The accumulation of fat droplets within the liver is an important marker of liver disease. This study assesses gradations of steatosis in mouse livers using crawling waves, which are interfering patterns of shear waves introduced into the liver by external sources. The crawling waves are detected by Doppler ultrasound imaging techniques, and these are analyzed to estimate the shear wave speed as a function of frequency between 200 and 360 Hz. In a study of 70 mice with progressive increases in steatosis from 0% to >60%, increases in steatosis are found to increase the dispersion, or frequency dependence, of shear wave speed. This finding confirms an earlier, smaller study and points to the potential of a scoring system for steatosis based on shear wave dispersion.
Keywords: Crawling waves; Dispersion; Fatty liver disease; Medical ultrasound imaging; Shear wave elasticity imaging; Steatosis; Viscoelastic tissue models.
Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.