Purpose: We aimed to compare vibration-controlled transient elastography (VCTE) with shear wave elastography (SWE) without previous analysis and generate regression equations between VCTE and new point SWE using combination-elastography.
Methods: Overall, 829 patients with chronic liver disease were enrolled in this study. Patients with a skin-liver capsule distance > 25 mm were excluded. The reproducibility of VCTE and SWE was confirmed in a phantom study and a clinical study. Considering that combination-elastography allows measurement based on strain elastography, a similar analysis was performed for the liver fibrosis index (LFI), which is a quantitative value for evaluation of liver fibrosis calculated using strain elastography image features. Regression equations between the VCTE and SWE values were obtained based on linear regression analysis.
Results: In the phantom study and clinical study, there was a strong correlation between VCTE and SWE [r = 0.995 (p < 0.001) and r = 0.747 (p < 0.001), respectively). The regression equation between VCTE and SWE was VCTE (kPa) = 1.09 × point SWE (kPa) - 0.17. The Bland-Altman plots revealed no statistically significant bias. Meanwhile, there was no correlation between VCTE and LFI (r = 0.279). There was a statistically significant bias between VCTE and LFI in the Bland-Altman plots. The inter-operator reliability showed a good intraclass correlation coefficient of 0.760 (95% confidence interval: 0.720-0.779).
Conclusion: Liver stiffness measured using point SWE was comparable to that measured using VCTE.
Keywords: Liver stiffness; Shear wave elastography; Strain elastography; Vibration-controlled elastography.
© 2023. The Author(s), under exclusive licence to The Japan Society of Ultrasonics in Medicine.