A preliminary study of liver fat quantification using reported longitudinal ultrasound speed of sound and attenuation parameters

TL;DR

This study proposes a new ultrasound-based framework to noninvasively quantify liver fat by estimating fat volume from speed of sound and attenuation measurements, showing promising agreement with existing methods.

Contribution

It introduces a novel estimation method using ultrasound speed and attenuation data to assess liver steatosis, based on a classical composite elastic material model.

Findings

Estimation method agrees with independent fat measurements.

Framework applicable to clinical ultrasound scanners.

Potential for improved noninvasive liver fat assessment.

Abstract

The quantification of liver fat as a diagnostic assessment of steatosis remains an important priority for noninvasive imaging systems. We derive a framework in which the unknown fat volume percentage can be estimated from a pair of ultrasound measurements. The precise estimation of ultrasound speed of sound and attenuation within the liver are shown to be sufficient for estimating fat volume assuming a classical model of the properties of a composite elastic material. In this model, steatosis is represented as a random dispersion of spherical fat vacuoles with acoustic properties similar to those of edible oils. Using values of speed of sound and attenuation from the literature where normal and steatotic livers were studied near 3.5 MHz, we demonstrate agreement of the new estimation method with independent measures of fat. This framework holds the potential for translation to clinical scanners where the two ultrasound measurements can be made and utilized for improved quantitative assessment of steatosis.