver diseases.

Factors that influence the correlation of acoustic radiation force impulse (ARFI), elastography with liver fibrosis.