3D multiparametric ultrasound imaging of steatotic liver disease in a study with male rats.

Steatotic liver disease (SLD) is the most prevalent chronic liver disease worldwide, requiring precise diagnosis and ongoing monitoring. Ultrasound imaging (USI) is widely used to diagnose steatosis, but it suffers from limited sensitivity/specificity and/or high observer variability. Assessment of hepatic vascular changes during SLD progression has diagnostic relevance because steatosis can induce sinusoidal microvascular dysfunction. Here, we demonstrate 3D multiparametric hepatic USI of SLD in living male rats by coordinating ultrafast Doppler imaging (UFD) and quantitative USI. Vessel volume, perfusion, branching, and tortuosity are quantified from 3D UFD, while tissue attenuation level and heterogeneity are estimated through quantitative USI. Over 8 weeks, hepatic vascular alterations were quantitatively monitored in vivo via 3D UFD during the progression and recovery periods of the SLD. Changes in vascular indices were strongly correlated with hepatic fat accumulation revealed by histopathology, demonstrating great diagnostic potential. Finally, all-around US score comprising five US indices showed a Pearson's coefficient of 0.96 and an average balanced accuracy of 92%, exceeding the performance of each US index alone. Although the translatability to human liver imaging remains limited, these findings suggest that 3D multiparametric USI could serve as a valuable modality for the diagnosis and monitoring of SLD.