Elena Mazzotta

Differences in liver stiffness values obtained with new ultrasound elastography machines and Fibroscan: A comparative study

BACKGROUND AND AIMS Whether Fibroscan thresholds can be immediately adopted for none, some or all other shear wave elastography techniques has not been tested. The aim of the present study was to test the concordance of the findings obtained from 7 of the most recent ultrasound elastography machines with respect to Fibroscan. METHODS Sixteen hepatitis C virus-related patients with fibrosis ≥2 and having reliable results at Fibroscan were investigated in two intercostal spaces using 7 different elastography machines. Coefficients of both precision (an index of data dispersion) and accuracy (an index of bias correction factors expressing different magnitudes of changes in comparison to the reference) were calculated. RESULTS Median stiffness values differed among the different machines as did coefficients of both precision (range 0.54-0.72) and accuracy (range 0.28-0.87). When the average of the measurements of two intercostal spaces was considered, coefficients of precision significantly increased with all machines (range 0.72-0.90) whereas of accuracy improved more scatteredly and by a smaller degree (range 0.40-0.99). CONCLUSIONS The present results showed only moderate concordance of the majority of elastography machines with the Fibroscan results, preventing the possibility of the immediate universal adoption of Fibroscan thresholds for defining liver fibrosis staging for all new machines.

Accuracy of elastography point quantification and steatosis influence on assessing liver fibrosis in patients with chronic hepatitis C.

Elastography point quantification is a novel non‐invasive method for the assessment of liver fibrosis by measuring liver stiffness. The aim of this study was to evaluate the accuracy of elastography point quantification for the diagnosis of liver fibrosis and to assess impact of steatosis on liver stiffness measurement, in a cohort of patients with chronic hepatitis C.

A New Two-Dimensional Shear Wave Elastography for Noninvasive Assessment of Liver Fibrosis in Healthy Subjects and in Patients with Chronic Liver Disease

PURPOSE  To assess the performance of two-dimensional shear wave elastography (2D-SWE) on the GE LOGIQ E9 ultrasound system in a cohort of healthy subjects and to investigate its accuracy in the staging of liver fibrosis in patients with chronic liver disease (CLD) using liver biopsy as a reference standard. MATERIALS AND METHODS  From October 2014 to June 2016, 54 healthy subjects and 174 patients with CLD were consecutively enrolled. Liver fibrosis stage was assessed by the METAVIR scoring system. 18 (10.3 %) and 17 (9.8 %) patients had advanced fibrosis and cirrhosis, respectively. The correlation of liver stiffness measurement (LSM) and continuous variable was assessed using the Spearman rank correlation. The accuracy of 2D-SWE was evaluated with areas under the receiver operating characteristics curves (AUROC). RESULTS  Reliable LSMs were obtained in all subjects. The interobserver agreement ICC was excellent: 0.847. In healthy subjects, gender, but not anthropometric and biochemical data, were correlated with LSM. In patients with CLD, LSM had a strong positive correlation with fibrosis stage (rho = 0.628; p > 0.001). The AUROC was 0.724 for mild fibrosis (F≥ 1), 0.857 for moderate fibrosis (F≥ 2), 0.946 for severe fibrosis (F≥ 3), and 0.935 for cirrhosis (F4). Likewise, good accuracy was observed in the HCV subgroup. The optimal cut-off value in differentiating healthy subjects from CLD patients with any fibrosis was 5.47 kPa with an AUROC of 0.875. CONCLUSION  2D-SWE is a reliable and reproducible method to assess LSM with good diagnostic accuracy to assess liver fibrosis in patients with CLD.

Assessment of Liver Fibrosis with Elastography Point Quantification vs Other Non-Invasive Methods

Background & Aims Elastography point quantification (ElastPQ) is a non‐invasive method for assessing liver fibrosis based on liver stiffness. We evaluated the accuracy of ElastPQ for the staging of liver fibrosis in patients with chronic liver disease (CLD) compared with aspartate transaminase to platelet ratio index, fibrosis‐4 index, and transient elastography (TE), using liver biopsy as reference standard. Methods We performed a retrospective study of 406 patients with CLD of any etiology who underwent liver biopsy analysis from September 2012 through June 2017 at a clinic in Bologna, Italy. We obtained liver stiffness measurements, made by ElastPQ and TE, for 361 patients. Liver fibrosis stage was assessed by the METAVIR scoring system. Areas under the receiver operating characteristic curve (AUROC) were used to assess the diagnostic performance of ElastPQ. Results ElastPQ values correlated with histologic detection of fibrosis (r = 0.718; P < .001). The AUROC values were 0.856 for detection of significant fibrosis (F≥2), 0.951 for advanced fibrosis (F≥3), and 0.965 for cirrhosis. The best cut‐off values identified for classifying patients with F≥2, F≥3, or cirrhosis were 6.0 kPa, 6.2 kPa, and 9.5 kPa, respectively: these were lower than those for TE. Comparison of ElastPQ with TE data resulted in superimposable diagnostic accuracy of both methods for each stage of liver fibrosis. Both elastography techniques performed better than aspartate transaminase to platelet ratio index or fibrosis‐4 index scores (P < .05 for all AUROC comparisons). Conclusions ElastPQ has good to excellent performance for the non‐invasive staging of liver fibrosis in patients with CLD. ElastPQ identified patients with fibrosis or cirrhosis with levels of accuracy that were not inferior to those of TE, and outperformed serum fibrosis indexes in identifying each stage of liver fibrosis.