Quantification of Steatosis and Fibrosis using a new system implemented in an ultrasound machine.

Abstract

The study compared the usefulness of 2D-SWE and attenuation measurements obtained using Aplio i800 from Canon together with Transient Elastography (TE) and the Controlled Attenuation Parameter (CAP) as the reference method. We included 112 consecutive adults with reliable LS measurements, 44 healthy subjects and 68 subjects with chronic hepatopathies in whom liver stiffness (LS) and steatosis were evaluated in the same session employing two elastography techniques: Transient Elastography (TE) with Controlled Attenuation Parameter (CAP) implemented on the FibroScan® 530 Compact system and Two Dimensional Shear Wave Elastography (2D-SWE) with Attenuation Imaging (ATI) installed on the Aplio i800 series ultrasound system. Reliable measurements were defined as the median value of 10, respectively 5 valid LS measurements for TE and 2D-SWE, with an interquartile range interval/median ratio (IQR/M) <30%. A very strong positive correlation was found between LS values obtained by TE and 2D-SWE: r=0.88, p<0.0001 and between the attenuation coefficients of steatosis obtained by CAP and ATI, r=0.81, p<0.0001. The best cut-off values by 2DSWE for predicting different stages of liver fibrosis were: for F≥2 - 7.9 kPa and F=4 - 11.7 kPa. Regarding steatosis, the best ATI cut-off values were: for S≥1 - 0.79 dB/cm/mHz and for S3 - 0.86 dB/cm/mHz. 2D-SWE and ATI measurements with the new system strongly correlated with TE and CAP results.