| Abstract: | Ultrasound-based shear wave elastography (SWE) has recently gained substantial attention for non-invasive assessment of liver fibrosis. The purpose of this study was to perform an intra-individual comparison between 2-D shear wave elastography (2-D-SWE with a GE system) and Virtual Touch Tissue Quantification (VTTQ with a Siemens system) to assess whether these can be used interchangeably to grade fibrosis. Ninety-three patients (51 men, 42 women; mean age, 54 y) with liver disease of various etiologies (hepatitis B virus?=?47, hepatitis C virus?=?22; alcohol?=?6, non-alcoholic steatohepatitis?=?5, other?=?13) were included. Using published system-specific shear wave speed cutoff values, liver fibrosis was classified into clinically non-significant (F0/F1) and significant (≥F2) fibrosis. Results indicated that intra-modality repeatability was excellent for both techniques (GE 2-D-SWE: intra-class correlation coefficient?=?0.89 [0.84–0.93]; VTTQ: intra-class correlation coefficient?=?0.90 [0.86–0.93]). Intra-modality classification agreement for fibrosis grading was good to excellent (GE 2-D-SWE: κ?=?0.65, VTTQ: κ?=?0.82). However, inter-modality agreement for fibrosis grading was only fair (κ?=?0.31) using published system-specific shear wave speed cutoff values of fibrosis. In conclusion, although both GE 2-D-SWE and Siemens VTTQ exhibit good to excellent intra-modality repeatability, inter-modality agreement is only fair, suggesting that these should not be used interchangeably. |
