Influences of structural factors of biological media on the acoustic nonlinearity parameter B/A.

The influence of structural factors of biological media on the acoustic nonlinearity parameter B/A have been studied at the tissue, cellular, and molecular levels, using the thermodynamic and finite amplitude methods. B/A was determined as the structural factors of the media were altered physically and biochemically, while chemical composition was maintained unchanged. Significant structural dependencies of B/A were observed at all three levels; 26% of the dry weight contribution to the total B/A (the B/A value with water contribution subtracted) is due to the cell-cell adhesive force in liver tissue, 20% is due to the hepatocyte cellular structure, and 15% is due to secondary and tertiary protein structure.