Echo envelope analysis method for quantifying heterogeneity of scatterer distribution for tissue characterization of liver fibrosis

The probability density function (PDF) of the echo signal envelope is an important factor for ultrasound tissue characterization (TC). Fibrotic tissue is inhomogeneous; therefore, its envelope PDF cannot be accurately modeled by a single PDF. Additionally, some regions have variable scatterer densities. In order to detect and characterize the fibrotic liver quantitatively, we examined the relationship between the scatterer distribution and the PDF of echo envelopes of inhomogeneous scattering media using computer simulations. Then, the analysis parameters in the simulated fiber tissue were successfully used to characterize fibrosis in clinical data sets.