Quantitative Ultrasound-Based Compression and Shear Wave Attenuation for Metabolic Dysfunction-Associated Steatotic Liver Disease Grading.

OBJECTIVE: Ultrasound compression-wave attenuation (CWA) and shear-wave attenuation (SWA) quantify distinct mechanisms of ultrasonic energy loss in tissues and may provide complementary information for liver disease characterization. This study compares their diagnostic performance across the spectrum of metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (MASH). METHODS: In this prospective, cross-sectional study, 55 adults (13 healthy volunteers, 42 biopsy-proven MASLD patients) underwent ultrasound between 2020 and 2023. CWA and SWA were computed head-to-head on same acquisitions of participants. Correlations between CWA and SWA with histopathology and MRI-proton density fat fraction (PDFF) were assessed. Multivariate and area under the curve (AUC) analyses were performed. RESULTS: Both CWA and SWA correlated strongly with MRI-PDFF (r = 0.71 and 0.77, p < 0.001). Correlations with histopathology were 0.66 (steatosis), 0.61 (inflammation), 0.49 (ballooning), and 0.46 (fibrosis) for CWA; and 0.74, 0.53, 0.40, and 0.19 for SWA. Multivariable regressions confirmed independent associations with steatosis (CWA R² = 0.54, p < 0.001; SWA R² = 0.57, p < 0.001). For steatosis grading, AUCs for CWA versus SWA were 0.96 vs. 0.91 (S0 vs. ≥S1), 0.85 versus 0.87 (≤S1 vs. ≥S2), and 0.75 versus 0.88 (≤S2 vs. S3; p < 0.05) and for MASH detection the highest AUCs for CWA versus SWA were 0.94 versus 0.88. CONCLUSION: CWA and SWA capture complementary mechanisms of energy loss, CWA reflecting lipid-related scattering and absorption, SWA reflecting viscoelastic dissipation. Both correlate strongly with MRI-PDFF and histopathology, though they show distinct secondary associations. Their combined assessment within a single ultrasound examination improves noninvasive steatosis grading and may reduce reliance on biopsy or MRI.