Between‐Visit Reproducibility of Shear Wave Viscoelastography in Volunteers and Patients With Metabolic Dysfunction‐Associated Steatotic Liver Disease

Objective To assess the reproducibility of six ultrasound (US)‐determined shear wave (SW) viscoelastography parameters for assessment of mechanical properties of the liver in volunteers and patients with biopsy‐proven metabolic dysfunction‐associated steatotic liver disease (MASLD) or metabolic dysfunction‐associated steatohepatitis (MASH). Methods This prospective, cross‐sectional, institutional review board‐approved study included 10 volunteers and 20 patients with MASLD or MASH who underwent liver US elastography twice, at least 2 weeks apart. SW speed (SWS), Young's modulus ( E ), shear modulus ( G ), SW attenuation (SWA), SW dispersion (SWD), and viscosity were computed from radiofrequency data recorded on a research US scanner. Linear mixed models were used to consider the sonographer on duty as a confounder. The reproducibility of measurements was assessed by intraclass correlation coefficient (ICC), coefficient of variation (CV), reproducibility coefficient (RDC), and Bland‐Altman analyses. Results The sonographer performing the exam had no impact on viscoelastic parameters ( P > .05). ICCs of SWS, E , G , SWA, SWD, and viscosity were, respectively, 0.89 (95% confidence intervals [CI]: 0.79‐0.95), 0.81 (95% CI: 0.79‐0.95), 0.90 (95% CI: 0.80‐0.95), 0.96 (95% CI: 0.93‐0.98), 0.78 (95% CI: 0.60‐0.89), and 0.90 (95% CI: 0.80‐0.95); CVs were 11.9, 23.3, 24.2, 10.1, 29.0, and 32.2%; RDCs were 33.0, 64.5, 66.9, 27.7, 80.3, and 89.2%, and Bland‐Altman mean biases and 95% limits of agreement were −0.05 (−0.45, 0.35) m/s, −0.61 (−5.33, 4.10) kPa, −0.25 (−2.06, 1.56) kPa, −0.01 (−0.27, 0.26) Np/m/Hz, −0.09 (−7.09, 6.91) m/s/kHz, and −0.33 (−2.60, 1.94) Pa/s, between the two visits. Conclusion US‐determined viscoelastography parameters can be measured with high reproducibility and consistency between two visits 2 weeks apart on the same ultrasound machine.