Comparison of three ultrasound based elastographic techniques in children and adolescents with chronic diffuse liver diseases.

UNLABELLED Non-invasive techniques for liver fibrosis assessment were developed for adults and recent researches tested their accuracy in children. The only validated elastographic method for non-invasive liver fibrosis evaluation in children is Transient Elastography (TE). The aim of our study was to investigate the feasibility of liver stiffness (LS) measurement in paediatric patients with chronic liver diseases by means of Acoustic Radiation Force Impulse Elastography (ARFI) and 2D-Shear Wave Elastography (2D-SWE), compared to TE as reference method. MATERIAL AND METHODS We enrolled 54 consecutive children and adolescents with different chronic liver diseases. All patients were examined by means of TE, ARFI, and 2D-SWE. All measurements were performed in the right liver lobe, in the same session, in fasting condition. We considered reliable LS elastographic measurements as follows: for TE and ARFI - the median value of ten measurements with a success rate >/=60% and an interquartile range<30%, for 2D-SWE - the median value of five measurements. RESULTS The successful measurement rate for TE was 94.4% (51/54). Taking TE as a reference method, sensitivity of ARFI for detecting fibrosis F1 was 71.42%, for F2-77.77%, for F3-62.5% and for F4-71.42%. Sensitivity of 2D-SWE for detecting F1 was 92.85%, for F2-83.33%, for F3-87.5% and for F4-85.71%. We found significant correlations between TE and 2D-SWE on the entire lot (Kappa correlation factor=0.843, p=0.001). Analyzing the subgroup with SR=60%-70%, we did not find significant correlation between TE and ARFI (Kappa correlation factor=0.172, p=0.452). Assessing the subgroup with SR>70%, we found a significant correlation between TE and ARFI (Kappa correlation factor=0.761, p=0.001). CONCLUSIONS Overall, 2D-SWE correlate better with TE compared to ARFI in children. Excluding patients with less satisfactory technical parameters, we obtained significant correlations between all three methods. Both SWE and ARFI are non-invasive techniques feasible of performing on paediatric patients along with TE.