Introduction
Multiparametric Ultrasound (MP-US) is emerging as a key tool for liver disease assessment and management, offering rapid, non-invasive insights into tissue characteristics, usually accessible only through liver histology1,2. Steatosis and inflammation, main factors in fibrosis and cirrhosis progression, should be ideally detected and quantified early, aiding in the diagnosis and risk assessment of chronic liver disease (CLD)3. MP-US combines ultrasound wave propagation techniques: Shear Wave Dispersion (SWD) evaluates frequency-dependent changes in wave velocity reflecting inflammation-related viscosity; Shear Wave Elastography (SWE) estimates liver stiffness as indirect marker of fibrosis; Attenuation Ultrasound (USAT) and speed of sound (TSSI) assess hepatic fat content measuring energy loss and sound speed3,4.
Aims & Methods
The study aimed to assess the accuracy of USAT/TSSI, SWE and SWD measured by a novel MP-US device (Resona A20, Mindray) compared to liver histology to evaluate steatosis, fibrosis and inflammation.
This single-centre observational, prospective study conducted from May to November 2024 included adult patients (≥18 years) with suspected CLD, referred for MP-US evaluation and percutaneous liver biopsy.
Parameters were obtained in a single session by placing a 2–3 cm diameter Region of Interest (ROI) at least 1.5 cm below the liver capsule.
Five valid measurements - defined by a Motion Stability Index (M-STB) of 5 and a high reproducibility (green zone on colorimetric map) - were acquired for each technique, collecting mean, median, interquartile range (IQR), IQR/median, standard deviation (SD) and SD/mean4,5.
Histology was the reference standard for grading inflammation, fibrosis and steatosis using defined scoring systems.
Results
A total of 78 patients (46 women; mean age 51.6 years) were included in the study: 42 with MASLD, 20 with PSVD or nonspecific cholangiopathies, 9 with AIH and 7 with PBC.
USAT values increased progressively with steatosis severity, showing statistically significant differences across all stages (S0 vs S1, S1 vs S2 and S0 vs S1–3; p < 0.001). ROC curve analysis demonstrated high diagnostic accuracy with an AUC of 0.801 for S0 vs S1, 0.977 for S1 vs S2 and peak performance for S0–1 vs S2–3 (AUC 0.992, sensitivity 100%, specificity 95.1%). Optimal USAT cut-off values to classify mild, moderate and severe steatosis were 0.55, 0.67, and 0.75, respectively.
Conversely, TSSI values decreased with increasing steatosis grade. ROC analysis revealed moderate diagnostic performance of TSSI in distinguishing S0 from S1 (AUC 0.77) and S0–1 from S2–3 (AUC 0.76). A moderate inverse correlation was observed between TSSI and USAT values (ρ = –0.53, p < 0.001).
SWE values increased with fibrosis stage according to the METAVIR scoring system, demonstrating good performance in detecting advanced fibrosis (p = 0.024). However, most patients exhibited either no fibrosis (F0) or mild fibrosis (F1) on liver histology, limiting SWE overall diagnostic performance.
Viscosity values showed a non-significant upward trend with increasing inflammation. Standard liver function tests demonstrated only a weak correlation with histological inflammation. Notably, SWD approached statistical significance in differentiating the presence of at least mild inflammation from no inflammation (A0 vs A123).
Conclusion
MP-US offers valuable non-invasive insights into liver tissue characteristics reflecting histological findings. Further studies are warranted to support the non-invasive assessment of key pathological features, potentially replacing liver biopsy.
References
1. Grgurevic, I., Tjesic Drinkovic, I. & Pinzani, M. Multiparametric ultrasound in liver diseases: an overview for the practising clinician. Postgrad Med J 95, 425–432 (2019).
2. Sumida, Y., Nakajima, A. & Itoh, Y. Limitations of liver biopsy and non-invasive diagnostic tests for the diagnosis of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. World J Gastroenterol 20, 475–485 (2014).
3. Garcovich, M. et al. Shear Wave Dispersion in Chronic Liver Disease: From Physical Principles to Clinical Usefulness. Journal of Personalized Medicine 2023, Vol. 13, Page 945 13, 945 (2023).
4. Ferraioli, G. et al. WFUMB Guidelines/Guidance on Liver Multiparametric Ultrasound. Part 2: Guidance on Liver Fat Quantification. Ultrasound Med Biol 50, 1088–1098 (2024).
5. Ferraioli, G. et al. WFUMB Guideline/Guidance on Liver Multiparametric Ultrasound: Part 1. Update to 2018 Guidelines on Liver Ultrasound Elastography. Ultrasound Med Biol 50, 1071–1087 (2024).
