Acoustic Impedance Analysis with High-Frequency Ultrasound for Identification of Fatty Acid Species in the Liver

Ultrasound Med Biol. 2017 Mar;43(3):700-711. doi: 10.1016/j.ultrasmedbio.2016.11.011. Epub 2016 Dec 28.

Abstract

Acoustic properties of free fatty acids present in the liver were studied as a possible basis for non-invasive ultrasonic diagnosis of non-alcoholic steatohepatitis. Acoustic impedance was measured for the following types of tissue samples: Four pathologic types of mouse liver, five kinds of FFAs in solvent and five kinds of FFAs in cultured Huh-7 cells. A transducer with an 80-MHz center frequency was incorporated into a scanning acoustic microscopy system. Acoustic impedance was calculated from the amplitude of the signal reflected from the specimen surface. The Kruskal-Wallis test revealed statistically significant differences (p < 0.01) in acoustic impedance not only among pathologic types, but also among the FFAs in solvent and in cultured Huh-7 cells. These results suggest that each of the FFAs, especially palmitate, oleate and palmitoleate acid, can be distinguished from each other, regardless of whether they were in solution or absorbed by cells.

Keywords: Acoustic impedance; Free fatty acid; Lipid droplet; Liver; Non-alcoholic steatohepatitis; Scanning acoustic microscopy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Disease Models, Animal
  • Electric Impedance*
  • Fatty Acids / metabolism*
  • Liver / diagnostic imaging
  • Liver / metabolism*
  • Mice
  • Non-alcoholic Fatty Liver Disease / diagnosis
  • Non-alcoholic Fatty Liver Disease / diagnostic imaging
  • Non-alcoholic Fatty Liver Disease / metabolism*
  • Ultrasonography / methods*

Substances

  • Fatty Acids